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VLIZ
VLIZ SPECIAL PUBLICATION 6 7
6/02/14 23:02
VLIZ
BOOK OF ABSTRACTS
VLIZ YOUNG MARINE SCIENTISTS’ DAY
VIVES, Brugge
7 March 2014
VLIZ SPECIAL PUBLICATION 67
This publication should be quoted as follows:
Jan Mees and Jan Seys (Eds). 2014. Book o f abstracts - VLIZ Young S cientists’ Day. Brugge, Belgium,
7 March 2014. VLIZ Special Publication 67. Vlaams In stitu u t voor de Zee - Flanders Marine Institute
(VLIZ): Oostende, Belgium. 1 78 + x ii p.
Vlaams In stitu u t voor de Zee
Flanders Marine Institute
VLIZ - InnovOcean site
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8400 Oostende, Belgium
Tel. +32-(0)59-34 21 30
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Photo cover:
Scenery o f the beach nature reserve ‘Bay o f He is t’ durin g the Santa Claus storm o f 5 December 201 3
(Misjel Decleer)
Reproduction is authorized, provided th a t appropriate m ention is made o f the source.
ISSN 1377-0950
PREFACE
This is the ‘Book o f A b stra cts’ o f the 14th e dition o f the VLIZ Young Marine S cientists’ Day, a one
day event th a t was organised on 7 March, 2014 in VIVES, Brugge.
This annual event has become more and more successful over the years. With more than 300
participants and over 100 scientific co ntrib u tio n s, it is fa ir to say th a t it is the place to be fo r
Flemish marine researchers and fo r the end-users o f th e ir research. It is an im p o rta n t netw orking
o p p o rtu n ity, where young scientists can meet and interact w ith th e ir peers, learn from each other,
build th e ir personal professional netw ork and establish links fo r collaborative and interdisciplina ry
research.
Marine scientists fro m all Flemish universities and scientific institutes - and representing all marine
science disciplines - have co ntribu te d to th is volume. The book thus illustrates the diversity, q ua lity
and relevance o f the marine sciences in Flanders (and Belgium): it provides a beautiful and
comprehensive snapshot o f the state-of-the-art o f marine scientific research in Flanders in 2014.
Young scientists present th e ir research in an e xciting way and com m unicate th e ir fascinating
science - and its im portance to society - to the w ider public. We thus hope to dem onstrate the
excellence o f Flemish marine science and to increase its national and international visibility.
The volume o f research th a t is presented here holds a great promise fo r the fu tu re . It shows th a t
marine science is a very lively discipline in Flanders, and th a t a new generation stands ready to
address the grand challenges and o p p o rtu n itie s th a t our seas and oceans represent.
I w ant to congratulate all participants w ith th e ir co ntrib u tio n s, and I invite them all to actively
participate in VLIZ-events and activities in the future.
Brugge, 7 March 2014
Prof. Dr Jan Mees
General D irector VLIZ
TABLE OF CONTENTS
PREFACE...............................................................................................................................iii
LAUREATES ANNUAL VLIZ THESIS AWARDS MARINE SCIENCES 2013
De
Waegemaeker Jeroen. Klim aatverandering ais m oto r vo or een vernieuwd
kusttoerism e? Potenties van een gecom partim enteerde ku ststroo k voor het
ku stto erism e ......................................................................................................................................... 2
Schmidt-Petersen Julia. What influences predation by C oralliophila? Exploring the
relationships between corals, sym biotic zooxanthellae, and corallivorous
g a strop o ds.............................................................................................................................................7
LAUREATE ANNUAL VLIZ NORTH SEA AWARD 2013
de Brauwere Anouk. M ulti-disciplinary/scale m odeling o f the Scheldt Estuary and tidal
river netw ork (a collection o f articles from 2009 to to d a y )....................................................10
ORAL, POSTER & DEMO PRESENTATIONS
M atthias, Frederic Francken, Michael Fettweis, Dries Van den Eynde and Lieven
Naudts. The firs t buoy fo r continuous m easuring o f surface Suspended
Particulate M atter concentration on the Belgian inner s h e lf...................................................16
Barbut Léo, Geneviève Lacroix and Filip A.M. Volckaert. How sensitive is sole larval
dispersal in the North Sea to the param etrization o f larval duration? A
m odelling stu dy................................................................................................................................. 1 7
Bekaert Karen, Daphné Deloof, Lisa Devriese, Sara Maes, Kevin Vanhalst, D irk
Verhaeghe and Johan Robbens. Influence o f the storage m ethod on the
q u a lity o f Norway lobster (Nephrops n o rve g icu s).................................................................... 1 8
Beuckels Annelies, Erik Sm olders and Koenraad Muylaert. Wastewater trea tm en t using
m icro alga e .......................................................................................................................................... 1 9
Blomm aert Lander, Alexandre Barnett, Vona Meleder, Pierre Gaudin, Wim Vyverman,
C hristine Dupuy, Johann Lavaud and Koen Sabbe. Ecological niche predicts
p ho top rote ction capacity o f m icro ph ytob en th ic diatom s inhabiting intertida l
m u d fla ts ...............................................................................................................................................20
Bourgois Jan. A lifetim e inspired by the ocean: marine environm ental effects on
human p hysiolo gy.............................................................................................................................21
Breine Naomi T., Sofie Vandendriessche and Kris Hostens. Prevalence o f the parasites
Sacculina c a rc in i on Liocarcinus holsatus and Peltogaster p a g u ri on Pagurus
bernhardus in the Belgian part o f the North Sea...................................................................... 22
- V-
Brihaye Esther,T hib au t Bouveroux, Steven Degraer, Valérie Dulière, Jan Haelters,
Sylvain Pezeril and T hierryJauniaux. Where did com m on porpoise (Phocoena
phocoena) come fro m before stra n d in g ? ......................................................................................23
C attrijsse Andre, Thanos G kritzalis, Karen Rappé, Michiei T ’J ampens and Wim
Versteeg. The RV Simon Stevin: home o f the newest oceanographic to ols fo r
scien tists...............................................................................................................................................24
Cohen-Rengifo Mishal, Patrick Flammang and Philippe Dubois. Tube fo o t mechanical
properties in the sea urchin Paracentrotus livid us from habitats presenting a
range o f seawater v e lo c itie s ............................................................................................................ 25
Collard France, Krishna Das and Eric Parmentier. M icroplastics caught in herring gili
rakers: illu stra tio n by scanning electron m ic ro s c o p y ............................................................... 26
C ollart Tim, Kerry Flowell, Fleather Stewart, Jean-François Bourillet, Estefanía Llave,
D om inique Blamart and David Van Rooij. Using cold-w ater coral m in i­
m ounds as analogue fo r g ia nt mound grow th: assessment o f environm ental
drivers and anthropogenic im p a c t.................................................................................................27
Colson Liesbet, Gert Van Hoey, Jan Vanaverbeke and Magda Vincx. Ecological study o f
foreshore nourishm ent at the Flemish c o a s t...............................................................................28
Cransveld Alice, David A m o urou x, Emmanuil Koutrakis, Sylvain Bé rail, Caiyan Feng,
Julien Barre, Joseph Schnitzler and Krishna Das. Using stable isotopes o f
m ercury and m ethylm ercury to discrim inate contam ination profiles between
sea bass, D icentrarchus labrax, p o p u la tio n s ..............................................................................29
Dan Sebastian, Corrado Ahornare, Daphné Thoon, T om o hiro Suzuki, Tim Spiesschaert
and Toon Verwaest. O vertopping induced by oblique waves at Station quay O o ste n d e ..............................................................................................................................................30
Dasan A n to n y Franklin, Rindra Rasoloniriana, A m it Kumar Sinha, Ronny Blust and
Gudrun De Boeck. Adaptive responses to high environm ental am m onia in
European sea bass acclim ated to d iffe re n t s a lin itie s ................................................................ 31
De Backer Annelies, Jannes Heusinkveld, Harriëtte Holzhauer, Jan Van Dalfsen and Kris
Hostens. The effects o f a large-scale shoreface nourishm ent on the shallow
coast epibenthos and fish c o m m u n itie s .......................................................................................32
De Cauwer Karien, Yvan Stojanov, Jordi Sorribas, Paolo Diviacco, Marie-Paule Corre
and Alessandro Busato. Standardization at sea: ongoing developm ents fo r
EARS event lo g g in g ............................................................................................................................33
De Clercq Maikel, Tine Missiaen and Z urita Hurtado Oscar. Buried beneath the sea:
m apping the archeological potential o f the Belgian C ontinental s h e lf.................................35
De Moor W illem and Ángel E. Muñiz Pi n ie Ila. JPI Oceans - Joint Program m ing Initiative
fo r Healthy and Productive Seas and Oceans...............................................................................36
De Raedemaecker Fien. Marine Biotechnology ERA-NET: a European fu n d in g initiative
fo r inte rd iscip lin a ry research and c o lla b o ra tio n ......................................................................... 37
De Raedemaecker Fien and Nancy Nevejan. New Flemish Aquaculture Platform w ill
develop a long term vision fo r aquaculture in Flanders............................................................38
De Rijcke Maarten, Michiei B. Vandegehuchte, Nancy Nevejan, Julie Vanden Bussche,
Lynn Vanhaecke and Colin R. Janssen. Spatfall in a changing environm ent:
m ind the H AB......................................................................................................................................39
Bart De Smet, An-Sofie D’Hondt, Pieterjan Verhelst, Jérôme Fournier, Laurent Godet,
Nicolas Desroy, M arijn Rabaut, Magda Vincx and Jan Vanaverbeke. New
insights in the structuring role o f Lanice conchilega reefs in inte rtid a l food
webs: a focus on epi- and h yp e rb e n th o s..................................................................................... 40
- vi -
De Swaef Evelien, Marlien Schaeck, Wim Van Den Broeck, Peter Bossier, K risto f
Dierckens and Annem ie Decostere. G notobiotic models fo r seabass
(D icentrarchus labrax) and Dover sole (Solea solea): the chain is o nly as
strong as its weakest lin k .................................................................................................................41
Debusschere Elisabeth, Bert De Coensel, D om inique Adriaens, Aline Bajek, Dick
Botteldooren, Kris Hostens, Jan Vanaverbeke, Sofie Vandendriessche, Karl
Van Ginderdeuren, Magda Vincx and Steven Degraer. Im pact o f pile-driving
o f offshore m onopile fo un da tio ns on young sea bass..............................................................42
Dekeyzer Stefanie, Klaas Deneudt, Leen Vandepitte, Annelies G offin, Simon Claus and
Francisco Hernandez. The Flemish co n trib u tio n s to LifeWatch - A general
overview ................................................................................................................................................43
Delerue-Ricard Sophie, Naria Coscia, Léo Barbut, Geneviève Lacroix, Andreas Vanden
Bavière, Johan Robbens and Filip A.M. Volckaert. Assessing connectivity in
young fla tfish and its im plem entation in fisheries m anagem ent...........................................44
Delgado Claudia, A ditya Kakodkar and Peter Pissierssens. OceanTeacher Global
Academy: OceanTeacher goes g lo b a l........................................................................................... 45
Demierbe Thibaud, Rosa Maria van der Ven, Puspitaningasih Sutrisno and Mare
Kochzius. C onnectivity o f the coral A cro po ra tenuis in the Spermonde
A rc h ip e la g o ......................................................................................................................................... 47
Depestele Jochen, Koen Degrendele, Hans Polet, Mare Roche, loma Teal, Bart
Vanelslander and Adriaan Rijnsdorp. One plus one is three: traw ling
differences from m ulti-beam im agery........................................................................................... 48
Deprez Tim , Pieter Blondeel, W endy Massart and Magda Vincx. MARES jo in t doctoral
program m e on marine ecosystems health and co n s e rv a tio n ................................................. 49
Deprez
Tim , Pieter Blondeel, Wendy Massart and Magda Vincx. First MARES
Conference Marine Ecosystems Health and C on serva tion ...................................................... 50
Deprez Tim, Danae Kapasakali, Tim tk in t and Magda Vincx. Towards a user-friendly
guide fo r marine education and tra in in g ......................................................................................51
D eruytter David, M ichiei Vandegehuchte, Karel De Schamphelaere, Ronny Blust and
Colin R. Janssen. Copper to x ic ity in mussels: do salinity, organic m atter and
p opulation h istory m a tte r? .............................................................................................................. 52
Desender Marieke, Koen Chiers, Bart Verschueren, Hans Polet, Luc Duchateau,
Puvanendran Velm urugu, A tle Mortensen and Annem ie Decostere. Electrical
traw ling fo r brown shrim p: Im pact on young life stages in nurseries and
spawning areas?................................................................................................................................. 53
Devolder Mia, Karien De Cauwer, Ruth Lagring, Serge Scory and Yvan Stojanov.
Belgian marine m on itoring data at the BM DC.............................................................................54
Dulière Valérie, Nathalie Gypens, Christiane Lancelot, Patrick Luyten, Xavier Desmit
and Geneviève Lacroix. Linking human activities to e utrophication along the
river-ocean continuum w ith an ecological m o d e l....................................................................... 55
Fettweis Michael, M atthias Baeye, D im itry Van der Zande, Dries Van den Eynde and
B yu ng joo n Lee. Seasonality o f nearshore marine snow in the southern North
Sea.......................................................................................................................................................... 56
Filim onova Valentina, Marleen De Troch, Fernando Gonçalves and Ana M.M.
Gonçalves. The effects o f anthropogenic stressors on the food q u a lity in
estuarine sy s te m s .............................................................................................................................. 57
Fourdrilis Séverine, Vanya Prévôt, Marine M onjardez and T hie rry Backeljau. Genetic
structure and connectivity assessment w ith hyper-polym orphic data in a
high-dispersal potential m ollusk in North A tla n tic .....................................................................59
- vii -
Frank Céline, James Kairo, Mohamed O.S. Mohamed, Nico Koedam and Farid
Dahdouh-Guebas. Regeneration o f a m angrove fo re st in a nature reserve
and p articip a tory m anagem ent co nte xt (Mida Creek, Kenya)................................................. 60
Géoris
Sylvestre, Djedje Kungula Makoso and Farid Dahdouh-Guebas. Are the
mangroves o f Sokone (Sine Saloum, Senegal) u tilized in a sustainable way?
An analysis m erging socio-ecologic interviews w ith vegetation science.............................. 61
Germ onpré Matthias, hiana Ortega Yam om oto, Agustín Sánchez-Arcilla and Jaak
M onbaliu. Wave m odeling Catalan coast: an in te rc o m p a ris o n ............................................... 62
Ghyoot Caroline, Christiane Lancelot and Nathalie Gypens. M odelling m ix o tro p h y in
eutrophied coastal ecosystem s...................................................................................................... 63
Grosemans Tara, Sofie Derycke and Tom Moens. Investigating evolution o f closely
related, sym patric cryptic species using com plete m itoch on drial D N A............................... 64
H ae ltersjan , Valérie Dulière, Laurence Vigin and Steven Degraer. Towards a model fo r
the re d istrib u tio n o f harbour porpoises (Phocoena phocoena) due to pile
driving in Belgian w aters...................................................................................................................65
Hamza
Am ina Juma, James Kairo, Nico Koedam and Farid Dahdouh-Guebas.
Mangroves and livelihood - An assessment o f livelihood projects in the
m angrove ecosystems along the Kenyan c o a s t.......................................................................... 66
Hillen Jasmien, Maria Coscia and Filip Volckaert. Developm ent o f e ffic ie n t genetic
m arkers to trace fish fraud and IUU fis h in g .................................................................................67
Huyghe Filip and Mare Kochzius. Analysis o f connectivity in the Skunk Clown Fish
using a com bination o f m icrosatellite and m itochondrial genetic m arkers.........................68
Incoul Annelies, Philippe De Maeyer, Bart De Wit, Alain De Wulf, Tine Missiaen,
T im o th y Nuttens, C ornelis Stal and Michiei Van den Berghe. Preserving the
archaeological heritage o f the North Sea using innovative data acquisition
techniques and webGIS.....................................................................................................................69
Jongepier lason, under supervision o f Tim Soens and Stijn Tem m erm an. Drowned but
not deserted. Interactions between social and ecological processes o f
estuarine landscapes after flo o d in g . Test-case: the Waasland polders on the
w est-bank o f the River Scheldt (16 th -1 9th c e n tu rie s )............................................................... 70
Jossart Quentin, Rémi A. W attier, Chedly Kastally, Serge Aron, Bruno David, Chantai
De Ridder and T h ie rry Rigaud. Genetic evidence confirm s polygam ous
m ating system in a crustacean parasite w ith m ultiple h o s ts...................................................72
Kemalasari Della, A rim atéa de Carvalho Ximenes, Farid Dahdouh-Guebas and Nico
Koedam. Steps tow ards the use o f the com pactness index to detect
perforation and frag m en tatio n in m angrove fo re s ts ................................................................. 73
Kimeli Am on, Charles Magori, Jared Bosire, Nico Koedam and Stijn Tem m em an.
Sedim entation in response to sea level rise in mangroves o f Mwache Creek,
Mombasa-Kenya: a fie ld and m odeling s tu d y ..............................................................................75
Kungula Makoso Djedje, Sylvestre Géoris, Katrien Q u istho ud t and Farid DahdouhGuebas. A n th ro po g en ic im pacts causing fo re st frag m en tatio n and affecting
the naviga bility o f bolongs in the m angrove forests o f Sokone (Senegal). A
geom atic study su pp orting the m anagem ent o f natural re so u rce s........................................ 76
Lacroix G., X. Desmit, V. Dulière, N. Gypens, C. Lancelot, G. Billen, J. Garnier, V. Thieu,
M. Silvestre, P. Passy , L. Lassaletta , G. G uittard, S. Théry , A. Ménesguen ,
B. Thouvenin, M. Dussauze, M. Mateus, R. Neves, J. Sobrinho, I. Ascione
Kenov, C. Garcia, H. Lenhart, H. Los, T. T ro o st and J. Vander Molen.
Ecosystem Models as Support to Eutrophication Management in the North
A tla n tic Ocean (EMoSEM)..................................................................................................................77
- v iii -
Lescrauwaet Ann-Katrien, Hans Pirlet, Thom as Verleye, Jan Mees and Rudy Herman.
The C om pendium fo r Coast and Sea............................................................................................. 78
Lins Lidia, Katja G uilini, Freija Hauquier, M. André Esteves and Ann Vanreusel. Insights
on the link between surface p ro d u ctivity and benthic com m unities in the
deep s e a ...............................................................................................................................................79
Mascart Thibaud, Gilles Lepoint, François Remy, Sylvie Gobert, Patrick Dauby and
Marleen De Troch. Corsican seagrass d etritus: an opportune shelter or a
copepod Eldorado?.............................................................................................................................80
M atthijs Michiei, Michele Fabris, T. Obata, Stefaan Broos, Gino Baart, A.R. Fernie, Wim
Vyverman and Alain Goossens. The early nitrogen starvation response o f the
diatom Phaeodactylum tric o rn u tu m ............................................................................................. 81
M ortelm ans Jonas, Lennert Tyberghein, Klaas Deneudt and Francisco Hernandez.
Building a d ig ita l Zooplankton sample library as part o f the LifeWatch marine
o bservatory.......................................................................................................................................... 82
Muñiz Pimelia Ángel E., John Hanus, Wendy Bonne and W illem De Moor. JPI Oceans’
p ilo t a ction s......................................................................................................................................... 83
Orellana
Gabriel, Julie Vanden
Bussche,
Lieven Van
Meulebroek,
Michiei
Vandegehuchte, Colin R. Janssen and Lynn Vanhaecke. UHPLC-HR-Orbitrap
mass spectrom etry fo r q uantitative analysis o f lip o p h ilic marine to x in s in
s h e llfis h ................................................................................................................................................ 84
Osuka Kennedy, Melita Samoilys, David Obura, Mare Kochzius and Ann Vanreusel.
Linking the densities o ffis h fu n ctio n a l groups and developm ental stages to
benthic s tru c tu re ................................................................................................................................ 85
Otero Viviana, Katrien Q uisthoudt, Nico Koedam and Farid Dahdouh-Guebas. Looking
fo r mangroves: detection o f the n orthe rnm ost W est-African mangroves in a
non-m angrove dom inated landscape using remote se n sin g ...................................................... 86
Quispe Zuniga Melissa R., Behara Satyanarayana, CyrilPiou,Uta Berger, Hussain
Mohd-Lokman, Ibrahim Sulong and Farid Dahdouh-Guebas. Building an
ecologic-econom ic m odel to im prove silvicultural m anagem ent practices in
Matang (Malaysia)............................................................................................................................... 87
Q uisthoudt Katrien, Loïc Pellissier, Farid Dahdouh-Guebas, Nico Koedam and
C hristophe F. Randin. Lim ited clim atic niche fillin g o f m an grove s.........................................89
Reubens Jan, Ans M outon, Klaas Deneudt, Francisco Hernandez and André Cattrijsse.
Big bro the r is w atching you! An acoustic receiver netw ork to track the
w hereabouts o f fish e s ....................................................................................................................... 90
Santos Cátia, Marta M onteiro, Susana Loureiro, Davy Bosman, Tom Larsen, Liesbeth
de Neve and Luc Lens. Parental feeding behaviour, m ercury accum ulation
and o ffsp rin g fitness: a prelim inary study in the Lesser black-backed guii
(Larus fuscus)......................................................................................................................................91
Schaeck Marlien, Annem ie Decostere, Evelien De Swaef and Wim Van Den Broeck.
Probiotics as biological co ntrol agent in sea bass la rv ic u ltu re ............................................... 92
Schmidt-Petersen Julia, O livier De Clerck and Rachel C ollin. What influences predation
by C oralliophila? Exploring the relationships between corals, sym biotic
zooxanthellae, and corallivorous gastrop o ds..............................................................................93
Scoma A lberto, Ramiro Vilchez-Vargas, Marta Barbato, Francesca Mapelli, Sara Borin,
Daniele D affonchio and Nico Boon. M icrobial piezophysiology: which role fo r
high pressure in oil degradation?................................................................................................... 94
Seghers Stephie, Katrien Q uisthoudt, Farid Dahdouh-Guebas and Nico Koedam.
C om paring m eteorological data from w eather stations and in s itu data
loggers in m angrove areas in South A fric a .................................................................................. 95
- ix -
Seys Jan, Tina Mertens and André C attrijsse. Ocean p hila n th ro p y to feed marine
scientific k n o w le d g e ......................................................................................................................... 96
Sotillo Alejandro, Eric Stienen, Magda Vincx and Luc Lens. C om bining GPS tracking
and stable isotope analysis to predict changes in guii dynam ics...........................................97
Souza Dias Francisco, Simon Claus and Francisco Hernandez. The European Marine
Observation and Data N etwork (EMODnet) central p o rta l........................................................ 98
Speeckaert Gaëlle, Christiane Lancelot, Nathalie Gypens and A lb erto Borges. Study and
m odelling o f DMSP p roduction and its conversion into DMS by North Sea
specific p h yto p la n kto n ...................................................................................................................... 99
Stienen Eric W.M., Peter Desmet, Luc Lens, Hans Matheve, Francisco Hernandez and
W illem Bouten. GPS tags reveal m ovements o f Herring and Lesser Blackbacked Gulls along the Belgian c o a s t......................................................................................... 100
Stock Willem, Kim Heylen, Koen Sabbe, Anne W illem s and Marleen De Troch.
Copepods prom ote nitrogen retention in estuarine sedim ents............................................ 101
Swaleh Khyria, Boaz Kaunda-Arara, Renison Ruwa and Philip Raburu. Ecosystem-based
assessment o f the M alindi-Ungwana Bay prawn fish e ry using ecological
in d ica to rs ............................................................................................................................................102
Taheri Mehrshad, Mateja Grego, Bettina Riedel, Magda Vincx and Jan Vanaverbeke.
Effect o f induced anoxia on nematode densities, vertical d is trib u tio n
patterns and recovery at the G ulf o f Trieste (Northern A d ria tic Sea).................................. 104
T hant Silvy, M atthias Baeye, Frederic Francken, Michael Fettweis, Jaak M onbaliu and
David Van Rooij. Extreme values o f Suspended Particulate M atter
concentration and th e ir relation to wave systems along the Belgian inner
s h e lf................................................................................................................................................... 105
Vafeiadou Anna-Maria, C hariton C hin tiro glo u and Tom Moens. How do marine
nematodes cope w ith extrem e tem peratures and flu ctua tion s? ..........................................106
Van
Cauwenberghe Lisbeth, Ann Vanreusel, Jan Mees and Colin R. Janssen.
M icroplastics... one league under the s e a !...............................................................................107
Van Cauwenberghe Lisbeth, Michiei Claessens and Colin R. Janssen. M icroplastic on
o u r plate, also in our shops..........................................................................................................108
Van de M eutter Frank, Ralf Gyselings and Erika Van den Bergh. O p tim izing the
e stablishm ent o f inland brackish m arshlands: firs t results o f a large-scale
e xpe rim en t and a survey on the invertebrate c o m m u n ity ....................................................109
Van Lancker Vera, M atthias Baeye, Frederic Francken, Dries Van den Eynde, D im itris
Evangelinos, Ilse De Mesel, Francis Kerckhof, Reinhilde Van den Branden and
Lieven Naudts. W orking to g e th e r on innovative m on itoring strategies:
adapting to nature, huge dem ands and grand c h a lle n g e s ...................................................110
Van Lancker Vera, Lies De Mol, Guy De Tré, Denise Maljers, Tine M issiaen,Jan Stafleu,
Dries Van den Eynde and Sytze van Heteren. Exploring o u r marine
geological resources in the fifth dim ension: A b ou t BD voxels, 4D im pact
m odels and u n c e rta in ty ................................................................................................................ 111
Van Tran Thi, Katrien Q uisthoudt, Hai Phan Son, Farid Dahdouh-Guebas and Nico
Koedam. Did sedim ent accum ulation o f 210Pb and 137Cs in mangrove
forests o f Vietnam (Ca Mau Peninsula) respond to sea level rise?...................................... 11 2
Vanaverbeke Jan, Ulrike Braeckman, Cari Van Colen, Katja G uilini, D irk Van Gansbeke,
Karline Soeteaert and Magda Vincx. Ocean acidification affects the benthic
nitrogen cycle in coastal sedim ents: evidence fro m the Belgian Part o f the
N orth Sea.......................................................................................................................................... 11 3
- X -
Vanden Bavière Andreas, Johan Robbens, Filip Volckaert, Sophie Delerue-Ricard,
Geneviève Lacroix and Léo Barbut. Larval dispersal and juve nile dynamics o f
fla tfish in the Southern North Sea.............................................................................................. 114
Vanden Eede Sarah, M ichiei Smits, Annelies Bolle, H endrik Schoukens, Tina Mertens
and Steven Degraer. Beach nourishm ent and the im pact on Natura 2 0 0 0 ......................11 5
Vandendriessche Sofie, Lies Vansteenbrugge, Kris Hostens and Hannelore Maelfait.
Judging je lly fis h : factors influencing the perception on je lly fis h and th e ir
b lo o m s ...............................................................................................................................................11 7
Vandermeersch G., L. Devriese, K. Bekaert, S. Vandendriessche, H. Theetaert,
K. Hostens, J. Robbens. Occurrence o f m icroplastics in brown shrim p on the
Belgian part o f the North Sea...................................................................................................... 11 8
Vandorpe Thom as, David Van Rooij, Henk De Haas and Francisco Javier HernandezMolina. Stratigraphy and palaeoceanography o f a topogra ph y-co ntro lle d
co nto urite d rift system in the Pen Duick area, Southern G ulf o f C a d iz ............................ 11 9
Vanhaecke Delphine, Mika Odido, Jan Mees, Tina Mertens and Peter Pissierssens.
Kenya-Belgium cooperation in the fram e w o rk o f marine sciences....................................120
V anhellem ont Quinten and Kevin Ruddick. Human impacts on coastal suspended
sedim ent concentrations observed w ith Landsat 8 ................................................................ 121
Verhelst Pieterjan, David Buysse, Johan Coeck, Jan Reubens, Magda Vincx and Ans
M outon. Estuarine behaviour o f European silver eel (A n g u illa a nguilla) in the
Scheldt Estuary................................................................................................................................ 122
Verheye M. and C. d ’Udekem d ’Acoz. Deep phylogeny o f the am phipod super-fam ily
E usiroidea......................................................................................................................................... 123
Vermeersch Xavier and Geertrui Vlaemynck. Post-trawling damage and m o rta lity
am ongst brown shrim p (C rangon crangon L.) in the Flemish shrim p fis h e ry .................124
Verm ote ELine, C harlotte Van M oorleghem and Eduardo de la Peña. Performance
com parison o f local and non-local genotypes o f A m m op hila a re n a ria in the
Flemish coast and evaluation o f the effects on a specialist h e rb ivo re .............................. 125
Viaene Karel, Lisette de Hoop, Jan Hendriks, Frederik De Laender and Colin R. Janssen.
M odelling - alternative resource fo r oil risk assessm ent?....................................................126
V oigt Maria, Hichem Gherraz, Uwe G riiters, Nico Koedam and Farid Dahdouh-Guebas.
C om parison o f density estim ators in coastal populations using a m odelling
a pproach.............................................................................................................................................127
Vranken Sofie, Stefanie Dekeyzer, Leen Vandepitte, Simon Claus, O livier De Clerck.
Towards a com pilation o f biological tra it data fo r European m a croa lga e ...........................128
Waumans Filip, Robin H outhoofdt, Bart Vanhoorne, Stefanie Dekeyzer, Aina Trias
Verbeeck, Leen Vandepitte, Klaas Deneudt and Francisco Hernandez. Demo
o f the LifeWatch web services: online data processing to ols fo r b iodiversity
research..............................................................................................................................................129
W illems Tomas, Annelies De Backer, Kris Hostens and Magda Vincx. Epibenthic
com m unities in the coastal waters o f Surinam e..................................................................... 130
Yam am oto Hana Ortega, Stephanie Van de Vreken, Homayoon Kom ijani and Jaak
M onbaliu. Wave m on itoring Broersbank: m easurem ent campaign and
m o d e llin g .......................................................................................................................................... 131
Yazdani Maryam, Ulrike Braeckman, Sofie Derycke, Melanie Sapp, Anne Willems,
Magda Vincx and Jan Vanaverbeke. D irect and ind ire ct effects o f
m acrofaunal fu n ctio n a l d ive rsity and bacterial and archaeal com m un ity
characteristics determ ine benthic nitrogen cycling in coastal marine
s e d im e n ts...........................................................................................................................................132
- xi -
Zervas D im itrios, Kyung Min Lee, Sofie D’H ondt and O livier de Clerck. D iversification
o f Mediterranean Cystoseira (Fucales, Phaeophyceae) using a RAD-Seq
a pproach........................................................................................................................................... 133
APPLICANTS VLIZ THESIS AWARDS MARINE SCIENCES 2013
Briels Nathalie. Bioaccumulatie van organische polluenten in haaien en roggen van de
o ostku st van de VS......................................................................................................................... 136
De Nui Pieter Jan. M orphological changes in the Zwin and Westerschelde estuaries: an
analysis o f historical m a p s ...........................................................................................................137
Mevenkamp Lisa. Selective settlem ent o f deep-sea and in te rtid a l m eiofauna - an
e xperim ental a pp ro ach ................................................................................................................. 140
M ollaert Justine en Sofie Peelman. Experim entele studie van het overslagdebiet voor
steile hellingen en verticale wand m et zeer lage v r ijb o o rd ................................................... 141
Sotillo Alejandro. C onsum ptie van te ru gg o oi door zeevogels inde zuidelijke N o o rd ze e ............... 148
Stock Willem. Het belang van de vergeten schakel: copepoden beïnvloeden de
stiksto fcyclu s................................................................................................................................... 1 50
Van Echelpoel Wout. Micro-CT ais innovatieve visualisatietechniek van m icroplastics in
mariene o rg a n ism e n ......................................................................................................................1 52
Vanhove Brecht. T rofische positie van de invasieve kamkwal M nemiopsis leidyi: een
experim entele aanpak....................................................................................................................1 56
W illems Yves. ‘Aquacalypse Now’ and the end o f fish: an analysis o f instrum ents o f
sustainable fisheries in Europe..................................................................................................... 160
APPLICANTS VLIZ NORTH SEA AWARD 2013
Degraer Steven. Environm ental impacts o f offshore wind farm s in the Belgian part o f
the North Sea: Learning from the past to o ptim ize fu tu re m on itoring
p ro g ra m m e s.................................................................................................................................... 164
Diesing Markus, David Stephens, and John A ldridge. A proposed m ethod fo r assessing
the e xten t o f the seabed sig n ifica n tly affected by demersal fish in g in the
Greater North Sea............................................................................................................................. 169
Hijma Mare. The southern North Sea? Rhine-Thames la n d !................................................................... 170
Reubens Jan. The ecology o f benthopelagic fish at offshore wind farm s - Towards an
integrated m anagem ent a p p ro a ch ............................................................................................. 174
Vanden
Eede Sarah. Im pact o f beach nourishm ent on coastal ecosystems w ith
recom m endations fo r coastal policy in Belgium ......................................................................176
Weijs Liesbeth. Developm ent o f physiologically based pharm acokinetic models fo r the
bioaccum ulation o f persistent organic pollutants in marine m am m als..............................177
- x ii -
ANNUAL VLIZ THESIS AWARDS MARINE SCIENCES 201 3
Every year VLIZ awards tw o marine Master theses. Fundam ental as well as applied marine
researchers in all disciplines o f marine sciences can apply. The prize am ounts to 500 EUR and is
reserved fo r young scientists th a t are graduated at a Flemish university or college fo r higher
education.
The 2013 w inners o f the Annual VLIZ Thesis Award Marine Sciences are:
JEROEN DE WAEGEMAEKER
Artesis Hogeschool Antw erpen,
Dept O ntwerpwetenschappen
Stedenbouw en R uim telijke Planning
fo r the thesis e ntitled:
Klimaatverandering ais motor voor een vernieuwd kusttoerisme?
Potenties van een gecompartimenteerde kuststrook
voor het kusttoerisme
&
JULIA SCHMIDT-PETERSEN
W orking Group Phycology, Ghent U niversity
Krijgslaan 281 S8, 9000 Gent, Belgium
fo r the thesis e ntitled:
What influences predation by Coralliophila?
Exploring the relationships between corals, symbiotic zooxanthellae,
and corallivorous gastropods
-
1
-
Klim aatverandering ais m o to r voor een vernieuwd kusttoerism e?
Potenties van een gecom partim enteerde k u s ts tro o k voor het
kusttoerism e
De Waegemaeker Jeroen
Artesis Hogeschool Antw erpen
Departem ent O ntw erpwetenschappen
E-mail: ieroen.dewaeqemaeker@ qmail.com
De ingezonden m asterproef is niet m ijn eerste onderzoek op de Vlaamse kust. Drie ja a r geleden
studeerde
ik a f ais
ingenieur-architect aan de KULeuven
met een thesis getiteld;
‘in fra s tru c tu re n b u n d e l en kustlandschappen: resoneren, inte rfe re re n , tekenen’. In deze
m asterproef, begeleid d oo r prof. Bruno De M eulder en Maarten Van Acker, werd de kust benaderd
ais infra structu urp ro je ct. Het u itga ng spu nt was om enkele strategische projectvoorstellen voor de
kusttram en K oninklijke Baan te form uleren met het kustlandschap ais to o i en doei. Het was toen
dat de kustverdediging voor het eerst mijn interesse wekte. Dat ja a r werd het Masterplan
Kustveiligheid - in feite een eerste klim aatadaptatieplan voor onze Belgische kust - voorgesteld. De
ze edijk werd onderdeel van de thesis, ik slaagde en begon mijn studies stedenbouw en ruim telijke
planning aan de Artesis Hogeschool Antwerpen.
Ondertussen liep in Vlaanderen reeds een strategische basisonderzoek genaamd CcASPAR. CcASPAR
is een acroniem vo or clim ate change and changes in sp a tia l structures research project. Dit
in te rd iscip lin a ir en interu n ive rsita ir project, gefinancierd d oo r het IWT, ond erzoe kt de gevolgen van
de klim aatverandering op de Vlaamse ruim telijke s tru c tu u r (meer info hierover v in d t u op de
website w w w.ccaspar.uqent.be terug). W erkpakket 5 zoom t daarbij in op twee casestudies; Kempen
en kust. Via ontw erpend onderzoek w o rd t de c o m p le x ite it van de klim a atp rob le m atie k in beide
streken bestudeerd en worden (alternatieve) adaptatiem aatregelen verkend. Ik had het geluk om
aan het ontw erpend onderzoek vo or de kust, een sam enwerking tussen Hogeschool Gent afdeling
landschapsarchitectuur en U niversiteit Gent afdeling M o b ilite it en R uim telijke Planning, te mogen
meewerken.
Gezien de ruim telijke verscheidenheid in klim aatsim pacten en kwetsbaarheid vo or de
klim aatverandering, is het ontw erpend onderzoek naar de kust opgedeeld in drie gevalstudies:
Uzervlakte, ku ststroo k en Vlakte van de Raan. In de Uzervallei w o rd t landschap(splanning) ingezet
ais instru m e nt voor een integraal w aterbeheer van het rivierbekken en de polders. De gevalstudie
Vlakte van de Raan zoekt potenties in zee en probeert het huidige debat o m tre n t de aanleg van
eilanden open te trekken. De ku ststroo k is de zone tussen ku stlijn en snelwegen E40 en AIO . Het
gebied vo rm t de interface tussen zee en land en w o rd t aan een veelvoud van klim aatseffecten overstrom ingen vanuit zee, overstrom ingen vanuit het achterland, v e rz iltin g ,...- blootgesteld. De
overheid is voor deze zone alvast in actie geschoten. De A fdeling Kust stelde het Masterplan
Kustveiligheid op om huidige veiligheidsniveaus (althans voor w at b etreft kustverdediging) to t in
2050 te garanderen. Het CcASPAR project plaatst enkele kritische kanttekeningen bij de
vooropgestelde maatregelen en stelt een nieuwe strategie, het zogenaam de com partim enteren,
voor. Ter inform atie is in d it inschrijvingsdossier een artike l over het com partim enteren bijgevoegd.
Hier vin d t u de kritische bem erkingen op het Masterplan Kustveiligheid en de basisgedachtes achter
het com partim enteren terug.
H uidige kustverdediging; hold-the-line
CcASPAR-project; com partim enteren
De com partim enteringsstrategie kan kortw eg samengevat worden ais een ‘dow nsca lin g ’ van de
klim aatproblem atiek. Want hoewel de klim aatverandering een m ondiaal gegeven is, hangt de
precieze im pact steeds samen met zowel het fysisch systeem ais het ruim teg eb ruik. W illen we
- 2 -
lokaal technologische en ruim telijke maatregelen in balans brengen, dan m oeten we deze
verscheidenheid kennen. Binnen het CcASPAR onderzoek gebeurde deze inschatting aan de hand
van GIS-analyses. Voor diverse sectoren werd met de beschikbare GIS-data en inschatting gem aakt
van de kwetsbaarheid en de waardering van het ru im teg eb ruik in elk com partim ent. Een GIS-matige
inschatting maken van toerism e en recreatie was niet m ogelijk. Deze sector beschikt z e lf (voorlopig)
niet over GIS-data en analyses. Een studie maken van toerism e en recreatie op basis van andere
datasets, bijvoorbeeld de natuur- en landschapswaarde, bleek te com plex. Ook kw alitatieve studies
naar de ruim telijke verscheidenheid zijn (quasi) onbestaande. Het lu ik toerism e en recreatie zijn
daarom in de analyses vo or CcASPAR eerder dun uitgevallen.
Daarom besloot ik m ijn m asterproef - ik com bineerde het CcASPAR onderzoek m et m ijn laatste jaa r
studeren - in te zetten om d it onderdeel verder u it te werken. Basisvragen voor de thesis zijn;
‘Waarom is het kusttoerism e een belan grijk aspect binnen de klim aatadaptatie?’, ‘ Hoe w o rd t onze
huidige kust beleefd en gewaardeerd?’, ‘ Hoe verscheiden is het Belgische kusttoerism e?’ en ‘ Kan de
com partim enteringsstrategie de toeristische ontw ikkeling e n een kw aliteitsvolle im puls geven?’.
Deze focus op kusttoerism e g af mij de v rijh eid om op de eerste vraag een haarfijn antw oord te
bieden. In discussies met andere planners en ontw erpers ervaar ik vaak een m isprijzen vo or de
Vlaamse kust. Het is ongetw ijfeld een fascinerend gebied maar velen w illen het toerism e er anders;
een duurzam e kust, een vernieuwde en landschappelijkere aanpak, enzomeer. Onder meer de
Vlaams Bouwmeester roept op to t een breed debat over de kust. Voor elk van deze ideeën valt
uiteraard iets te zeggen maar waarom zouden we e ig e n lijk iets veranderen? De econom ische m otor
sp u tte rt niet; toeristen blijven in grote getale afzakken naar de Belgische kust. Waarom dan z o ’n
ingrijpende plannen form u le re n en doorvoeren?
VERSTEDELIJKING?
% stedelijk ontw ikkelingen In de
io n e binnen 10km van de kustlijn
HARDE KUSTLIJN?
% versterkingen van de kustlijn
(zeewering en artificiële stranden]
■11 ,V
li. n
Klim aatverandering biedt een antw oord. Ais we vandaag niet ageren, zijn we
morgen erg kwetsbaar voor de opw arm ing van de aarde. Dit g eldt voor de
lokale bewoner, de havenarbeider, de plaatselijke boer EN voor de toerist.
Die laatste is trouw ens extra kwetsbaar voor de klim aatsim pacten (zie
hoo fdstuk 1). Toeristen wonen met zic h t op zee maar ze zijn ook de eerste
slachtoffers van een (super)storm . Bovendien is toerism e in belangrijke mate
ve ra ntw o orde lijk voor de huidige kwetsbaarheid (zie h oo fdstuk 2). Met het
toerism e ais m oto r is de natu urlijke zeewering - de duinengordel- vervangen
d oo r een zeedijk; van brede interface naar scherpe grens tussen zee en
land. De n atuurlijke capaciteit om ons aan het veranderde klim aat aan te
passen, gebruikm akend van de landschappelijke dynam ieken, is zo in
belangrijke mate uitgeschakeld. En onder d ru k van het toerism e is onze
blo otstelling spectaculair gegroeid. Vanuit twee badplaatsen hebben
toeristische ontw ikkeling e n zich overheen 67 km ku ststroo k uitgespreid.
Waar vroeger slechts enkele duinboeren en vissers leefden, ontw ikkelde zich
de A tla n tic Wall. Een lijnstad waar meer dan 200.000 inwoners wonen en die
in de zom er 300.000 toeristen en 250.000 dagjestoeristen aantrekt. Een
harde kust die - veel meer dan onze b u u rre g io ’s - ve rste d e lijkt is net
om w ille van het kusttoerism e (zie fig u u r links).
Beleid voor het kusttoerism e en de klim aatverandering (waaronder
kustverdediging) zijn bijgevolg to t elkaar veroordeeld. Elk plan in het licht
van klim aatadaptatie zal een effect hebben op de toeristische ontw ikkeling
en vice versa. In een goed plan vorm en beide aspecten twee handen op één
buik. Hierin lig t volgens m ij een belangrijke taak weggelegd voor de
ruim telijke planning. Is het streven naar w in-w insituaties niet een kenm erk
van ruim telijke planning? Een éénzijdig beleid zal geenszins erg vruchtvol
zijn. Denken we maar aan het Masterplan Kustveiligheid dat vooral wenst
aan te tonen dat de invloed op het toerism e beperkt zal zijn. Een strategie
waar men zich grote vragen bij kan stellen, vooral op langere te rm ijn.
H oofdstuk B intro du cee rt het com partim enteren in het verhaal. Op deze
strategie zal ik in deze leesw ijzer niet dieper op ingaan. Ik verm oed dat de
ta ctiek in het bijgevoegde A-plus artike l k o rt maar afdoende w o rd t
uitgelegd. In feite m aakt d it h oo fdstuk geen deel u it van m ijn m asterproef
maar is het een (eerste) neerschrijven van het CcASPAR-onderzoek. Ik heb
o p basis van gegevens EUROSION
getw ijfeld
om d it onderdeel
niet mee in te zenden vo or de
aanm oedigingsprijs maar om w ille van de leesbaarheid en de volledigheid heb ik het toch in d it
dossier opgenom en.
Nu we weten waarom we vanuit ruim telijke planning op de kust en het kusttoerism e moeten
ingrijpen, is het n oodzakelijk om de huidige ontw ikkeling e n tegen het licht te houden. Wat is nu
precies de kernwaarde van de Vlaamse kust en waar loo pt het mis? H oo fd stuk 4 schetst daartoe de
historische evolutie van onze kust. Het is een verhaal dat reeds vaker is verteld. In deze m asterproef
w o rd t de geschiedenis gestructureerd aan de hand van drie strategische ruim tes: strand, duin en
d ijk. Het zijn drie zones die elk een rol spelen in de kustverdediging en die reeds vanaf het prille
begin een sterk toeristisch en recreatief (m ede)gebruik kennen.
Deze studie van de geschiedenis to o n t een zekere c o n tin u ïte it aan. De hedendaagse to e ris t verschilt
w einig van zijn voorgangers. Net ais de burgerij u it de negentiende eeuw en de hogere
arbeidersklasse van het interbellum , fla ne ert de moderne bezoeker over de d ijk, (zonne)baadt hij op
het strand en speelt hij in de duinen. Het zijn sterke belevingen die ook nieuwe ontw erpen en
ontw erpend onderzoeken inspireren. Na twee ja a r onderzoek op de Belgische kust heb ik heel w at
schetsen en plannen verzam eld en in vele ontw erpen komen de eerste kernwaarden en -belevingen
van de kust terug. De oude postkaarten lijken de moderne ontw erpers te inspireren. Het is deze
verzam eling aan beelden, zowel historische en hedendaagse fo to ’s ais ontw erpschetsen, die de
kern van de onze kust visualiseren.
In h oo fdstuk 5 w o rd t deze evolutie in een internationaal perspectief gezet. De intro du ctie van het
concept levenscyclus is een poging om het belang van ruim telijke planning in de o ntw ikkeling van
toeristische streken te duiden. De levenscyclus b esch rijft een standaardverloop vo or een
toeristische streek; 1) een exploratiefase, 2) een ontw ikkelingsfase, B) een consolidatiefase, 4) een
stagnatiefase en 5) de - onverm ijdelijke? - afkalving. De toepasbaarheid van d it concept op de
Vlaamse kuststreek is betwistbaar. Onder meer de nabijheid, het hoge aantal tweede verblijven en
de pensioenm igratie m aakt onze kust uniek? De evolutie zoals ze door de levenscyclus w o rd t
beschreven is bovendien te sterk vereenvoudigd. Ze m aakt geen onderscheid tussen de
verschillende m arktsegm enten zoals korte en lange vakanties, dagjestoeristen en types
overnachtingen.
Over de intro du ctie van het concept levenscyclus is aardig gediscussieerd op de thesispresentatie.
Dat was ook één van m ijn aanvankelijke doelen ais student; een debat u itlokken over het toerism e
aan de kust. Voor zoverre dat uiteraard m og elijk is binnen een m asterproef. Het
levenscyclusconcept vo rm t in de m asterproef niet alleen een aanleiding om de huidige
ontw ikkeling e n kritisch te benaderen. Het begrip introduceert ook de rol van ruim telijke planning in
toerism e. Eens we het standaardpatroon kennen, kunnen we hierop anticiperen; ruim telijke
planning ais strategie om stagnatie en terugval te voorkom en. Ais uitgeleide w o rd t hierbij op de
beleidsplannen vanuit toerism e ingegaan. W esttoer, het verzelfstandigd p ro v in cie b e d rijf voor
toerism e, w ijs t op de nood aan een gebalanceerde aanpak; een strategie w aarbij sterkte punten
verder uitgebouw d worden en nieuwe ontw ikkeling e n gestim uleerd worden.
s tra n d
stag n a tie ?
c onsolidatie
o n tw ik k e lin g
e x p lo ra tie
Evolutie van het Belgische kusttoerism e volgens het concept levenscyclus en de im pact ervan op strand,
d ijk en duin.
4 -
Kan het com partim enteren een dergelijke gedifferentieerde aanpak bewerkstelligen? H oofdstuk 6
trach t deze vraag te beantwoorden via ontw erpend onderzoek. Daartoe w o rd t eerst de huidige
ruim telijke verscheidenheid van het kusttoerism e onderzocht. Het oorspron kelijke doei was om de
waarde van de kustbeleving te achterhalen door het opstellen van een kaartenatlas. Het karteren
van relevante elem enten om de streek in de vingers te krijgen. Maar het toerism e bleek -le tte rlijk - te
com plex om in kaartlagen te vatten. De ontw erpvaardigheden werden daarom ingezet op zoek naar
een andere leesbare representatie. De kennis u it de literatuu r- en ontwerpanalyses werden
sam engebracht in diagram m en. Per badplaats, duingebied en samenhangend poldergeheel werd
z o ’n diagram opgesteld om de waarde van kustbeleving te visualiseren. Zoals elke ontw erpschets
staan ook deze diagram m en open vo or discussie. Welke aspecten nemen we op en w elk gew icht
krijgen ze? De ju is te opm aak van deze diagram m en vraagt om uitgebreid onderzoek w aarbij ook
het brede publiek en bevoorrechte actoren worden betrokken. Deze m asterproef is een eerste test.
Met behulp van de resultaten werd dan alsnog een kaart vo or de ruim telijke verscheidenheid van
het kusttoerism e opgesteld. Deze samenvattende fig u u r to o n t alvast dat gebieden m et een sterke
dijk- en polderbeleving erg verspreid voorkom en. De duinen daarentegen worden voorna m e lijk aan
de W estkust sterk ervaren.
RUIMTELIJK VERSCHEIDENHEID KUSTTOERISME
ANALYSE K USTSTR O O K
------------- WEGEN
A N A L Y SE K U S T L IJN
:
............... SPOORWEGEN
VAARWEGEN
STERKEDUINBELEVING
A
ZWAKKE DUINBELEVING
*« 5*185 STERKE POLDERBELEVING
BEBOUWING
STERKE DIJKBELEVING
SLIKKE EN SCHORRE
ZWAKKE DIJKBELEVING
STERKEDUINBELEVING
ZWAKKE DUINBELEVING
■
■
STERKE DIJKBELEVING
ZWAKKE DIJKBELEVING
K aartfiguur - ru im te lijke verscheidenheid van het Belgische kusttoerism e.
T ot slot zoekt de m asterproef - bij w ijze van eerste vingeroefening- naar lokale synergieën tussen
klim aatadaptatie en toeristische o ntp lo o iin g . A llereerst w o rd t nagedacht hoe bestaande systemen
(dijk, duinen en polders) verder kunnen worden uitgebouw d. De o ntw ikkeling van een getrapte d ijk
bijvoorbeeld ve rd ed igt de ku stlijn tegen steeds hogere golven te rw ijl het ook een im puls geeft aan
het toeristisch en recreatief m edegebruik. Daarna werden ook enkele eerste alternatieve concepten
o pgelijst: A tla n tic Wal(l), w aterlandschap, inlaatpolder, w aterdunen en d ijkp ark. Het zijn ideeën die
reeds in andere ontw erpende onderzoeken werden bestudeerd en waar de klim aatsim pacten en de
fysische dynam ieken een plaats krijgen in de verdere o ntw ikkeling . Zo stapt het concept A tla n tic
Wal(l) a f van de klassieke onovertopbare dijk. In plaats daarvan geeft ze deze (occasionele)
overstrom ingen va nu it zee een plaats en bereidt ze het ruim te g e b ru ik hierop voor.
A lternatieve concepten van rechts naar links; A tla n tic Wal(I), waterlandschap, inlaatpolder, w aterdunen, d ijkp a rk.
Vervolgens werd de kennis va nu it het CcASPAR project (m et name ‘Waar doen welke
klim aatproblem en zich voor?’ en ‘Waar zijn er kansen om deze im pacten ruim te te geven?’) en de
kennis binnen deze m asterproef (‘Waar kent de huidige toeristische beleving een sterke
waardering?’) sam engebracht. Voor elke badplaats, duingebied en polder aan de kust werd
nagegaan o f de klassieke en alternatieve concepten een antw oord bieden. Deze analyse to o n t alvast
aan dat om w ille van de grote verscheidenheid in zowel klim aatproblem en ais kusttoerism e er steeds
andere scenario’s favorabel zijn. Er is niet één concept dat d om in e ert maar allem aal vinden ze - in
meerdere en mindere mate - een toepassing aan de Vlaamse kust. Het idee van één zaligm akende
kustverdediging en bijhorend type kusttoerism e kan en m oet verlaten worden.
Maar m aakt d it planning op schaal van de gehele kuststreek overbodig? Het ontw erpend onderzoek
w ijs t alvast op het belang van het (nieuwe) d ijkenpatroon. Mits aandacht voor de samenhang en
leesbaarheid kunnen deze infra structu re n uitgroeien to t een bindend recreatief netwerk. Een link
tussen alle verschillende com partim enten die ervoor z o rg t dat de Vlaamse kuststreek één
toeristische streek b lijft.
!»
Sr
!#
Collage - gecompartimenteerde kust bij stormen.
44
JBt
Collage - recreatief medegebruik van de dijken.
De thesis tre k t to t slot een aantal algemene besluiten. A llereerst m aakt de probleem stelling
d u id e lijk dat kusttoerism e en klim aatadaptie vragen om één integrale benadering. Geen enkel
adaptatieplan voor de kust zal slagen ais het niet op de verdere o n tp lo o iin g van het kusttoerism e
ingaat en vice versa. Verder to o n t de thesis aan dat de beleving van de Belgische kust verscheidener
is dan we vaak aannemen. Er zijn wel d e g e lijk verschillen langsheen de 67 kilom ete r lange kustlijn
en we zullen deze verschillen bovendien goed in de vingers moeten krijgen. Enkel zo kunnen we
zoeken naar de p laatselijk beste adaptatiestrategie. Niet één standaardm aatregel maar een breed
scala aan m ogelijkheden is nodig. Enkel zo brengen we een einde aan de continue lijnstad. Gedaan
met de A tla n tic Wall en weg m et de huidige ku stlijn ! Laten we waardevolle elementen recupereren
en plaats maken vo or nieuwe o ntw ikkelingen. De kust ais com positie duinen, polders, badplaatsen,
w aterlandschappen, d uinw ijken, inlaatpolders, slikken, schorren, vakantiedorpen,...
Het mag d u id e lijk zijn dat ik de kuststreek een warm hart toedraag. Ik wens haar bij deze een
interessante to eko m st toe. Ik hoop dat er w eldra een breed debat over onze kuststreek (en het
toerism e in het bijzonder) losbreekt. Ze kan alle ideeën en reflecties best gebruiken.
f TTYTT'i
'JiI l l i n i u m
Karikatuur - het huidige toerisme (Steven Wilsens, 1962).
Karikatuur - toerisme in een gecompartimenteerde kust (eigen
bewerking).
6 -
What influences predation by Coralliophila? Exploring the
relationships between corals, sym biotic zooxanthellae, and
corallivorous gastropods
Schmidt-Petersen Julia
W orking Group Phycology, Ghent University, Krijgslaan 281 S8, 9000 Gent, Belgium
E-mail: iulia.schm idtpetersen@ qm ail.com
Coral feeding gastropods can occur in high num bers and may have severe impacts on reefs, but
th e ir ecology is still poorly understood. This study explores which intraspecific variations o f corals
(such as depth, color m orph and associated zooxanthellae strain) influence predation by
corallivorous gastropods. Samples, field data and pictures o f corals and snails were taken in reefs
around Bocas del Toro, in the Caribbean region o f Panama. Zooxanthellae were identified by
Denaturing Gradient Gel Electrophoresis (DGGE), a fte r DNA was obtained from corals w ith a recently
developed m icro-invasive technique, using a syringe w ith a blunted needle, and was herein proven
to be applicable fo r a variety o f coral species. The study found th a t (1) corals o f the M onastraea
a n n u la ris com plex th a t incorporate w hite structures (‘w hite layer’) o f unknow n origin in th e ir tissue
are less often infested by C oralliop hila abbreviata. (2) When associated w ith one rare sym biont
strain o f clade B (8%), A cro po ra cervicornis bears higher densities o f C. caribaea than if associated
w ith the other, more com m on strain o f clade A (92%). General occupation rates o f A. cervicornis in
Bocas del Toro are low fo r C. a b b re via ta (4%) and high fo r C. caribaea (63%) com pared to other
locations in the Caribbean. (3) C. caribaea d iffers from its congener by not undergoing sex change,
a less destructive feeding strategy by prudent sessile feeding, which does not cause open lesions,
and seem ingly rem aining longer on the same coral polyp. T ogether w ith the known fact th a t it
tran sm its white-band-disease, the study suggests th a t high abundances o f C. a b b re via ta on
A. cervicornis are more alarm ing than o f C. caribaea, which should be addressed in fu rth e r studies.
7 -
ANNUAL VLIZ NORTH SEA AWARD - 201 3
Each year the Flanders Marine Institute (VLIZ) awards a scientific prize to fo ste r innovative
fundam ental or applied research on the structure and fu n c tio n in g o f the North Sea ecosystem, w ith
emphasis on coastal and estuarine areas o f the Southern Bight and the Channel. The prize is
awarded to a researcher (or a research team) w orking and residing in a co u n try bordering the North
Sea. The prize am ounts to 1000 EUR and is indivisible. It is granted to reward a recent original
scientific co n trib u tio n , preferably having relevance to the sustainable m anagem ent o f the area
concerned. Studies pertaining to the bio dive rsity o f the local ecosystem are equally welcomed. The
c o n trib u tio n has to be o f postgraduate or postdoctoral level.
The Annual VLIZ North Sea Award 201 3 is awarded to:
A
n o u k de
Br auw ere
Université catholique de Louvain
Institute o f Mechanics, Materials
and Civil Engineering (IMMC)
Louvain-la-Neuve
fo r h e r scientific c o n trib u tio n e ntitled:
Multi-disciplinary/scale modeling of the Scheldt Estuary
and tidal river network
(a collection of articles from 2009 to today)
- 9 -
M ulti-disciplinary/scale m odeling o f the Scheldt Estuary and tidal
river netw ork (a collection o f articles from 2009 to today)
de Brauwere A nouk
Université catholique de Louvain, Institute o f Mechanics, Materials and Civil Engineering (IMMC), 4
Avenue G. Lemaître, Bte L4.05.02, B-1348 Louvain-la-Neuve, Belgium
E-mail: anouk.de brau we re@uclouvain.be
From 2007 to today, A n ou k de Brauwere has been the d riving force behind several innovating
m odelling developm ents w ith applications to the Scheldt Watershed. Functioning as a bridge
between hydrodynam ica! m odellers at UCL and tw o teams o f environm ental expe rim en talists at VUB
(metals) and ULB (fecal bacteria), she coordinated the im plem entation o f a m ulti-disciplina ry, and
multi-scale reactive tra n sp o rt m odel to study environm ental questions in the Scheldt Basin. The key
concept o f th is study was ‘ in te g ra tio n ’: integ ra tion o f the necessary m u lti-d isp lin a ry knowledge
(hydrodynam ics, com p uta tio na l flu id mechanics, m icrobiology, (geo)chem istry), but also the spatial
integration o f m orph olo gica lly and dynam ically d is tin c t regions, resulting in a single model
representing the whole tid a l continuum from Ghent to the North Sea. Thanks to th is integrative
nature, the m odel has a unique potential to study processes and concentrations at the basin-scale,
i.e. e x p lic itly including all forcings. This offers possibilities not o nly to better understand the
processes and th e ir effects, but also to assess the im pact o f hypothetical fu tu re (managem ent or
accidental) scenarios fo r the whole Scheldt Watershed and the North Sea.
Three main study subjects were studied so far:
1. Hydrodynamica! modelling and timescales for water transport
This new model was b u ilt using the general architecture o f the Second-generation Louvain-la-Neuve
Ice-ocean Model (SLIM, w w w .clim a te .b e /slim ). The specificity o f th is m odel is th a t it uses the fin ite
elem ent m ethod to solve the governing equations, which allows fo r the use o f unstructured meshes
fo r the spatial discretisation o f the dom ain. An unstructured mesh has a resolution th a t can greatly
vary over the dom ain, i.e. in sub-regions o f interest or subject to more com plex dynamics the
resolution (and thus the com putational e ffo rt) can be increased compared to o the r areas. This
im plies a great fle x ib ility th a t has unique advantages fo r m ulti-scale/physics problem s. In the case
o f the Scheldt, th is fle x ib ility has enabled the integration o f the upstream tid a l river netw ork, the
Scheldt Estuary as well as the N orth-w estern European C ontinental Shelf in one single model. The
large marine part facilitates a more accurate sim ulation o f the tides or storm surges as th ey enter
the Scheldt Estuary. Yet, as the mesh is less resolved in th is large part o f the dom ain (grid size ~
50 km com pared to a resolution down to 60 m in the estuary), the com putational cost is only
doubled compared to a situation where o nly the Scheldt Estuary and the tid al rivers would be
included.
A fte r having validated the hydrodynam ica! m odel (de Brye et al., 2010), the m odel was not yet
practical fo r environm ental applications. In th is form , the inform a tion is s till very com plex (fields
varying spatially and te m p o ra lly at a high resolution) and hence d iffic u lt to use fo r diagnostic
purposes. Therefore, it is useful to derive diagnostic variables which sum m arize some o f the main
tra n sp o rt features present in the com plex raw hydrodynam ica! outputs. This is the general
m otivation behind the use o f tim escales like w ater residence tim e and w ater age, which are often
used in b io log ica l/ch em ical/g eo lo g ica l studies to express the tim e spent by w ater in a given dom ain
which
can
then
be
conveniently
com pared
to
o the r
tim escales
of
more
b io log ica l/ch em ical/g eo lo g ica l relevance. We com puted these tim escales fo r the Scheldt Estuary,
com bining rigorous theoretical form ulas w ith the com plex hydrodynam ica! m odel, such th a t we can
be co nfid en t th a t th ey integrate all relevant physical processes (tim e-varying residual current, tides,
tu rb u le n t diffusion).
The d e fin itio n o f the residence tim e is the tim e th a t w ill be spent by a given w ater parcel in the
estuary u ntil it leaves it fo r the firs t tim e. According to th is d e fin itio n , it is clear th a t the residence
tim e is both variable in space (as it depends on where the w ater parcel is at the m om ent the tim e
m easurem ent is started) and tim e (since it w ill depend on the actual hydrodynam ica! co nditions at
the in itia l or release tim e). Therefore, in a firs t study we com puted the residence tim e fo r 13 boxes
in the estuary (spatial variability) and fo r d iffe re n t in itia l tim es (tem poral variability) (de Brauwere et
al., 201 la).
-
10
-
Great.
Britain
continental
Europe
Bath
Canai,
Port of
Antwerp
docks
mouth
U l IC I IL
Durme
Terneuzen
Canal
upstream
estuarine
limit
Scheldt
D ender
V
' Dyle
JOeine
Nete
Grote
Nete
Senne
50.93
The spatial variation was a pp ro xim a tely as expected, i.e. m onotonically decreasing tow ards the
m outh - except th a t fo r the m ost upstream box the residence tim e was close to zero. A t firs t, this
may seem co un ter-in tu itive but in fact it is in line w ith the d e fin itio n : close to the upstream
boundary o f the estuary the w ater w ill also q uickly ‘ leave the estuary fo r the firs t tim e ’, due to the
tides periodically pushing the w ater upstream . Obviously, th is is not consistent w ith the em pirical
meaning generally a ttrib u te d to the residence tim e: it is supposed to express the to ta l exposure o f
a w ater body in a dom ain. In order to account fo r th is generalisation an alternative tim escale has
been defined: the exposure tim e. When com puted fo r the IB boxes in the Scheldt Estuary, the
exposure tim e in the m ost upstream box is indeed the highest, and in any box it is higher than the
respective residence tim e.
To investigate the tem poral va ria b ility o f the residence and exposure tim e, we com pared the
tim escales com puted fo r initia l tim es in w in te r and summ er, and fo r each season at high and low
tide. As expected, the tim escales are longer in summ er, due to the lower upstream river discharge.
-11-
Equally expected was the fact th a t at low tide the tim escales were longer than when starting at high
tide - because at low tide the w ater w ill firs t be pushed up the estuary. However, it was to ta lly
unexpected to fin d th a t the difference between the high and low tide tim escales were so large: up
to alm ost 20 days. In o th e r words, at the m ost dow nstream box, the exposure tim e o f w ater parcels
‘ released’ at a 6 hour interval varies between 9 (start at high tide) and 28 days (start at low tide)!
These results illustrate th a t the seem ingly simple concept o f residence tim e hides several subtleties
th a t are often not considered in applications, but may be o f sign ifican t im portance. These
observations m otivated us to fu rth e r refine th is study. A firs t refinem ent consisted o f com puting the
‘ partial exposure tim e s ’ o f the IB estuarine boxes, i.e. the to ta l tim e spent in each box, instead o f
in the whole estuary. Doing th is fo r w ater in itia lly in each box at a tim e, we obtained a ‘connectivity
m a trix ’, relating the initia l position o f w ater w ith the tim e it spends in each box. T his inform a tion is
nothing but a sophisticated sum m ary o f the com plex underlying hydrodynam ics, b ut now it is much
more useful fo r applications, e.g. to q uickly assess the im pact o f an accidental p o llu tio n event
somewhere in the estuary on the d iffe re n t sub-regions o f the estuary, or to evaluate how long w ater
stays in subregions known to be favourable fo r the grow th o f a certain species.
In a subsequent refinem ent e ffo rt, we increased the resolution o f the com puted residence and
exposure tim e, such th a t th e ir value is now known fo r every m odel grid cell and m odel tim e step (de
Brye et al., 2012). This is appealing because it provides actual ‘ m ovies’ o f the tim escales varying in
tim e and space. However, the results are again too com plex to be easily usable fo r diagnostic
applications. The tidally-averaged pictures reveal th a t the residence and exposure tim es e x h ib it
su rp rising ly little lateral variation, i.e. the lo n g itu d in a l trend observed w ith the 13 boxes is relatively
accurate. In contrast, there is great spatial heterogeneity in the tem poral va ria b ility associated w ith
the tim escales, resulting fro m a com plex interplay o f bathym etry and w ater discharge.
Besides th is detailed study o f the residence and exposure tim es, the w ater age was also
investigated. As opposed to the firs t tim escales, the age is defined as the tim e since a given w ater
parcel has entered the estuary. Again, the age varies in space and tim e, but it is also dependent on
the ‘entrance’ th ro u g h which the w ater entered. In o th e r words, fo r each d iffe re n t w ater source, a
d iffe re n t age can be defined. In the case o f the Scheldt Estuary, a d is tin ctio n was made between
w ater com ing fro m upstream (freshwater), fro m dow nstream (sea water) and from lateral inputs like
canals and harbour locks.
With the above tim escale studies in the Scheldt Estuary, it has become a benchm ark application. For
instance, one recent study illustrated the m eaning o f another tim escale fo r w ater renewal, the socalled ‘ influence tim e ’, again on the Scheldt Estuary (Delhez et al., in review). New ongoing w ork
consists o f com puting yet another new tim escale, the ‘ partial age’ (a generalisation o f the age
concept), in the Scheldt Estuary.
2. Modelling Escherichia coli concentrations as an indicator of fecal pollution
Due to its intensive agriculture, high concentration o f in d u stry and large population density, the
Scheldt Watershed is subject to sign ifican t p ollutio n pressure. Discharge o f wastewaters or ru n -o ff
loaded w ith animal or human fecal m aterial degrades the m icrobiological w ater quality, i.e.
increases the risk o f having m icrobial pathogens present in the natural surface water. Because these
pathogens are too diverse, and often present o nly at very low concentrations, it is not feasible to
system atically m o n ito r all th e ir concentrations. Instead, it has been decided to measure the
concentration o f a small num ber o f so-called ‘fecal ind icato r bacteria’, o f which Escherichia coli
(E. coli) is one o f the m ost im portant. Its concentration in the Scheldt Watershed has been
m onitored in 2007-8 by colleagues at the ULB, but the results were so variable in tim e th a t they
were d iffic u lt to interpret. It is well known th a t E. coli concentrations can vary over orders o f
m agnitude in natural systems, but the possible causes in the case o f the Scheldt were too num erous
(water discharge, upstream inputs, wastew ater trea tm en t plant inputs, interaction w ith sediment,
tides, tem perature effect) to disentangle them em pirically. If we could o nly sim ulate all these effects
in a single model, we m ig ht be able to q u a n tify th e ir relative im portance... So, an E. coli m odule was
added to SLIM.
A firs t model considered only the tid al part o f the Scheldt Basin, and represented the bacteria as a
single pool (de Brauwere et al., 2011b). Yet, the results were already quite interesting. Indeed, it
appeared th a t the inputs due to the w astewater trea tm en t plants, as well as the tem perature effect
were negligible to explain the observed variability. In contrast, the w ater entering the tid a l dom ain
from upstream was already highly polluted, such th a t it to a great e xten t determ ined the levels
observed in the tid al river. This was especially the case fo r the w ater com ing fro m Brussels and
entering the tid al Scheldt via the Zenne, Dijle and Rupel. In com bination w ith the tid al m ixing
action, these h ighly concentrated upstream (and side) inputs caused greatly varying concentrations
- 12 -
in the Scheldt. Downstream o f the main tribu taries, the gradual decay o f the bacteria and
continuous d ilu tio n results in a steep decrease o f the E. coli concentrations dow nstream o f Antw erp.
Close to the estuary m outh, the bacteria have alm ost disappeared, and the estuary has thus
e ffectively operated as a cleaning filte r.
In a second m odel, we fu rth e r extended both the geographical dom ain and the representation o f
the bacteria pools. By coupling SLIM (tidal rivers + estuary + sea) w ith an ecohydrological m odel o f
the upstream river catchm ent (Ouattara et a i, in press), we e ffectively integrated the com plete
Scheldt Watershed in a single sim ulation (de Brauwere et a i, 2014). Instead o f using these tw o tools
as com peting models, each o f them was used in the dom ain fo r which it was o rig in a lly designed and
clearly o u tp erfo rm s the o the r m odel. This resulted in a unique coverage o f the whole Scheldt lan dsea continuum fro m the source all the way to the North Sea. As the firs t m odel showed the
im portance o f the upstream rivers (and especially the Brussels area), th is integration allowed to
include all E. coli sources e xplicitly. In addition to the geographical m odel integration, we fu rth e r
refined the m odel by d ividing the bacteria pool in free -floa ting bacteria and those attached to
particles. While the firs t are transported along w ith the water, the latter are also subject to settling
and resuspension processes. To e x p lic itly represent these processes, a new suspended sedim ent
m odel has been developed w ith in the SLIM architecture (Gourgue e t a i, in press). The results o f this
second model study confirm the previous observation on the im portance o f the tides, and the weak
effect o f the wastewater trea tm en t plants in the tid a l part. Besides, th ey suggest th a t the sedim entrelated processes are actually not essential to reproduce the median E. co li concentrations along the
Scheldt, nor the observed va ria b ility at a given location. Nevertheless, the e x p lic it d istin ction
between free and attached bacteria increases the insig ht in the system and offe rs more
interpretatio n possibilities. As an illu stratio n o f the potential o f th is new m odelling tool, we also
perform ed tw o sim ulations considering extrem e (w orst case and best case) situations o f Brussels
wastewater management. The effect o f both scenarios is clearly observable all the way to Antw erp.
Several side-studies were also perform ed related to the £. coli m odel in the Scheldt. These studies
range from sem i-theoretical considerations on the param eterisation o f the settling flu x (de Brauwere
and Deleersnijder, 2010), establishing where and when new w ater q u a lity samples should be taken
in ord er to reduce the model uncertainty m ost (de Brauwere e t a i, 2009), derivation and
com putation o f the age associated to the bacteria (M atton, 2012), to the p ublication o f an
exhaustive literature review o f the e xistin g m odels fo r fecal ind icato r organism s in natural surface
waters (de Brauwere e t a i, in press).
3. First steps towards modelling metal spéciation
Besides m icrobiological w ater quality, SLIM could also be extrem ely useful fo r the study o f other
pollutants. Especially its large dom ain, and its a b ility to provide h ighly resolved (both spatially and
tem porally) o u tp u ts makes it an interesting to o l fo r risk assessments. Therefore, we started to build
a new SLIM m odule to allow the sim ulation o f dissolved and particulate metals (Elskens et a i, in
review).
By m erging the long-term data records collected by VUB, ULB and VMM, em pirical fu nctio ns were
derived, relating the to ta l metal concentration to environm ental variables (salinity and suspended
sedim ent concentration). This means th a t if SLIM sim ulates these environm ental variables, we can
reconstruct or predict the metal concentration at each location and each tim este p o f the sim ulation.
A second em pirical fu n ctio n was estiblished linking the metal p a rtitio n in g co efficie nt (i.e. the ratio
between particulate and dissolved metal concentration) to environm ental variables. A pplying this
fu nctio n to the SLIM o utp uts and the reconstructed metal concentrations then allowed producing
high-resolution fie ld s o f dissolved and particulate metal concentration. This means th a t SLIM can be
used to produce ‘ m ovies’ o f dissolved and particulate metal concentrations, allow ing in fin ite ly more
detailed analyses than based on d irect p oint m easurem ents alone. This being said, the lim ita tio n o f
th is approach lies in the em pirical fu nctio ns, which are only valid w ith in th e ir calibration dom ain. In
o the r words, although th is com bined model is already a sign ifican t step forw ard, it cannot be
tru s tfu lly used fo r scenario evaluations or even predictions fo r periods outside the one covered by
the calibration dataset (1980-2010). Therefore, we now focus on the developm ent o f a fu lly
m echanistic metal module.
Conclusion
The cited w ork has obviously been produced by a team o f researchers. Nevertheless, it is the m erit
o f A nouk de Brauwere to have facilita te d th e ir collaboration, crossing not only scientific boundaries,
but also language and in stitu tio n a l ones. A fte r 6 years, we are proud o f the results, but are also well
aware th a t the w ork is fa r from finished. There are clear scientific challenges w aiting fo r us: closer
collaboration w ith geochem ists and environm ental chem ists to develop a m echanistic metal model,
- 13 -
investigate the potential o f m odelling newly em erging p ollutants like nanom aterials and endocrine
disruptors, ecological m odelling. N otw ithstanding the sig n ifica n t e ffo rt put so fa r in the scientific
integration, we w ant to fu rth e r increase it in order to dem onstrate the usefulness o f our developed
tools. Yet, if we really w ant to go to the next level, we should include players and interests beyond
the science platform . The Scheldt Basin being densely populated, better understanding and
predicting the com plex dynamics o f the river system and its response to the diverse p ollution
pressures has a clear im portance fo r society. We see o u r application to the VLIZ North Sea Award as
a firs t a tte m p t to take th is step.
References
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Servais, M. Elskens, W. Baeyens, T. Kärnä,.B. de Brye and E. Deleersnijder. 2009. Design o f a
sam pling strategy to o p tim a lly calibrate a reactive tra n s p o rt m odel: Exploring the potential fo r
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concentrations in natural surface waters: a review. Crit. Rev. Environ. Sei. Technol.,
doi: 1 0 .1 08 0 /10 64 33 8 9.2 01 3.829978.
de Brye B., A. de Brauwere, O. Gourgue, T. Kärnä, J. Lambrechts, R. Com bien and E. Deleersnijder.
2010. A finite-elem ent, m ulti-scale m odel o f the Scheldt trib u ta rie s, River, Estuary and ROFI.
Coastal Engineering 57:850-863, doi: 10.1016 /j.c o a s ta le n g .2 010.04.001.
de Brye B., A. de Brauwere, O. Gourgue, E.J.M. Delhez and E. Deleersnijder. 2012. Water renewal
tim escales in the Scheldt Estuary. Journal o f Marine Systems 94:74-86,
doi: 10.1016 /j.jm a rs y s .2011.10.013.
Delhez E.J.M., B. De Brye, A. de Brauwere and E. Deleersnijder. (in review). Residence tim e vs
influence tim e. Journal o f Marine Systems.
Elskens M., O. Gourgue, W. Baeyens, L. Chou, E. D eleersnijder, M. Leermakers and A. de Brauwere.
(in review). M odelling metal spéciation in the Scheldt Estuary: com bining a fle xib le -re so lu tio n
tra n sp o rt m odel w ith em pirical fu nctio ns. Science o f the Total Environment.
Gourgue O., W. Baeyens, M.S. Chen, A. de Brauwere, B. de Brye, E. Deleersnijder, M. Elskens and V.
Legat, (in press). A depth-averaged tw o-dim ensional sedim ent tra n sp o rt m odel fo r
environm ental studies in the Scheldt Estuary and tid al river network. Journal o f Marine Systems,
doi: 10.1016 /j.jm a rsys. 201 2.05.004.
Matton V. 2012, M odélisation de l'âge des bactéries Escherichia coli dans l'estuaire de l'Escaut,
Master thesis, Université catholique de Louvain, Louvain-la-Neuve, Belgium.
O uattara N.K., A. de Brauwere, G. Billen and P. Servais, (in press). M odelling faecal contam ination in
the Scheldt drainage network. Journal o f Marine Systems, doi: 1 0.1016 /j.jm a rs y s .2012.05.004.
- 14-
ORAL, POSTER & DEMO
PRESENTATIONS
The firs t buoy fo r continuous measuring o f surface Suspended
Particulate Matter concentration on the Belgian inner shelf
Baeye................4,’ Frederic Francken1, Michael Fettweis1, Dries Van den Eynde', Lieven Naudts2
1 Royal Belgian Institute o f Natural Sciences (RBINS), O perational D irectorate Natural Environm ent
(OD Nature), Suspended M atter / Seabed M odelling and M onitoring Group, G u Ilede Ile 100, B-l 200
Brussels, Belgium
Email: Matthias.Baeve@mumm.ac.be
2 Royal Belgian Institute o f Natural Sciences (RBINS), O perational D irectorate Natural Environm ent
(OD Nature), M easurem ent Services Ostend, 3de en 23ste Linieregim entsplein, B-8400 Oostende,
Belgium
SPM concentration is a key param eter to describe the environm ental status, and to evaluate and
understand the im pact o f human activities in nearshore areas. Long-term m easurem ents are needed
in ord er to resolve all variations in SPM concentration. In fall 2013, continuous buoy measurements
o f SPM concentration were initiated and realized in close cooperation w ith VLOOT dab who is the
responsible fo r m aintaining the navigational buoys in the Belgian waters. Both parties agreed upon
to select the AW cardinal buoy fo r holding the OBS-5+ (optical backscatter p oint sensor) at its side.
The stand-alone OBS-5+ is equipped w ith an a n ti-b io fo u lin g w iper and installed in a stainless steel
fram e hanging at about 1.5m under sea surface. Both in s itu and in lab sensor calibrations were
perform ed, to g e th e r w ith burst sam pling over long enough tim e guaranteeing qualitative SPM
concentration data. The AW buoy (51°22.42’ N 3°7.05’E) is located at about 6km o ff Zeebrugge
harbor, in a w ater depth o f 10m and in the direct p ro x im ity o f the benthic trip o d location MOW1
(51°22.04’ N 3°6.95’ E, m easurem ents since 2005). The m otivation fo r having both types o f in situ
m easurem ents co-located is the RBINS-OD Natural Environm ent co m m itm e nt w ith in the European
fram e w o rk JERICO (w w w .ierico-fp7.eu) WP 10.6, viz. inter-com parison study between SPM
concentrations derived from d iffe re n t platform s (i.e. buoys, benthic fram es, satellite). In a second
phase, an upgrade o f the system w ith a second w ater q u a lity sensor (e.g. flu o rim e te r) and a m odule
fo r real-tim e data transm ission is foreseen (currently under m arket study investigation).
Processes affecting SPM concentration are turbulence, tides, neap-spring cycles, m eteorological
events, season, and o the r long-term flu ctua tion s. In th is poster a tim e-series o f about 20 days
(26 September - 16 October, 2013) reveals new insights in the short- (storm s) and m edium -term
(spring-neap cycle) sedim ent dynamics at d iffe re n t depths, such as vertical m ixing and suspended
sedim ent stra tifica tio n . Once (much) more data have been gathered, correlation w ith satellite
im agery (downloadable from the GRIMAS extraction to o l w ebsite) w ill be investigated.
- 16 -
How sensitive is sole larval dispersal in the North Sea to the
param etrization o f larval duration? A m odelling study
Barbut Léo12, Geneviève Lacroix1, Filip A.M. V olckaert2
1 Royal Belgian Institute o f Natural Sciences (RBINS), DO ‘ N ature’
Gulledelle 100, B-1200 Brussels, Belgium
E-mail: L.Barbut@mumm.ac.be
2 Biodiversity and Evolutionary Genomics, Katholieke U niversiteit Leuven (KULeuven)
Ch. D eberiotstraat 32, B-3000 Leuven, Belgium
C onnectivity th ro u g h o u t the life cycle o f fla tfis h remains an open question, especially at the early
life stages. The case o f sole (Solea solea) is o f particular interest because it is one o f the m ost
valuable com m ercial species in the North Sea. It is crucial to understand how the spawning grounds
and nurseries are connected and w hat are the processes influencing larval retention and dispersal in
order to propose appropriate m anagem ent measures. Especially, dispersal durin g the larval stage is
still poorly known. The tra n sp o rt o f sole larvae fro m the spawning grounds to the nurseries is
driven by hydrodynam ic processes but the fin al dispersal pattern and larval abundance at nurseries
m ig ht be affected by biological processes and environm ental factors. Larval T ra n spo rt Models
(LTMs) coupled to Individual-Based Models (IBMs) are more and more com m only used to assess the
relative c o n trib u tio n o f these processes on the larval dispersal. IBMs allow to take into account
grow th to estim ate the duration o f dispersal based on environm ental co nd itio ns m et by the larvae.
These m odels may be sensitive to process param etrization and may give d iffe re n t results fo r
param etrizations derived fro m the same data set. The Larvae & C o m odel (Lacroix e t al., 2 0 1 3 ) used
in the fram e o f B-F ish C onnect p roject couples the 3 D hydrodynam ic m odel C oherens w ith an IBM o f
sole larvae. It is used here to investigate the im pact o f param etrization o f the stage duration on the
dispersal o f sole larvae in the North Sea. In th is study, we compare tw o param etrizations (Rochette
e t al., 2 0 1 2 and Lacroix e t a!., 2 0 1 3 ) o f the stage duration (tem perature dependent) derived fro m
the same data set (m ainly Fonds, 1 9 7 9 ). We show th a t o nly small differences o f the stage duration
param etrization may induce sign ifican t differences o f the dispersal pattern, connectivity and larval
recruitm ent at nursery. This h ig hligh ts the im portance to param etrize biological processes w ith
accuracy and the need to collect su fficie n t data (samples, genotypes and o to lith s) and conduct
experim ental studies to derive biological processes param etrizations in ord er to im prove m odel’s
reliability.
References
Fonds M. 1979. Laboratory observations on the influence o f tem perature and sa lin ity on
developm ent o f the eggs and grow th o f the larvae o f Solea solea (Pisces). Marine Ecological
Progress Series 1:91 -99.
Lacroix G., G.E. Maes, L.J. Bolle and F.A.M. Volckaert. 2013. M odelling dispersal dynamics o f the
early life stages o f a marine fla tfis h (Solea solea L.). Journal o f Sea Research 84:1 3-25.
Rochette S., M. Huret, E. Rivot and O. Le Pape. 2012. C oupling hydrodynam ic and individual-based
models to sim ulate long-term larval supply to coastal nursery areas. Fisheries Oceanography
21:229-242.
- 17 -
Influence o f the storage m ethod on the q u ality o f Norway lobster
(Nephrops norvegicus)
Bekaert Karen, Daphné Deloof, Lisa Devriese, Sara Maes, Kevin Vanhalst, D irk Verhaeghe
and Johan Robbens
Anim al Sciences Unit - A quatic Environm ent and Quality, Institute o f A g ric u ltu ra l and Fisheries
Research (ILVO), A nkerstraat 1, 8400 Oostende, Belgium
E-mail: karen.bekaert@ ilvo.vlaanderen.be
Norway lobster (Nephrops norvegicus), as many o the r seafood products, is a very perishable food
item. Therefore, o ptim al handling and storage practices, at sea and ashore, are essential
com ponents in the q u a lity m anagem ent to realize a m axim um return on national and international
markets. In Ireland, Norway lobster is stored on board in a stacked way: a layer o f ice is placed in a
box, follow ed by Norway lobsters, a bag w ith fine meshes and on to p again a layer o f ice. This
m ethod has the advantage th a t the fine mesh protection m inim izes damage to limbs as it provides
a protective cover when ice is removed during sorting and also helps prevent bleaching. A t ILVO, an
e xperim ent was conducted to te st which influence th is m ethod has on the q u a lity o f Norway lobster
and its u tility fo r Belgian fisherm en was evaluated as an alternative to the tra d itio n a l icing o f
Norway lobster (ice between the Norway lobsters). The difference between the tw o storage m ethods
was assessed by using m icrobiological (Total Viable C ount on Marine Agar and Iron agar, H2Sproducing bacteria, Pseudomonas spp.), sensory (Q uality Index Method) and chemical parameters
(Total Volatile basic N itrogen) during a 14-day storage experim ent.
The firs t 5 days o f the experim ent, there was no difference in sensory, chem ical and m icrobiological
param eters between the storage m ethods. From day 6 o f storage, a sign ifican t higher am ount o f
bacteria was observed on the Norway lobster stored in the Irish way fo r to ta l viable count on Marine
Agar and H2S-producing spoilage bacteria. However, no sig n ifica n t difference could be observed fo r
the o the r m icrobiological param eters or fo r the sensory and chem ical parameters. The am ount o f
Total Volatile Basic Nitrogen started to increase from day 7 o f storage. This coincided w ith the
grow th o f Pseudomonas spp., which are known spoilage bacteria o f Norway lobster (Boziaris e t al.,
2011). The direct contact w ith ice o f the tra d itio n a l Belgian storage m ethod clearly lim its grow th o f
m icroorganism s. On the o the r hand, great variations in results between individuals, probably due to
th e ir position in the boxes, can explain th a t the other param eters did not d iffe r significantly. To
conclude, fo r short fish in g trip s as is the case in Ireland, the use o f the meshed bag fo r storage o f
the Norway lobster cannot be considered as disadvantageous. However, th is storage m ethod is not
applicable to the Belgian situation due to longer sea trips. Therefore, we advise the fisherm en to
continue storing the Norway lobsters in the tra d itio n a l way.
References
Boziaris I.S., A. Kordila, and C. N eofitou. 2011. M icrobial spoilage analysis and its effect on chemical
changes and shelf-life o f Norway lobster (Nephrops norvegicus) stored in air at various
tem peratures. International Journal o f Food Science and T echnology 46(4):887-895.
-18-
Wastewater tre a tm e n t using microalgae
Beuckels A n nelies1, Erik Sm olders2 and Koenraad M uylaert1
1 A quatic Biology, KU Leuven Kulak, Etienne Sabbelaan 53, 8500 K o rtrijk, Belgium
E-mail: annelies.beuckels@ kuleuven-kortriik.be
2 Soil and Water Management, KU Leuven, Kasteelpark Arenberg 20 bus 2459, 3001 Leuven,
Belgium
The discharge o f secondary effluents fro m wastewater treatm ent, containing nitrogen (N) and
phosphorus (P), can cause a risk o f e utrophication o f surface waters and seas. Microalgae have the
a b ility to remove these nutrients sim ultaneously from wastewater. Besides P is becoming scarce and
N more expensive to produce, which stim ulates the reuse o f both nutrients fro m wastewater. Due to
the depletion o f m ineral phosphate reserves, the recycling o f P w ill be necessary to guarantee the
production o f fe rtiliz e r fo r food production. The produced algal biomass contains valuable lipids,
carbohydrates and proteins th a t can be used as source o f energy, b ulk chem icals and animal feed.
The use o f wastewater n utrients is necessary to make algal biofuel production both sustainable and
econom ically achievable. The objective o f th is research is to id e n tify the bio tic and abiotic
co nditions th a t are o ptim al fo r the removal o f P from wastewaters by m icroalgae.
Wastewaters have a variable N:P ratio therefore we exam ined the effect o f the initia l N:P ratio on
algal grow th, n u trie n t removal and biomass com position. Batch n utrien t uptake experim ents were
perform ed w ith the alga C hlorella vulgaris in synthetic wastewater. This m edium contained various
N (10 to 5 0 m g L ') and P (2 to 10 m g L 1) concentrations. The microalgae com pletely removed 10 to
3 0m gL ' N and 2 to 4 m g L ' P from the m edium . In these treatm ents, the fin al biomass concentration
was up to a fa cto r 2 lower. The biomass m olar N:P ratio ranged fro m 1 5 to 42 indicating th a t more
N is accum ulated, compared to the Redfield ratio o f 16. Therefore com parative batch experim ents
w ith the alga Scenedesmus obliquus, where more P accum ulation is expected, are perform ed.
Real w astew ater also contains P com pounds d iffe re n t from orthophosphate. These inorganic (e.g.
sodium triphosphate, struvite) and organic (e.g. phosphate esters) P com pounds are often not
readily available. Therefore the bio ava ila b ility o f m odel P com pounds is being tested.
-19-
Ecological niche predicts ph o to p ro te c tio n capacity o f
m icro p h yto b e n th ic diatom s in ha biting intertidal m udflats
Blomm aert Lander1, Alexandre Barnett2, Vona Meleder3, Pierre Gaudin3, Wim Vyverm an1, C hristine
Dupuy2, Johann Lavaud2 and Koen Sabbe'
1 P rotistology & A quatic Ecology Laboratory, Dept Biology, Ghent University, Belgium
E-mail: Lander.Blommaert@UGent.be
2 UMR7266 LIENSs, In s titu t du Littoral et de l’Environnem ent, CNRS/Université de La Rochelle,
France
3 UPRES EA 2160 ‘ Mer, Molécules, Santé’, Université de Nantes, France
Despite being exposed to a highly flu ctu a tin g lig h t clim ate, inte rtid a l sedim ents belong to the m ost
productive ecosystems on Earth. The main prim ary producers in th is habitat are diatom s. They
belong to tw o main fu n ctio n a l groups: large m otile diatom s (epipelon), which move free ly in
between sedim ent particles, and sm aller diatom s which live in close association w ith individual sand
grains (epipsamm on). W ithin the epipsam m on d iffe re n t grow th fo rm s can be distinguished. Nonm otile fo rm s live appressed to or stalked on sand grains. O ther epipsam m ic species however are
m otile but o nly move w ith in the sphere o f individual sand grains. One o f the main physiological
mechanisms o f photop rote ction in diatom s is Non Photochemical Quenching (NPQ) which is
associated w ith the xa nth op h yll cycle. In stressful lig h t co nd itio ns the xa nth op h yll pigm ent
diadin oxa nthin is converted into d ia to xan th in which safely dissipates excess energy as heat. It has
been hypothesized th a t epipelic diatom s can m igrate w ithin a vertical lig h t g radient to the most
optim al lig h t clim ate whereas epipsam m ic fo rm s m ust be able to cope w ith a flu c tu a tin g ligh t
clim ate using m ainly physiological mechanisms. NPQ w ould therefore be more p erform an t in
epipsam m on than epipelon. We tested the a b ility o f a selection o f representatives o f each grow th
fo rm to perform NPQ durin g 5min high lig h t exposure (fu ll sunlight, 200 0p m o l photons m 2 s ') and
measured NPQ. We observed th a t epipelic diatom s have a lower NPQ potential than epipsam m ic
ones. Interestingly, small m otile epipsam m ic grow th form s, despite being phylogenetically more
closely related to epipelic taxa than to o the r epipsam m ic form s, have an interm ediate NPQ
photop rote ction capacity. This observation underscores the im portance o f grow th fo rm and not
phylogenetic relatedness as the prime dete rm ina nt shaping the physiological photoprotective
capacity o f benthic diatom s.
- 20 -
A lifetim e inspired by the ocean: marine environm ental effects on
human physiology
Bourgois Jan
Faculty o f Medicine and Health Sciences, D epartm ent o f M ovement and Sport Sciences, Ghent
University, Ghent, Belgium
E-mail: ian.bourqois@ uqent.be
The sea showed th a t it can be a deadly enemy and th a t those who go to sea m ust do so in the
knowledge th a t they may encounter dangers o f the highest ord er (Jacobs & Hawley, 2011). My
fam ily, up to my fa th e r’s generation, were fisherm en. My g ra nd fa the r had great stories about
fearlessly sailing to Iceland to fish fo r cod and how he survived the sinking and abandonm ent o f a
fish in g boat. It helped explain w hy my g ra nd m o th er d id n ’t w ant her sons and grandsons to become
sailors. I became an exercise p hysiologist (exercise physiology can be defined as the study o f how
the human body, fro m a fu n ctio n a l standpoint, responds, adjusts and adapts to physical a ctivity and
exercise), teaching and doing fundam ental research in a sport and clinical setting. However, my life
was inspired by the ocean. In my
teenage years - during holidays - I sailed dinghies, w orked as
beach lifeguard in Ostend (Belgium) and as deck mate on a container ship crossing the North
A tla n tic Ocean. In 1980, I crossed the North A tla n tic Ocean again in a 44 fo o t yacht. One year later,
I left my hom etown to sail the W hitbread Round the W orld Race 1981-1982. A t the start o f my
professional career in 1983, I became a m em ber o f the national rowing squad. In th is context, it
seems logical th a t part o f my research is conducted on w ater-related sports activities (rowing,
sailing and kite surfing). A few years ago, I invited Prof. Mike T ipto n from the U niversity o f
Portsm outh (UK), a w orld a u th o rity on survival at sea and th erm oreg ula tion in cold and hot
environm ents (Golden & T ipton, 2002), to give some lectures on beach lifeguarding and cold w ater
im m ersion to my students. A t th a t m om ent, I realized th a t marine environm ental effects on human
physiology are w orth studying and th a t the expertise o f our research group is suitable to do
research in th is field.
The greatest wilderness on earth is the ocean and w orking in th is w ilderness as a marine scientist
seems w onderful to many people. Marine science workers bring a specific skill to a problem .
Sometimes, th a t problem lies in a com fortable neutral environm ent. But more likely, the problem
w ill yield o nly to prolonged study in an uncom fortable and harsh environm ent. (Garrison, 2010).
Water is one o f the m ost hostile and life-threatening natural environm ents fo r inadequately
prepared individuals. Health maintenance at sea is crucial fo r marine science w orkers to do th e ir jo b
very th orou g hly, and to survive the possible threats o f an ocean environm ent. Therefore, a basic
understanding o f how the human body w orks in a specific marine environm ent (therm oregulation in
heat, cold and w et environm ents, adaptive response to real and apparent m otion, s h ift w ork,...),
knowledge o f specific health issues at sea (dehydration, hypotherm ia, seasickness, sleep
deprivation,..) and possible counterm easures are necessary to m aintain o ptim al physical and mental
perform ance as well as survival.
References
Garrison T. 2010. Oceanography. An invitation to marine sciences. 7th Ed. Brooks/Cole, Cengage
Learning.
Golden F. and M. T ipto n. 2002. Essentials o f sea survival. Human Kinetics.
Jacobs M.E. and C. Hawley. 2011. Safety and survival at sea. In: Auerbach P.S. 2011. W ilderness
Medicine, 6th Ed. Chapter 83:1666-1692. Elsevier.
- 21 -
Prevalence o f the parasites Sacculina c a rc in i on Liocarcinus holsatus
and P eltogaster p a g u ri on P agurus b e rn h a rd u s in the Belgian part o f
the North Sea
Breine Naomi T., Sofie Vandendriessche and Kris Hostens
Institute fo r A g ricu ltu ra l and Fisheries Research (ILVO), A quatic Environm ent and Quality, Bioenvironm ental Research, A nkerstraat 1, 8400 Oostende, Belgium
E-mail: naom i.breine@ ilvo.vlaanderen.be
Sacculina c a rc in i and Peltogaster p a g u ri are rhizocephalan parasites on com m on sw im m ing crab
Liocarcinus holsatus and com m on herm it crab Pagurus bernhardus, respectively. The order
Rhizocephala consists o f parasitic barnacles w ith an extrem ely reduced m orphology. Hosts are
attacked by female cyprid larvae, which fo rm an internal root-system (the interna), th a t eventually
can evaginate an external reproductive body (the externa) on which male cyprid larvae may settle.
A fte r male settlem ent, the externa m atures and several batches o f parasitic nauplii larvae are
released. The externa occupies the same place as em bryos in ovigerous females, and thus m im ic a
brood o f eggs, fo r which both male and female hosts w ill tend to as if it was th e ir own. The effects
o f infection on the host include cessation o f m oulting, m odifications o f the secondary sexual
characteristics and in fe rtility.
Seven years o f epibenthos traw ling data fro m various stations in the Belgian part o f the North Sea
(BPNS) were used to evaluate the prevalence o f both parasites on th e ir respective hosts. Differences
in infection rates were exam ined between years (2006 to 2012), seasons (spring vs. autumn),
distance from the shore, and three human pressures (im pact vs. reference sites fo r sand extraction,
dredge disposal and offshore w ind energy developm ent). For Sacculina c a rc in i also gender and size
preference were analyzed.
Over the seven years sam pling period, a to ta l o f 20,158 L. holsatus and 4 3,114 P. bernhardus
individuals were exam ined fo r the presence o f externae. Sacculina c a rc in i externae were fo un d on
676 crab individuals (or 3.35% o f the flying crab population). Peltogaster p a g u ri externae were
found on 161 herm it crab individuals (i.e. 0.37% o f the herm it crab population in the BPNS). A
higher percentage m ig ht have been infected w ith internae, but th is was not exam ined as only quick
visual screenings o f parasites were made. For both host species there was a sign ifican t difference in
infection percentage between the consecutive years and between the seasons, w ith higher infection
rates in 2006-2007, and in spring. Sacculina c a rc in i showed no preference fo r specific crab sizes,
but a sign ifican t preference fo r female crabs was found. No sign ifican t difference was observed
between near-shore, m id-shore and off-shore samples. Also, no sig n ifica n t differences were noted in
infection percentages between im pact and reference samples fo r the three human pressures.
In summary, we found substantial variation in infection rates, which seemed m ostly determ ined by
natural interannual and seasonal differences, and by host-specific preferences o f the parasites. We
found no evidence th a t human activities have an influence on the infection rates.
- 22 -
Where did com m on porpoise (Phocoena phocoena) come from before
stranding?
Brihaye Esther',T hib au t Bouveroux2, Steven Degraer3, Valérie D ulière3, Jan Haelters3, Sylvain Pezeril2
and T h ie rry ja u n ia u x '
1 D epartm ent o f Pathology, V eterinary College, U niversity o f Liège, Sart Tilm an Bat B43,
B-4000 Liège, Belgium
E-mail: ebrihaye@ student.ulg.ac.be
2 Observatoire pour la Conservation et l’Etude des A nim aux et M ilieux Marins (OCEAMM),
F-59123 Zyudcoote, France
3 Royal Belgian Institute o f Natural Sciences (RBINS), Gulledelle 100, B-l 200 Brussels, Belgium
Since the end o f the 1990’s, a strong increase in the stranding o f the com m on porpoise (Phocoena
phocoena) has been observed in the southern North Sea. As strandings cu rren tly yield m ost o f
inform a tion about the com position o f the populations o f marine mammals, our study aims to
characterize the main characteristics w ithin the stranded population, and to refine the
representativeness o f the strandings as an ecological ind icato r o f the populations at sea. Therefore,
the inform a tion collected during the necropsies o f 893 animals stranded between 1990 and the end
o f June 2013 on the Belgian and northern French coast was used. Furtherm ore, a firs t a tte m p t to
m odel the backtracking d rift o f carcasses was used to estim ate the origin o f the death o f animals.
The sim ulations were realized over tw o m ajor stranding peaks (from March 1st till May 31st 2006
and from March 20th till May 20th 2013) by means o f the OSERIT 1.0 softw are (Oil Spill valuation
and Response Integrated Tool). One o f the main causes o f death is by-catch (accidental capture in
fish in g nets), which m ostly concerns the juveniles, due to the more coastal d is trib u tio n o f this
specific age group. A d ditio na lly, m ost o f by-caught animals died in the western w ater o f our study
area and d rift some days before stranding. By-catch represents more than h alf the causes o f death
during the main peak o f stranding. This peak occurs in spring and can be p artially explained by the
strong concentration o f recreational fish in g during th is period in the Western part o f the studied
area. The m odel sim ulations suggested th a t a large part o f the found animals come fro m waters
lining the Dutch, Belgian and northern French coast. Moreover, th e ir likely areas o f origin are very
wide, covering the English Channel and the southern North Sea. This phenom enon could be partially
explained by the current patterns, the tides and the w ind, w hich w ould be the reason behind the
high density o f strandings on these coasts. Finally, the progressive increase o f the strandings since
1990 is confirm ed by our results w ith on average only 6.3 animals per year between 1990 and
2000, and 80.5 animals per year between 2001 and 2012. It w ould be explained in particular by the
s h ift o f the population o f porpoises in the northern North Sea to the southern North Sea and by the
higher incidence o f by-catch since the beginning o f the 2 0 0 0 ’s.
- 23 -
The RV Simon Stevin: home o f the newest oceanographic tools fo r
scientists
C attrijsse Andre, Thanos G kritzalis, Karen Rappé, M ichiei T ’Jampens and Wim Versteeg
Flanders Marine Institute (VLIZ), InnovOcean site, Wandelaarkaai 7, 8400 Oostende, Belgium
E-mail: andre.cattriisse@ vliz.be
The research vessel Simon Stevin, operating m ainly in the Belgian part o f the North Sea, has been
servicing marine scientists fo r alm ost tw o years. W ith a high resolution m ultibeam , a current
profiler, a dynam ic position ing system, tw o laboratories, a large aft A-fram e and a data-acquisition
system the ship is well designed to support marine science. Moreover the low underw ater noise
generated by the vessel allows acquisition o f high q u a lity acoustic data.
Since its com m issioning the RV Simon Stevin has been fu rth e r equipped w ith high tech instrum ents
and sam pling e quipm ent to provide technological su pp ort fo r various marine research disciplines:
■ A flow-cytom eter collects images and a set o f physical m easurem ents o f each particle in a water
sample allow ing species ide ntifica tion o f m icroplankton;
■ The Video Plankton Recorder (VPR) allows autom ated detection o f plankton th ro ug h the
collection o f in-situ images and real tim e image analysis while being towed;
■ The ZooSCAN, a lab image analysis to ol, identifies in an autom ated way Zooplankton;
■ The Sediment Profile Imaging (SPI) camera provides in situ im aging o f organism -sedim ent
relationships on the seafloor obtained by a vertical cross section o f the se dim e n t/w ater interface;
■ A video-cam era frame inspects and surveys underw ater features in real-tim e;
■ A dedicated winch operates the VPR, the SPI and the camera fram e;
■ The ROV Genesis gathers seabed samples to g e th e r w ith videos and images o f the seafloor and
underw ater structures.
The underway data acquisition system collects continuously data on
tem perature and chlorophyll-a fluorescence and has been upgraded w ith:
sea surface
salinity,
■ A Fast Repetition Rate Fluorometer (FRRf) to acquire data th a t are used to estim ate prim ary
p roductivity;
■ A nutrient analyser to measure concentrations o f Nitrate, Phosphate and Silicate;
■ A pH sensor (ISFET type)
■ An Oxygen sensor (optode)
■ pCOz analysers to determ ine C02 concentrations in air and in water;
■ A Submersible Ultraviolet Nutrient Analyser (SUNA) to measure Nitrate.
- 24-
Tube fo o t mechanical properties in the sea urchin
P a ra cen trotus livid u s from habitats presenting a range o f seawater
velocities
Cohen-Rengifo M ishal12, Patrick Flam m ang1 and Philippe D ubois2
1 Laboratoire de Biologie des Organism es m arins et Biom im étism e, In s titu t des Biosciences,
Université de Mons, 23 Place du Parc, 7000 Mons, Belgium
E-mail: m ishal.cohen.r@ qm ail.com
2 Laboratoire de Biologie Marine, Université Libre de Bruxelles, CP160/15
50 Av. F.D. Roosevelt, 1050, Brussels, Belgium
Intertidal rocky shores are considered as extrem ely stressful environm ents wherein benthic marine
invertebrates are subjected to strong hydrodynam ic forces due to wave action and likely to detach
them from the substrate. Hydrodynam ics is therefore one o f the m ost im p o rta n t factors
determ ining the survival and d istrib u tio n o f species as well as shaping benthic com m unities. To
counteract these forces, many marine organism s have developed specialized structures, including
adhesive organs. For instance, echinoids e x h ib it appendages known as tube feet or podia. Tube feet
consist o f a distal fla t deform able disc th a t adheres to the substrate and th a t is connected to the
skeleton th ro u g h a cylindrical shaft called the stem. The aim o f th is study was to evaluate tu be fo o t
adhesive and mechanical properties in the sea urchin Paracentrotus lividus from three
subpopulations exposed to d iffe re n t seawater velocities. In May 2013, a du lt sea urchins were
collected fro m tide pools at 3 localities around the Crozon peninsula in Britany (France). These
localities, llien, M orgat and Cap de la Chèvre, d iffe r according to th e ir hydrodynam ic conditions,
w ith mean w ater velocities o f 9.1 ± 4 . 8cm.s ', 16.4 ± 5 .3 cm .s' and 44.9 ± 13.5 cm .s', respectively.
Specimens were b ro ug ht alive to the laboratory where m orphom etric as well as tenacity
m easurem ents were taken. A safety fa c to r predicting the flo w ve lo city at which sea urchins are
prone to detach from the substrate was then calculated. In a dd ition, tra ctio n tests were perform ed
on tube feet in ord er to determ ine th e ir m echanical properties, i.e. e xten sibility, strength, stiffness
and toughness. Sea urchin size decreased w ith increasing w ater velocity and th is trend was
sta tistically significant. A ttachm ent force and both whole individual and single tube fo o t tenacity
increased w ith increasing flo w velocity. A ll mechanical properties were also higher in the
subpopulation where the highest flo w velocity was recorded, but these differences were statistically
sign ifican t o nly fo r e xte n s ib ility and toughness. Safety fa cto r analysis indicated that, if subjected to
increasing hydrodynam ic forces, sea urchins fro m Cap de la Chèvre w ould be the last to detach
compared to individuals from the o the r tw o subpopulations. Thus the tube feet o f Paracentrotus
lividus show an intraspecific plasticity, th e ir mechanical properties varying according to local
seawater velocities which lead to a better attachm ent capacity in the m ost exposed habitat.
- 25 -
Microplastics caught in herring gili rakers: illustra tion by scanning
electron m icroscopy
Collard France1, Krishna Das2 and Eric Parm entier1
1 Functional and Evolutionary M orphology Laboratory
University o f Liège, Allée de la Chimie 3, 4000 Liège, Belgium
E-mail: fcollard@ doct. ulq.ac.be
2 Laboratory o f Oceanology
University o f Liège, Allée de la Chimie 1 7, 4000 Liège, Belgium
Plastics are persistent and have accum ulated in the oceans fo r several decades. Plastics may adverse
w ild life in many ways: they can be ingested by marine vertebrates and cause internal w ounds in the
digestive tract. Plastics are also vectors o f organic p ollutants including PCBs and DDT. Once
ingested, plastics may release these pollutants in the organism . Plastics present in the marine
environm ent frag m en t in small pieces by mechanical stress and UV radiation leading to the socalled m icroplastics sm aller than 5mm. Little is known about m icroplastics ingestion and to x ic ity in
planktivorous fish such as the herring, Clupea harengus. Planktivorous fish have g ili rakers, which
may fu nctio n as particle tra p fo r m icroplastics. This study aims to describe and characterise
m icroplastics present on gills o f the herring, Clupea harengus. Fifteen g ili cavities were sampled in
January 2013 in the Channel and the North Sea during the IBTS fish ery campaign (organized by the
IFREMER). Gills were placed in a form aldehyde/seaw ater solution u ntil preparation fo r scanning
electron m icroscopy (SEM). SEM was used in order to detect m icroplastics which are too small to be
observed by a dissection m icroscope, to compare them w ith the distance between g ili rakers and to
characterise the surface and the shape o f m icroplastics.
Scanning electron m icroscopy revealed large variety o f m icroplastics, which lengths ranged fro m
0.05 to 5mm. Relationship between m icroplastics length and distance between gili rakers was
analysed on the same branchial arch. The present study revealed the presence o f m icroplastics in an
edible species o f high econom ic value and raise question a bo ut potential im pact on the herring and
its consumers, including human beings.
- 26 -
Using cold-w ater coral m ini-m ounds as analogue fo r giant m ound
grow th: assessment o f environm ental drivers and anthropogenic
impact
C o lla rtT im 1, Kerry Howeii2, Heather Stewart3, Jean-François Bou rille t4, Estefanía Llave5, D om inique
Blamart6 and David Van Rooij1
1 Renard Centre o f Marine Geology (RCMG), Ghent University, Belgium
Tim.Collart@ UGent.be
2 Marine Institute, Plymouth University, UK
3 British Geological Survey (BGS), UK
4 Institute Français de Recherche pour l’E xploitation de la Mer (IFREMER), France
5 Institute o f Geology & Mineral Exploration (IGME), Spain
6 Laboratoire des Sciences du C lim at et de L’Environnem ent (LSCE), Gif-sur-Yvette, France
C old-water corals (CWC) are found along the whole north-eastern A tla n tic Margin fro m Norway to
the G ulf o f Cadiz. In the Porcupine Seabight, these coral reefs (m ainly Lophelia pertusa and
M adrepora oculata) accum ulate into large m ounds o f up to 250m high (e.g. Challenger Mound),
which have been well studied over the past tw o decades (Roberts et al., 2006). The detailed
m echanism o f the start-up phase o f such large CWC m ounds is however not yet fu lly understood.
Therefore, it is essential to study analogues o f these stages th a t are not well recorded in larger
mounds. The FWO MINIMOUND project (2013-2016) aims to investigate the initia tio n , grow th and
demise o f ‘sm all’ CWC m ounds and to determ ine the role o f clim atic and hydrocarbon-seepage
related processes as well as anthropogenic impact. This h igh-resolution m u ltid iscip lin a ry study w ill
focus on three ‘ m in im o u n d ’ provinces along the Biscay continental m argin: (1) the Explorer and
Dangeard Canyons on the Celtic Margin (Stewart et al., 2013), (2) the Guilvinec Canyon on the
Arm orican Margin (De Mol e t al., 2011) and (3) the Upper Ferroi Canyon on the Cantabrian Margin.
These m inim ounds are fossil (9.7ka BP) and occur at relative shallow depth on the interface between
the Eastern North A tla n tic Central Water (ENACW) and the M editerranean O utflow Water (MOW).
C ontrastingly, m ost present-day living CWC reef habitats dwell in the deeper MOW depth range,
relying on the density and dynamics o f th is w ater mass fo r th e ir food supply.
The objectives o f the project are th re efold : (1) the establishm ent o f a ch ro no stratig ra ph ic
fram e w o rk and the reconstruction o f palaeoceanographic changes over the last 15.000 years in
order to determ ine the im pact o f glacial to interglacial clim ate change on the ENACW-MOW interface
and the CWC habitats (Frank e t al., 2011); (2) the m inim ound province at the Upper Ferroi Canyon
shows a close association w ith hydrocarbon-seepage (pockm arks) which allows to assess the role o f
hydrocarbon related processes in CWC mound fo rm a tio n ; (3) the potential im pact o f anthropogenic
fisheries activities w ill be investigated.
These objectives w ill be tackled th ro u g h a coupled geophysical, sedim entological and integrative
approach, including the palaeoceanographic and biogeochem ical study o f USBL guided cores in
cooperation w ith the BGS (UK), LSCE (Gif-sur-Yvette, France), IFREMER (France), IGME (Spain) and IEO
(Spain). Two sam pling cam paigns w ith the R/V Belgica w ill be undertaken. In addition to core
collection, drop fram e images w ill be acquired to allow habitat m apping and predictive m odeling o f
the CWC habitats in cooperation w ith the Marine Institute o f Plymouth U niversity (UK).
References
De Mol L., D. Van Rooij, H. Pirlet, J. Greinert, N. Frank, F. Quemmerais, J.-P. Henriet. 2011. Coldw ater coral habitats in the Penmarc'h and Guilvinec Canyons (Bay o f Biscay): Deep-water versus
shallow -water settings. Marine Geology 282(1 -2):40-52.
Frank N., A. Freiwald, M. Lopez Correa, C. W ienberg, M. Eisele, D. Hebbeln, D. Van Rooij, J.-P.
Henriet, C. Colin, T. van Weering, H. de Haas, P. Buhl-Mortensen, J.M. Roberts, C. De Mol, E.
D ouville, D. Blamart, C. Hatte. 2011. Northeastern A tla n tic cold-w ater coral reefs and climate.
Geology 39 (8):743-746.
Roberts J.M., A.J. Wheeler, A. Freiwald. 2006. Reefs o f the deep: the biology and geology o f coldw ater coral ecosystems. Science 31 2(5773):543-547.
Stewart H.A., J.S. Davies, J. Guinan, K.L. Howell. 201 3. The Dangeard and Explorer canyons, South
Western Approaches UK: Geology, sedim entology and newly discovered cold-w ater coral m in i­
mounds. Deep Sea Research Part II: Topical Studies in O ceanography (0).
- 27 -
Ecological study o f foreshore no urishm ent at the Flemish coast
Colson Liesbet', Gert Van Hoey2, Jan Vanaverbeke1 and Magda V in cx1
1 Marine Biology Research group, Ghent University, Krijgslaan 2 81 -S8, 9000 Gent, Belgium
E-mail: Liesbet.colson@ uqent.be
2 In stitu u t vom or Landbouw- en Visserij Onderzoek (ILVO), Eenheid Dier, A nkerstraat 1, 8400
Oostende, Belgiu
In the fram e w o rk o f ‘ Masterplan K ustveiligheid’ o f the Flemish governm ent, weak spots at the
Flemish coast w ill be managed to increase our coastal safety. One o f the solutions is beach
nourishm ent, w hereby sand is dropped on the beaches to compensate beach erosion fo r a period o f
5 years. To o ptim ize the maintenance o f these nourishm ents (techniques, longevity, costs and
managem ent) in the future, alternatives w ill be investigated. One option is foreshore nourishm ent
on which a p ilo t study was set up at Raversijde-Mariakerke (Belgium).
Foreshore nourishm ent w ill influence the state o f the marine ecosystem in one or another way.
Therefore, a m on itoring program m e was initiated (4SHORE) in autum n 2013 to fo llo w up the
ecological effects o f th is anthropogenic d isru p tio n on the fauna, applying a BACI (Before A fte r
C ontrol Impact) strategy.
The goal o f the ecological m on itoring campaign is to evaluate firs t the ecological value o f the
nourished area before nourishm ent, both in spring as in autum n. Possible changes in the ecological
value due to th is nourishm ent w ill be measured in the fo llo w in g tw o years (spring and autum n). An
im pact (nourished zone) and a control area (same habitat type, not influenced by the impact) are
included in the study.
To determ ine the ecological value or changes in it, we w ill evaluate the present fauna
(m acrobenthos, hyperbenthos, epibenthos and dem ersal fish) and th e ir ecosystem fu n c tio n in g (e.g.
the relationship between the food source and th e ir prey). For delivering an objective ju d g m e n t on
the nourishm ent effects (is it bad or good), we w ill apply standard indicators defined under the
Marine Strategy Fram ework Directive. Changes in the ecosystem w ill be studied via biotic (biomass,
density, diversity) and abiotic (grain size, organic m atter) variables.
- 28-
Using stable isotopes o f m ercury and m eth ylm ercu ry to discrim inate
contam ination profiles between sea bass, D ice n tra rch u s
labrax, populations
Cransveld A lice', David A m o u ro u x2, Emmanuil K outrakis3, Sylvain Bé rai I2, Caiyan Feng2, Julien Barre2,
Joseph Schnitzler' and Krishna Das'
' Oceanology, Sciences Faculty, U niversity o f Liège (B6c), B-4000 S a rtT ilm an , Belgium
E-mail: Alice.cransveld@ ulq.ac.be
2 Fisheries Research Institute, Hellenic A g ricu ltu ra l O rganisation, G-640 07 Nea Peramos, Kavala,
Greece
3 LCABIE-IPREM, UMR 5254 CNRS, Université de Pau et des Pays de l’Adour, F-64053 Pau Cedex 09,
France
Despite many e ffo rts consented in the last decades, M ercury (Hg) em issions have kept rising
w orldw ide. C urrently, anthropogenic inputs dom inate Hg em issions to the atm osphere by far,
natural releases accounting o nly fo r a 4th o f the total. Because Hg has a stable gaseous fo rm (Hg°)
w ith a long residence tim e in the atm osphere (~ 1year), both natural and in d u stria lly produced Hg
can be transported fa r fro m p o in t sources. Therefore, many uncertainties remain in our knowledge
about Hg biogeochem istry.
Our study aims at identifying the d iffe re n t Hg fo rm s found in marine predators in order to
discrim inate d iffe re n t polluted areas and potential p ollutio n sources. More specifically, we seek to
discrim inate contam inations o f local o rigins versus contam ination o f global origins. To achieve this,
we are cu rren tly studying d iffe re n t sea bass, D icentrarchus labrax, populations fro m the A tla n tic
Ocean and Mediterranean. In muscle, liver, kidney and brain tissues, we analyze to ta l M ercury (THg)
and m ethylm ercury (MeHg). We are also te sting the discrim ination power o f Hg's stable isotopes
('"H g , 2°'Hg and 202Hg). Indeed, recent fin d in g s show th a t Hg isotopes can e x h ib it both massdependent (MDF) and m ass-independent fractio na tio n (MIF). This means th a t Hg isotopes provide
tw o d iffe re n t types o f inform a tion at once, both on biological cycling o f Hg, including
bioaccum ulation (MDF), and on chem ical pathways such as photochem ical tran sfo rm atio n s (MIF).
Eventually, we are planning to extend our results w ith com pound specific isotope analysis (CSIA) on
the carbon o f m ethylm ercury.
Prelim inary analysis perform ed on 14 juve nile specimens from the North Sea and the Aegean Sea
indicate th a t THg concentrations are higher in individuals from the North Sea than fro m Greece. The
lack o f correlation w ith size and w eight indicates th a t it is likely linked to a difference in
contam ination levels between the tw o areas. MeHg is the predom inant fo rm o f Hg in muscle, while
the same cannot be asserted fo r liver. Mass dependent isotopic values (6202Hg), were always higher
in muscle than in liver and, fo r each tissue, values were sim ilar between the tw o areas. This is
probably related to the species d is trib u tio n and to some internal Hg m etabolism . For mass
independent isotopic signature (MIF), sea bass fro m the Aegean Sea had a system atically higher
A201Hg value than individuals from the North Sea. Thus, mass independent values seem d e fin ite ly
site dependent and m ig ht be in agreem ent w ith differences in both m ercury sources and cycling in
the North and Aegean Seas. These prelim inary results consequently indicate th a t Hg isotopes may
help to discrim inate fish from d iffe re n t areas. This prom ising outcom e m ust be fu rth e r confirm ed
by extending our sam pling and w ill be coupled to o the r results obtained th ro u g h CSIA.
- 29-
O vertopping induced by oblique waves at Station quay - Oostende
Dan Sebastian1, Corrado A lto m a re '3, Daphné T ho on 2, T om o hiro Suzuki', Tim Spiesschaert'
and Toon Verwaest'
' Flanders Hydraulics Research, Berchemlei 115, B-2140 Antw erp, Belgium
E-mail: sebastian.dan@mow.vlaanderen.be:
2 Coastal Division, Agency fo r M aritim e and Coastal Services, Vrijhavenstraat 3, 8400 Oostende,
Belgium
3 Dept o f Civil Engineering, Ghent University, T echnologiepark 904, B-9052 Zwijnaarde, Belgium
The harbor o f Oostende extended recently and the length and the o rientation o f the groins
protecting the harbor entrance changed. The new co nfig u ra tio n exposes the harbor quay in fro n t o f
the train station to certain wave directions, at large angle respect to the quay normal. Therefore it
became necessary to estim ate the vu ln e ra b ility o f th is quay fo r extrem e storm such as the 1000
year return storm (Hs=4.75m, Tp=12s, w ater level +8.0m TAW). It was calculated (Gruwez et al.,
2011) th a t fo r th is storm the waves approach the Oostende Station quay at an angle o f
a pp ro xim a tely 80°, the H = 1 .5m and T = 1 2s. Storm return walls are planned to be b u ilt on th is quay
and th e ir position and height have to be p ro po rtio na l w ith the estim ated overtopping.
For classical co nfig uratio ns the EurOtop manual (2007) proposes validated form ulas to calculate the
overtopping discharge. In the case o f perpendicular wave attack on a storm return wall the
overtopping is m axim um , but fo r larger wave angles a reduction fa cto r is applied to reflect the
decrease in overtopping discharge. This fa c to r decreases gradually fo r wave angles between 0° and
45° and it keeps a constant value fo r wave angles larger than 45°. It is very probable th a t the
overtopping discharge w ill keep the decreasing trend fo r larger wave angles. To q u a n tify the
reduction o f the overtopping fo r very oblique waves a 3D physical expe rim en t was designed in the
wave ta nk o f Flanders Hydraulics Research, A ntw erp. The scale o f the expe rim en t was decided to be
1:50 and the structure replicating a harbor quay has 8m length, 0.2m height and lm w idth, in
model scale. On to p o f the structure a storm return wall (0 .0 2 /0 .04m ) is placed at d iffe re n t
positions w ith respect to the fro n t edge o f the quay. On the back o f the structure 16 boxes were
placed to collect the overtopping volumes. The w ater level is ranging between -0.015 and +0.020m
w ith respect to the quay level, w hile the waves have H =0.0 3-0.06m and T = 1 .1 -1 .7s. The wave angle
used fo r sim ulations is 80° w ith respect to the norm al. The wave characteristics are measured using
many wave gauges placed in arrays in such way to both separate incident and reflected waves and
characterize the to ta l wave height pattern at the toe o f the structure. Because the wave paddle has
no active absorption system passive absorption m attresses were placed around the basin to
m inim ize the wave reflection.
A fte r fin ish in g o f the planned tests, a clear decrease in the measured overtopping volum es w ith
respect to those calculated was observed. A high va ria b ility o f the overtopping volum es along the
structure was also observed. Detailed wave clim ate analysis was perform ed and the variation o f the
wave height along the structure is correlated w ith the overtopping. The main results o f the
e xperim ent are new overtopping reduction factors fo r very oblique waves at the vertical quays as
well as fo r d iffe re n t heights and positions o f the storm return wall.
References
EurOtop O vertopping Manual. 2007. Wave O vertopping o f Sea Defences and Related Structures:
Assessm ent Manual (Die Kuste version).
Gruwez V., A. Bolle., W. Hassan, T. Verwaest and F. M ostaert. 2011. Numerieke m odellering van het
extreem g o lfklim a a t in de Belgische havens. Deel 1: Haven van Oostende. Versie 2_0. WL
Rapporten, 769_03. W aterbouw kundig Laboratorium & IMDC (l/RA/1 1 273/1 1.1 13/VGR).
- 30 -
Adaptive responses to high environm ental am m o nia in European sea
bass acclimated to d iffe re n t salinities
Dasan A n to ny Franklin, Rindra Rasoloniriana, A m it Kumar Sinha, Ronny Blust and Gudrun De Boeck
Laboratory fo r Ecophysiology, Biochem istry and Toxicology, U niversity o f Antw erp,
Groenenborgerlaan 171, 2020 A ntw erp, Belgium
E-m ail: a d a sa n @ vu b .a c.b e
The European sea bass (D icentrarchus labrax) is increasingly the m ost im p o rta n t marine species in
European aquaculture, ow ing to increased fa rm ing o f the marine fish, especially in the
M editerranean region. European sea bass belong to the euryhaline species o f fish, which im plies
th a t they are capable o f living in environm ents o f wide range salinity. Farmers in the Mediterranean
region are rearing the fish in sea cages and land-based systems, which greatly augm ent am m onia
buildup. This e xperim ental study w ill seek to establish the a da pta b ility o f the fish to High
Environm ental A m m onia (HEA), at d iffe re n t am bient salinities.
The researchers w ill expose European sea bass acclim ated to HEA (20m g.l '), and feed at up to 2% o f
body w eight, to d iffe re n t salinities (32 °/oo, 2 0 °/oo, 10 °/00 and 2 .5 °/oo) in d iffe re n t e xperim ental tanks.
The adaptations o f the fish in the e xperim ental tanks w ill be observed after Oh (control) 1 2 h, 48h,
84h and 180h intervals. A d ditio na lly, am m onia excretion rate and am m onia q u o tie n t (AQ) w ill be
taken at each interval to help draw conclusions about the fis h ’s adaptive responses to d iffe re n t
am bient salinities. A fte r each interval, fish w ill be removed fro m the ta nk and blood drawn from
them fo r serology. A t the end o f the experim ent, the fishes w ill be dissected and liver, brain, w hite
muscle, g ili and kidney tissues obtained fo r analysis. Analysis w ill involve m easuring o f plasma and
muscle am m onia accum ulation, plasma lactate, liver and muscle glycogen, cortiso l and energy
budget, AQ and Lipid and protein content. It is expected th a t fish would suffer m arked disturbance
o f norm al fu n ctio n s fo llo w in g prolonged exposure to HEA. A d ditio na lly, it is expected th a t am m onia
excretion by the fish w ould increase in an a tte m p t to m aintain the positive am m onia gradient.
However, the levels o f am m onia in plasma and muscles, lactate accum ulation in muscles and the
am m onia q u o tie n t are expected to m arkedly increase. The e xten t to which these changes are
observed w ill depend on salinity, since feeding is universal. High sa lin ity environm ents have been
shown to augm ent am m onia to x ic ity because it facilitates increased concentration o f the NH3
m oiety, which is solely responsible fo r am m onia to x ic ity , in aqueous amm onia. As such, these
changes, and even loss o f fu n ctio n , w ill be expected to be more severe in fish exposed to higher
salinities.
- 31 -
The effects o f a large-scale shoreface no urishm ent on the shallow
coast epibenthos and fish com m unities
De Backer Annelies', Jannes Heusinkveld 2, Harriëtte H olzhauer3, Jan Van Dalfsen3 and Kris Hostens1
1 Institute fo r A g ricu ltu ra l and Fisheries Research, A nim al Sciences Unit, A quatic Environm ent and
Quality, Bio-environm ental Research, A nkerstraat 1, 8400 Oostende, Belgium
E-mail: Annelies.debacker@ ilvo.vlaanderen.be
2 the Fieldwork Company, S tockholm straat 2B, 9723 BC Groningen, the Netherlands
3 Deltares, PO Box 177, 2600 MH Delft, the Netherlands
Climate change and the expected sea level rise made coastal defence a hot to p ic in m ost countries.
A ‘dynam ic’ maintenance o f the coastline w ith natural m aterials, like beach and shoreface
nourishm ent, is often chosen to ensure protection against coastal erosion. Several studies assessed
the ecological im pact o f beach nourishm ent, especially on m acrobenthos. The body o f literature on
the ecological im pact o f shoreface nourishm ent is much smaller, especially when it comes to
epibenthos and demersal fish com m unities o f the shallow coastal zone.
In 2010 and 2011, large-scale nourishm ents on the beach (2 m illion m 3 sand, tw ice) and the
shoreface (4.7M m 3) were undertaken at the o ute r side o f the Am eland Wadden Island (the
Netherlands). The shoreface nourishm ent was perform ed in an ecological manner, w ith a
construction in d iffe re n t phases and the sedim ent resem bling as closely as possible the natural
sediments.
A BACI (B efore/A fter - C on trol/Im p act) design was set up to assess the im pact o f the shoreface
nourishm ent on the epibenthos and dem ersal fish fauna. Beam traw l samples were collected in the
shallow coastal zone along a depth gradient in autum n, once before the shoreface n ourishm ent and
during three consecutive years after suppletion, both in the im pact area and an adjacent reference
area (Schierm onnikoog Wadden Island).
The shallow coastal epibenthos co m m un ity was fu lly dom inated by brown shrim p C rangon crangon,
com m on sw im m ing crab Liocarcinus holsatus and shore crab Carcinus maenas. These are
characteristic species o f a typical coastal e pibenthic com m unity, which is adapted to a h ighly
dynam ic environm ent. No sign ifican t negative effects could be observed o f the shoreface
nourishm ent on the epibenthos com m unity, not even d irectly after the suppletion to o k place. The
demersal fish co m m un ity was dom inated by lesser pipefish Syngnathus rostellatus, gobies
Pomatoschistus sp. and juvenile plaice Pleuronectes platessa. Also, no substantial changes in the
demersal fish co m m un ity were detected, except fo r a small decrease in juvenile plaice in the im pact
area.
It can be stated th a t the ecological approach o f the Am eland shoreface nourishm ent proved to be
successful in both safeguarding the coast from coastal erosion and in preserving nature values.
- 32 -
Standardization at sea: ongoing developm ents fo r EARS event
logging
De Cauwer Karien', Yvan Stojanov1, Jordi Sorribas2, Paolo Diviacco3, Marie-Paule Corre4 and
Alessandro Busato3
1 O perational D irectorate Natural Environm ent, Royal Belgian Institute o f Natural Sciences,
Gulledelle 100, 1200 Brussels, Belgium
E-mail: bmdc@ mumm.ac.be
2 UTM-CSIC, Unidad de Tecnología Marina
Paseo M arítim o de la Barceloneta, 37-49, 08003 Barcelona, Spain
3 OGS, In stitu to Nazionale di Oceanografía e di Geofísica Sperimentale
Borgo G rotta Gigante 4 2 /cn 34010, Trieste, Italy
4 IFREMER, Unité des Navires et Systèmes Embarqués/Service Ingénierie des Logiciels Embarqués
Centre de Brest, BP 70 - 29280 Plouzané, France
W ithin the fram e o f Eurofleets, the developm ent o f com m on softw are tools included the
developm ent o f a reporting tool. EARS, the Eurofleets A u to m a tic Reporting System consists o f an
autom atic data acquisition part, a manual event m odule and reporting fu nctio na litie s. The manual
event m odule aims in the firs t place to have accurately registered m etadata which is o nly possible
when registered as close as possible to the tim e o f m easurem ent or sam pling. Besides com plete
and correct metadata, interoperable inform a tion is o f high im portance fo r fu rth e r use, like
reporting, browsing and dissem ination, over the d iffe re n t cruises and vessels. Existing vocabularies
should be considered as inp ut and vice versa. Especially the SeaDataNet data dictionaries served by
the Natural Environm ent Research Council (NERC) Vocabulary Server are h ighly relevant. By
connecting to these, the standardisation o f m eta-inform ation starts a step sooner: at sea instead o f
at the data centre.
When also looking at the user’s needs, more issues arise. D iffic u lt sam pling conditions and tim e
constraints are im p o rta n t param eters to consider when developing software fo r use on board. User
friendliness is thus o f utm ost im portance: fast entry, m ultilin g ua lism , add itio n o f new term s and
relations, use outside, nested to o ls ... To centralize all meta info rm a tio n in one tool, a clear way fo r
users to enter and retrieve any a dd itional characteristic or param eter accom panying the sample,
observation or m easurem ent according to the specific sam pling or m easurem ent procedure has to
be foreseen.
A th orou g h b rainstorm ing on the characteristics o f an event has resulted in the developm ent o f
event concept. The characteristics and user feedback o f e xisting event loggers like CASINO+ o f
IFREMER and Ours, the Onboard Underway Registration o f Samples, at the O perational Directorate
Natural environm ent have been taken into count. The d iffe re n t com posing concepts as well as the
relations between them have been identified:
■ Subject: the dom ain in which the event takes place, e.g. a seism ic system
■ T o o l: the device th a t produces the event, e.g. a Niskin bottle
■ C ateg ory: the kind o f event ta king place, e.g. sam pling
■ A c tio n : the actual task perform ed, e.g. close bottle
■ C om m en t: a free te x t field th a t is left to the o perator to enter more inform ation
■ A c to r: the person perform ing the action
■ A c tio n _ p ro p e rty : any additional characteristic or param eter accom panying a given action
fo r which the user needs to enter a value onboard e.g. volum e o f w ater centrifuged.
C om m onality between these concepts and e xisting vocabularies has been ide ntifie d. In particular,
the SeaDatanet L05 SeaDataNet device categories can be referred to fo r ‘Subject’, w hile the L22
Seavox device catalogue provides a good list o f m easurem ent devices fo r the ‘T o o l’.
Having events b u ilt over the com bination o f parts, allow high levels o f fle x ib ility but at the same
tim e introduces the risk to get fa r fro m the actual acquisition practices. In o rd e r to avoid errors and
at the same tim e increase user friendliness, it is very im p o rta n t to introduce a mechanism th a t can
constrain choices upon knowledge and e xisting practices. The relations between the instances o f
d iffe re n t concepts are thus im portant.
- 33 -
A t the start o f Eurofleets 1, ‘A c tio n ’ term s have been defined fo r d iffe re n t to ols and disciplines but
it was obvious th a t all aspects o f all disciplines could not be covered since the start. A fle xib le
approach was chosen to prevent users being blocked during the survey. EARS Version 1 is b u ilt in
such a way th a t relationships between term s are being created by scientific experts creating th e ir
personal and d iscipline-specific co n fig u ra tio n tree. New term s can be easily added. A fte r that, an
event is generated by one d ouble-click or drag-and-drop. In fact, an o ntological instance is being
created during the logging o f inform ation.
The o nto log y im plem entation fo r the event logger w ill enable the reference to e xisting controlled
vocabularies or taxonom ies as well as the usage and sharing o f relations between term s as fo r
exam ple the possible actions w ith a given tool. A leap fo rw a rd is ongoing w ith in Eurofleets 2
th ro ug h the fu ll integ ra tion o f the ontology. The so-far logged events are being gathered in an
extended event o nto lo g y in which term s and relations o f e xisting vocabularies are sourced from
th e ir o rigin atin g namespace. As fo llo w in g step, the user interface to enter manual events w ill be
adapted to be based on RDF files (SKOS, OWL) and SPARQL queries.
In ord er to manage the term s, a governance scheme w ill be im plem ented in close collaboration w ith
SeaDataNet. New term s are to be expected as in p u t fo r the NERC Vocabulary Server catalogues. Any
additional list, relations between term s and com m only used local names w ill be served by a
Eurofleets o ntological server and SPARQL end po in t fo r use w ithin the to o l and fo r browsing linked
event inform ation. Contacts and concrete actions are defined to harmonise and establish a comm on
governance beyond the EU w ith in the ODIP project.
- 34-
Buried beneath the sea: m apping the archeological potential o f the
Belgian Continental shelf
De Clercq Maikel, Tine Missiaen and Z urita Hurtado Oscar
Renard Centre o f Marine Geology, Ghent University, Krijgslaan 281, S8, 9000 Ghent, Belgium
E-mail: Maikel.DeClerca@UGent.be
In recent years a large num ber o f archaeological discoveries have been made in the North Sea,
ranging from p rehistoric landscapes to buried archaeological structures as well as artefacts and
palaeontological remains. In view o f the increasing pressure o f com m ercial activities at sea it is
therefore tim e ly to map th is cu ltural heritage before large parts o f it are irreversibly lost. The need
fo r action is fu rth e r stressed by the unique setting o f the Belgian part o f the North Sea (BCP) which
is m arked by a th in layer o f Pleistocene deposits th a t are constantly being reworked in a sedim ent
starved setting, and as a result p rehistoric archaeological artefacts and sites may occur at lim ited
depth and are therefore extrem ely vulnerable.
The proposed research involves the developm ent o f so-called ‘ p otential m aps’ o f the BCP indicating
the se nsitivity o f marine areas to human settlem ent and settlem ent remnants. This w ill be done by
integrating palaeogeographical inform a tion (which buried landscapes and coastlines have been
preserved, w hat did they look like) w ith e xisting archaeological and historical inform ation. This w ill
result in BD geo-archaeological ‘ preservation m odels’ th a t can then be translated into 2D
archaeological ‘ potential m aps’ th a t ide ntify the key archaeological zones in the BCP.
Such potential maps are crucial fo r a sustainable m anagem ent o f the underw ater cultural heritage in
Belgium. They w ill not only help to save tim e and m oney in industrial projects as high risk zones
can be identified in an early stage o f planning, b ut w ill also reduce the risk fo r damage to the
archaeological heritage (or loss, in some cases). A t the same tim e these maps w ill also yield a better
insight into the response o f coastal landscapes to past sea-level changes which w ill allow a better
understanding o f the present-day changes in the coastal area. But m ost o f all the maps w ill
dem onstrate th a t artefacts, settlem ents and whole cultural landscapes can be preserved underwater
- and m oreover th a t th ey provide rich inform a tion on ancient genetics and population m igrations.
- 35 -
JPI Oceans - Joint Program m ing Initiative fo r Healthy and Productive
Seas and Oceans
De Moor W illem 12and Ángel E. M uñiz Pi n ie I la2
1 JPI Oceans Secretariat
Rue du Trône 1BO, 1050 Brussels, Belgium
E-mail: w illem .dem oor@ vliz.be
2 Flanders Marine Institute (VLIZ)
InnovOcean site, Wandelaarkaai 7, B-8400 Oostende, Belgium
E-mail: anqel.m uniz.piniella@ vliz.be
The Joint Program m ing Initiative Healthy and Productive Seas and Oceans (JPI Oceans) (w w w.ioioceans.eu) is a high-level strategic process to provide a long-term integrated approach to marine
and m aritim e research and te chn olo gy developm ent in Europe.
Members o f JPI Oceans invest a pp ro xim a tely EUR 1.8 billion in marine and m aritim e R&D per year.
In its role as a coordination platform , JPI Oceans w ill focus on m aking better and more e fficie n t use
o f these national research budgets, which represent 85% o f the m arine-m aritim e fu n d in g w ithin
Europe. This is in order to reduce the frag m en tatio n , create critical mass and avoid unnecessary
d uplication o f the efforts.
JPI Oceans w ill seek to utilise the broadest range o f fu n d in g sources and instrum ents available at
national, regional and European level. The instrum ents to be used and the type o f actions to be
undertaken w ill depend e ntirely on the challenge, in order to be fit-fo r-pu rpo se. Tools and solutions
could include but are not lim ited to: devising com m on research, innovation, infra structu re and
m on itoring strategies and program m es; developing science-to-policy mechanisms; sharing o f
human capacity, data and infrastructures; th em atic w orkshops (e.g. on m odelling), strategic
w orkshops (e.g. on policy issues) and conferences; jo in t calls; com m on program m es; netw orks o f
organisations; in s titu tio n a l agreements; etc.
JPI Oceans covers all European sea basins w ith 19 p articipating countries: Belgium, Denmark,
Estonia, Finland, France, Germany, Iceland, Ireland, Italy, Lithuania, The Netherlands, Norway,
Poland, Portugal, Romania, Spain, Sweden, T urkey and the United Kingdom . The European
Com m ission is participating as a non-voting m em ber o f the Management Board.
- 36 -
Marine Biotechnology ERA-NET: a European fu n d in g initiative fo r
in te rdisciplin ary research and collaboration
De Raedemaecker Fien
Flanders Marine Institute (VLIZ)
InnovOcean site, W andelaarkaai 7, B-8400 Oostende, Belgium
E-mail: fien.deraedem aecker@ vliz.be
The ERA-NET M arine B iotech (ERA-MBT)'recognises th a t Europe’s marine ecosystems and
organism s are largely unexplored, understudied and underutilized, in spite o f Europe’s access to an
extensive and diverse set o f marine ecosystems, supporting an enorm ous marine biodiversity. This
resource, th ro u g h the coordinated application o f marine biotechnology, has the potential to provide
a m ajor c o n trib u tio n tow ards addressing some o f the m ost pressing societal challenges including
environm ental degradation, human health and delivering sustainable supplies o f food and energy,
am ongst others regarded as the Grand Challenges fo r o u r future.
The ERA-MBT is therefore designed to deliver better co ordination o f relevant national and regional
Research, Technology, D evelopm ent and Innovation (RTDI) program m es in Europe, reducing
fragm entation and d uplication, and paving the way fo r com m on program m es and cooperation in the
provision and use o f research infrastructures. A necessity to make sustainable use o f th is unique
resource.
ERA-MBT's 21 partners w ill w ork w ith stakeholders from in d u stry and organisations to ide ntify
needs and gaps in the value chain fro m research and developm ent, th ro u g h o ptim isin g research
results fo r p ro o f o f concept and industrial uptake and valorisation.
A t least three transnational calls w ill address these challenges, and cooperation w ith
com plem enting activities w ill be explored to add value and pow er to enable the developm ent o f a
h o rizo n ta lly applicable te chn olo gy like marine biotechnology.
In Belgium, close cooperation w ill be established w ith the m embers o f the ‘M ariene B io te c h n o lo g ie
P la tfo rm V la an de re n . This p latform was established early 2012 to increase the v is ib ility o f marine
biotechnology in Flanders where a sig n ifica n t num ber o f scientists are involved in various research
aspects. Also fro m the in d u stry there is a great interest in marine biotechnology research and
industrial applications. This p la tfo rm may c o ntribu te to the general recognition o f marine
biotechnology research, lead to im proved cooperation between experts fro m academia and the
ind ustry and prom ote interdisciplina ry collaborations and netw orking w ith European partners.
References
' h ttp ://w w w .m a rin e b io te c h .e u /
2h ttp ://w w w .m a rie n e -b io te ch n o lo q ie .b e /
- 37 -
New Flemish Aquaculture Platform will develop a long term vision fo r
aquaculture in Flanders
De Raedemaecker Fien1 and Nancy Nevejan2
1 Flanders Marine Institute (VLIZ)
InnovOcean site, Wandelaarkaai 7, B-8400 Oostende, Belgium
E-mail: fien.deraedem aecker@ vliz.be
2 Laboratory fo r A quaculture & A rtem ia Reference Center, D epartm ent o f Anim al Production,
Ghent U niversity (UGent), Rozier 44, B-9000 Gent, Belgium
In Flanders, Belgium, aquaculture production is very lim ited. However, fa r beyond its borders
Flanders is recognized fo r its scientific research and expertise in aquaculture. An aquaculture
platform was set up in 2009 as an inform al netw ork initiative o f Ghent U niversity (UGent) w ith all
key stakeholders in Flanders, e.g. researchers, policy makers, farm ers as well as retailers o f
aquaculture products such as fish, algae and feeds. In September 2012, structural su pp ort was
received fro m the Flemish governm ent when M inister-President Kris Peeters o ffic ia lly launched the
Flemish Aquaculture p la tfo rm 1 The p latform consists o f three entities: the previously established
network, the strategic steering g ro up aquaculture (SSAQ) w ith representatives o f the sector and the
inform a tion desk.
This p latform is a convenient fo ru m fo r inform a tion and knowledge exchange between the many
actors involved: a yearly sym posium is organised to enhance the intra -in du stry contacts, to inform
the public about the latest developm ents in the aquaculture sector, to stim ulate the interaction
between the sector and the public a uth orities and to encourage entrepreneurship. Two successful
sym posia have been organised to date which reached more than hundred people. The p la tfo rm ’s
inform a tion desk w ill give advice to potential sponsors and producers, and m o n ito r national and
international trends and developm ents which w ill be com m unicated th ro ug h the website o f the
platform am ongst others. The SSAQ has, up to now, established fo u r w orking groups whose task it
is, respectively, (i) to design a long term vision fo r aquaculture in Flanders w ith very clear p riorities,
(ii) to id e n tify research activities necessary to su pp ort the sector, (iii) to organise an e fficien t
inform a tion desk and (iv) to p in p o in t legal regulations th a t impede the inflo w o f new young
entrepreneurs interested to start a new aquaculture business in Flanders.
The long term goals o f th is p latform are to stim ulate the aquaculture sector in Flanders and as a
possible result to become less reliant on im ports o f less sustainable aquaculture products.
References
' w w w .aauacultuurvlaanderen.be
- 38-
Spatfall in a changing environm ent: mind the HAB
De Rijcke M aarten1, Michiei B. Vandegehuchte1, Nancy Nevejan2, Julie Vanden Bussche3,
Lynn Vanhaecke3 and Colin R. Janssen1
1 Laboratory o f Environm ental T o xico lo g y and A quatic Ecology
Ghent University, J. Plateaustraat 22, B-9000 Ghent, Belgium
E-mail: m aarten.deriicke@ uqent.be
2 Laboratory o f A quaculture and A rtem ia Reference Center
Ghent University, Rozier 44, B-9000 Ghent, Belgium
3 Laboratory o f Chemical Analysis,
Ghent University, Salisburylaan 133, B-9820 Merelbeke, Belgium
Due to the com bined effect o f overfishing, clim ate change, e utrophication and the dispersal o f
invasive species in the marine environm ent, harm ful algal bloom s (HABs) are steadily increasing in
frequency, inten sity and geographical scale. Yet to date, our understanding o f the effects o f HABs
on the recruitm en t o f marine organism s is lim ited. As shellfish fa rm ing is expected to play a crucial
role in the fu lfilm e n t o f the fu tu re global protein demand, a better understanding o f the risks that
HABs pose to the reproduction and developm ent o f bivalves is needed. This research therefore
aimed to investigate the acute to x ic effects o f harm ful algae and marine to x in s on the larval
viability, developm ent and innate im m une response o f bivalves. To th is end, em bryos o f the model
species M ytilus edulis (blue mussel) were exposed fo r 48 hours to a concentration series o f the
marine to xin s dom oic acid (DA) and okadaic acid (OA) as well as th e ir respective to x in -p ro d u cin g
algae Pseudo-nitzschia m ultiseries and P rorocentrum lim a. We found th a t neither bloom
concentrations o f dom oic acid, nor bloom densities o f P. m ultiseries displayed acute to x ic effects
on the v ia b ility and developm ent o f M. edulis larvae. Okadaic acid on the o the r hand sign ifican tly
reduced the v ia b ility o f veliger larvae at concentrations as low as 37.8pg.l ', which is a concentration
range likely to occur during dense bloom s o f OA producing algae This effect may be related to a
sign ifican t in h ib itio n o f larval protein phosphatases by OA as observed in vitro. P. lim a was not
found to affect the larval developm ent or v ia b ility b ut induced an increase in the phenoloxidase
innate imm une a ctivity which could not be a ttrib u te d to the occurence o f OA in the algae. A sim ilar
increase in PO a ctivity was detected fo r P. m ultiseries. This effect was strain dependent and could
partially be a ttrib u te d to the presence o f DA. As th is is the firs t study to investigate and detect the
activation o f the phenoloxidase innate im m une activity by harm ful algae and marine to xins, the
consequences o f these increases fo r the larval resilience to o the r stressors are unknown. Yet the
change o f the im m une a ctivity com bined w ith the reduced v ia b ility associated w ith OA warrants
closer investigation as HABs could possibly influence natural recruitm en t as well as the hatcherycultured production o f bivalves.
- 39-
New insights in the s tructurin g role o f Lanice conchilega reefs in
intertidal food webs: a focus on epi- and hyperbenthos
Bart De Smet', An-Sofie D’H ondt', Pieterjan V erhelst1, Jérôme Fournier23, Laurent Godet4, Nicolas
Desroy3, M arijn Rabaut1, Magda V in cx1 and Jan Vanaverbeke1
1 D epartm ent o f Biology, Marine Biology Section
Ghent University, Krijgslaan 281 /S8, 9000 Ghent, Belgium
E-mail: badsmet.desm et@ uqent.be
2 CNRS, UMR 7208 BOREA
Muséum National d ’H istoire Naturelle 75231 Paris Cedex 05, France
3 Muséum National d ’H istoire Naturelle
Station Marine de Dinard, 35800 Dinard, France
4 CNRS, UMR 6554 LETG-Nantes G éolittom er
Université de Nantes, 44312 Nantes Cedex 3, France
3 IFREMER Laboratoire Environnem ent et Ressources FBN
CRESCO, 35800 Dinard, France
In recent years, the interest in d isentangling food webs in marine environm ents is grow ing due to
an increasing dem and fo r a sustainable use o f aquatic resources. Moreover, the presence o f healthy
and abundant food webs is crucial to ensure the survival o f species. M onitoring the status and the
trends o f marine food webs is essential in ord er to collect inform a tion needed to assess the current
situation and im plem ent the necessary conservation measures. A marine species which was shown
to be very useful w ith in a conservation co nte xt is Lanice conchilega. This tu be -b u ild in g polychaete
can fo rm dense populations, often called biogenic reefs, which prom ote m acrobenthic co m m un ity
change and constitute feeding grounds fo r secondary consum ers such as fla tfis h and waders.
A lthough L. conchilega is studied quite elaborately, up to now little or no attention has been paid to
the entire intertida l epi- and hyperbenthic com m unities associated w ith the reefs. Therefore, th is is
to our knowledge - the firs t study which focusses on the effect o f L. conchilega reefs on the entire
associated benthic assemblage (i.e. including the macro-, epi- and hyperbenthic com m unity) over a
larger geographic scale. A ll three com m unities were sampled w ith in a L. conchilega reef and control
area at tw o locations in France: the bay o f the M ont Saint-Michel (BMSM) and Boulogne-sur-Mer
(Boulogne).
Independent o f the geographical location, the L. conchilega reef structures all three associated
benthic com m unities, although the e xten t o f the structuring effect varies between them . We suggest
th a t th is is due to the d ifferen tia l dependency o f the macro-, epi-, and hyperbenthic com m unities to
the seafloor. The m acrobenthic com m unity, which is m ost intim ately connected w ith the sedim ent,
is m ost notably affected by the presence o f L. conchilega, w hile the hyperbenthos o f the lower w ater
colum n is the least structured by the reef. The increased abundances o f animals in all three benthic
reef com m unities a ttract and sustain higher tro p h ic levels such as (com m ercial) fish and wader.
Hence, L. conchilega reefs do not o nly affect abundances and d ive rsity but they su bstantially steer
the structure o f the intertida l sandy beach food web including benthic, pelagic and air-borne
com ponents. Moreover, the reef effect is applicable on a larger geographical scale, which is an
im p o rta n t fin d in g tow ards the im plem entation o f widespread conservation measures in the future.
- 40 -
G no to biotic models fo r seabass (D ice n tra rch u s la b ra x ) and Dover
sole (Solea solea)', the chain is only as strong as its weakest link...
De Swaef Evelien', Marlien Schaeck1, Wim Van Den Broeck1, Peter Bossier2; K risto f D ierckens2 and
Annem ie Decostere1
1 D epartm ent o f M orphology, Faculty o f V eterinary Medicine, Ghent University, Salisburylaan 133,
9820 Merelbeke, Belgium
E-mail: evelien.deswaef@ uqent.be
2 Laboratory o f A quaculture and A rtem ia Reference Center, Faculty o f Bioscience Engineering, Ghent
University, Rozier 44, 9000 Ghent, Belgium
The larval phase o f the m ariculture production cycle still suffers from m ajor losses due to
pathogenic agents th a t are m ainly bacterial in nature. Because o f the emergence o f acquired
resistance, one should o p t fo r alternative measures to com bat disease. In th is respect, the use o f
pro bio nts in aquaculture is popular but scien tifically poorly docum ented. Indeed, there is a paucity
o f inform a tion on the mode o f action o f probionts and th e ir interaction w ith the larval aquatic
organism . Only very few reports in th is research dom ain adopted g n o to b io tic host models. This is
nevertheless crucial fo r drawing unequivocal conclusions ta king advantage o f the absence o f
interference by o th e r m icrobial residents. For such a m odel, fu lly bacteria-free eggs are needed as a
starting point. Preferably, the egg and larval m edium should be devoid o f antim icro bial agents not
to restrict the probionts to be screened in term s o f se nsitivity nor to influence egg and larval
physiology.
This study describes the various steps th a t were taken in the pursuit o f p in po intin g such a m odel
fo r seabass (D icentrarchus labrax) b uilding on previously carried o ut research. A d ditio na lly, the
creation o f th is m odel fo r Dover sole (Solea solea) was initiated and is on-going. Various
disinfectants w ith varying concentrations and contact tim es were tested fo r sea bass and are
cu rren tly being evaluated fo r Dover sole aimed at obtaining fu lly sterile eggs w ith an acceptable
hatching rate and no increase in larval m alform ations or m ortality. D iffe re nt larval housing and
m anipulation techniques were evaluated and culture dependent and independent techniques fo r
checking th e ir axenic status a d d itio n a lly are being exam ined. A ll eventually identifie d and ta ilo rmade measures necessary fo r generating an axenic model, need to be carried o u t w ith great
scrutiny. Indeed, it is tru th fu l to state th a t fo r the creation o f fu ll axenity, the chain is o nly as strong
as its weakest link.
- 41 -
Impact o f pile-driving o f offshore m onopile fou nd atio ns on young
sea bass
Debusschere E lisab e th'3, Bert De Coensel2, D om inique A driaens3, Aline Bajek 4, Dick Botteldooren2,
Kris Hostens', Jan Vanaverbeke3, Sofie Vandendriessche', Karl Van G inderdeuren', Magda V incx3
and Steven Degraer63
' Institute fo r A g ricu ltu ra l and Fisheries Research, Anim al Sciences, bio-environm ental research
group. A nkerstraat 1, B-8400 Oostende, Belgium
E-mail: Elisabeth.Debusschere@ ilvo.vlaanderen.be
2 Ghent University, D epartm ent o f Inform ation Technology, Research Group Acoustics, SintPietersnieuwstraat 41, B-9000 Ghent, Belgium
3 Ghent University, Biology Departm ent, Evolutionary M orphology o f Vertebrates,
K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium
4 Marine de Gravelines, Voie des enrochem ents, 59820 Gravelines, France
3 Marine Biology Section, Biology D epartm ent, Ghent University, Krijgslaan 281 S8, B-9000 Ghent,
Belgium
6 O perational D irectorate Natural Environm ent, Marine Ecology and Management Section, Royal
Belgian Institute o f Natural Sciences, Gulledelle 100, B-l 200 Brussel, Belgium and Marine Biology
Section, Biology Departm ent, Ghent University, Krijgslaan 281 S8, 9000 Ghent, Belgium
The construction o f offshore w ind farm s generates im pulsive sounds which are pote ntia lly harm ful
fo r marine fish. To fill the gaps in the assessment o f the lethal and stress sound level thresholds fo r
fish, we carried o ut a ‘worst-case scenario’ field e xperim ent on board o f a piling vessel. European
sea bass o f 68 and 11 5 days old were exposed to pile-driving sound at 45m from the m onopile
driven in the seabed. Fish were exposed to strikes w ith a sound exposure level between 181 and
188dB re 1 pPa2.s, and an acoustic particle velocity level o f 95dB re 1(nm.s ')2.s. The num ber o f
strikes ranged fro m 1739 to 3067, resulting in a cum ulative sound exposure level ranging from 21 5
to 222dB re 1 pPa2.s, and a cum ulative acoustic particle ve locity level o f 130dB re 1(nm.s ')2.s. No
difference in im m ediate or delayed m o rta lity up to 14 days a fte r exposure between co ntrol and
exposed fish groups was found. Fish exposed to pile-driving had a depressed respiration compared
to fish in the co ntrol groups. This so-called hypo-activity displayed by the exposed fish is an
ind icato r fo r stress. The lack o f m o rta lity in o u r field experim ents confirm s the results o f lab
experim ents carried o ut by o th e r researchers. A lthough, the wide d ive rsity in physiology in fish
species com plicates generalizations, the results indicate th a t pile-driving o f w in d m ill m onopile
fo un da tio ns creates sound pressure levels th a t are below the lethal sound threshold fo r juvenile
fish, but above the stress sound threshold, at least fo r juve nile sea bass.
- 42 -
The Flemish c o n trib u tio n s to LifeWatch - A general overview
Dekeyzer Stefanie, Klaas Deneudt, Leen Vandepitte, Annelies G offin, Simon Claus
and Francisco Hernandez
Flanders Marine Institute (VLIZ)
InnovOcean site, W andelaarkaai 7, B-8400 Oostende, Belgium
E-mail: stefanie.dekevzer@ vliz.be
To su pp ort and encourage scientific research on bio dive rsity and ecosystem fu n ctio n in g , Europe
launched LifeWatch w ith in the European Strategy Forum on Research Infrastructures (ESFRI).
LifeWatch fu nctio ns as a central virtu a l laboratory, integrating observatories, databases, web
services and m odelling to ols d istrib u te d th ro u g h o u t Europe.
The Flemish co n trib u tio n s to the LifeWatch infrastructure are coordinated by the Flanders Marine
Institute (VLIZ) and the Research Institute fo r Nature and Forest (INBO).
Flanders is c o n trib u tin g to the central LifeWatch com ponents w ith the construction o f a ta x o n o m ic
b ackbone, which includes ta xon om y access services, a ta xon om ic e diting environm ent, species
occurrence services and catalogue services. These species inform a tion services fa cilita te the
standardization o f species data and the integration o f the d istrib u te d b io dive rsity data repositories
and operating facilities.
On a regional LifeWatch level, Flanders is constructing and m anaging a m arine , fre s h w a te r and
te rre s tria l o b s e rv a to ry . For the marine observatory, the m on thly cam paigns w ith the RV Simon
Stevin were rem odelled to m o n ito r additional param eters and organism groups, a marine station
w ith laboratories was set up, and a dd itional equipm ent (a.o. p hytoplankton flo w cytom eter,
zooscan, video plankton recorder) was purchased by VLIZ. For the freshw ater and te rre stria l
observatory, several projects are coordinated by the INBO, in cooperation w ith VLIZ: a GPS tracking
netw ork fo r large birds, m on itoring o f the Natura 2000 habitats by an Unmanned Aerial System,
acoustic te lem etry o f eel, and remote m on itoring o f ground water.
Furtherm ore, VLIZ and the INBO both have a num ber o f established (biodiversity) d a ta syste m s th a t
co ntribu te considerably to the LifeWatch infrastructure. These systems are constantly being updated
and com plem ented. In ord er to fill some o f the spatial and tem poral gaps in the bio dive rsity data o f
these systems, d a ta a rc h a e o lo g y activities are being carried o ut during the LifeWatch construction
phase (2012-2016). This w ill im prove the accessibility and v is ib ility o f the data fo r the scientific
com m unity.
As a last Flemish c o n trib u tio n to LifeWatch, VLIZ set up an online data portal where scientists can
use several w eb services to standardize, q u a lity control, analyse and visualize th e ir own
bio dive rsity data (h ttp ://life w a tch .b e /d a ta -s e rv ic e s). The web services also assist in the retrieval o f
additional data. These web services fo rm a valuable co n trib u tio n to the data available from the
su pp orting data systems, the ta xon om ic backbone, and the data collected by the observatories and
sensor networks.
During the VLIZ Young Marine Scientists’ Day a few aspects o f the Flemish LifeWatch infrastructure
w ill be hig hligh te d in a series o f anim ated dem onstrations: the use o f the data services, the zooscan
and the sensor netw ork fo r large birds.
- 43 -
Assessing con ne ctivity in young flatfish and its im ple m e nta tion in
fisheries management
Delerue-Ricard Sophie l2, Maria Coscia1, Léo Barbut3, Geneviève Lacroix3, Andreas Vanden Bavière2,
Johan Robbens2 and Filip A.M. V o lckae rt1
1 Laboratory o f Biodiversity and Evolutionary Genomics, Katholieke U niversiteit Leuven,
Ch. D eberiotstraat 32, B-3000 Leuven, Belgium
E-mail: sophie.deleruericard@ bio.kuleuven.be
2 Institute fo r A g ricu ltu ra l and Fisheries Research (ILVO), A nkerstraat 1, B-8400 Oostende, Belgium
3 Royal Belgian Institute o f Natural Sciences (RBINS), DO ‘ N ature’, GulledeIle 100,
B-1200 Brussels, Belgium
Recently, it has been shown th a t com m ercial fisheries ta rg e t specific size/age classes, causing a
loss o f genetic d ive rsity as well as altering life cycles (fisheries-induced evolution). This represents a
serious th re at fo r the fu tu re o f com m ercial stocks. Such features have also been observed in the
North Sea stocks o f sole (Solea solea), which have been overfished in the past 20 years. For
exam ple, heavy fish in g pressure has led to sm aller individuals. Given its com m ercial im portance in
the North Sea fishery, a larger e ffo rt has to be made to preserve th is valuable resource. To improve
sole stock m anagem ent, managers w ould ben efit from an upgraded biological assessment o f
population structure and connectivity patterns. We w ill address the fo llo w in g questions:
1. Does larval dispersal vary in tim e and space?
2. What bio tic and a biotic factors are d riving larval connectivity? And once known,
3. Can we predict the im pact o f changes in physical and biological drivers?
4. Can we define sub-populations based on connectivity patterns?
My research project aims at fillin g those gaps, by focusing on population connectivity at the larval
and postlarval stages. A suite o f 200 h ighly variable SNPs (Single Nucleotide Polymorphism s) and
state-of-the-art genotyping (Illum ina-Veracode) w ill be employed to investigate the population
structure o f sole at a regional scale (<1 50km ) w ith in the North Sea and eastern English Channel.
A d d itio n a l insights w ill be gained by o to lith m icrochem istry, used to trace the m ovem ent o f single
individuals between spawning and nursery grounds. Tem poral v a ria b ility w ill be studied th ro u g h the
com bination o f tw o years o f intensive sam pling and historical datasets spanning the last tw o
decades. Finally, results o f hydrodynam ic m odelling o f larval dispersal w ill be com pared to collected
data in ord er to investigate the role o f selected biotic and a biotic factors in d riving connectivity.
Overall, th is study w ill help the sustainable m anagem ent o f the fish ery by defining sign ifican t
ecological units, while the m olecular m arkers w ill allow tracing any fish present on the m arket to its
o rigin, hence fig h tin g illegal fishing.
- 44-
OceanTeacher Global Academy: OceanTeacher goes global
Delgado Claudia', A d itya Kakodkar' and Peter Pissierssens2
' IOC Project Office fo r IODE, Wandelaarkaai 7 /6 1 , 8400 Oostende, Belgium
E-mail: claudia.delqado@ iode.org
2 UNESCO/IOC Project Office fo r IODE, W andelaarkaai 7 /6 1 , 8400 Oostende, Belgium
E-mail: p.pissierssens@unesco.org
The OceanTeacher Global Academy Project w ill develop a global tra in in g centre netw ork and
u tilize th is netw ork to increase national capacity in coastal and marine knowledge and
management. It w ill do so by (i) pro m o ting the establishm ent o f Regional T raining Centres as well
as th e ir close collaboration th ro ug h advanced inform a tion technology; and (ii) fu rth e r developing
the OceanTeacher Learning System. The OceanTeacher Global Academy w ill change tra in in g from
a ‘ north to s o u th ’ culture to north-south, south-south, and south-north model. Whereas tra in in g was
tra d itio n a lly based on experts fro m developed regions to visit and teach developing country
students, the OceanTeacher Global Academ y w ill prom ote the expertise available in many
developing regions.
Specifically, the OceanTeacher Global Academ y w ill:
i. Promote the establishm ent, and assist w ith the start-up, o f Regional T raining Centres th a t w ill
plan, organize and im plem ent tra in in g courses th a t are o f relevance and serve needs w ithin
th e ir region;
¡i. Promote the use o f local experts as lecturers and tra in in g assistants by the Regional T raining
Centres;
iii. Promote the collaboration between the Regional T raining Centres by enabling (through
advanced inform a tion technology) lecturers fro m m ultiple regions to co ntribu te lectures;
iv. Further develop the OceanTeacher Learning Management System to cover m u ltip le IOC (and
associate) program m es.
The new OceanTeacher Global Academ y w ill build upon and expand the e xisting OceanTeacher
Academ y based at the IOC Project Office fo r IODE in Oostende, Belgium, to a tru ly w orldw ide
tra in in g fa cility. It w ill provide a program m e o f tra in in g courses related to IOC program m es,
c o n trib u tin g to the sustainable managem ent o f oceans and coastal areas w orldw ide, and relevant to
Member States in the regions. A suitable governance structure w ill be created. A ll the
aforem entioned w ill lead to the fo llo w in g b en e fits:
Increase the annual num ber o f trainees th a t can participate in OceanTeacher Academ y courses.
1. Increase the a va ila b ility/in vo lve m e n t and the level o f expertise o f trainers.
2. Alleviate the costs and o the r drawbacks o f long-distance traveling by tra in e rs /le c tu re rs and
trainees.
3. Increase the focus on local issues while keeping a global perspective.
4. Increase self-driven capacity developm ent, including local tra in in g expertise.
The OceanTeacher Global Academ y w ill fu rth e r prom ote collaboration and expertise exchange
th ro ug h new internet-based technologies such as video conferencing, video stream ing etc. between
the Regional T raining Centres (RTCs).
Key Deliverables
1. Regional T raining Centres established, operational and resourced locally (including
infrastructure, processes and managem ent) in, in te r alia, Europe, A frica (IOC-Africa), Latin
Am erica & Caribbean (IOCARIBE), Indian Ocean (IOCINDIO) and Western Pacific (IOC-WESTPAC);
2. C om petent resource persons available in all regions;
3. Well docum ented project governance structure established;
4. Courses organized and content provided th ro ug h the OceanTeacher Learning Management
System (OT LMS) and students trained in topics related to, in te r alia, IODE, IODE/OBIS,
IODE/ICAN, HAB, ICAM, GOOS, Tsunam i, JCOMM, attended by students from one or more regions
sim ultaneously;
5. Annual reports from Regional T raining Centres on progress, including perform ance metrics;
6. Final Im pact assessment o f the Project.
- 45 -
Beneficiaries
■
■
■
■
■
The Project w ill ta rg e t the fo llo w in g train ee s/g ro up s:
Staff o f marine research in stitu tio n s and related facilities,
Staff o f G overnm ent departm ents involved w ith marine science and services,
Marine related practitioners (Governm ent and Private Sector),
U niversity students (marine science and related disciplines).
- 46 -
C onnectivity o f the coral A cro p o ra tenuis in the Spermonde
Archipelago
Demierbe Thibaud, Rosa Maria van der Ven, Puspitaningasih S utrisnoand Mare Kochzius
D epartm ent o f Marine Biology
Vrije U niversiteit Brussel, Pleinlaan 2, B-1050 Brussels, Belgium
E-mail: tdem ierb@ vub.ac.be
Coral reefs are the marine ecosystem w ith the highest bio dive rsity o f marine species. Herm atypic
corals are im p o rta n t ecosystem engineers, providing the three-dim ensional structure o f the habitat.
The d istrib u tio n o f coral reefs is patchy at local scale (among islands) and large scale (across
oceans). Since the adults o f coral reef taxa are sedentary, co nn ectivity among populations is only
possible by dispersal o f planktonic early life h istory stages. Due to anthropogenic im pacts coral
reefs are declining on a global scale and marine protected areas (MPAs) are an im p o rta n t to o l fo r
th e ir conservation. However, due to the patchy nature o f the habitat MPAs should be arranged in
netw orks th a t ensure connectivity among them . This w ill safeguard resilience o f these
m etapopulations by providing new recruits fo r re-colonisation o f disturbed areas.
Insight in the ecology and population dynamics can be used to develop m anagem ent and
restoration strategies. This study w ill investigate connectivity o f the broadcasting herm atypic coral
A cro po ra tenuis on tw o d iffe re n t spatial scales. C onnectivity on a local scale w ill be investigated in
Spermonde Archipelago (Indonesia) w ith a m axim um distance among populations o f about 80km . A
large scale analysis across the Indian Ocean w ill be conducted between populations fro m Indonesia
and populations fro m East Africa. The genetic population structure w ill be investigated by utilising
m icrosatellites. Analysis is based on length polym orphism in Single Sequence Repeats (SSR) o f n on ­
coding DNA regions th a t show a high m utation rate. Sixteen m icrosatellite markers were selected
from literature and are tested fo r polym orphism . The selected m arkers w ill be used in a m u ltip le x
PCR and the length o f the am plicons w ill be measured by capillary electrophoresis. DNA frag m en t
length data w ill be scored w ith the software Genemarker and analysed w ith the program m es
Genealex, FSTAT and STRUCTURE (cluster analysis). The statistical analysis o f the length data w ill
allow us to measure gene flo w and to estim ate connectivity.
- 47 -
One plus one is three: traw lin g differences from m ulti-beam im agery
Depestele Jochen12, Koen Degrendele3, Hans Polet1, Mare Roche 3, lom a Teal4, Bart Vanelslander1
and Adriaan R ijnsdorp4
1 Institute o f A g ricu ltu ra l and Fisheries Research (ILVO)
A nkerstraat 1, 8400 Oostende, Belgium
E-mail: iochen.depestele@ ilvo.vlaanderen.be
2 Marine Biology, Ghent University, Krijgslaan 2 8 1 -S8, B-9000 Ghent, Belgium
3 Federal Public Service Economy, Energy - C ontinental Shelf, Simon Bolivarlaan 30, WTCIII,
1000 Brussel, Belgium
4 Institute fo r Marine Resources and Ecosystem Studies, Wageningen IMARES, PO Box 68, 1 970 AB,
Ijm uiden, the Netherlands
Beam traw ling causes physical d isru p tio n o f the seafloor m ainly due to the effect o f the tic k le r
chains th a t penetrate into the seabed. A b o u t 40 Dutch beam traw lers have recently replaced tic k le r
chains by electrodes as alternative stim ulatio n fo r catching fla tfis h . This g reatly reduced fuel costs
and presum ably reduces benthic impacts. These newly developed fish in g gears (pulse traw ls) were
studied in the EU-FP7 project ‘ Benthis’ using a Before-After C ontrol-Im pact (BACI) setup. The
penetration depth o f the com m ercial ‘ D elm eco’ pulse traw l was investigated and com pared to the
penetration depth o f a conventional 4m com m ercial tic k le r chain beam traw l. Here we focused
specifically o nto the physical alteration to the seabed, illu stra tin g one o f the potentials o f modern
high resolution m ulti-beam echosounder im agery as registered onboard o f the RV Simon Stevin. The
experim ental area was m onitored p rior and a fte r beam traw l disturbance at d iffe re n t tim e intervals
up to 107 hours. A d ditio na lly, the penetration depth o f a single passage o f a tic k le r chain beam
traw l was characterized, as well as m ultiple passages o f a tic k le r chain and pulse traw l. While our
results confirm ed estim ates o f previous studies, subtle differences indicated th a t one beam traw l
disturbance is not the other. Trawl tracks o f m ultiple pulse traw l passages (>3 tim es) reached up to
6cm (median: 1.2 cm) at one day a fte r traw ling , while tic k le r chain traw ling penetrated up to
10.7cm w ith a median o f 2.0cm. In contrast, a single passage o f a tic k le r chain traw l penetrated less
deep (median: 0.9cm , max: 2.9cm). Moreover, u nide ntifie d traw l m arks o f com m ercial beam
traw ling were overall deeper than registered beam traw l disturbances, p ote ntia lly p ointin g at the
use o f yet another type o f com m ercial beam traw l. A lthough the experim ental study area was
relatively shallow (<25m), fading o f traw l marks seemed p rim a rily due to bed and suspended load o f
tid al currents, rather than wave induced currents as wave heights up to 2.5m did not result in faster
fading o f traw l tracks. We therefore conclude th a t the overall significance o f short-term beam
traw ling disturbance is o f considerable im portance in relation to natural disturbance fo r th is study
area, and th a t a d istin ct d iffe re n tia tio n between beam traw l types should be accounted fo r. One plus
one is not ju s t two.
References
w w w.benthis.eu
- 48-
MARES jo in t doctoral program m e on marine ecosystems health and
conservation
Deprez Tim , Pieter Blondeel, Wendy Massart and Magda Vincx
MARES Secretariat, Marine Biology Research Group, Ghent U niversity
Krijgslaan 281/S8 9000 Ghent, Belgium
E-mail: mares@uqent.be
The MARES Doctoral Programme is a jo in t international them atic doctoral program m e th a t was
initiated in 2010. Since then, over 30 young scientists are actively conducting research focused on
the impacts o f human activities on marine ecosystems.
MARES PhD candidates focus on six scientific and applied fields, all dealing w ith marine ecosystems
health and conservation:
1. Future Oceans : tem perature changes - hypoxia - acidification
2. U nderstanding bio dive rsity effects on the fu n c tio n in g o f marine ecosystems
3. Biological invasions
4. Natural Resources : overexp loita tion , fisheries and aquaculture
5. Ocean noise p ollution
6. Flabitat loss, urban developm ent, coastal infrastructures and Marine Spatial Planning
The program m e is funded th ro ug h Erasmus Mundus and is offered by a consortium o f 24 partners,
o rigin atin g fro m 14 d iffe re n t countries. MARES offers each year 9 fellow ships o f 3 year fo r doctoral
researchers. These fellow ships always involve at least 2 partners o f the MARES C onsortium w ith an
o b lig a to ry m o b ility com ponent. The call fo r applications is open between September and December
fo r fellow ships starting at the earliest in September the year after.
Beside its research com ponent, the MARES doctoral program m e has also a tra in in g program m e
which is open to any doctoral student in the field o f marine science. D octoral students enrolling in
th is doctoral tra in in g program m e have access to a wide range o f doctoral tra in in g initiatives, are
invited to annual m eetings and can benefit from e xpe rt guidance fo r both research and train in g
issues.
Website o f the MARES jo in t D octoral Programme: www.m ares-eu.org
- 49-
First MARES Conference Marine Ecosystems Health and Conservation
Deprez Tim , Pieter Blondeel, Wendy Massart and Magda Vincx
MARES Conference C oordination Office, Marine Biology Research Group, Ghent U niversity
Krijgslaan 281/S8 9000 Ghent, Belgium
E-mail: m aresconference@ uqent.be
The firs t international MARES Conference is an initiative from the MARES Doctoral Program. This
jo in t international them atic doctoral program m e was initiated in 2010, and since over 30 young
scientists are actively conducting research focused on the impacts o f human activities on marine
ecosystems. The Mares Conference aims to address the main issues o f marine ecosystems health
and conservation:
1. Future Oceans : tem perature changes - hypoxia - acidification
2. U nderstanding bio dive rsity effects on the fu n c tio n in g o f marine ecosystems
3. Biological invasions
4. Natural Resources : overexp loita tion , fisheries and aquaculture
5. Ocean noise p ollution
6. Flabitat loss, urban developm ent, coastal infrastructures and Marine Spatial Planning
The conference w ill take place from 21 to 27 November 2014 in Olhäo, eastern Algarve, Portugal.
This international and open conference w ill bring to g e th e r scientists from d iffe re n t levels and
disciplines to discuss and address issues about marine ecosystems health and conservation. The
conference w ill be dynamic, m ixing oral presentations, round table discussions and poster and
d ig ita l objects sessions.
Website o f the First Mares Conference: www.m aresconference.eu
Website o f the MARES jo in t D octoral Programme: www.m ares-eu.org
Facebook page o f the Mares Conference: w w w .facebook.com /m aresconference
- 50 -
Towards a user-friendly guide fo r marine education and train in g
Deprez Tim, Danae Kapasakali, Tim tk in t and Magda Vincx
Marine Biology Research Group, D epartm ent o f Biology
Ghent University, Krijgslaan 281/S8, 9000 Ghent, Belgium
E-mail: tim .deprez@ uqent.be
The search fo r marine educational and tra in in g o p p o rtu n itie s is rather challenging. C urrently, the
predom inant source o f inform a tion is the internet, yet th is inform a tion is scattered across several
websites m aking such inquires highly tim e-consum ing. A d ditio na lly, the success o f each o f these
tra in in g initiatives stron gly depends on the advertising and netw orking skills developed by each
hosting e n tity individually. In response to th is shortfall, the Marine@UGent consortium (including
Ghent U niversity and Flanders Marine Institute (VLIZ)) is setting up a portal th a t aims to bring
to g e th e r available marine tra in in g s at a European scale. This portal shall w ork as a single access
point fo r both tra in in g seekers and tra in in g providers. Furtherm ore, it w ill enable the ide ntification
o f tra in in g shortages in certain fie ld s by connecting tra in in g offers w ith tra in in g demands. This
initiative is one o f the prospect goals o f the European Marine Biological Resource Centre (EMBRC), a
d istribu te d Research Infrastructure (Rl), o f which Belgium is an associate partner th ro ug h the
Marine@Ugent C onsortium . EMBRC aspires to interconnect the European marine research
com m unities by upgrading and harm onizing th e ir current infrastructures and services.
A firs t step in the creation o f such a tra in in g portal service is the setup o f a comprehensive
database o f e xistin g marine tra in in g initiatives fo r each country, ranging fro m m aster and doctoral
program m es, to e xpe rt train in g s and specialist courses. A t present, a prototype w ork is being
tested. This prototype database includes data from all Flemish higher education institute s (both
universities and u niversity colleges). Three in itia l criteria were used fo r retrieving a firs t set o f
initiatives fo r th is database: the tra in in g is marine orientated, the language o f instru ction is in
English, and the program m e or the host in s titu tio n is accredited. In the fu tu re the portal shall be
able to expand gradually its content w ith more tra in in g initiatives by including more countries and
by broadening the scope to relevant transferable skill tra in in g s as well as non-accredited initiatives
(for instance, research institute s and industries). The portal aims to (1) become a central advertising
point fo r e xisting and new trainings, (2) o ffe r practical services to trainees and tra in in g organizers
(application and registration), (3) advertise tra in in g grants, and (4) establish marine dedicated Elearning initiatives.
More inform a tion on:
- Prototype o f the tra in in g portal: w w w.em brc.uqent.be
- General inform a tion about EMBRC: www.em brc.eu
- 51 -
Copper to x ic ity in mussels: do salinity, organic m atter and
population histo ry matter?
D eruytter David1, Michiei Vandegehuchte1, Karel De Scham phelaere1, Ronny Blust2
and Colin R. Janssen1
1 Laboratory o f Environm ental T o xico lo g y and A quatic Ecology, D epartm ent o f Applied Ecology and
Environm ental Biology, Ghent University, Jozef Plateaustraat 22, B-9000 Gent, Belgium
E-mail: david.deruvtter@ uqent.be
2 Systemic Physiological & Ecotoxicological Research, D epartm ent o f Biology, U niversity o f Antw erp,
G roenenborgerlaan 171/U 7, B-2020 A ntw erp, Belgium
Salinity and dissolved organic carbon (DOC) are tw o a biotic variables th a t can alter Cu to x ic ity to
marine organism s due to com plexation, spéciation and ion activity. In th is study the sublethal
effects o f prolonged Cu exposure on juvenile transform ed M ytilus edulis were assessed under
d iffe re n t co nd itio ns o f salinity and DOC in 2 populations (North Sea (NS) and Bothnian Sea (BS)).
First, separate experim ents were set up fo r each population. Mussels acclim ated to 5 salinities were
exposed fo r 2 weeks to 18 d iffe re n t salinity/D O C /C u com binations, according to a central
com posite design. A t the end o f the exposure the clearance rate (CR), oxygen consum ption (VO )
and cond itio n index (Cl) were measured. Next, both populations were sim ultaneously assessed
Now DOC was not varied and sa lin ity was identical fo r the tw o populations.
For the NS population, no effect o f salinity on the CR was observed. An increase in DOC s lig h tly
increased the co ntrol CR, but the interaction w ith Cu was m arginal. No DOC effect on CR was
observed in the BS population. However, sa lin ity had a strong positive effect, increasing co ntrol CR
w ith o u t altering Cu to xicity. In the NS population, V 0 2 slig h tly increased w ith increasing DOC
w ith o u t interaction w ith Cu. An increase in salinity increased co ntrol V 0 2 in NS mussels, but in
com bination w ith Cu th is resulted in a faster V 0 2 decline. The effect o f salinity was more
pronounced in the BS population: an increase in sa lin ity increased the co ntrol V 0 2 w ith o u t
interaction w ith Cu. An increase in DOC decreased the control V 0 2 w ith little influence on Cu
to x ic ity in the BS mussels. Salinity and DOC did not affect the Cl in e ither population. The
sim ultaneous e xperim ent yielded sim ilar results.
M. edulis fro m the BS population live near the edge o f the sa lin ity tolerance range. Increasing
m etabolic a ctivity w ith increasing sa lin ity dem onstrates th a t under natural co nd itio ns this
population experiences sa lin ity stress. Nevertheless, when corrected fo r th is change in baseline
m etabolism , BS mussels are as (or less) sensitive than NS mussels. C ontrary to w hat was expected
based on spéciation and com plexation chem istry, an increase in DOC or sa lin ity did not, or only
slightly, decrease the se nsitivity to dissolved Cu. Therefore it seems th a t free Cu ions are not the
only to xic Cu species and Cu-DOC com plexes m ig ht be available fo r uptake by the mussel. This
indicates th a t the current BLM concept is not applicable to M. edulis fo r the measured endpoints.
- 52 -
Electrical traw lin g fo r brown shrim p: Impact on young life stages in
nurseries and spawning areas?
Desender M a rie ke '2, Koen C hiers3, Bart Verschueren2, Hans Polet2, Luc Duchateau4, Puvanendran
V e lm urugu3, Atle M ortensen3 and Annem ie Decostere'
' D epartm ent o f M orphology, Faculty o f V eterinary Medicine, Ghent University, Salisburylaan 133
Merelbeke, Belgium
E-mail: marieke.desender@ uqent.be
2 Institute fo r A g ricu ltu ra l and Fisheries Research (ILVO), Anim al Sciences - Fisheries, A nkerstraat 1,
8400 Oostende, Belgium
3 D epartm ent o f Pathology, Bacteriology & Poultry Diseases, Faculty o f Veterinary Medicine - Ghent
University, Salisburylaan 133 Merelbeke, Belgium
4 D epartm ent o f Com parative physiology and biom etrics, Faculty o f V eterinary Medicine - Ghent
University, Salisburylaan 133 Merelbeke, Belgium
3 The Norwegian Institute o f Food, Fisheries and A quaculture Research (NOFIMA), M uninbakken 913, Breivika PO Box 6122, NO-9291 Trom so, Norway
The application o f electric pulse fields in fish in g gear is considered to be one o f the m ost prom ising
o ptions to increase the su stain ab ility o f dem ersal traw l fisheries. In the pulse traw l fo r brown
shrim p, a low -in te nsity electrical field selectively induces a startle response in the shrim ps. Other
benthic organism s are left untouched and can
escape underneath a hovering
traw l. Extensive
testing o f th is device in the North Sea revealed
a discard reduction o f 35-65%
and less bottom
contact o f 80%. In a dd itio n, the results o f the h ithe rto perform ed analyses o f the exposure and
survival experim ents seem to indicate th a t the use o f these pulses has no im m ediate harm ful effects
on d iffe re n t a du lt fish and invertebrate species.
However the im pact on o the r marine life stages is still unknow n. As brown shrim p are caught in
coastal zones and estuaries, im p o rta n t nurseries or spawning areas fo r a wide
range o f marine
species, e le ctrofish ing over these grounds could therefore harm embryos, larvae and juve niles if
exposed during th e ir m ost sensitive stages.
As cod (Cadus m orhua) was already considered to be a vulnerable species to electrical pulses (De
Haan et. al., 2009) experim ents were carried o ut on d iffe re n t developm ental stages o f this
roundfish species in cooperation w ith the cod breeding centre o f Nofim a in Trom so, Norway. Three
stages o f em bryonated eggs, fo u r larval stages and one juvenile stage were exposed to a
hom ogeneous w orst case electrical field o f 150V .m -l d urin g 5 seconds. Survival, in ju ry and
developm ent were macro- and m icroscopically inspected until 2 weeks after m etam orphosis. All
experim ents were perform ed in trip lica te and the appropriate controls were included.
No sign ifican t density or hatching differences could be established between co ntrol and exposed
groups in the d iffe re n t egg stages. Also in the juve nile stage no difference in m o rta lity was
observed. In the larval stages there was no sign ifican t effect o f the electrical pulses on survival in
the stages exposed im m ediately after hatching, the endogeneous stage eating rotife rs and the
m etam orphosing stage. However in the exogeneous larval stage, when the yo lk is com pletely
depleted and larvae have to actively eat A rtem ia, there was a sign ifican t difference w ith the exposed
animals e xh ib itin g a higher m ortality. On all sampled larvae a m orphological analysis is on-going
which may reveal differences in yo lk resorption and grow th or may reveal phenomena such as
starvation or deform ation.
References
De Haan D., B. van Marlen, T.S. Kristiansen and J.E. Fosseidengen. 2009. The effect o f pulse
stim ulatio n on biota - Research in relation to ICES advice - Progress report on the effects on
cod. IMARES report C 09 8/08 : 25pp.
- 53 -
Belgian marine m o n ito rin g data at the BMDC
Devolder Mia, Karien De Cauwer, Ruth Lagring, Serge Scory and Yvan Stojanov
Royal Belgian Institute o f Natural Sciences, O perational D irectorate Natural environm ent
G u I lede Ile 100, 1200 Brussels, Belgium
E-mail: bmdc@ mumm.ac.be
The Belgian Marine Data Centre (BMDC, w w w .m um m .ac.be/datacentre) serves as national rep osito ry
and processing centre fo r marine and environm ental data, collected by d iffe re n t research institutes
and university laboratories in the fram e w o rk o f national and international research and m onitoring
program m es. In the fram e o f the m on itoring activities developed by the Belgian federal
adm in istratio n, like those bound to the OSPAR C onvention, to the Water Framework Directive and to
the environm ental m on itoring o f the offshore w indfarm s, the BMDC gathers, dissem inates and
reports the required data in a predeterm ined fo rm a t to the com petent authorities.
Systematic m on itoring in the Belgian C ontinental Shelf started already in 1978 in the fram e o f
OSPAR. Nowadays, m easurem ents are also perform ed fo r the Water Framework Directive.
C ontam ination in d iffe re n t com partm ents, seawater, sedim ent, biota are measured as well as
eutrophication param eters in the w ater column.
A specific m on itoring program m e to assess the potential impacts o f the wind farm project on the
marine environm ent in the Belgian C ontinental Shelf (BCS) (Degraer et al., 2013) started in 2005.
The program m e involves the study o f hydrodynam ic and sedim entological (turb id ity, currents,
bathym etric evolution), and biological (epifouling com m unity, macro- and epibenthos, plankton,
seabirds and marine mammals) aspects o f the marine environm ent. To cover all necessary scientific
expertise, MUMM collaborates w ith several institutes.
The results are stored in IDOD, ‘the integrated database on the q u a lity o f the marine e nviro n m e nt’.
This database contains the results o f in situ measurements, observations and laboratory analyses o f
the d iffe re n t marine com partm ents as well as the metadata referring to high-frequency data series
(e.g. tim e series, trajectories). Most o f the datasets relate to the Belgian C ontinental Shelf, the
Scheldt estuary and its surrounding areas.
Historical data collected during the firs t phases o f modern Belgian oceanography, Project Sea (1 9701976) and the Concerted Research A ctions (1977-1982), have been d ig itize d and im ported during
the Belspo project PMPZ-DBII. Long tim e series, w ith the focus on contam ination, e utrophication and
acidification are the subject o f the recently started project 4DEMON (‘4 Decades o f Belgian Marine
M onitoring: u p liftin g historical data to to d a y ’s needs’, BRAIN-be program m e o f Belspo). These data
w ill be extended, intercalibrated and valorised in cooperation w ith 4 experienced partners, namely
ILVO, VLIZ, UGent-Laboratory o f P rotistology and A quatic Ecology, and ULg-Chemical Oceanography
Unit.
Data are dissem inated via w w w .m um m .ac.be/datacentre , but are also d istribu te d via the European
portals Seadatanet (w w w .seadatanet.org) and Geoseas (www.qeo-seas.eu). As partner o f the
European FP7 project Geo-Seas, MUMM archives geological and geophysical data (e.g. BCS related
m ultibeam data) according to international standards w ith regards to vocabularies and form ats.
As National Oceanographic Data Centre (NODC), the BMDC is partner o f the SeaDataNet
infrastructure. This infra structu re (now supported by the EU FP7 ‘SeaDataNet 2 ’ project) has the aim
to make marine data easily accessible via a unique interface, at a pan-European level. The data is
made discoverable, and then retrievable, via the Common Data Index (CDI) service which is
interlinked to the o the r metadata services, like Cruise Summary Reports (CSR), Marine Research
O rganizations (EDMO) and Marine Data Sets General D escriptions (EDMED).
References
Degraer S., R. Brabant and B. Rumes (Eds.) 2013. Environm ental impacts o f offshore w ind farm s in
the Belgian part o f the North Sea: Learning from the past to optim ise fu tu re m on itoring
program m es. Royal Belgian Institute o f Natural Sciences, O perational D irectorate Natural
Environm ent, Marine Ecology and Management Section. 239pp.
- 54-
Linking human activities to eu trophication along the river-ocean
con tinu um w ith an ecological model
Dulière Valérie1, Nathalie Gypens2, Christiane Lancelot2, Patrick Luyten1, Xavier D esm it1
and Geneviève Lacroix1
1 O perational D irectorate Natural Environm ent (OD Nature), Royal Belgian Institute o f Natural
Sciences (RBINS), Gulledelle 100, 1200 Brussels, Belgium
E-mail: v.duliere@ m um m .ac.be
2 Ecology o f A quatic Systems, Université Libre de Bruxelles
CP221, boulevard du Triom phe, 1050 Bruxelles, Belgium
A b o u t 15 years ago, the jo in t expertise o f RBINS and ULB led to the coupling o f a hydrodynam ic
model (COHERENS; Luyten e t al., 1999) w ith an ecological m odel (MIRO; Lancelot et al., 2005). MIRO
is able to sim ulate the annual cycle o f carbon, inorganic (NH4, N 03, P04, Si02) and organic
nutrients, phyto pla nkton (diatom s, nanoflagellates, Phaeocystis), bacteria and Zooplankton
(m icrozooplankton, copepods). The coupled model has been set up to cover the Southern North Sea
and the English Channel (Lacroix e t al., 2007). It has already proven its usefulness, fo r instance, in
eutrophication related studies (Lenhart et al. 2010) or to assess the bio tic and a biotic co n tro l o f C02
fluxes in coastal waters (Gypens e ta !., 2011).
Very recently, MIRO&CO has been upgraded to its second version (MIRO&CO M2). The code has been
com pletely rew ritten in FORTRAN 90 and new features were made available. Oxygen is now
e x p lic itly included as a model state variable and a tracer m ethod is cu rren tly being im plem ented
into the m odel. Realistic weather and river fo rcin g are used to force the model. N utrients inp ut are
done via the main rivers, ocean open boundaries and atm ospheric wet and d ry depositions.
The new im plem entation o f the marine ecological m odel w ill be presented. The m odel potential in
term s o f providing relevant inform a tion to marine scientific and m anagem ent issues w ill be
discussed. This w ill be illu strate d w ith the help o f m odel results.
References
Gypens N., G. Lacroix, C. Lancelot and A.M. Borges. 2011. Seasonal and inter-annual v a ria b ility o f
air-sea C02 flu xes and seawater carbonate chem istry in the Southern North Sea. Progress in
Oceanography 88:59-77.
Lacroix G., K.G. Ruddick, Y. Par, N. Gypens and C. Lancelot. 2007. Validation o f the 3D
biogeochem ical m odel MIRO&CO w ith field n u trie n t and p hytoplankton data and MERIS-derived
surface chlo ro p hyll a images. Journal o f Marine Systems 64 (1 -4 ):6 6 -8 8 .
Lancelot C., Y. Spitz, N. Gypens, K. Ruddick, S. Becquevort, V. Rousseau, G. Lacroix and G. Billen.
2005. M odelling diatom and Phaeocystis bloom s and n utrien t cycles in the Southern Bight o f
the North Sea: the MIRO model. Marine Ecology Progress Series 289:63-78.
Lenhart H.J., D.K. Mills, H. Baretta-Bekker, S.M. Van Leuwen,J. Van der Molen, J.W. Barreta, M. Blaas,
X, Desmit, W. Kühn, G. Lacroix, H.J. Los, A. Menesguen, R. Neves, R. Proctor, P. Ruardij, M.D.
Skogen, A. Vanhoutte-Brunier, M.T. Villars and S.L. Wakelin. 2010. Predicting the consequences
o f n utrien t reduction on the e utrophication status o f the North Sea. Journal o f Marine Systems
81:148-170.
Luyten P.J., J.E. Jones, R. Proctor, A. Tabor, P. T ett and K. W ild-Alien. 1999. COHERENS
docum entation: a coupled hydrodynam ical-ecological m odel fo r regional and sh elf seas: user
docum entation, MUMM, Brussels.
- 55 -
Seasonality o f nearshore marine snow in the southern North Sea
Fettweis M ichael1, M atthias Baeye1, D im itry Van der Zande', Dries Van den Eynde1
and B yu ng joo n Lee2
1 O perational D irectorate Natural Environment, Royal Belgian Institute o f Natural Sciences
Gulledelle 100, B-1200 Brussels, Belgium
E-mail: m .fettweis@ m um m .ac.be
2 School o f C onstructional and Environm ental Engineering, Kyungpook National University, 2559
Gyeongsang-daero, Sangju, Gyeongbuk, 742-711, Republic o f Korea
The suspended particulate m atter (SPM) concentration in the high tu rb id ity zones o f the southern
North Sea is inversely correlated w ith chlo ro p hyll (Chi) concentration. During w in te r SPM
concentration is high and Chi concentration low and vice versa during summ er. This seasonality has
often been associated w ith seasonal pattern in w ind fo rcin g. However, the decrease in SPM
concentration corresponds well w ith the spring algae bloom . Does the decrease o f SPM
concentration caused by changing wind conditions, cause the start o f algae bloom , or does the
algae bloom decrease SPM concentration th ro ug h enhanced flo cculatio n and deposition? In o rd e r to
answer the question, m easurem ents from 2011 o f particle size d is trib u tio n (PSD), SPM and Chi
concentration from the southern North Sea have been analysed. The results indicate th a t the
frequency o f occurrence o f m acroflocs has a seasonal signal and not its size. The data from a h ighly
tu rb id coastal zone suggest th a t the m axim um size o f the m acroflocs is controlled by turbulence
and the available flo cculatio n tim e during a tid al cycle, but the strength o f the m acroflocs is by the
availab ility o f sticky organic substances associated w ith enhanced prim ary production durin g spring
and summ er. The results h ig h lig h t the s h ift o f m ainly m icroflocs and flo cculi in w in te r tow ards more
m uddy marine snow w ith larger am ounts o f m acroflocs in spring and summer. The m acroflocs w ill
reduce the SPM concentrations in the tu rb id ity m axim um area as they settle faster. Consequently,
the SPM concentration decreases and the lig h t co ndition increases in the surface layer enhancing
fu rth e r algae grow th.
- 56 -
The effects o f an thropogenic stressors on the food q u a lity in
estuarine systems
Filim onova V a le n tin a '23, Marleen De T ro ch 2, Fernando Gonçalves3 and Ana M.M. G onçalves'3
' IMAR-CMA, D epartm ent o f Life Sciences, U niversity o f Coim bra, Coim bra, Portugal
E-mail: va lentina.m .filim onova@ qm ail.com : valentina.filim inova@ uqent.be
2 Marine Biology Section, Biology Departm ent, Ghent University, Krijgslaan 281-S8,
B-9000 Gent, Belgium
3 D epartm ent o f Biology & CESAM, U niversity o f Aveiro, Aveiro, Portugal
During the last decades discharge o f contam inants is one o f the high concerns to the marine
scientific co m m un ity o f the th re at and adverse effects it may cause in aquatic ecosystems (M cKnight
e t al., 2012). Little is known about how natural ecosystems respond to chronic exposure to
pollutants, many o f which, especially metals, are non-degradable and therefore accum ulate in
nature. A n th ro po g en ic pressures often decrease the health and sta b ility o f ecosystems, although
the precise effects o f these stressors on the biochem ical com ponents o f living organism s and th e ir
interactions remain largely unknow n (Gonçalves et al., 2012 a; H olliday e t al., 2009). Despite the
extensive literature on anthropogenic pressures, a more fu nctio na l approach to trace changes in
food webs due to the m odified biochem ical com position o f interacting species is lacking so far.
N utrients, m ainly lipids and proteins, are involved in many vital fu n ctio n s o f aquatic individuals
(Arts e t al., 2001; Hibbein et al., 2006; SanGiovanni and Chew 2005; Teilum et al., 2011). Since
some o f them can o nly be obtained from food and therefore referred to as ‘essential n u trie n ts ’ , they
proved to be useful tro p h ic m arkers (De Troch e t al., 201 2, Kelly and Scheibling, 2012) in o rd e r to
detect changes in the efficience o f energy tran sfe r between tro p h ic levels. T rophic biom arkers as
fa tty acid (FA) profiles, protein q ua ntifica tion and enzym atic activity w ill be used to te st fo r potential
effects o f pollutants as stressors on the energy flo w between tw o tro p h ic levels i.e. prim ary
producers and prim ary consum ers. Integrating m ultiple specific biom arkers to assess biochem ical
responses o f estuarine species provides a pow erful to o l to q u a n tify the health status o f an
individual in response to anthropogenic stressors (Masclaux et al., 201 2).
This Mares PhD study (2014-2016) aims to address the influence o f hum an-induced environm ental
changes on fu nctio na l (biochem ical, in relation to food web interactions) com position o f tw o main
estuarine planktonic groups in a southern European estuary (e.g. Mondego Estuary, Portugal) by
means o f (trophic) biom arkers.
We w ill focus on p hytoplankton and Zooplankton as th ey are w idely used in the dete rm ina tion o f
environm ental impacts due to th e ir key position in the grazing food chain (Gonçalves e t al., 2012 a,
b, c). Two main representatives o f both tro p h ic levels (key species as e.g. the diatom Thalassiosira
w eissflogii and the copepod A c a rtia tonsa) w ill be used to constitute a simple tro p h ic food chain
under lab conditions.
Copper and herbicide Primextra® Gold TZ w ill be used as contam inants. The assessment w ill include
individual exposure o f toxicants and th e ir bifactorial com binations as well. This w ill allow to
conduct controlled lab experim ents in order to determ ine and q u a n tify the individual and com bined
effects o f anthropogenic stressors.
According to experim ental data about to x ic ity acquired in th is project, along w ith o the r data from
literature, an e cotoxicological m odel based on biochem ical com position o f estuarine species w ill be
b u ilt in collaboration w ith Prof. Dr. Frederik De Laender (University o f Namur, Belgium). This model
aims to predict potential changes in aquatic food web, and thus in food quality, caused by
anthropogenic activities, and to determ ine the level and type o f p ollutio n in estuarine systems
susceptible o f causing changes in species’ biochem ical com position.
References
A rts M.T., R.G. Ackm an and B.J. Holub. 2001. ‘ Essential fa tty acids’ in aquatic ecosystems: a crucial
link between d iet and human health and evolution. Canadian Journal o f Fisheries and A quatic
Sciences 58:122 - 137.
De Troch M., P. Boeckx, C. Cnudde, D. Van Gansbeke, A. Vanreusel, M. Vincx and M.J. Caramujo.
201 2. Bioconversion o f fa tty acids at the basis o f marine food webs: insights fro m a com poundspecific stable isotope analysis. Marine Ecology Progress Series 465:53-67.
Gonçalves A .M.M., U.M. A ze iteiro, M.A. Pardal and M. De Troch. 201 2a. Fatty acid p ro filin g reveals
seasonal and spatial shifts in Zooplankton diet in a tem perate estuary. Estuarine, Coastal and
Shelf Science 109:70-80.
- 57 -
Gonçalves A .M .M., M.A. Pardal, S.C. Marques., S. Mendes, M.J. Fernández- Gómez, M.P. GalindoV illa rd o n , U.M. A zeiteiro. 201 2b. Diel vertical behavior o f Copepoda co m m un ity (naupliar,
copepodites and adults) at the boundary o f a tem perate estuary and coastal waters. Estuarine,
Coastal and Shelf Science 9 8 :1 6-3 0.
Gonçalves A .M.M., M.A. Pardal, S.C. Marques, S. Mendes, .M.J. Fernández- Gómez, M .P. GalindoV illardó n , U.M. A zeiteiro. 201 2c. Responses o f Copepoda life -h isto ry stages to clim atic
va ria b ility in a southern-European tem perate estuary. Zoological Studies 51 (3 ):3 2 1 -335.
HibbelnJ.R., T.A. Ferguson and T.L. Blasbalg. 2006. Omega-3 fa tty acid deficiencies in
neurodevelopm ent, aggression and autonom ic dysregulation: o p p o rtu n itie s fo r intervention.
International Review o f Psychiatry 18:107-118.
H olliday D.K., A.A. Elskus and W.M. Roosenburg. 2009. Impacts o f m ultiple stressors on grow th and
m etabolic rate o f Malaclemys terrapin. Environm ental T oxico lo g y and C hem istry 28:338-345.
KellyJ.R. and R.E. Scheibling. 2012. Fatty acids as die ta ry tracers in benthic food webs. Marine
Ecology Progress Series 446:1-22.
Masclaux H., A. Bec, M.J. Kainz, F. Perrière, C. Desvilettes and G. Bourdier. 2012. A ccum ulation o f
polyunsaturated fa tty acids by cladocerans: effects o f taxonom y, tem perature and food.
Freshwater Biology 57: 696-703.
McKnight U.S., J.J. Rasmussen, B. Kronvang, P.L. Bjerg and P.J. Binning. 2012. Integrated assessment
o f the im pact o f chemical stressors on surface w ater ecosystems. Science o f the Total
Environm ent 427-428:31 9-331.
SanGiovanni J.P. and E.Y. Chew. 2005. The role o f omega-3 long-chain polyunsaturated fa tty acids in
health and disease o f the retina. Progress in Retinal and Eye Research 2 4 :8 7 -1 3 8 .
Teilum K., J.G. Olsen and B.B. Kragehund. 2011. Protein stability, fle x ib ility and fu nctio n.
Biochimica et Biophysica Acta 1814:969 - 976.
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Genetic structure and connectivity assessment w ith hyperpo lym o rph ic data in a high-dispersal potential m ollu sk in North
A tla ntic
Fourdrilis Séverine, Vanya Prévôt, Marine M onjardez and T h ie rry Backeljau
Royal Belgian Institute o f Natural Sciences
Brussels, Belgium
E-mail: sfourdrilis@ naturalsciences.be
C onnectivity is a critical com ponent o f marine ecology to address the questions ‘ how fa r do larvae
disperse?’ and ‘ how much do larvae disperse?’ But m easuring connectivity is c u rre n tly a m ajor
challenge because o f the d iffic u lty to physically m o n ito r larvae - tin y propagules spreading in an
open and wide marine m edium (Buston and D’Aloia, 2013). However, genetic co nn ectivity is an
alternative and pow erful approach using genetic m etrics to provide indirect m easurem ent o f
connectivity by sam pling a du lt specimens w ith o u t the constraint o f d irectly m on itoring larvae
(Hellberg e t al.', 2002). Moreover, it allows integration o f co nn ectivity over many generations at
evolutionary tim e-scales. Estimates are therefore more than an average picture o f contem porary
gene flow , th ey are a picture o f the cum ulative effect o f gene flo w over tem poral and spatial scales.
Genetic co nn ectivity also provides the lowest possible level o f genetic resolution by com paring
individuals at the nucleotide level (Kool e t al., 2013). To have an understanding o f the spatial scales
over which populations o f marine planktonic-dispersing invertebrates are connected by larval
dispersal in N orth A tlantic, we assess genetic connectivity o f the widespread periw inkle M elarhaphe
neritoides. Its long-lived planktonic larval phase lasts 4-8 weeks, th is species is then assumed to
have a high dispersal potential and to be genetically hom ogeneous over large areas. Previous
genetic studies have shown very little to no broad-scale or fine-scale population genetic
d iffe re n tia tio n along the European coast (Johannesson, 1992; Cuña e t al., 2011 ; Garcia et al., 2013).
Our study aims to reinforce these observations and to validate the absence o f genetic d iffe re n tia tio n
o f M. neritoides (1) on a com plete distance range 1-5000km , (2) by intensifying the sam pling e ffo rt
o f specimens and m arkers, (3) and by properly handling highly p olym orphic genetic data to avoid
the known potential bias in genetic d iffe re n tia tio n estim ates (Wright, 1978). We also go fu rth e r and
provide new genetic connectivity data fo r M. neritoides in North A tlantic, inferred from reliable
genetic d iffe re n tia tio n estim ates or using the coalescent. Despite a rem arkably high genetic
d ive rsity found in M. neritoides, results show very weak genetic d iffe re n tia tio n at the three mtDNA
COI, 16S and Cytb loci. Gene flo w is consequently very high between population along the European
coastline as well as w ith the remote Azores archipelago.
References
Buston P.M., C.C .D’Aloia. 2013. Marine ecology: reaping the benefits o f local dispersal. C urrent
Biology 2 3 (9 ):3 5 1-353.
Hellberg M.E., R.S. Burton, J.E. Neigel and S.R Palumbi. 2002. Genetic assessment o f connectivity
among marine populations. Bulletin o f Marine Science 7 0 (l)s u p p l.:2 7 3 -2 9 0 .
Kool J.T., A. Moilanen and E.A. Trem l. 201 3. Population connectivity: recent advances and new
perspectives. Landscape Ecology 28:165-1 85.
Johannesson K. 1 992. Genetic va ria b ility and large scale d iffe re n tia tio n in tw o species o f litto rin id
gastropods w ith p la n kto tro p h ic developm ent, L itto rin a litto re a (L.) and M elarhaphe (Littorina)
neritoides (L.) (Prosobranchia: Littorinacea), w ith notes on a mass occurrence o f M. neritoides in
Sweden. Biological Journal o f the Linnean Society 47:285-299.
Cuña V., M. Saura, H. Quesada and E. Rolàn-Alvarez. 2011. Extensive m icro-geographical shell
polym orphism in a p la n kto tro p h ic marine intertida l snail. Marine Ecology Progress Series
427:133-143.
Garcia S.D., A.P. Diz, A. Sà-Pinto and E. Rolàn-Alvarez. 201 3. Proteomic and m orphological
divergence in m icro-allopatric m orphotypes o f M elarhaphe neritoides in the absence o f genetic
d iffe re n tia tio n . Marine Ecology Progress Series 475:145-1 53.
W right S. 1978. V a ria b ility w ith in and among natural populations. In: Evolution and the Genetics o f
Populations. U niversity o f Chicago Press, Chicago, IL, Vol. 4.
- 59-
Regeneration o f a mangrove forest in a nature reserve and
pa rticip atory m anagem ent con text (Mida Creek, Kenya)
Frank Céline1, James Kairo3, Mohamed O.S. M oham ed4, Nico Koedam' and Farid D ahdouh-G uebas'2
' Laboratory o f Plant Biology and Nature Management, Mangrove Management Group,
Vrije U niversiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
E-mail: celine.frank@ vub.ac.be
2 Laboratoire d'Écologie des Systèmes et Gestion des Ressources, Départem ent de Biologie des
Organismes, Université Libre de Bruxelles (ULB), Campus du Solbosch, B, 2E, office 65, CP169,
Avenue F.D. Roosevelt 50, B-1050 Bruxelles, Belgique
3 Kenya Marine and Fisheries Research Institute, PO Box 81651, Mombasa, Kenya
4 Kenya W ildlife Service, PO Box 82144 - 80100, Mombasa, Kenya
Mida Creek m angrove fo re st is part o f w hat was the firs t marine protected area in Kenya,
established in 1 968 and am ongst the firs t in Africa. This establishm ent follow ed a grow ing pressure
o f human a ctivity on the forest, m ainly linked w ith the high wood requirem ents o f the grow ing
to urism sector. Ten years later, the mangrove was also included in the Arabuko-Sokoke Nature
Reserve, which is to da y the largest protected frag m en t o f a fo re st mosaic th a t once stretched from
southern Somalia to northern Mozambique.
In addition to th is national protection, Mida Creek also benefits fro m the international status o f
‘ Man and Biosphere Reserve’ fro m UNESCO and the ‘ Im po rtan t Bird A re a ’ by Bird Life International in
2001.
Those m ultiple protection statuses represent valuable legal to ols in helping restoration o f this
hum an-im pacted fo re st but in practice it also lead to conflicts o f interest between stakeholders who
share m anagem ent and resources.
A fte r being excluded o f the mangrove m anagem ent fo r m any years, the local population which
depends to a large degree on the mangrove resources, is fin a lly o ffic ia lly recognized as one o f the
stakeholders o f the forests, th ro ug h a governm ental act signed in 2005 (Forest A ct 2005, revised in
2012). However, the im plem entation o f th a t act is slow and issues o f tru s t and co rrup tion are still
an im p o rta n t obstacle to the e ffo rts given to conservation and restoration.
Our study aims at evaluating changes occurring in term s o f m anagem ent and fo re st regeneration,
by the use o f socio-ecological indicators. The firs t ind icato r concerns the new m anagem ent
approach im plem entation and the level o f co m m un ity involvem ent into restoration and conservation
projects. The second indicator is an assessment o f m angrove regeneration patterns and a rtificial
restoration (i.e. plantations) success.
The tools used to measure those indicators were: interviews w ith key-inform ants and population,
policy analysis, satellite images and botanical surveys in plantations.
Our firs t results show th a t involvem ent o f local population is perceived as low and partial. 32% o f
the respondents cited the co m m un ity as one o f the fo re s t’s managers, w hile state organizations
were cited in 91% o f the cases. Only 20% o f people interviewed were c u rren tly involved in a
mangrove conservation-related project, while dependence on the m angrove and its resources is still
high am ongst the population. A lternative activities such as bee-keeping or Casuarina e qu istifolia
planting exist and are spreading but still often considered as marginal.
Concerning the m angrove forest, an increase in tree coverage from 2000 to 2013 w ith o ld er and
bigger trees was observed fro m the maps. However, low success and poor managem ent o f the
plantations ham per the idea th a t th ey could be used in the fu tu re by the com m unity.
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Are the mangroves o f Sokone (Sine Saloum, Senegal) utilized in a
sustainable way? An analysis m erging socio-ecologic interviews w ith
vegetation science
Géoris Sylvestre', Djedje Kungula M akoso' and Farid D ahdouh-G uebas'23
' Laboratory o f Systems Ecology and Resource Management, Université Libre de Bruxelles - ULB,
Avenue Franklin D. Roosevelt 50, CPI 2 6 4 /1 , B-1050 Brussels, Belgium
E-mail: fdahdouh@ ulb.ac.be
2 Laboratory o f Plant Biology and Nature Management. Vrije U niversiteit Brussel - VUB, Pleinlaan 2,
B-1050 Brussels, Belgium
3 This study was in part financed by the Zemst-Sokone city link.
T ogether w ith the Casamance, the Sine Saloum Delta is one o f the m ost iconic mangrove forests in
West-Africa. Yet, the persistence o f the mangrove fo re st is threatened by frag m en tatio n , and so is
the livelihood gained th ro ug h fish in g activities, which is jeo pa rdized by sedim entation o f mangrove
creeks (Kungula Makoso e ta !., 2014, th is issue).
This study evaluates m angrove ecosystem goods and services beneficial to fis h e r fo lk com m unities
living around the city o f Sokone in Senegal’s Sine Saloum Delta, and aims at a return to the users on
the value o f the mangroves fo re st and on its governance (biological and bio-cultural conservation).
We used sem i-structured questionnaires on the use o f the m angrove fo r tim b e r and fuelw ood, as
non-tim ber fo re st products fo r instance fo r ethnom edicinal properties o f some mangrove species,
fo r fishery-related activities, etc. We compared logging activities in heavily im pacted and less
impacted fo re st zones in vegetation plots o f 100m 2 in which we recorded various vegetation
characteristics (Kungula Makoso e ta !., 2014, th is issue).
Prelim inary results o f th is on-going study indicate th a t local people have a d iffe re n tia l effect on
mangroves located closer or fa rth e r from the city. Wood requirem ents are expected to increase due
to population grow th and d e ficit o f means o f co ntrol and managem ent o f natural resources.
References
Kungula Makoso, D., S. Géoris, K. Q u istho ud t and F. Dahdouh-Guebas. 2014. A n thropogenic
impacts causing fo re st frag m en tatio n and affecting the n aviga bility o f bolongs in the mangrove
forests o f Sokone (Senegal). A geom atic study supporting the m anagem ent o f natural resources
(this issue).
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Wave m odeling Catalan coast: an intercom parison
Germ onpré M atthias1, Hana Ortega Y am om oto1, A gustín Sánchez-Arcilla2 and Jaak M onbaliu1
1 Hydraulics Laboratory, D epartm ent o f Civil Engineering, KU Leuven, Kasteel park Aren berg 40,
Postbus 2448, 3001 Heverlee, Belgium
E-mail: iaak.m onbaliu@ bw k.kuleuven.be
2 Laboratori d'Enginyeria Marítima, LIM/UPC, Barcelona, Spain
Wave m odeling is well established and forecasts have become very reliable. However detailed wave
m odeling in coastal areas is still very d iffic u lt. Land and local o ro grap hy affect the w ind fie ld s and
therefore affect local wave grow th. For waves approaching the shore the bottom effects become
im p o rta n t and may dom inate the local wave energy processes.
In the fram e w o rk o f the FP7 project FIELD_AC an intensive m easurem ent campaign was carried out
in fro n t o f the Catalan coast and several project partners used th e ir m odel set-up to hindcast the
wave conditions. The m odel results deviated considerably more than expected from the
m easurem ents and fro m each other.
In th is study, one wave m odel set-up is used to system atically investigate possible sources o f
differences. To th is end the d iffe re n t bathym etries, the d iffe re n t w ind field and the d iffe re n t
boundary co nd itio ns from the original intercom parison exercise are being used. Some firs t results
o f th is investigation w ill be shown.
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M odelling m ix o tro p h y in eu trophied coastal ecosystems
Ghyoot Caroline, Christiane Lancelot and Nathalie Gypens
Laboratoire d ’Ecologie des Systèmes Aquatiques (ESA)
Université Libre de Bruxelles (ULB), Campus Plaine CP221, Boulevard du Triom phe, 1050 Brussels,
Belgium
E-mail: cqhvoot@ ulb.ac.be
Human pressure has considerably altered the n u trie n t loads to estuarine and coastal systems,
increasing the q u a n tity and m odifying the sto ichiom e tric balance (N:P:Si) and chem ical form s
(orga nic/in orga n ic) o f n utrien ts available to phytoplankton. This cultural e utrophication has led to
harm ful algal bloom s in many coastal areas, often dom inated by m ix o tro p h ic species (Burkholder et
al., 2008). Such is the case in the ‘excess nitrate - low phosphate’ Southern Bight o f the North Sea
dom inated by Phaeocystis globosa. This haptophyte has been reported to use organic resource to
compensate fo r P deficiency (van Boekei and Veldhuis, 1990). Yet, little is known on mechanisms
allow ing th is s h ift fro m p ho totro ph to m ix o tro p h y and how th is affects food web interactions and
biogeochem ical cycles. As firs t step in th is direction we here present a m echanistic model o f
Phaeocystis globosa m etabolism th a t includes the up regulation o f alkaline phosphatase, an enzyme
th a t hydrolyses the dissolved organic phosphorus (DOP) to release phosphate. A fte r studying the
se nsibility o f the m odel to n u trie n t co nd itio ns and param eters co n tro llin g the hydrolysis o f DOP,
th is simple m odel w ill be integrated into e xisting MIRO model o f Lancelot e t al. (2005) and tested
fo r its capacity to describing d ia to m /Phaeocystis globosa and n u trie n t cycling in the Southern Bight
o f the North Sea. Further analysis o f m odel results w ill explore co nd itio ns fo r m ix o tro p h y
emergence and the effect on food web interactions.
References
Burkholder J.M., P.M. G libert and H.M. Skelton. 2008. M ixotrophy, a m ajor mode o f n u tritio n fo r
harm ful algal species in e utrop h ic waters. H arm ful Algae 8( 1):77-93.
van Boekei W.H.M. and M.J.W. Veldhuis. 1990. Regulation o f alkaline phosphatase synthesis in
Phaeocystis sp. Marine Ecology-progress Series 61:281-289.
Lancelot C., Y. Spitz, N. Gypens, K. Ruddick, S. Becquevort, V. Rousseau, G. Lacroix and G. Billen.
2005. M odelling diatom and Phaeocystis bloom s and n utrien t cycles in the Southern Bight o f
the North Sea: the MIRO model. Marine Ecology Progress Series 289:63-78.
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Investigating evolution o f closely related, sym patric cryptic species
using com plete m itoch on drial DNA
Grosemans Tara, Sofie Derycke and Tom Moens
Marine Biology section, Faculty o f Science, Biology D epartm ent, U niversity o f Ghent,
Krijgslaan 281 (S8), 9000 Gent, Belgium
E-mail: tara.qrosem ans@ uqent.be
C ryptic species are organism s w ith very sim ilar m orphology but d is tin c t genetic make-up. They can
be found in many animal groups, but typ ica lly in organism s fo r which chem ical recognition is more
im p o rta n t than visual recognition fo r m ating. If the cryptic species are living in sym patry (in the
same area), reproduction could, in theory, s till be possible and hence, gene flo w w ill occur. Gene
flo w w ill in h ib it fu rth e r d iffe re n tia tio n o f the species and thus spéciation. Why spéciation does or
does not occur, is not always clear and investigating the genes th a t are under selection w ill provide
more insights in the spéciation process.
Genetic differences can be detected by com paring the genom es o f the species. These genetic
differences can be as large as those observed in species w ith clear m orphological d istinctions. The
position o f the gene in the genome or alteration in the genes by m utation, are a few exam ples o f
these genetic differences. Four cryptic species o f the marine nem atode L itod itis m a rin a species
com plex are held in m onospecific cultures. Recent research found th a t these fo u r species cannot
interbreed, but th ey do co-occur. Therefore reproductive barriers m ust exist between the d iffe re n t
subspecies. N ext-generation sequencing allows to sequence com plete genomes instead o f a few
genes and enables to differen tia te between the nucleotides and the position o f the genes in the
genome. By com paring the m itochondrial genomes o f closely related species, we can investigate
which genes are under selection and which are im p o rta n t fo r the spéciation and evolution o f the
cryptic species.
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Towards a model fo r the re d is trib u tio n o f harbour porpoises
(Phocoena phocoena) due to pile driving in Belgian waters
H ae ltersjan , Valérie Dulière, Laurence Vigin and Steven Degraer
Royal Belgian Institute o f Natural Sciences (RBINS), O perational D irectorate Natural Environm ent, 3de
en 23ste Linieregim entsplein, 8400 Ostend and Gulledelle 100, 1 200 Brussels
E-mail: i.haelters@ mumm.ac.be
In 2011 the offshore wind farm at the T horntonbank, Belgian waters, entered its second phase, w ith
the piling o f 49 ja cke t fo un da tio ns fo r 48 wind tu rb ine s and an offshore high voltage substation. As
pile driving is known to generate high underw ater sound levels, it is im p o rta n t to assess its impacts
on cetaceans, which depend on the em ission and reception o f sound fo r fo ra gin g, spatial
o rien ta tion and social interactions. We investigated the effects on the harbour porpoise (Phocoena
phocoena), the m ost com m on cetacean in Belgian waters, by perform ing standardised visual aerial
line transect surveys before and during the piling phase. One week before piling started, harbour
porpoises were very com m on, w ith average densities o f more than 2 anim als.km 2. One week into
the piling phase changes in density and spatial d is trib u tio n clearly suggested harbour porpoise
displacem ent due to behavioural responses elicited by repeated, relatively short piling events.
We developed a m odel o f the expected re d istrib u tio n o f harbour porpoises a fte r disturbance due to
pile driving and applied it to data on harbour porpoise density d is trib u tio n p rior to the start o f
piling. Model results o f changes in density and d is trib u tio n showed good agreem ent w ith
observations. This approach should be considered a firs t step tow ards a fu tu re prediction o f the
effect o f piling on h arbour porpoises’ d is trib u tio n .
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Mangroves and livelihood - An assessment o f livelihood projects in
the mangrove ecosystems along the Kenyan coast
Hamza Am ina Juma1 2, James Kairo1, Nico Koedam2 and Farid Dahdouh-Guebas2 3
1 Kenya Marine and Fisheries Research Institute, PO Box 8 1651-80100, Mombasa, Kenya
E-mail: amina i2002@ vahoo.com
2 Laboratory o f Plant Biology and Nature Management, Faculty o f Sciences and Bio-engineering
Sciences, Vrije U niversiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
3 Laboratory o f Systems Ecology and Resource Management, D epartm ent o f Organism Biology,
Faculty o f Sciences, Université Libre de Bruxelles (ULB), Av. F.D. Roosevelt 50, B-1050 Brussels,
Belgium
The com bined pressure on fish e ry resources and critical habitats presents a challenge to co m m un ity
livelihood along the Kenyan coast. To co un ter declining fish ery and destruction o f habitats several
alternative livelihood activities have been initiated. These include ecotourism , m ariculture,
apiculture, and agro-forestry among others. The present study aimed at assessing the fe a s ib ility
and su stain ab ility o f ecotourism , m ariculture and beekeeping projects practiced in m angrove areas
in the Kenyan coast. Focus group discussions w ith project proponents, local interview s and online
Delphi survey w ith project stakeholders were conducted on projects fo un d in Mida and Majaoni in
the north; and Makongeni, Gazi and Wasini in the south coast o f Kenya. A to ta l o f 209 local people
were interviewed and 65% o f invited stakeholders responded fo r the Delphi survey. A SWOT analysis
identified the presence o f a healthy m angrove fo re st and su pp ort from local stakeholders as
projects strengths; and lack o f technical skills as a weakness o f the projects. D iversification o f the
livelihood projects was seen to be an o p p o rtu n ity; and illegal cu ttin g o f m angrove was found to be a
m ajor th re at to the projects. The study found sign ifican t differences in causes o f project failure in
the five sites. The study also established lack o f transparency and accountability, inadequate
m arketing, and lack o f co m m itm e nt among m em bers as some o f the factors co n trib u tin g to failure
o f these livelihood projects. This study provides recom m endations on how to im prove on efficiency
and effectiveness o f the initiatives so as to help in wise m anagem ent o f the mangrove ecosystem.
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Development o f efficient genetic markers to trace fish fraud and IUU
fishing
Hilleri Jasmien, Maria Coscia and Filip Volckaert
Laboratory o f Biodiversity and Evolutionary Genomics, KU Leuven,
Ch. D eberiotstraat 32, 3000 Leuven, Belgium
E-mail: iasm ien.hillen@ bio.kuleuven.be
Due to the increasing demand fo r fish, in com bination w ith chronic overfishing and IUU (illegal,
unreported and unregulated fishing), fish stocks are declining w orldw ide and food security is likely
to be hampered in the future. It is estim ated th a t g lobally a q u a rte r o f the catches are th ro u g h IUU
fishing. This leads to m ajor econom ic losses, underm ines sustainable fisheries and causes unfair
com petition. Nowadays the deficiencies in w ild fish are largely compensated th ro u g h aquaculture
production. However, the aquaculture ind ustry raises concerns about its environm ental
co m p atib ility. One o f the m ost pressing issues is the am ount o f escapees into the w ild and th e ir
subsequent m ixing w ith natural populations. Escapes not o nly impose large econom ic costs, they
also fo rm a th re at to local b io dive rsity th ro u g h com p etitio n and genetic p ollutio n. In addition,
despite the strict national and European regulations, there are increasing problem s w ith m islabeling
o ffis h (products). In th is project, we w ill use state-of-the-art Next Generation Sequencing (RAD-seq)
to develop SNP m arkers to unravel the fine scale population structure o f European sea bass
(D icentrarchus labrax) across its fu ll d is trib u tio n range - but w ith special atte ntio n fo r the North
East A tla n tic Ocean - and to d istin gu ish w ild fish from (escaped) aquaculture fish. Previous studies
have shown th a t th is approach guarantees the statistical power needed to successfully trace catches
back to th e ir farm (or population) o f origin. A fte r intensive validation and standardization
procedures, a diagnostic to o l based on a selected set o f h ighly d is c rim in a to ry SNP makers w ill be
developed. This to o l w ill be precise enough fo r forensic applications but at the same tim e cheap
and e fficie n t to be used as a routine co ntrol by fisheries a uth orities and in the food industry. The
generic m ethods developed here fo r sea bass w ill fa cilita te sim ilar fu tu re investigations on other
econom ic im p o rta n t marine fish.
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Analysis o f connectivity in the Skunk Clown Fish using a com bination
o f m icrosatellite and m itoch on drial genetic markers
Huyghe Filip and Mare Kochzius
Marine Biology, D epartm ent o f Biology, Vrije U niversiteit Brussel, Pleinlaan 2,
1050 Brussels, Belgium
E-mail: fhuvqhe@ vub.ac.be
Like m ost coral reef associated organism s, A m p h ip rio n akallopisos (Skunk Clown Fish), which lives
in m utualistic sym biosis w ith tw o species o f g ia nt sea anemones, is unable to m igrate fro m one
coral reef to another during its a du lt life stage. Dispersal between reefs in the patchy coral reef
environm ent is lim ited to an a pp ro xim a tely tw o-w eek long pelagic larval stage. Because small
pelagic larvae are extrem ely d iffic u lt to track in the open ocean, population genetics is a useful
technique to evaluate gene flo w and co nn ectivity between populations o f coral reef associated
organism s. Insight into connectivity between populations o f coral reef associated organism s is vital
fo r a correct spacing o f Marine Protected Areas, needed fo r the m anagem ent and conservation o f
coral reefs. A m p h ip rio n akallopisos has a d isju nct d is trib u tio n , occurring in the Western Indian
Ocean (WIO) and the Eastern Indian Ocean (EIO), separated by more than 4 ,50 0km o f open sea. This
study aims to estim ate levels o f gene flo w between these WIO and EIO populations and, on a sm aller
geographical scale, to reveal co nn ectivity between populations w ith in the WIO. A com bination o f
m itochondrial and nuclear genetic m arkers is used fo r th is approach. This, by providing inform ation
drawn from several parts o f the genome, reduces genetic sam pling error. But it also provides us
w ith the o p p o rtu n ity to compare data fro m a relatively slow evolving genetic m arker (Control Region
o f the m itochondrial DNA) w ith data from fast evolving m icrosatellite m arkers, revealing more
recent inform a tion on gene flow . Using a 337 base pair long sequence o f the C ontrol Region, a firs t
analysis was perform ed on 263 samples o f A. akallopisos individuals from 17 d iffe re n t sites in both
the WIO (Kenya, Tanzania, and Madagascar) and the EIO (Indonesia). Strong population structure
(cjost = 0.28; P < 0.001 ), and strong d iffe re n tia tio n (c£>ct = 0.61 ; P < 0.001 ) was encountered between
the EIO and the WIO populations, indicating very low gene flow . W ithin the WIO, low but significant
population structure (c£>st = 0.016; P < 0.01) was observed, but no clear genetic break could be
detected. Selective n eu tra lity tests (Tajim a’s D and Fu’s Fs) indicate a derogation fro m selective
neu tra lity in the WIO, and suggest th is population underw ent a rapid expansion in the past
(raggedness index r = 0.068; P = 0.82). D uring the com ing m onths, the dataset w ill be extended
w ith samples o f individuals fro m 5 to 10 d iffe re n t sites along the Mozambican coast, providing an
im proved geographic coverage fo r the WIO population. Furtherm ore, a to ta l o f 38 m icrosatellite
markers described in literature fo r species belonging to the genus A m phiprion are tested in
A. akallopisos.
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Preserving the archaeological heritage o f the North Sea using
innovative data acquisition techniques and webGIS
Incoul Annelies, Philippe De Maeyer, Bart De Wit, Alain De Wulf, Tine Missiaen, T im o th y Nuttens,
Cornelis Stal and Michiei Van den Berghe
D epartm ent o f Geography, Faculty o f Sciences, Ghent University, Krijgslaan 281 (S8),
B-9000 Gent, Belgium
E-mail: annelies.incoul@ uqent.be
The knowledge o f the underw ater cultural heritage in the Belgian North Sea is rather lim ited. Yet
th is subm erged heritage fo rm s an im p o rta n t aspect o f our cultural heritage and offers huge
possibilities fo r scientific and (inter-)cultural purposes. However th is unique underw ater archive is in
danger due to increasing econom ic activities at sea, such as aggregate extra ction , w ind farm s,
dredging, fish in g, etc. This is not the only threat. Due to the co m p le xity o f the state structure in
Belgium, a solid regulation regarding underw ater cultural heritage is still lacking, n otw ithstanding
the awareness o f the need to take resp on sibility fo r th is heritage in danger at the political and
adm inistrative level. The project SeArch offers solutions to these challenges via the developm ent o f
an e fficie n t assessment m ethodology and an approach tow ards a sustainable m anagem ent policy
and legal fram ew ork. This project involves a close collaboration between the fo llo w in g partners:
Flanders Marine Institute (VLIZ), Flemish Heritage Agency (FHA), Deltares (Departm ent o f Geology
and Geophysics) and Ghent U niversity (Renard Centre o f Marine Geology, M aritim e Institute and
D epartm ent o f Geography). The c o n trib u tio n o f the D epartm ent o f Geography is tw o fold . First, an
innovative survey m eth od o lo gy has to be created which allows accurate and co st-e fficien t evaluation
o f the archaeological potential in the inte rtid a l zones o f the Belgian beaches. Conventional
to po gra ph ic and bathym etric surface m odelling m ethodologies are not su fficie n t fo r these areas
and new surveying approaches are required. In the sum m er o f 2013, a field campaign was
conducted on the beach o f Raversijde (Belgium). A Mobile T errestrial Laser Scanning (MTLS)
config uratio n on an am phibious vehicle was used to detect archaeological relicts. Previous
fe a sib ility studies have dem onstrated th a t th is set-up is very prom ising fo r inte rtid a l surface
m odelling in com parison w ith o the r m easurem ent techniques. The c o nfig uratio n w ith an
am phibious vehicle also enables data acquisition w ith unsettled w eather and d iffic u lt terrain
co nditions in a reasonable tim e span and at a reasonable cost. Moreover, the technique appears to
close the spatial incom pleteness between land measurements and m easurem ents in shallow w ater
(with a depth o f less than ten meter). D igital Elevation Models (DEMs) are constructed from the
acquired spatial data. Secondly, the D epartm ent o f Geography is responsible fo r the set-up o f a
web-based Geographical Inform ation System/Service (webGIS) as part o f a new and specialized
Spatial Data Infrastructure (SDI). The application w ill allow e ffic ie n t integration and visualisation o f
archaeological and environm ental data in a user-friendly way. By im plem enting a webGIS, the
benefits o f standard map reading (such as providing insight) can be com bined w ith fa cilitie s such as
easy accessible spatial analysis and feature querying in an interactive environm ent accessible
w orldw ide. The p la tfo rm is useful fo r dissem ination o f inform a tion and fo r su pp ort o f decision
makers.
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Drowned but not deserted. Interactions between social and
ecological processes o f estuarine landscapes after flooding. T est­
case: the Waasland polders on the w est-bank o f the River Scheldt
(1 6 th -l 9th centuries)
Jongepier lason1, under supervision o f Tim Soens2 and Stijn Tem m erm an3
1 D epartm ent o f History, D epartm ent o f History, U niversity o f A ntw erp
Stadscampus, S.R-A.112, Rodestraat 14, 2000 Antw erpen, Belgium
E-mail: iason.ionqepier@ uantwerpen.be
2 D epartm ent o f History, U niversity o f A ntw erp
Stadscampus, S.D.31 3, Grote Kauwenberg, 18 2000 Antw erpen, Belgium
3 D epartm ent o f Biology, U niversity o f A ntw erp
Campus Drie Eiken, U niversiteitsplein 1, 2610 A ntw erpen, Belgium
This pitch presentation w ill be used to give an overview o f fo u r years o f doctoral research on the
post-m edieval interactions in the estuarine landscape o f the Waasland Scheldt polders.
Estuarine landscapes are very dynam ic ecosystems which makes it very d iffic u lt to m odel social and
ecological adaptations after catastrophic inundations. In th is research project the evolution o f tid al
channels a fte r historical inundations and the human re-occupation o f flooded areas in the late
medieval and early modern Western Scheldt Estuary are used to enhance o u r knowledge o f the lon g ­
term interactions between ecological and social processes.
In the period a fte r the late-16th century inundations both ecological and social (or socioeconom ical) processes to o k place, each interacting w ith one another. In th is presentation we w ill
discuss fo u r elem ents th a t shaped and interacted w ith in the study area fro m the late 16th to the
19th century: (1) the extensively mapped tid al channels which were responsible fo r heightening the
m arshlands to an ‘em bankable’ height, (2) the soil structure in later em bankm ents, determ ined by
the fo rm e r tid al marsh structure, (3) the em bankm ent process (m ainly induced by the Arenberg
fam ily) in which technical solutions had to be found in order to deal w ith com plications due to the
tid al marsh structure and (4) land use and land value in the em bankm ents (as results o f the above
m entioned processes).
1. A fte r the 16th century inundations an extensive tid al channel netw ork developed. This netw ork
allowed the tra n sp o rt o f sedim ents into the tid a l marsh, resulting in a natural heightening o f the
marshlands, which was a conditio sine qua non fo r later em bankm ents o f the tid al marsh, since at
least a m ajor part o f the marsh should be raised above mean high w ater level. Furtherm ore, the
tid al channel structure was extensively mapped since the fo rm e r imposed technical d iffic u ltie s
during fu tu re em bankm ents.
2. The second elem ent o f interaction is form ed by the soil (or sedim ent) co nd itio ns inside and
outside the em bankm ents. The outer dike area is form ed by tid al channels, m udflats and (higher)
tid al marsh. This th re e-p artition is reflected in the embanked areas (the fo rm e r tid al marsh) which
have a subdivision in sand, silt and clay. Therefore, q uantitative evidence fo r the correlation
between the (form er) tid al marsh structure and the soil structure w ithin the embanked marshes was
gathered using soil samples and grain size analysis.
3. In the th ird part we w ill focus on the human activity in the inundated area. Over a period o f three
centuries the extensive tid al marsh (drowned in 1 583-85) was gradually re-em banked under a
grow ing influence o f the Arenberg fam ily. These embankers had to handle the com plexities
imposed by the natural situation o f the tid al marsh.
4. Interaction o f the above m entioned elem ents created a typical soil structure in the d iffe re n t
em bankm ents, which resulted in d iffe re n t o p p o rtu n itie s fo r land use. Since the q u a lity o f the soils
has an influence on crop yields, th is pattern also translated in d iffe re n t land values w ithin the
em bankm ent. Q uantitative spatial m icro-level analysis was used to establish a proven correlation o f
these physical and socio-econom ical properties.
- 70 -
References
Allen J.R.L. 1 992. Large-scale te xtu ra l patterns and sedim entary processes on tid a l salt marshes in
the Severn Estuary, southw est Britain. Sedim entary Geology 8 1 :2 9 9 -3 1 8.
De Kraker A.M.J. 2007. De o ntw ikke lin g van het landschap. In: Wilssens, M. (Ed.) Singelberg: het
kasteel en het land van Beveren. Tielt, Lannoo.
Guns P. 2008. H istorische evolutie van het polderlandschap langs de linke r Scheldeoever.
Heruitgave editie 1973. Borgerhout, W aterbouw kundig Laboratorium .
Jongepier I., T. Soens and S; Tem m erm an. 2012. Poldercartografie. De rol van kaarten bij
bedijkingen en landschapstransform atie. In: Ooghe B., C. Goossens and Y. Segers,. (Eds) Van
brouck to t dyckagie. V ijf eeuwen Wase polders. Sint-Niklaas, Abim o.
Masure H., I. Jongepier, T. Soens, R. Vermoesen and E. Wauters,. 201 2. Landschaps- en
bew oningsevolutie van de O ud-Arenbergpolder, 17e-19e eeuw. T ijd -sch rift. Heemkunde en
loka al-erfg oe dp raktijk in Vlaanderen 2:34-49.
Mijs M. 1 973. De landschapsgeschiedenis van de scheldepolders ten noorden van Antw erpen:
bijdrage to t de historische geografie van de scheldepolders. Belgische vereniging voor
aardrijkskundige studies 42:39-1 24.
Priester P.R. 1 998. Geschiedenis van de Zeeuwse landbouw circa 1600-1 910. W ageningen,
Landbouw universiteit.
Soens T., P. De Graef, H. Masure ,and I. Jongepier. 2012. Boerenrepubliek in een h eerlijk landschap?
Een nieuwe kijk op de Wase polders ais landschap en bestuur. In: Ooghe B., C. Goossens and Y.
Segers (Eds). Van brouck to t dyckagie. V ijf eeuwen Wase polders. Sint-Niklaas, Abim o.
Tem m erm an S., G. Govers, P. Meire and S. Wartel. 2003. M odelling long-term tid a l marsh grow th
under changing tid a l co nd itio ns and suspended sedim ent concentrations, Scheldt estuary,
Belgium. Marine Geology 193:151-169.
Van C ruyningen P. 2000. Behoudend maar buigzaam : boeren in West-Zeeuws-Vlaanderen, 16501 850. W ageningen, U niversiteit van W ageningen, A fdeling Agrarische Geschiedenis.
Van C ruyningen P. 2006. Profits and risks in drainage projects in Staats-Vlaanderen, c. 1590-1665.
Jaarboek voor Ecologische Geschiedenis 2 0 0 5 /2 0 0 6 : 1 23-142.
Van Gerven R. 1 977. De Scheldepolders van de Linkeroever (Land van Waas en Land van Beveren):
bijdrage to t de geschiedenis van natuur, land, volk. Beveren.
W olters M.J. 1869. Recueil de lois, arrêtés, règlem ents etc., concernant l'a dm inistratio n des eaux et
polders de la Flandre orientale. Gent, Hoste.
W oodroffe C.D. 2003. Coasts: Form, Process and Evolution. C am bridge, C am bridge U niversity Press.
- 71 -
Genetic evidence confirm s polygam ous m ating system in a
crustacean parasite w ith m ultiple hosts
Jossart Q u en tin 12, Rémi A. W attier2, Chedly Kastally13, Serge A ro n 3, Bruno David2, Chantai De Ridder'
and T hie rry Rigaud2
1 Laboratoire de Biologie Marine (CP 160/15), Université Libre de Bruxelles (ULB)
50 avenue F. Roosevelt, 1050 Brussels, Belgium
E-mail: aiossart@ ulb.ac.be
2 Biogéosciences, UMRCNRS 6282, Université de Bourgogne, 6 boulevard Gabriel
21000 Dijon, France
3 Behavioral and Evolutionary Ecology (CP 160/1 2), Université Libre de Bruxelles (ULB)
50 avenue F. Roosevelt, 1050 Brussels, Belgium
Mating systems are diverse in animals, notably in crustaceans, but can be inferred fro m a lim ited
set o f parameters. Baeza and Thiel (2007) proposed a m odel p redicting m ating systems o f
sym biotic crustaceans w ith three host characteristics and the risk o f predation. These authors
proposed five m ating systems, ranging fro m m onogam y to polygynandry (where m ultiple m ating
occurs fo r both genders). Using m icrosatellite loci, we tested the putatively m ating system o f the
ectoparasite crab Dissodactylus p rim itiv u s . We determ ined the m ating frequencies o f males and
females, parentage assignm ent (COLONY & GERUD software) as well as the contents o f female
spermathecae. Our results are g lo ba lly consistent w ith the m odel o f Baeza and Thiel and showed,
to g e th e r w ith previous aquarium experim ents, th a t th is ectoparasite evolved a polygam ous m ating
system where males and females move between hosts fo r mate search. Parentage analyses revealed
th a t polyandry is freq ue n t and concerns more than 60% o f clutches, w ith clutches being fe rtiliz e d by
up to 6 d iffe re n t fathers. Polygyny is supported by the detection o f e ig h t males having sired tw o
d iffe re n t broods. We also detected a sig n ifica n t p aternity skew in 92% o f the m ultipaternal broods.
Moreover, th is skew is probably higher than the estim ation from the brood because additional
alleles were detected in m ost o f spermathecae. This high skew could be explained by several factors
as sperm co m p etitio n or cryptic female choice. Our genetic data, com bined w ith previous anatom ic
analyses, provide consistent argum ents to suggest sperm precedence in D. p rim itivu s.
References
BaezaJ.A. and M. Thiel. 2007. The m ating system o f sym biotic crustaceans: a conceptual model
based on o p tim a lity and ecological constraints. In: DuffyJ.E. and M. Thiel (Eds). Evolutionary
ecology o f social and sexual systems. Crustaceans as m odel organism s. O xford, England:
O xford U niversity Press, p .249-267.
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Steps towards the use o f the compactness index to detect
perforation and frag m e nta tion in mangrove forests
Kemalasari Delia', Arim atéa de Carvalho Ximenes' 2, Farid D ahdouh-G uebas'2and Nico Koedam'
' Laboratory o f Plant Biology and Nature Management, Vrije U niversiteit Brussel - VUB, Pleinlaan 2,
B-1050 Brussels, Belgium
E-mail: dkemalas@vub.ac.be
2 Laboratory o f Systems Ecology and Resource Management, Université Libre de Bruxelles - ULB,
Av. F.D. Roosevelt 50, B-1050 Brussels, Belgium
Mangroves are forests th a t grow in the intertida l zone o f coastal areas and estuaries in the tropics
and warm subtropics, w ith extensive roots well adapted to the saline w ater and a n o x ic /h y p o x ic
soils. These h ighly productive forests can provide many ecosystem services, including carbon
sequestration, coastal protection to wave action, storm surges, tsunam is, sea-level rise, a b u ffe r to
sedim entation loads, am ongst others (Donato e t al., 2011 ; Dahdouh-Guebas e t al., 2005; Di N itto et
a i, 2008; Rajkaran and Adams, 2010). Mangroves consist o f rem arkably few species, and as
ecosystems they are g lo ba lly threatened as the rate o f its deforestation is comparable to th a t o f the
te rre stria l rainforests (Polidoro e t a i, 2010; FAO, 2007; Duke et a i, 2007). If effective conservation
does not take place at im p o rta n t locations, the w o rld ’s m angrove fo rm a tion s w ould disappear in the
next 100 years (Duke e t a i, 2007). C urrently, man-induced habitat frag m en tatio n is a concern, a
process th ro ug h which contiguous fo re st stretches are broken down into several patches (Bogaert et
a i, 2011). Each patch being more exposed to edge effects, th is degrades the overall ecological
q u a lity o f the forests (Ries e t a i, 2004). The landscape tran sfo rm atio n process th a t leads to habitat
fragm entation is often preceded by perforation, which is m arked by a d is tin c t spatial pattern
(Forman, 2001). Perforated forests w ill have more edge effects by the presence o f inner holes,
leading to fu rth e r fo re st degradation. The m ethodology to q u a n tify the process o f fo re st
fragm entation and perforation using landscape m etrics has been w idely applied in te rre stria l
ecosystems. However it is still understudied in m angrove ecosystems and com plicated because o f
th e ir naturally patchy pattern. A fte r a m ethodological analysis related to scale effects o f in p u t data,
we assess the m agnitude, the e xte n t and the location o f perforated m angrove forests using
Compactness Index on a 30-m eter resolution global m angrove d is trib u tio n map published by Giri et
a i (2011). Here the em phasis lies on mangroves o f the United States, Kenya, Sri Lanka and South
Africa. The Compactness Index, which ranges fro m 0 to 1, measures the com pactness o f forests,
w ith low values indicating perforated shapes and high values fo r com pact shapes (M ontero and
Bribiesca, 2009). We fo un d th a t th is index detected highly porous patterns in the mangroves along
the Sine Saloum delta in Senegal and the mangroves along the Gambia River, am ongst many other
locations in the w orld. We also found th a t th is index is consistently detecting perforated patterns in
the mangroves along the river.Therefore, th is index is considered to be quite sensitive to measure
the degree o f perforation, if one considers the range o f values obtained, to be fu rth e r applied in
diachronic analysis o f fo re st fragm entation. We also indicated the scaling relation o f th is index on
the mangroves o f the United States, Kenya, Sri Lanka and South Africa, using 6 d iffe re n t scales (30,
60, 120, 240, 480, and 960 meter) and th is index shows a consistent relation tow ard the coarser
scales. Further study on m ultiscale analysis is needed to characterise the scaling relation o f this
index, so th a t conservation action can be directed at precise locations.
References
Bogaert J., Y.S.S. Barima, J.Ji, H. Jiang, I. Bamba, L.I.W. Mongo, A. Marna, E. Nyssen, F. DahdouhGuebas and N. Koedam. 2011. A m ethodological fram e w o rk to q u a n tify anthropogenic effects
on landscape patterns, p. 141-167. In: Hong S.-K e t a i (Eds). Landscape Ecology in Asian
Cultures, Ecol. Res. Monog.
Dahdouh-Guebas F., L.P. Jayatissa, D. Di N itto, J.O. Bosire, D. Lo Seen and N. Koedam. 2005. How
effective were mangroves as a defence against the recent tsunam i? Curr. Biol. 1 5(1 2):443-447.
Di N itto D., F. Dahdouh-Guebas, J.G. Kairo, H. Decleir, N. Koedam. 2008. D igital terrain m odelling to
investigate the effects o f sea level rise on mangrove propagule establishm ent. Mar. Ecol. Prog.
Ser. 3 56 :1 7 5 -1 8 8 .
Donato, D.C., J.B. Kauffman, D. M urdiyarso, S. Kurnianto, M. Stidham and M. Kanninen. 2011.
Mangroves among the m ost carbon-rich forests in the tropics. Nature Geoscience 4:293-297.
Duke N.C., J.O. Meynecke, S. D ittm ann, A.M. Ellison, K. Anger, U. Berger, S. Cannicci, K. Diele, K.C.
Ewel, C.D. Field, N. Koedam, S.Y. Lee, C. Marchand, I. Nordhaus and F. Dahdouh-Guebas. 2007.
A w orld w ith o u t mangroves? Science 31 7:41-43.
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FAO 2007. The w orld's mangroves 1 980-2005. FAO Forestry Paper 1 53. Rome: FAO Forest
Resources Division.
Forman R.J. 2001. Land mosaics: The ecology o f landscapes and regions. C am bridge U niversity
Press, UK.
Giri C., E. Ochieng, L.L. Tieszen, Z. Zhu, A. Singh, T. Loveland, J. Masek and N. Duke. 2011. Status
and d istrib u tio n o f m angrove forests o f the w orld using earth observation satellite data. Glob.
Ecol. Biogeogr. 20:1 54-1 59.
M ontero R. and E. Bribiesca. 2009. State o f the art o f com pactness and circu la rity measures. Int.
Math. For.4(27):l 305-1 335.
Polidoro B.A., K.E. Carpenter, L. Collins, N.C. Duke, A.M. Ellison, J.C. Ellison, E.J. Farnsworth, E.S.
Fernando, K. Kathiresan, N.E. Koedam, S.R. Livingstone, T. Miyagi, G.E. Moore, V.N. Nam, J.E.
Ong, J.H. Primavera, S.G. Salmo III, J.C. Sanciangco, S. Sukardjo, Y. Wang and J.W.H. Yong. 2010.
The loss o f species: m angrove e xtin ctio n risk and geographic areas o f global concern. Plos ONE
5(4).
Rajkaran A. and J.B. Adams. 2010. The im plications o f harvesting on the population structure and
sedim ent characteristics o f the mangroves at Mngazana Estuary, Eastern Cape, South Africa.
Wetl. Ecol. Manag. 18:79-89.
Ries L., R.J. Fletcher, J. Battin and T.D. Sisk. 2004. Ecological responses to habitat edges:
mechanisms, models, and va ria b ility explained. Annu. Rev. Ecol. Evol. Syst. 35:491 -522.
- 74-
Sedimentation in response to sea level rise in mangroves o f Mwache
Creek, Mombasa-Kenya: a f ie ld and m odeling study
Kimeli A m o n 1, Charles M agori1, Jared Bosire2, Nico Koedam3 and Stijn Tem m em an4
1 Kenya Marine & Fisheries Research Institute, PO Box 81651-80100, Mombasa, Kenya
E-Mail: akim eli@ km fri.co.ke
2 W orld W ildlife Fund (WWF), PO Box 6 2440-00200, Nairobi, Kenya
3 D epartm ent o f Biology, Vrije U niversiteit Brussels, Pleinlaan 2, B-1050 Brussels, Belgium
4 D epartm ent o f Biology, U niversity o f Antw erpen, U niversiteitsplein 1, B-2610 Antw erpen, Belgium
The sta b ility o f m angrove ecosystem in the face o f rising sea level highly depends on th e ir a b ility to
m aintain th e ir surface elevations relative to sea level. This a b ility is a fu nctio n o f m ineral and
organic sedim entation and com paction rates. In Kenya, there is little inform a tion regarding the
m agnitude and interaction o f the above biophysical processes th a t cum ulatively co n tro l accretion
and elevation changes. This study carried o ut a field study in Mwache Creek, Kenya to exam ine the
prevailing rates o f accretion and elevation changes. Variation in accretion rates, suspended
sedim ent concentrations (SSC) and elevation changes were measured in the densely and less
vegetated parts o f Mwache Creek. Suspended sedim ent concentrations varied between 0 .0 7 6 g /L in
less vegetated site to 0 .1 2 8 g /L in the densely vegetated site. Elevation change rates (m m y r1)
measured using sedim entation-erosion tables (SETs) varied between 1 .3 3 m m y r' in the less
vegetated to 2 .4 8 m m yr' in the densely vegetated sites and th is correlated to average accretion
rates measured by the sedim ent traps ranging between 0 .6 m m y r' in the less vegetated to
1.0 5 m m yr' in the densely vegetated sites. There was a positive correlation between accretion rates
and suspended sedim ent concentrations (R2 = 0.60). The sea level in Mombasa was fo un d to be
rising at a rate o f 3.1 m m y r1 which correlates well w ith projected global rates o f 3 .0 m m y r'. The
model sim ulations showed th a t the grow th o f m angrove surface elevation is influenced by
mangrove surface elevation (which controls inundation), m ineral sedim entation, com paction rates
and am ount o f sedim ents in suspension (assist in accretion) but rates o f organic sedim entation and
low settling velocities caused m inim al effect. This study showed th a t biophysical processes in such
ecosystems interact and th e ir m agnitudes moderate the accretion and elevation changes.
Q uantification o f these biophysical processes provides an understanding o f the in te g rity and
su stain ab ility o f m angrove ecosystems in the face o f global threats including relative sea level rise.
K e yw o rd s: Mangroves; Suspended sedim ent concentration; Accretion; Sea level rise; M odeling.
- 75 -
A n th ro p o g e n ic impacts causing forest fra g m e n ta tio n and affecting
the navigability o f bolongs in the mangrove forests o f Sokone
(Senegal). A geom atic study sup p o rtin g the m anagem ent o f natural
resources
Kungula Makoso D jedje1, Sylvestre Géoris', Katrien Q u isth o u d t1 and Farid Dahdouh-Guebas123
1 Laboratory o f Systems Ecology and Resource Management, Université Libre de Bruxelles - ULB,
Avenue Franklin D. Roosevelt 50, CPI 2 6 4 /1 , B-1050 Brussels, Belgium
E-mail: dkunqula@ ulb.ac.be
2 Laboratory o f Plant Biology and Nature Management. Vrije U niversiteit Brussel - VUB, Pleinlaan 2,
B-1050 Brussels, Belgium
3 This study was in part financed by the Zemst-Sokone city link.
Sokone's mangrove lies in the natural region o f Sine-Saloum in Senegal. It is a delta form ed by tw o
rivers branched into a m ultitu de o f creeks (bolongs) subject to the influence o f the sea and tides
(Lhomme, 1978). Economic activities o f the region: artisanal fisheries, tra n s p o rt and trade o f
mangrove products (wood, oyster, shells,...) depend on m angrove and naviga bility o f bolongs which
is related to the state o f the mangrove. Mangroves in th is region are subject to both natural and
anthropogenic pressures th a t cause degradation. Logging is the main anthropogenic cause o f this
degradation. Wood requirem ents are expected to increase due to population grow th and d e ficit o f
means o f co ntrol and m anagem ent o f natural resources (Géoris e t a i, 2014, th is issue).
This study is based on a com bination o f remote sensing and field w ork to id e n tify and examine
more or less disturbed areas caused by logging and sedim entation o f bolongs responsible fo r the
fragm entation, in ord er to conclude if th is m angrove resists to natural and anthropogenic influences
w ith respect to its structure and dynamics.
Mangrove areas as well as points o f sedim ented bolongs were identified on a visual basis o f Google
Earth images, field visits and a survey o f the population. In to ta l 36 quadrats o f 100m 2 each along a
land-water transect have been made. A t each quadrat we recorded tree identity, stem diam eter,
d istrib u tio n o f adult, young and juvenile trees, tree height, salinity, num ber o f cut stems, the X-Y
coordinates o f each a du lt tree and GPS coordinates.
A Detrended Correspondence Analysis (DCA) was applied to inte rp re t the d is trib u tio n o f tree
species in adult, young and juve nile in term s o f present and fu tu re vegetation dynamics while the
species-environm ent relationship was established th ro u g h the canonical correspondence analysis
(CCA). Past dynamics w ill be partly expressed th ro ug h the frequency d is trib u tio n o f diam eter
classes at 2.5cm intervals (Dahdouh-Guebas e t a i, 2002). The CCA results w ill be used to
understand the im pact o f logging on the vegetation structure observed and hence the
anthropogenic impact.
Land cover maps were drawn from Landsat TM 1988 and ETM+ 2007 images and a to po gra ph ic
map at a scale o f 1:50,000 to view the recent occupation o f mangrove and non mangrove.
Sedimented bolongs sectors w ill be related to perim eters o f disturbed vegetation th ro u g h the map
to determ ine if th ey match.
Results may h ig h lig h t a relationship between fo re st fragm entation due to logging and
sedim entation o f bolongs. W herever possible, we w ill id e n tify areas o f urgent conservation and
provide guidelines fo r the restoration a n d /o r e x p lo ita tio n o f o the r areas.
References
Dahdouh-Guebas F. and N. Koedam. 2002. A synthesis o f e xiste n t and potential m angrove
vegetation structure dynamics from Kenyan, Sri Lankan and Mauritanian case-studies. Bull.
Séanc. Acad. Sei. Outre-M er 48 (20 02 -4 ):4 8 7 -5 11.
Dahdouh-Guebas F.,J.G. Kairo, L.P. Jayatissa, S. Cannicci and N. Koedam. 2002. An o rd in a tion study
to view vegetation structure dynamics in disturbed and undisturbed m angrove fo re st in Kenya
and Sri Lanka. Plant Ecology 161(1): 123-135.
Géoris S., D. Kungula Makoso and F. Dahdouh-Guebas. 2014. Are the mangroves o f Sokone (Sine
Saloum, Senegal) utilize d in a sustainable way ? An analysis m erging socio-ecologic interviews
w ith vegetation science (this issue).
Lhomme F. 1978. Sénégal, Sine-Saloum, Gambie, Casamance: H ydrographie, pêche crevettière.
Centre de recherches océanographique de Dakar-Thiaroye. ISRA. Archive 66. 29p.
T om linson P.B. 1 986. The botany o f mangroves. Cam bridge (UK):Cambridge U niversity Press.
- 76 -
Ecosystem Models as Support to Eutrophication Management in the
North A tla ntic Ocean (EMoSEM)
Lacroix G.1, X. D esm it1, V. D ulière', N. Gypens2, C. Lancelot2, G. Billen3, J. G arnier3, V. T hie u 3,
M. Silvestre3, P. Passy 3, L. Lassaletta 3, G. G u itta rd 3, S. T héry 3, A. Ménesguen 4, B. T h o u v e n in 4,
M. Dussauze3, M. Mateus 6, R. Neves 6, J. S o brinh o 6, I. Ascione Kenov 6, C. Garcia6, H. Lenhart7,
H. Los8, T. T r o o s t8 and J. Vander M olen9
1 O perational D irectorate Natural Environm ent (OD Nature), Royal Belgian Institute o f Natural
Sciences (RBINS), Gulledelle 100, 1200 Brussels, Belgium
E-mail: G.Lacroix@ mumm.ac.be
2 Ecologie des systèmes aquatiques (ESA), Université Libre de Bruxelles (ULB), Campus de la Plaine,
CP221, Boulevard du triom phe, 1050 Bruxelles, Belgium
3 UMR Sisyphe, UPMC/CNRS, 4 Place Jussieu, 75005 Paris,
France
4 D épartem ent Dynamiques de l'Environnem ent C ôtier (DYNECO),Laboratoire Ecologie Benthique
IFREMER/Centre de Brest, B.P. 70, 29280 Plouzané, France
3 ACTIMAR, 36, quai de la Douane, F 29200 Brest, France
6 In stitu to do Mar (IMAR), In stitu to Superior Técnico (1ST), D epartam ento de Engenharia
Lisbon, Portugal
Mecánica,
7 Research Group Scientific C om puting, U niversität Ham burg, Bundesstraße 45a, D-20146 Hamburg
8 Deltares, PO Box 177, NL-2600 MH Delft, the Netherlands
9 CEFAS, Low estoft Laboratory, Low estoft NR 33 0HT, United Kingdom
A m ajor challenge in EU marine governance is to reach the good environm ental status (GES) in the
north-eastern A tla n tic (NEA). Existing approaches do not integrate the eutrop h ica tion process in
space (continuum river-ocean) and in tim e (past, present and fu tu re status). A strong need remains
fo r (i) kn o w le d g e /id e n tifica tio n o f all the processes th a t co ntrol e utrophication and its
consequences, (ii) consistent and harm onized reference levels assigned to each e utrophicationrelated indicator, (iii) ide ntifica tion o f the main rivers d ire c tly or ind ire ctly responsible fo r
eutrophication nuisances in specific areas, (iv) an integrated tran sbo u nd ary approach and (v)
realistic and scientific-based n utrien t reduction scenarios. The SEAS-ERA project EMoSEM
(h ttp ://w w w 2 .m u m m .a c .b e /e m o s e m /) aims to develop and com bine the state-of-the-art m odelling
to ols describing the river-ocean continuum in the NEA continental seas w ith the objective to: (i)
suggest innovative ecological indicators to account fo r HABs in the GES d e fin itio n , (ii) estim ate the
needs to reach GES in all marine areas (distance-to-target requirem ent, DTTR), (iii) id e n tify ‘ rea listic’
scenarios o f n u trie n t reduction in the river watersheds o f NEA and (iv) assess the im pact o f the
‘ rea listic’ scenarios in the sea, and compare to DTTR. Marine ecological models w ill be used to track
the nutrients in the sea, and trace back th e ir riverine or oceanic sources w ith the transboundary
n utrien t tra n sp o rt m ethod (TBNT). TBNT application is a prerequisite fo r DTTR estimates. A generic
watershed m odel applied to NEA rivers w ill calculate te rre s tria l n u trie n t e xports to the sea under
d iffe re n t scenarios: (i) A past ‘ p ristin e -lik e ’ scenario, where natural n u trie n t exports are estim ated in
the absence o f human influence and (ii) a series o f fu tu re ‘ rea listic’ scenarios, where d iffe re n t
w astewater treatm ents and agricu ltu ra l practices are com bined. EMoSEM w ill deliver coupled rivercoastal-sea m athem atical m odels and w ill provide guidance to end-users (policy- and decision
makers) fo r assessing and com bating e utrophication problem s in the NEA continental waters.
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The Com pendium fo r Coast and Sea
Lescrauwaet A nn-K atrien', Hans Pirlet1, Thom as Verleye', Jan Mees' and Rudy Herm an2
1 Flanders Marine Institute (VLIZ), InnovOcean site, W andelaarkaai 7, 8400 Oostende, Belgium
E-mail: com pendium @ vliz.be
2 D epartm ent o f Economy, Science and Innovation (EWI), Koning A lb e rt ll-laan 35, PO Box 10,
1030 Brussels, Belgium
The C om pendium fo r Coast and Sea is an integrated knowledge docum ent about the socio­
economic, environm ental and in stitu tio n a l aspects o f the Coast and Sea in Flanders and Belgium.
The docum ent aggregates disperse inform a tion and data fro m Flemish and Belgian marine and
m aritim e research. The integrated and m u ltid is c ip lin a ry character o f the C om pendium aims to
increase the com m unication w ith in the netw ork o f marine experts and intends to enhance the
v is ib ility and accessibility o f marine research. In th is regard, the C om pendium fits in w ith the
European aspirations fo r a sustainable and Integrated M aritim e Policy and Integrated Coastal Zone
Management.
The knowledge docum ent consists of:
■ An overview o f the marine scientific landscape in Flanders/Belgium (Chapter 1)
■ A sum m ary o f the knowledge on d iffe re n t user fu nctio ns o f the coast and sea (Chapter 2)
■ A non-exhaustive overview o f relevant regulations and policy instrum ents and an elaboration on
the marine science-policy interface (Chapter 3).
The C om pendium fo r Coast and Sea is an initiative o f the Flanders Marine Institute (VLIZ) in
collaboration w ith a group o f experts consisting o f scientists, policym akers, civil society
organisations, etc.
The ta rg et audience o f the C om pendium fo r Coast and Sea are scientists, the broad group o f
experts who are actively and professionally involved w ith the coast and sea - at an international,
European, national, regional and local level - as well as representatives from business and drivers o f
innovation.
The docum ent is published in English and Dutch, and w ill be updated w ith a fixe d frequency. The
C om pendium can also be consulted online on: w w w.com pendium coastandsea.be.
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Insights on the link between surface p ro d u c tiv ity and benthic
com m u nities in the deep sea
Lins Lidia12, Katja G u ilin i1, Freija H auquier1, M. André Esteves2 and Ann Vanreusel1
1 Marine Biology Departm ent, Ghent University, Krijgslaan 2 8 1 /s8 9000, Belgium
E-mail: lidia.linspereira@ uqent.be
2 Laboratorio de Meiofauna, Universidade Federal de Pernambuco, Av. p ro f Moraes Rego, 1235
CEP 50670-901, Brazil
The biological pum p, looked as the fraction o f prim ary production exported from the euphotic
zone, is considered an im p o rta n t m echanism responsible fo r the coupling between the prim ary
p ro d u ctivity carried o ut in surface waters and the sea bottom , the so-called benthic-pelagic coupling
(De La Rocha and Passow, 2007). These e xp o rt flu xes reflect general patterns o f prim ary
production, reaching the seabed and acting as food sources fo r benthic organism s, such as the
small benthic-dw elling metazoans named m eiofauna (Lutz e ta !., 2002; Ramirez-Llodra et a i, 2010).
Samples fo r th is study were collected in the deep sea Southern Ocean, along the Polar Front, and
differed in an increasing east-west surface-based ch lorophyll a (Chia) gradient. Surface and benthic
environm ental param eters were measured, as well as the particulate organic carbon (POC) flu x
th ro ug h alg orith m s based on satellite m easurements. In addition, th e ir link w ith m eiofauna to ta l
and relative abundances and standing stocks was analysed. The results revealed an east-west
increase in net prim ary p ro d u ctivity (NPP) and b ottom Chia concentration (p<0.001), w hile the POC
flu x d ive rg e ntly decreased westwards (p<0.001) and showed an inverse relationship w ith depth,
revealing th a t a lower am ount o f the net prim ary p ro d u c tiv ity reaches deeper regions. Nematodes
were the m ost abundant group in the m eiofauna (84.4% - 92.4%) and its relative abundances
increased westwards, being m ainly correlated w ith the NPP and the Chia. C oncerning the nematode
standing stocks, no clear patterns in relation to the d iffe re n t surface and benthic variables was
observed. The inverse correlation between m eiofauna abundance and POC flu x m ig h t be due to
differences in depth (3760.5m -41 54.2m), which plays a crucial role in the tra n sfe r efficiency o f POC
or because the processes influencing POC fluxes are not q u a ntita tive ly understood, despite being
well studied. Moreover, POC flu xes estim ates are based in a m odel (Lutz e t a i, 2002) w ith an equalarea grid o f 9-km resolution and m ig ht not reflect small-scale patterns. Furtherm ore, considering
the influence o f strong currents in the Southern Ocean, lateral advection processes may be driven
and move waters w ith a high Chia concentration eastwards (Dem ivov e t a i, 2012). Nevertheless,
based on the positive correlation between m eiofauna and Chia and NPP m onthly-averaged values we
can assume th a t more productive regions su pp ort higher m eiofauna and nem atode abundances.
References
De La Rocha C.L. and U. Passow. 2007. Factors influencing the sinking o f POC and the efficiency o f
the biological carbon pum p. Deep-Sea Research Part ll-Topical Studies in O ceanography 54(57):639-658.
Dem idov A.B., S.A. M osharov et al. 2012. M eridional asym m etric d is trib u tio n o f the prim ary
production in the A tla n tic Sector o f the Southern Ocean in the austral spring and summer.
Oceanology 52(5):623-634.
Lutz M., R. Dunbar et al. 2002. Regional va ria b ility in the vertical flu x o f particulate organic carbon
in the ocean interior. Global Biogeochemical Cycles 16(3).
Ramirez-Llodra E., A. Brandt et al. 2010. Deep, diverse and d e fin ite ly d iffe re n t: unique a ttrib utes o f
the w orld's largest ecosystem. Biogeosciences 7 (9 ):2 8 5 1-2899.
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Corsican seagrass detritus: an o p po rtune shelter or a copepod
Eldorado?
Mascart T h ib a u d 12, Gilles Lepoint2, François Remy2, Sylvie G obert2, Patrick Dauby3
and Marleen De T ro ch 1
1 Marine Biology, Ghent University, Krijgslaan 2 8 1 -S8, B-9000 Gent, Belgium
E-mail: T h ib a u d .Mascart@UGent.be
2 MARE Centre, Laboratory o f Oceanology, U niversity o f Liège, Allée de la Chimie 1 7-B6c,
B-4000 Liège, Belgium
3 MARE Centre, Laboratory o f Systematic and Anim al Diversity, U niversity o f Liège, Allée de la
Chimie 17-B6c, B-4000 Liège, Belgium
Seagrass ecosystems are extensive beds o f marine flo w e rin g plants bordering tro p ica l and
tem perate coastal regions. They play an im p orta nt role in m aintaining biological p ro d u c tiv ity and
bio-geochem ical cycles in the sea and su pp ort higher d ive rsity and abundance o f fauna in
com parison to adjacent non-vegetated areas. The seagrass meadow p rim ary production can be
d irectly consumed th ro ug h herbivory but the m a jo rity o f the plant m aterial falls on the sea flo o r
during the autum nal leaf senescence. The leaf litte r then degrades w ith in the meadow or
accum ulates w ith o the r micro- and m acrophytodetritus to fo rm d e tritu s accum ulations on the
adjacent non-vegetated sand patches. These exported accum ulations are quite dynam ic in relation
to seafloor g eom orphology and local hydrodynam ics. Thus, the d etritus accum ulations are an easily
disturbed ephem eral environm ent w ith one large in flu x a year. C onsequently the physico-chem ical
characteristics can change very fast and im pact the sheltering capacity and food supply present.
Nonetheless, fishes, m acrofauna and m eiofauna are om nipresent th ro u g h o u t the year.
In our study site along the shore o f N.-W. Corsica, Posidonia oceanica seagrass meadows are
characterised by substantial d e tritu s accum ulations. The present study aimed to analyse the
b io dive rsity o f the copepod species com m unities (Crustacea, Copepoda) in those detritus
accum ulations. The results showed th a t the copepod d etritus co m m un ity consisted o f a m ixture o f
species th a t are also found in adjacent habitats (seagrass meadow, sedim ent, e p ilith ic habitats,
w ater column). Each adjacent habitat is characterised by organism s th a t are m orphologically
adapted to the specific features o f th a t habitat. The m a jo rity o f copepods are epiphytic (order
Harpacticoida), th a t occur typ ically on seagrass leaves and macroalgae. O ther species are planktonic
(orders C yclopoida and Calanoida) and some were benthic (order Harpacticoida), known from the
nearby sedim ent. A m in o rity o f the copepod co m m un ity were parasitic on fish or invertebrate (order
Siphonostom atoida).
In ord er to clarify th e ir origin, we assume th a t passive tra n s p o rt by currents plays a sign ifican t role
next to the active m igration fro m the anoxic sedim ents under the detritus. For sure they also
reproduce w ithin the d e tritu s packages as we fo un d many nauplii, copepodites and gravid females.
The above-m entioned suggestions cannot explain such high density o f copepods by themselves.
O ther attraction mechanisms are needed to explain the im p o rta n t am ount o f planktonic and
epiphytic species w ith good sw im m ing ability, such as higher food accessibility. In the d e tritu s no
plant-defence mechanisms are present anym ore and a lot o f m icro-organism s and thus potential
food sources are present. Furtherm ore, the dense d e tritu s package provides shelter and protection
from potential predators.
Subsequently we may consider the d e tritu s accum ulations as a copepod species-specific opportune
Eldorado fo r sheltering, nursing and feeding.
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The early nitrogen starvation response o f the diatom Phaeodactylum
tric o rn u tu m
M atthijs M ic h ie i'23, Michele Fabris123, T. Obata4, Stefaan Broos36, Gino B a art'23, A.R. Fernie4,
Wim Vyverm an3 and Alain G oossens'2
' D epartm ent o f Plant Systems Biology, VIB, T echnologiepark 927, B-9052 Ghent, Belgium
E-mail: m im at@ psb.vib-uqent.be
2 D epartm ent o f Plant Biotechnology and Genetics, Ghent University, T echnologiepark 927,
B-9052 Ghent, Belgium
3 D epartm ent o f Biology, Ghent University, Krijgslaan 281, B-9000 Ghent, Belgium
4 Max Planck Institute o f M olecular Plant Physiology, W issenschaftspark Golm,
Am M ühlenberg 1, D-14476 Potsdam-Golm, Germany
3 D epartm ent fo r M olecular Biomedical Research, VIB, T echnologiepark 927, B-9052 Ghent, Belgium
6 D epartm ent o f Biomedical M olecular Biology, Ghent University, B-9052 Ghent, Belgium
In th is study we investigated the tra n scrip to m ic and m etabolic response o f Phaeodactylum
tric o rn u tu m to nitrogen starvation and o th e r stresses during the firs t 24 hours. P. tric o rn u tu m is a
unicellular marine alga o f the coastal zone. These algae live in a varied environm ent where n utrien t
and lig h t availab ility can fluctuate substantially. N itrogen starvation induces the accum ulation o f
lipids in algae which has potential biotechnological purposes. The aim o f the study was to find
tran scrip tion al regulators th a t coordinate th is process.
Using RNA-seq, we sequenced a to ta l o fte n points across the d iffe re n t tim e p o in ts and conditions.
The response in the prim ary m etabolism was found to be dram atically d iffe re n t when com pared to
nitrogen starvation in green algae. The c itric acid cycle especially was under tig h t tran scrip tion al
co ntrol and likely plays a central role in the repurposing o f carbon and nitrogen in the cell. To
investigate th is fu rth e r m etabolic labeling experim ents are being perform ed.
A d ditio na lly, in the p rom otors o f genes upregulated during nitrogen starvation several
overrepresented m otifs were found. By em ploying a Yeast One Hybrid screen, a pote ntia lly novel
tran scrip tio n fa cto r term ed NMB1 was found. NMB1 was previously unannotated but appears
evolutionary conserved in the heterokontae. P. tric o rn u tu m contains tw o o the r m em bers o f this
gene fam ily. The expression profiles o f tw o o ut o f three putative tra n scrip tio n factors cluster
to g e th e r w ith a substantial part o f the nitrogen salvaging and am ino acid breakdown genes,
im plying a fu n ctio n a l link w ith the ta rg et process. NMB1 would be the firs t tra n scrip tio n factor
known to be involved in n u trie n t responses in diatom s.
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Building a digital Zooplankton sample library as part o f the LifeWatch
marine observatory
M ortelm ans Jonas, Lennert Tyberghein, Klaas Deneudt and Francisco Hernandez
Flanders Marine Institute (VLIZ)
InnovOcean site, W andelaarkaai 7, 8400 Oostende, Belgium
E-mail: ionas.m ortelm ans@ vliz.be
Z ooplankton is u biquitous in the marine environm ent and concentrations o f the d iffe re n t
Zooplankton species are used to determ ine the ecologie q u a lity o f these w ater bodies. Furtherm ore,
as these organism s are at the base o f the food chain, serving as food fo r higher tro p h ic levels,
Zooplankton is a crucial com ponent o f the marine ecosystem o f the North Sea.
As part o f the marine observatory fo r LifeWatch, VLIZ is building a sample library o f d ig ita l
Zooplankton images. Whereas tra d itio n a l m ethods to study Zooplankton are intensive and d iffic u lt
to autom ate, the processing o f Z ooplankton samples w ith a Zooscan is a quick, straightforw ard
m ethod th a t gives a clear insig ht in the ta xon om ic assemblage o f a Zooplankton sample. In
addition, the data is collected and processed in a cheap, low risk and controlled environm ent.
With the ZooScan, high resolution d ig ita l images o f preserved Zooplankton samples are taken in a
sem i-autom ated way. Specific software (Plankton Identifier) can calculate several param eters on
each particle in yo ur sample. A fte r creating a learning set fo r the d ig itize d particles (e.g. m anually
assign ta xon om ic ranks to some specimens), the software is capable to assign specimens to high
ta xon om ic level (e.g. Calanus, Apendicularia, Gammaridae, Cumacea, Isopoda,...). This m ethod
provides exact counts and size calculations o f individuals on each ta xon om ic level. The
visualization and count o f m icro-debris (e.g. plastics, fibres) is also possible. Long tim e series on
Zooplankton can yield inform a tion on ecosystem va riability, or provide indication o f anthropogenic
changes, etc.
LifeWatch supports b io dive rsity and ecosystem research by building an infrastructure th a t allows
researchers to com m unicate, share data, analyse results, create models, manage projects and
organise train in g . A ll collected samples, both o rigin al and d ig ita l, are accessible to the scientific
com m unity.
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JPI Oceans’ p ilo t actions
Muñiz PinieIla Ángel E.1, John Hanus2, W endy Bonne12and W illem De M oor12
1 Flanders Marine Institute (VLIZ)
InnovOcean site, Wandelaarkaai 7, B-8400 Oostende, Belgium
E-mail: anqel.m uniz.piniella@ vliz.be
2 JPI Oceans Secretariat
Rue du Trône 130, 1050 Brussels, Belgium
The JPI Oceans p ilo t actions are (small-scale) activities, lim ited in tim e and scope, designed to test
o ut new modes o f cooperation. They should o ffe r a fit fo r purpose co n trib u tio n to address societal
needs and challenges related to marine and m aritim e issues. In a dd ition, th ey are im plem ented to
dem onstrate the added value o f JPI Oceans as a high-level intergovernm ental strategy process.
C urrently there are three p ilo t actions in the pipeline, however th e ir fin al scope and content still
needs to be agreed upon:
Ecological aspects of micro-plastics in the marine environment
The accum ulation o f plastic litte r in the environm ent has become a grow ing concern ever since the
rise in plastics production. The p ilo t action w ill specifically com prise (i) analytical m ethod
developm ent; (ii) an in terla b orato ry study, and (iii) research into the ecotoxicological effects o f
particles. Part one w ill focus on the developm ent o f m ethods fo r the e xtraction, analysis and
reporting fo r selected m atrices (sedim ent, biota and w ater column). The action aims to improve
current m ethods both in term s o f th e ir robustness and cost-effectiveness, and seeks to harmonise
research m ethodologies to enable better data com parisons. In a next phase the p ilo t action plans to
focus on an inte rla b o ra to ry study on m icro-plastics in sedim ent in ord er to validate m ethods and
standard operation protocols. The th ird part w ill focus on the study o f the e cotoxicological effects
o f plastic particles, particula rly on the mechanisms o f to x ic im pact on organism s, the im pact o f
chronic exposure as well as the tra n sfe r o f m icro-plastics into the (human) food chain and the
resulting effects.
Ecological aspects of deep-sea mining
Marine m ineral resources, such as polym etallic nodules, crusts and subm arine-exhalative sulfides
have recently become the ta rg et o f policy makers, m ining com panies and deep sea researchers.
However, com m ercial deep-sea m ining w ill always cause a m ajor im pact on local ecosystems. This
p ilo t action aims to assess the long-term environm ental consequences o f deep-sea m ining,
especially human im pact on the benthic com m unity. Germ any offered 90 days fo r on-site research
on RV Sonne fo r a cruise in the Pacific in early 201 5. Envisaged is a three-legged cruise to visit the
DISCOL area o ff the coast o f Peru where a sea-floor disturbance expe rim en t was carried out in the
1980s as well as to conduct research in the various (undisturbed) claims o f European countries in
the C larion-C lipperton Fracture Zone in the Pacific Ocean. The p ilo t action w ill enable scientists to
better assess the im pact o f deep sea m ining activities and, ultim ately, to make recom m endations
fo r environm ental standards to allow policy makers to define a better legal fram e w o rk fo r deep sea
m ining activities.
M ulti-use of Infrastructure for Monitoring
A long h istory o f m on itoring o f the marine environm ent in the North Sea exists, including
oceanographic, hydrographic, biological and human im pact m on itoring program s. To make best use
o f each Euro spent, international and inter-d iscip lin a ry collaboration is needed to coordinate the
North Sea m on itoring activities, crossing national borders. The p ilo t action on M ulti-use o f
Infrastructure picks a num ber o f indicators th a t require m o n itoring activities (for exam ple marine
litte r on the sea flo o r from survey catches, consum ption by fish th ro ug h stomach sam pling,
bio dive rsity o f infauna from benthos boxcore sampling), try in g to integrate them w ith current (fish
stock) m on itoring program s. The intention is to develop p ilo t studies to test these on current
m on itoring activities as soon as possible.
- 83 -
UHPLC-HR-Orbitrap mass spe ctrom etry fo r quantitative analysis o f
lip o ph ilic marine to x in s in shellfish
Orellana G abriel12, Julie Vanden Bussche', Lieven Van M eulebroek1, M ichiei Vandegehuchte2,
Colin R. Janssen2 and Lynn Vanhaecke1
1 Laboratory o f Chemical Analysis, Faculty o f V eterinary Medicine, Ghent University,
Salisburylaan 133, B-9820 Merelbeke, Belgium
E-mail: Gabriel.Qrellana@UGent.be
2 Laboratory o f Environm ental T o xico lo g y and A quatic Ecology, Faculty o f Bioscience engineering,
Ghent University, Jozef Plateaustraat 22, B-9000 Ghent, Belgium
Up to now, analytical m ethods used fo r the detection o f marine to x in s have generally been
focussing on the analysis o f 13 lip o p h ilic to xins. However, to date more than 200 lip o p h ilic marine
to xin s have been described (Gerssen e t al., 2011). Edible shellfish can bioaccum ulate marine to xin s
when grazing on to x ic marine m icroorganism s, particula rly marine microalgae such as certain
species o f dinoflagellates and diatom s, creating a potential food safety risk to humans. D uring the
last years, many analytical m ethods based on liquid chrom atography coupled to tandem mass
spectrom etry (LC-MS/MS) have been consolidated by inter-la bo ra to ry validations. However, the main
drawback o f LC-MS/MS m ethods remains the lim ited num ber o f com pounds th a t can be analysed in
a single run. Moreover, due to the targeted nature o f LC-MS/MS only known to x in s fo r which
m ethods have been previously o ptim ize d w ill be detected. Therefore in th is study, a m ethod based
on ultra high-perform ance liquid chrom atography (UHPLC) coupled to high resolution (HR) O rbitrap
mass spectrom etry was developed and its quantitative perform ance evaluated fo r co nfirm a to ry
analysis o f regulated lip o p h ilic m arine to x in s in shellfish flesh (M ytilus edulis, C rassostrea gigas,
C erastoderm a edule, and Ensis ensis) according to Com m ission Decision 2 00 2/6 5 7/E C (CD) and EU
Reference Laboratory fo r Marine Biotoxins SOP 2011. Okadaic acid (OA), dinophysistoxin-1 (DTX-1),
pectenotoxin-2 (PTX-2), azaspiracid-1 (AZA-1), yessotoxin (YTX) and 13-desm ethyl spirolide C (SPX1) were q uantified using m atrix-m atched calibration curves. The obtained results fo r recovery,
repeatability, w ith in -la b o ra to ry re p ro d u c ib ility (RSDr), decision lim it , line arity and ruggedness were
co m p lia nt w ith CD recom m endations. The linearity was evaluated by preparing 8 -p oin t calibration
curves in m atrix and correlation coefficients (R2) obtained fo r each com pound were > 0.99. For all
com pounds the RSDr ranged fro m 2.9% to 4.9%, repeatability from 2.9% to 4.8% and recovery from
90% to 112% fo r three spiked levels. In a dd ition, a firs t co n firm a to ry ide ntifica tion o f the
com pounds was perform ed by detecting the [M+H]+ or [M-H] ion w ith th e ir specific retention tim es
and accuracies. Secondly, the nC /l2C diagnostic isotopic ratio was selected fo r co nfirm a tion o f a
co m p ou nd ’s identity. In conclusion, UHPLC-HR-Orbitrap MS allowed a more accurate and faster (less
than 4m in.) detection o f the ta rg et to x in s than previously described LC-MS/MS m ethods.
Furtherm ore, HRMS allows to retrospectively screen fo r many to x in analogues and m etabolites
using its fu ll scan capabilities but also untargeted screening th ro u g h the use o f m etabolom ics
software.
References
Gerssen A., P.P.J. M ulder And J. De Boer. 2011. Screening o f lip o p h ilic marine to x in s in shellfish and
algae: Developm ent o f a library using liquid ch rom atography coupled to O rbitrap mass
spectrom etry. Analytica Chim ica Acta 685:176-185.
- 84-
Linking the densities o f fish fun ction al groups and developm ental
stages to benthic structure
Osuka Kennedy1 2, M elita Samoilys2, David O bura2, Mare Kochzius1 and Ann Vanreusel3
1 Vrije U niversiteit Brussels, Plaine 2, 1050 Brussels
E-mail: Kennedv.Osuka.Edeve@vub.ac.be or kennvlardv5@ vahoo.com
2 CORDIO East A frica # 9 Kibaki Flats, Kenyatta Beach, Bamburi Beach PO Box 10135 Mombasa
80101, Kenya
3 Marine Biology Section, D epartm ent o f Biology, U niversity o f Gent, Ledeganckstraat 35, B-9000
Gent, Belgium
Identification o f habitats o f sim ilar characteristic is a steppingstone tow ards determ ining
managem ent measures needed to sustain and protect fish stocks. The process plays a crucial part
in designation o f zones m eriting marine protection and restoration. In th is regard studies using
habitat structure to describe regional d is trib u tio n o f fish co m m un ity have revealed substantial
spatial co m p le xity in fish densities (Pitman e t al., 2007). This study builds on th is e xplora tory
habitat approach, in which broad scale coral reef m u lti-h a b ita t types w ill be identified and a link to
associated fish com m unities undertaken. The study purposes to use benthic and fish survey
datasets collected th ro ug h underw ater visual census (UVC) across fo u r geographical countries
w ith in the western Indian Ocean biogeographic province. The benthic dataset consisted o f
percentage cover o f hard corals, soft corals, fle shy algae, tu r f algae and rubble while fish dataset
consisted o f fish densities and size classes o f species representing 12 tro p h ic fu n ctio n a l groups.
C lassification o f surveyed sites based on th e ir m inim um and m axim um depths, w ill provide a
platform to assess the spatial d is trib u tio n o f fish fu nctio na l groups in shallow, deep and whole
range depth zones. Flomogenous reef habitat types w ill be ascertained in a p rio r i using the
sim ila rity profile routine (SIMPROF) in hierarchical cluster analyses (Clarke et al., 2008) and a
linkage to the densities o ffis h fu n ctio n a l groups evaluated thereafter. C om parison o f species size
classes to size o f m a tu rity m etrics available in FishBase w ill enable resolving o f developm ental
stages (adult and juve nile) o f the censured fish, and th e ir d is trib u tio n w ithin the identified reef
habitat types assessed while m aking inferences to potential causal factors. Prelim inary results o f the
benthic cover shows five sta tistically sim ilar clusters; three dom inated by fleshy algae, tu r f algae
and hard corals and tw o having m ixed habitat types. Linking o ffis h densities to habitat types is on
going.
References
Clarke K.R., P.J. Som erfield and R.N. Gorley. 2008. Testing o f null hypotheses in e xplo ra to ry
co m m un ity analyses: sim ila rity profiles and biota-environm ent linkage. Journal o f Experimental
Marine Biology and Ecology 366(1 ):56-69.
Pittman S..J., C. Caldow, S.D. Hile and M.E. Monaco. 2007. Using seascape types to explain the
spatial patterns o ffis h in the mangroves o f SW Puerto Rico. Marine Ecology Progress Series
348:273-284.
- 85 -
Looking fo r mangroves: detection o f the n o rth e rn m o st West-African
mangroves in a non-m angrove dom inated landscape using remote
sensing
Otero Viviana1, Katrien Q u isth o u d t2, Nico Koedam' and Farid D ahdouh-G uebas'2
' Laboratory o f Plant Biology and Nature Management, Mangrove Management Group, Faculty o f
Science, Vrije U niversiteit Brussel (VUB), Pleinlaan 2, B-1050 Brussels, Belgium
E-mail: voterofa@ vub.ac.be
2 Laboratory o f Systems Ecology and Resource Management, Faculté des Sciences, Université Libre
de Bruxelles (ULB), Avenue F.D. Roosevelt 50, B-1050 Brussels, Belgium
Detection o f m angrove forests in the Parc National du Banc d ’A rg uin (PNBA), M auritania, in two
satellite images is the overall objective o f th is study. These forests have an extrem ely discontinuous
d istrib u tio n and are o nly com posed o f Avicennia g erm inans (L.) Stearn. The mangroves do not
provide a direct social or econom ic benefit fo r the fisherm en villages located in the PNBA (DahdouhGuebas & Koedam, 2001). Nevertheless, m angroves provide breeding, spawning, hatching and
nursing areas fo r fish and shellfish, maintenance o f biodiversity, coastal protection, and aesthetic
value (Walters e t al., 2008). Furtherm ore, the mangroves o f the PNBA are interesting because o f
th e ir biogeographical characteristics. They are the n orthe rnm ost mangroves in West A frica and are
able to survive in a very dry environm ent (Dahdouh-Guebas and Koedam, 2001; Blasco, 2010). The
m angrove forests o f the PNBA have a poor regeneration rate and there are records o f a more
extended m angrove area 4,000 to 5,000 years ago (Mahé, 1985; Gowthorpe, 1993; DahdouhGuebas and Koedam, 2001). Remote sensing is a technique used to detect, describe, q u a n tify and
m o n ito r changes o f land cover and land-use patterns in spatial and tem poral dim ensions (DahdouhGuebas, 2002; Dahdouh-Guebas and Koedam, 2008). This study analyses tw o satellite images from
Cap T im iris area in the National Park. One image was captured in 2004 w ith the QuickBird Sensor
and the second image was captured in 2011 w ith the GeoEye-1 Sensor. The image o f 2004 has a
spatial resolution o f 61cm in the panchrom atic layer and 2.4m in the m ultispectral layers. The
image o f 2011 has a spatial resolution o f 41cm in the panchrom atic layer and 1.65m in the
m ultispectral layers. The detection o f mangroves in th is area is challenging because the reflectance
o f the surrounding land cover - silt, clay and desert soils, herbaceous te rre stria l vegetation, and
seagrass - confuses the detection process. In particular, th is ongoing study w ill: (i) v e rify w hether
given the current technical and local characteristics it is possible to detect mangroves
u nam biguously and (ii) id e n tify the more useful approaches to detect mangroves according to the
current characteristics. Both pixel-based and object-based classifications w ill be explored, the
fo rm e r being based on spectral inform a tion only, the latter on a com bination o f spectral and shape
features. The classifications w ill be evaluated by means o f an e rro r m atrix analysis.
References
Blasco F. 2010. A b o u t the mangroves o f Banc d ’A rguin, M auritania. ISME/GLOMIS Electronic Journal
8:13 - 15.
Dahdouh-Guebas F. 2002. The use o f remote sensing and GIS in the sustainable managem ent o f
trop ical coastal ecosystems. Environm ent, Developm ent and Sustainability 4:93 -112.
Dahdouh-Guebas F. and N. Koedam. 2001. Are the n orthe rnm ost mangroves o f W est-Africa viable?
A case study in Banc d ’A rguin National Park, M auritania. H ydrobiologia 458:241 - 253.
Dahdouh-Guebas F. and N. Koedam. 2008. Long-term retrospection on mangrove developm ent
using tran sdiscip lin ary approaches: A review. A quatic Botany 89:80 - 92.
Gowthorpe P. 1993. Une visite au Parc National du Banc d ’A rguin. Itinéraires - Présentation des
principales com posantes naturelles. Parc National du Banc d ’A rg uin, N ouakchott, M auritania:
193pp.
Mahé E. 1985. C o n trib u tio n à l’étude scientifique de la région du Banc d ’A rguin. Peuplements
avifaunistiques. PhD thesis. Université de Science et Technique du Languedoc, France: 576pp.
Walters B.B., P. Rönnbäck, J.M. Kovacs, B. Crona, S.A. Hussain, R. Badola, J.H. Primavera, E. Barbier,
and F. Dahdouh-Guebas. 2008. Ethnobiology, socio-econom ics and managem ent o f mangrove
forest: a review. A quatic Botany 89:220 - 236.
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Building an ecologic-econom ic model to improve silvicultural
m anagem ent practices in Matang (Malaysia)
Quispe Zuniga Melissa R.1, Behara Satyanarayana2, Cyril Piou3, Uta Berger4, Hussain M ohd-Lokm an2,
Ibrahim Sulong2 and Farid Dahdouh-Guebas56
1 Vrije U niversiteit Brussel -VUB, Pleinlaan 2, B-1050 Brussels, Belgium
E-mail: m elissa.auispe.zuniqa@ vub.ac.be
2 Institute o f O ceanography and Environment-INOS, H igher In stitu tio n Centre o f Excellence (HICoE)
in Marine Sciences, U niversiti Malaysia Terengganu-UMT, 21030 Kuala Terengganu, Terengganu
Daru Iman, Malaysia.
3 CIRAD, UPR Bioagresseurs : Analyse et Matrîse du Risque, M ontpellier F-34398, France
4 Institute o f Forest Growth and Forest C om puter Sciences, TU Dresden, PO Box 111 7, 01735
Tharandt, Germany
5 Laboratory o f Systems Ecology and Resource Management, D epartm ent o f Organism Biology,
Faculty o f Sciences, Université de Bruxelles-ULB, Campus de la Plaine, Boulevard du Triom phe,
B-1050 Brussels, Belgium
6 Laboratory o f Plant Biology and Nature Management, Mangrove Management Group, Faculty o f
Sciences and Bio-engineering Sciences, Vrije U niversiteit Brussel-VUB, Pleinlaan 2, B-150 Brussels,
Belgium
Mangrove ecosystems are present in tropical coastlines and provide goods, services and econom ic
o pp o rtu n itie s fo r local com m unities (Barbier e t a i, 2011). Local people can use m angrove forests
fo r tim b e r and fuelw ood, animals fo r consum ption {e.g. fish, crabs) and services {e.g. nursery
grounds, breeding and feeding sites, and coastline protection) th a t m angrove forests provide
(Barbier e t a i, 2011). An excellent exam ple o f m anagem ent o f a mangrove fo re st is Matang
Mangrove Forest Reserve (in Malaysia) th a t has been managed since 1908 by Perak Forestry
D epartm ent fo r the production o f poles and fuelw ood (Chong, 2006). The need o f a m odel that
includes socio-econom ic aspects as well as fo re st grow th in Matang is im p o rta n t fo r shaping future
decisions, ensuring sustainable income sources fo r local people, and im proving the silvicultural
m anagem ent practices (Fontalvo-Herazo e t a i, 2011). The studies related to th is reserve have
focused on ecological or econom ic aspects; however, cu rren tly there is no research th a t has
considered the econom ic aspects in close relation to ecologie aspects. Therefore, the aim o f this
m aster thesis is to build an ecologic-econom ic m odel th a t includes labor cost fo r d iffe re n t
silviculture related activities, wood prices o f d iffe re n t qualities, benefits and costs o f
n a tu ra l/silvicu ltu ra l stands, and possibly hidden environm ental benefits, and th a t can predict future
su stain ab ility o f wood production under d iffe re n t scenarios o f ecologie or human impact.
This on-going study is divided in three parts; the firs t part is the developm ent o f an individualbased m odel in NetLogo v5.0.4. program , using ODD (Overview, Design concepts and Details)
Protocol (Railsback and Grimm , 2012) fo r the purpose o f m aking predictions, which are based on
the co nd itio ns th a t are influenced by potential econom ic factors th a t can influence m angrove fo re st
density. The second part consists o f a fie ld -co m po ne nt th a t w ill take place in February (2014), in
Matang Mangrove Forest Reserve (Perak, Malaysia); th is part consists o f an econom ic survey
involving the people who are part o f the m angrove wood trade. For th is reason the econom ic survey
is divided in fo u r groups: consumers, harvesters, wholesalers, and fo rm a l actors (related to Forestry
Departm ent). The th ird part w ill consist o f the calibration o f the developed m odel w ith the results o f
the econom ic survey and the ecological results (forest density in Matang Mangrove Forest Reserve)
th a t were made by Goessens (2011 ) in Matang.
Finally, we hope th a t the ecologic-econom ic m odel w ill enable us to determ ine the possible fa m ily
incomes in dependence o f changes in mangrove fo re st grow th and econom ic circum stances. The
predictions can be used to im prove current and fu tu re m anagem ent practices durin g the decision
m aking, p rotecting mangrove ecosystems and the livelihood o f local people w ho depend on the
mangrove forest.
References
Barbier E.B., S.D. Hacker, C. Kennedy, E.W. Koch, A.C. Stier and B.R. Silliman. 2011. The value o f
estuarine and coastal ecosystem services. Ecological M onographs 81 (2): 169-1 93.
- 87 -
Chong V.C. 2006. Sustainable u tiliza tio n and m anagem ent o f Mangrove ecosystems o f Malaysia.
A quatic Ecosystem Health & Management 9(2):249-260.
Fontalvo-Herazo M.L., C. Piou, J. Vogt, U. Saint-Paul and U. Berger. 2011. Sim ulating harvesting
scenarios tow ards the sustainable use o f m angrove fo re st plantations. W etlands Ecology and
Management 19(5): B97-407.
Goessens A. 2011. Floral d ive rsity and d is trib u tio n in the mangroves t Matang, West Peninsular
Malaysia, a fte r a century o f sustainable management. Master Thesis. Université Libre de
Bruxelles, 1 22pp.
Railsback S.F. and V. Grimm . 2012. Agent-based and individual-based m odeling: a practical
intro du ction . Princeton U niversity Press, 329pp.
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Limited clim atic niche fillin g o f mangroves
Q uisthoudt Katrien12, Loïc Pellissier3, Farid D ahdouh-G uebas'2, Nico Koedam2
and C hristophe F. Randin4
1 Laboratory o f Systems Ecology and Resource Management, Université Libre de Bruxelles
Av. F. D. Roosevelt, 50, B-1050, Brussels, Belgium
e-mail: kauistho@ ulb.ac.be
2 Laboratory o f Plant Biology and Nature Management, Vrije U niversiteit Brussel
Pleinlaan, 2, B-1050 Brussels, Belgium
3 A rctic Research Centre, D epartm ent o f Bioscience, Aarhus University, Aarhus, Denmark
4 Institute o f Botany, U niversität Basel, Schönbeinstrasse 6, 4056 Basel, Switzerland
An expansion o f the d istrib u tio n o f mangroves tow ards higher latitudes m ig ht be expected as a
consequence o f global w arm ing. However, mangroves may not yet have reached an e q u ilib riu m w ith
the current clim ate because o f Quaternary clim ate oscillations. This lack o f e q u ilib riu m may lim it
the a b ility to forecast mangrove range dynamics. In th is study, we exam ined the d is trib u tio n o f
mangroves w orldw ide to determ ine w hether and where mangrove species have reached the
potential latitud in al lim its dictated by clim ate.
We predicted the current d istrib u tio n o f the w o rld ’s 39 d om in a nt m angrove tree species based on
an ensemble o f species d istrib u tio n models (SDMs). The projected and observed latitud in al lim its o f
the mangrove fo re st and o f each species were com pared to id e n tify p otential areas w ith lim ited
clim atic niche fillin g (i.e. geographic areas where m angrove species are absent despite the
occurrence o f a p ote ntia lly suitable climate according to the SDMs).
Most mangrove species are not com pletely in e q u ilib riu m w ith cu rren t clim ate conditions. However,
where there is a continuous coastline fro m the southern to the northern latitud in al lim it (e.g. EastAfrica) more species have reached th e ir potential clim atic latitud in al lim its com pared to regions that
are composed o f scattered islands (e.g. South-East Asia). Hence, the greater prevalence o f lim ited
clim atic niche fillin g in the latter may be a ttrib u te d to dispersal tim e lag and the changes in the
config uratio n o f islands
Our study indicates a discrepancy between clim ate s u ita b ility and the accessibility o f sites by
mangrove species during colonisation. This fin d in g also suggests th a t lim ited m igrations by
mangrove species w ill occur in certain regions in a fu tu re w arm ing clim ate.
- 89-
Big bro the r is watching you! An acoustic receiver netw ork to track
the whereabouts o f fishes
Reubens Jan13, Ans M outon2, Klaas D eneudt3, Francisco Hernandez3 and André C attrijsse3
1 Marine Biology Research Group, Biology Departm ent, Ghent University, Krijgslaan 281, S8,
B-9000 Gent, Belgium
E-mail: lan.Reubens@UGent.be
2 Research Institute fo r Nature and Forest, K liniekstraat 25, B-1070 Brussel, Belgium
3 Flanders Marine Institute, InnovOcean site, Wandelaarkaai 7, B-8400 Oostende, Belgium
Camera surveillance, Bluetooth connection, social m edia... There are plenty o f possibilities to check
the w hereabouts o f people. But w hat w ith the whereabouts o f m igrating fishes? W o uldn’t it be
interesting to know th e ir whereabouts!
Since the 1900s, several West-European m ig rato ry fish populations suffered a substantial decline
and by 1950 many species were severely threatened or even e xtinct. Various causes fo r th is trend
have been reported, such as chem ical p ollutio n, changes in physical habitat, m igration barriers,
predation pressure (overfishing), lower body co nd itio n, infections, hydrodynam ic and climate
change. To help w ith the recovery and sustainable use o f the m ig rato ry fish species, several legal
incentives have been im plem ented d urin g the last decades.
However, crucial knowledge on the m igration routes, spatio-tem poral habitat use and behaviour o f
the m ig rato ry fish species is still lacking in many cases. This situation may change d rastically w ith
the developm ent and o ptim isa tio n o f new survey techniques. The m ost prom ising technique,
acoustic telem etry, allows fle xib le and co st-e fficien t spatio-tem poral tracking o f m ig ra to ry fish
species. VLIZ and INBO recently initiated a perm anent acoustic receiver netw ork in the Western
Scheldt Estuary and the Belgian coastal area in the fram e w o rk o f the LifeWatch project
(h ttp ://w w w .life w a tc h .b e ). This offers wide o p p o rtu n itie s fo r collaboration between Belgian partners
to study m ig ra to ry fish species w ith d is tin c t behaviour and habitat use at a larger (Belgian and
international) scale.
In ord er to cover the various modes o f m igration patterns, several m ig ra to ry fish species w ill be
studied. For m arine, coastal and estuarine systems, A tla n tic cod (Cadus m orhu a L.), w ill be the
m odel species, while In Belgian rivers European eel (A nguilla a n g u illa L.) is representative fo r
catadrom ous dow nstream m igration. In a later phase, o th e r species, such as European sea bass
(D icentrarchus la b ra x L.), tw aite shad (Alosa fa lla x L.), river lam prey (Lam petra flu v ia tilis L.) and sea
tro u t (Salmo tr u tta L.) can be added to the network.
The acoustic tracking w ill help to define
m igration behaviour.
m igration
- 90 -
routes, spatio-tem poral habitat use and
Parental feeding behaviour, m ercury accum ulation and o ffs p rin g
fitness: a p re lim ina ry study in the Lesser black-backed guii (Larus
fuscus)
Santos Cátia12, Marta M onteiro2, Susana Loureiro2, Davy Bosman', Tom Larsen1,
Liesbeth de Neve1and Luc Lens'
1 T errestrial Ecology Unit (TEREC), U niversity o f Ghent, Ghent, Belgium
E-mail: catiasofia.andradedossantos@ uqent.be or catiasantos@ ua.pt
2 D epartm ent o f Biology and CESAM, U niversity o f Aveiro, Aveiro, Portugal
A cquiring and allocating n u tritio n a l resources to survival and reproduction are key a ttrib u te s o f life history variation o f organism s, nonetheless a main fitness cost associated w ith resource acquisition
is exposure to environm ental contam inants (Stearns, 1992; Fry, 1995). The lesser black-backed guii
is a cosm opolitan seabird species particula rly known by its o p p o rtu n is tic feeding behaviour, and to
display a high individual variation in foraging e x p lo ita tio n o f marine and te rre stria l food webs,
which may interact w ith contam ination burdens accum ulated th ro u g h the year.
The overall aim o f th is prelim inary study was to assess how feeding behaviour o f parents could
interact w ith m ercury burdens accum ulated and be transferred to o ffsp rin g during the breeding
season. Mercury has been reported to bio m a g nify on marine food webs, causing a varied range o f
to xic effects on a du lt birds, fro m reduced reproductive success (e.g. reduced egg hatchability) to
neurological dysfunctions (Sundlof e t al., 1994; Gochfeld e t a i, 2002; Hoffm an e t a i, 2003),
nonetheless few studies have addressed the effect o f m ercury accum ulation on o ffsp rin g fitness.
In ord er to address th is topic, between 2012 and 2013, eggs and feathers (prim aries and chick
down feathers) as well as breeding data (e.g. clutch size, chicks developm ent, chick survival,
am ongst others) were collected in a long term study population o f ia r u s fuscus in Zeebrugge
(Belgium, 5 1 °2 ’ N, 0 3 °1 1 ’E). The tip s o f the firs t and tenth prim aries o f 26 breeding fem ales were
used to determ ine pro po rtio n o f marine and te rre stria l habitats e x p lo ita tio n during breeding and
w inte rin g seasons, while the tip s o f the second and ninth feathers were used to determ ine m ercury
burdens by atom ic absorption spectrom etry (ASS) w ith therm al decom position. A d ditio na lly,
m ercury burden in egg yolks, down feathers and prim aries o f chicks (collected ju s t p rio r to chick
fle dg in g) were as well analysed using the same principle.
Data obtained enabled us to d istin gu ish d iffe re n t female feeding strategies, from exclusive marine
feeders to females w ith clear te rre stria l preferences. Sim ilarly, pre lim ina ry m ercury burden data was
also observed to vary between females and, additionally, be transferred to eggs and chicks during
breeding season. These data suggest th a t parental feeding habits may, indeed, influence exposure
risk o f chicks to m ercury contam ination in the environm ent.
References
Fry D.M. 1995. Reproductive effects in birds exposed to pesticides and industrial chemicals.
Environm ental Health Perspectives 103:165-171.
Gochfeld M. e t a i 2002. New Jersey M ercury Task Force Report. Volum e II - Exposure and Impacts.
New Jersey, Environm ental and O ccupational Health Sciences Institute. U niversity o f Medicine &
D entistry o f New Jersey.
Hoffman D., B. Rattner, G.A. Burton., J. Cairns et a i 2003. H andbook o f Ecotoxicology. Boca Raton
(FL), Lewis Publishers.
Stearns S.C. 1992. The evolution o f life histories. O xford, O xford U niversity Press.
Sundlof S.F., M.G. Spalding, J.D. W entw orth and C.K. Steible. 1994. M ercury in livers o f w ading birds
(ciconiiform es) in southern Florida. Archives o f Environm ental C ontam ination and T oxico lo g y
27(3):299-305.
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Probiotics as biological control agent in sea bass larviculture
Schaeck Marlieri, Annem ie Decostere, Evelien De Swaef and Wim Van Den Broeck
D epartm ent o f M orphology, Faculty o f Veterinary Medicine, Ghent University, Salisburylaan 1 33,
B-9820 Merelbeke, Belgium
E-mail: marlien.schaeck@ uqent.be
To ham per the emergence o f acquired resistance, the use o f antim icro bial agents should be curbed
in both human and (aquatic) veterinary m edicine. However, sim ultaneously, disease outbreaks are
increasingly being recognized as a sig n ifica n t constraint on aquaculture production and trade,
affecting the econom ic developm ent o f the sector. The use o f probionts as a biological control
agent in aquaculture is popular as an alternative fo r the use o f antim icro bial agents in disease
prevention and production enhancem ent. Nowadays, new and fascinating research questions arise
regarding the mechanisms th ro ug h which the probionts may act. U nderstanding p ro b io n t action
may p erm it to u tilize the rig h t strain to protect from , trea t or prevent specific disorders.
The aim o f th is study is to isolate and select probionts fo r use in sea bass (D icentrachus labrax)
larviculture and to unravel th e ir modes o f beneficial activity. Two hundred and six isolates were
p rim arily isolated fro m g u t o f larval and a du lt sea bass from varying origin and evaluated in v itro
using various m echanisms o f selection including a ntagonistic a ctivity against e ig h t sea bass
pathogens, adhesion to sea bass g u t mucus and a lack o f hem olytic activity. Following, tw e nty
isolates e xh ib itin g positive in v itro results were w ithheld and are cu rren tly being assessed in vivo
fo r a lack o f harm tow ards the larval host. The isolates th a t are harmless w ill be identified using
16S rRNA gene partial sequencing and fu rth e r evaluated in term s o f th e ir protective capacities
during an e xperim ental challenge and stress test. The isolates exerting a positive effect on larval
survival and developm ent, w ill consequently be used to unravel th e ir mechanism o f action in the
near fu tu re , w ith a focus on disease resistance in the host organism . This w ill be realized by
applying innovative techniques e.g. g n o to b io tic larval m odel systems, im m une prim ing and
tissu e/ce ll-sp ecific gene analysis using laser capture m icrodissectioning.
- 92 -
What influences predation by Coralliophila? Exploring the
relationships between corals, sym biotic zooxanthellae, and
corallivorous gastropods
Schmidt-Petersen Julia', O livier De C lerck' and Rachel C ollin 2
' W orking Group Phycology, Ghent University, Krijgslaan 281 S8, 9000 Gent, Belgium
E-mail: iulia.schm idtpetersen@ qm ail.com
2 Research Station Bocas del Toro, Sm ithsonian Tropical Research Institute, 9100 Panama C ity PI,
W ashington, D.C. 20521-9100, USA
Coral feeding gastropods can occur in high num bers and may have severe impacts on reefs, but
th e ir ecology is still poorly understood. This study explores which intraspecific variations o f corals
(such as depth, color m orph and associated zooxanthellae strain) influence predation by
corallivorous gastropods. Samples, field data and pictures o f corals and snails were taken in reefs
around Bocas del Toro, in the Caribbean region o f Panama. Zooxanthellae were identified by
Denaturing Gradient Gel Electrophoresis (DGGE), a fte r DNA was obtained from corals w ith a recently
developed m icro-invasive technique, using a syringe w ith a blunted needle, and was herein proven
to be applicable fo r a variety o f coral species. The study found th a t (1) corals o f the M onastraea
a n n u la ris com plex th a t incorporate w hite structures (‘w hite layer’) o f unknow n origin in th e ir tissue
are less often infested by C oralliop hila abbreviata. (2) When associated w ith one rare sym biont
strain o f clade B (8%), A cro po ra cervicornis bears higher densities o f C. caribaea than if associated
w ith the other, more com m on strain o f clade A (92%). General occupation rates o f A. cervicornis in
Bocas del Toro are low fo r C. a b b re via ta (4%) and high fo r C. caribaea (63%) com pared to other
locations in the Caribbean. (3) C. caribaea d iffers from its congener by not undergoing sex change,
a less destructive feeding strategy by prudent sessile feeding, which does not cause open lesions,
and seem ingly rem aining longer on the same coral polyp. T ogether w ith the known fact th a t it
tran sm its white-band-disease, the study suggests th a t high abundances o f C. a b b re via ta on
A. cervicornis are more alarm ing than o f C. caribaea, which should be addressed in fu rth e r studies.
- 93 -
Microbial piezophysiology: which role fo r high pressure in oil
degradation?
Scoma A lb e rto 1, Ramiro Vilchez-Vargas1, Marta Barbato2, Francesca M apelli2, Sara Borin2,
Daniele D affonchio2 and Nico Boon'
1 Laboratory o f M icrobial Ecology and T echnology (LabMET), Ghent U niversity
Coupure Links 653, B-9000, Gent, Belgium
E-mail: nico.boon@ uqent.be
2 D epartm ent o f Food, Environm ental and N utrition a l Sciences (DeFENS), U niversity o f Milan
via Celoria 2, 20133, Milano, Italy
Most o f the scientific research carried o ut so fa r in m icro biolo gy and biotechnology is focused on
the understanding o f biological kinetics at am bient pressure. This cond itio n may characterize the
large m a jo rity o f m icrobes on d ry land, w hile it does not apply to those living in the sea. Oceans are
populated by a large variety o f m icroorganism s th a t are able to survive in e xtre m ely harsh
co nditions (Kato e t a i, 1998). Here, m etabolic pathways are typ ically affected by high pressure (as
well as by low tem peratures) in a manner th a t is not com p le te ly clear. When oil spills occur, a
relevant am ount o f hydrocarbons (HCs) is released into the environm ent (A dcroft e t a i, 2010). In
the case o f marine accidents, such com pounds w ill spread horizontally, eventually reaching the
closest shores, and vertically, dro pp ing downwards to the sea flo or. Here, although HCs are present
in nature, marine ecosystems may be able to degrade only a very m inor fraction o f such spills.
Typically, one o f the main reasons fo r HCs low b io de gra da bility is th e ir low s o lu b ility in water,
preventing an e fficie n t m icrobial uptake. It is known th a t high pressure increases oil s o lu b ility in
w ater (Srivastan et a i, 1992), while also su pp orting an increase in the flu id ity o f cells’ membrane
(Bartlett, 2000), both easing m icrobial access to HCs. M icroorganism s responsible fo r
biorem ediation are known to produce surfactants, which fu rth e r enhance oil solubility, a co ndition
known to feature the best degraders (Yakim ov et a i, 1998). However, these factors are not
su fficien t to allow fu ll rem ediation, and the m a jo rity o f the spilled HCs persist fo r decades (Reddy ex
a i, 2002). In ord er to gain fu rth e r insights on the role o f hydrostatic pressure on the catabolic
pathways trigg ered during HCs degradation, we tested fo u r d iffe re n t HCs degraders (belonging to
the genera A lca nivo ra x and M arinobacter, three o f which are new isolates fro m surface w ater and
sedim ent) at three d iffe re n t pressures (1, 55 and 105bars, correspondent to about 0, 550 and
1050m seawater-depth), using dodecane (Cl 2) as a m odel HC. Evaluation o f cells grow th (as optical
density) was coupled to a num ber o f biochem ical analyses, such as oxygen respiration, carbon
dioxide production, h ydro p h o b icity te st (in directly expressing the degree o f access to HCs) and
phospholipid fa tty acids (PLFA) analysis. Further, tra n scrip to m ic analyses have been conducted to
check the expression o f the alkane monooxygenase gene (alkB) and the cytochrom e P450 (CYP153),
the m ost known genes responsible fo r HC degradation, and to unravel which o th e r genes are
triggered by high pressure in such conditions and are pote ntia lly involved in the degradation o f
HCs.
References
A d cro ft A., R. Hallberg, J.P. Dunne, B.L. Samuels, J.A. Galt, C.H. Barker and D. Payton. 2010.
Sim ulations o f underw ater plumes o f dissolved oil in the G ulf o f Mexico. Geophysical Research
Letters 37(1 8): 1-10.
Bartlett D. 2000. M icrobial adaptation to the psychrosphere/piezosphere. In: M olecular Marine
M icrobiology. Douglas H.B. (Ed.). W ym ondham, N orfolk, England, UK: H orizon Scientific Press,
p. 1 85-202.
Kato C., L. Li, Y. Nogi, Y. Nakamura., J. Tamaoka. and K. H orikoshi. 1 998. Extrem ely Barophilic
Bacteria Isolated fro m the Mariana Trench, C hallenger Deep, at a Depth o f 11,000 Meters.
Applied Environm ental M icrobiology 64(4):1 510-1513.
Reddy C .M., T.l. Eglinton, A. Hounshell., H.K. White, L. Xu., R.B. Gaines, G.S. Frysinger. 2002. The
West Falmouth oil spill a fte r th irty years: The persistence o f petroleum hydrocarbons in marsh
sediments. Environm ental Science & T echnology 36(22):4754-4760.
Srivastan S., N.A. Darwish, K.A. Gasem and R.L. Robinson Jr. 1 992. S o lub ility o f methane in hexane,
decane, and dodecane at tem peratures from 311 to 423 K and pressures to 10.4 MPa. Journal
o f Chemical and Engineering Data 37(4):516-520.
Yakim ov M.M., P.N. Golyshin, S. Lang, E.R.B. Moore, W.R. Abraham , H. Lunsdorf and K.N. Tim m is.
1998. A lca nivo ra x b orkum en sis gen. now, sp. nov., a new, hydrocarbon-degrading and
surfactant-producing marine bacterium . International Journal o f Systematic Bacteriology
48:339-348.
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C om paring m eteorological data from weather stations and in situ
data loggers in mangrove areas in South Africa
Seghers Stephie1, Katrien Q u isth o u d t2, Farid D ahdouh-G uebas'2and Nico Koedam'
' Laboratory o f Plant Biology and Nature Management, Vrije U niversiteit Brussel (VUB)
Pleinlaan, 2, B-1050, Brussels, Belgium
E-mail: Stephie.Seqhers@vub.ac.be
2 Laboratory o f Systems Ecology and Resource Management, Université Libre de Bruxelles
Av. F.D. Roosevelt 50, B-1050, Brussels, Belgium
Data from w eather stations are not always accurate fo r ecological studies when the distance from
the study site to the nearest weather station is large. Therefore it can be useful to measure
tem perature and relative h u m id ity by means o f data loggers at the site o f interest, next to records
from stations. Deviations are caused by the existence o f m icroclim ates. Moreover, fo r instance in
fo re st ecosystems, in situ data can be more e xplan atory when they are measured at d iffe re n t
heights (e.g. in the crown, in the understorey and in the soil at the below ground roots), compared
to w eather stations where the variables are measured at a specific standard height. When both data
sources are available, it is also interesting to compare data fro m w eather stations and data loggers
and to define if the deviation is significant.
The study area is the mangrove d is trib u tio n along the north-south oriented east coast o f South
Africa. Tem perature and relative h u m id ity are available from data loggers in fo u r m angrove sites
situated at d iffe re n t latitudes: Mgeni, Mngazana, N xaxo-Nqusi and the m ost southern mangrove
forest, Nahoon. These data are measured from March 2011 u ntil Septem ber 2013. Weather stations
th a t are situated m ost closely to the m angrove sites, are chosen fo r the com parison a fte r correction
fo r a ltitude. Then air tem peratures and relative hum idities from the stations are compared to in situ
data in the crown-, the understorey- and the soil-layer. The analyses are done by adapting the
m ethod developed by Kolias e t al. (201 2) to the coastal system.
This study dom ain is very explorative, as there are few cases in which m eteorological data from a
weather station are com pared to in situ m easurements. Our results are im p o rta n t fo r the
understanding o f the im pact o f clim ate on the latitud in al lim it o f mangroves in South A frica and fo r
the ecology o f coastal ecosystems in general.
References
Kolias C., C.F. Randin, Y. Vitasse and C. Körner. 201 2. C hapter 3: How accurate can weather stations
predict tem peratures at tree species lim its? A g ric u ltu ra l and Forest M eteorology. 33-47p.
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Ocean p h ila n th ro p y to feed marine scientific knowledge
Seysjan, Tina Mertens and André Cattrijsse
Flanders Marine Institute (VLIZ)
InnovOcean site, W andelaarkaai 7, B-8400 Oostende
E-mail: ian.sevs@vliz.be
In 2013 the Flanders Marine Institute (VLIZ) explored the possibilities to initiate a p hilan thro py
initiative. In th is way, VLIZ wants to o ffe r people and companies w ith a passion fo r the sea the
o p p o rtu n ity to co ntribu te to a sustainable and healthy sea. From 2014 onwards, VLIZ w ill be using
its m em bership fees and welcomes donations, bequests and all sorts o f financial co ntribu tion s,
which w ill be spent to expand and develop the scientific knowledge regarding coastal and marine
areas.
Eligible projects should co ntribu te to the scientific knowledge and knowledge b uilding o f coastal
and marine areas anywhere in the w orld and should bear a neutral, objective message. The initiative
also needs to push forw ard a more sustainable use o f our seas and ocean by generating new
scientific knowledge and data measurements. For instance, projects can be elaborated to collect
scientific data concerning the condition o f the sea as well as the setup and developm ent o f specific
m on itoring campaigns and networks. A ll th is is done not only in close collaboration w ith scientists
but w ith the general public as well. Such citizen science initiatives result in a sign ifican t increase in
public support.
Depending on the p hila n th ro p y budget, the available funds w ill be used fo r projects belonging to
one o f the three main categories:
(1) Category 1 - Sea observation netw orks (‘citizen science’);
(2) Category 2 - Education and long-term data sets;
(3) Category 3 - Developm ent o f new equipm ent.
VLIZ identifie d several possible projects, being:
(1) ‘S eaW atch-B ’, a Belgian beach o b s e rv a tio n n e tw o rk is designed to generate an accessible but
sustained long-term m on itoring netw ork fo r the Belgian coastal waters, based on a netw ork o f
volunteers supervised by experts.
(2) ‘S c ie n c e -s h ip ’ actively involves pleasure craft in m aritim e surveillance. By providing them w ith
targeted tra in in g and m easuring e quipm ent th ey can generate a m u ltip lica tio n o f in s itu data.
O ptionally, connection can be found w ith running initiatives such as the ‘Ocean Sampling Day’
initiative h ttp ://w w w .m ic ro b 3 .e u /o s d .
(3) ‘ Build y o u r o w n sea r o b o t’ enables young people, w ith technological interest, in developing
new sea-measuring equipm ent.
More inform a tion can be found at: h ttp ://w w w .v liz .b e /e n /v o u r-c o n trib u tio n .
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C om bining GPS tracking and stable isotope analysis to predict
changes in guii dynamics
Sotillo A le ja n d ro 1, Eric Stienen2, Magda V in cx3 and Luc Lens'
1 T errestrial Ecology Unit, Ghent U niversity
K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium
E-mail: aleiandro.sotilloqonzales@ uqent.be
2 In stitu u t voor Natuur- en Bosonderzoek
Kliniekstraat 25, B-1070 Brussels, Belgium
3 Marine Biology Section, Ghent U niversity
Krijgslaan 281, Campus Sterre - S8, B-9000 Ghent, Belgium
During the second half o f the 20th century, populations o f Herring Guii (Larus argentatus) and
Lesser Black-backed Guii (Larus fuscus) have grown su bstantially along the coasts o f the North Sea.
T he ir protected status, and a dd itional food supply in the fo rm o f urban waste and fish e ry discards,
are considered responsible fo r the p ro life ratio n o f these species. Belgian populations o f Herring and
Lesser Black-backed Guii breed m ainly on the docks o f the o ute r Port o f Zeebrugge and the roofs o f
the city o f Ostend. They are hig hly dependent on anth ro p ic sources o f food, nam ely fishery
discards, which m ig ht be crucial during the chick rearing stage o f the breeding season. The
prospect o f a strong drop in the production o f discards in the near fu tu re brings up the question on
which responses can be expected fro m large gulls in term s o f habitat use and feeding patterns, in a
co nte xt o f global decline o f th e ir populations.
To answer th is question, I study the habitat use, fo od dependencies and m ovem ent patterns o f
breeding L. fuscus and L. a rg en ta tus using a com bination o f GPS tracking and stable isotope
analysis techniques. Data from the firs t breeding season show the im portance o f specific, individual
and seasonal variation in habitat use. Specific variation is driven by the d iffe re n t fo ra gin g niche o f
the tw o studied species, which overlaps m arginally. Individual variation suggests the developm ent
o f particular fo ra gin g strategies th a t may be influenced by ontogeny. Seasonal variation reflects
changes in n u tritio n a l and energetic dem ands o f the breeding population, determ ined by the stage
o f the breeding season: egg-laying, hatching, chick-rearing, fle dg in g and post-fledging.
GPS tracking data o f fu tu re breeding seasons w ill inform on annual variations in habitat use. Stable
isotope ratio analyses w ill inform on the real dependence o f the breeding population on each o f its
main food sources at the d iffe re n t stages o f the breeding season.
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The European Marine Observation and Data Netw ork (EMODnet)
central portal
Souza Dias Francisco, Simon Claus and Francisco Hernandez
Flanders Marine Institute (VLIZ)
InnovOcean site, Wandelaarkaai 7, B-8400 Oostende, Belgium
E-mail: info@ em odnet.eu
Based on an extensive one-year consultation phase, the European Com m ission (EC) published a
M aritim e Policy Blue Book in 2007. One o f the key-actions was the creation o f a sustainable
European Marine Observation and Data N etwork (EMODnet). This data infrastructure would allow
Europe’s in d u stry and academia to fin d, access, assemble, and apply data collected th ro ug h marine
observations e fficie n tly and rapidly. Since May 2009, six preparatory actions were set up creating
d iffe re n t p ilo t data portals fo r m arine data.
In 201 3, a fo llo w -u p phase was launched by the EC w ithin the fram e w o rk o f the ‘ Knowledge base fo r
grow th and innovation in ocean economy: assem bly and dissem ination o f marine data fo r seabed
m ap pin g ’. A netw ork o f more than 110 partners from all European m aritim e countries is now
assem bling e xistin g data relating to the environm ental status o f sea basins; processing data to
create data products in interoperable form ats, such as web map services; and assessing th e ir
accuracy and precision. The netw ork is structured in 7 them atic areas: hydrographic data, marine
geological data, chem ical data, physical data, seabed habitats, biological data, and the recently
added lot gathering data on human activities at sea.
Now, the construction o f a central EMODnet portal is under way, providing easy access to and
visualization o f the them atic data products developed under the d iffe re n t them atic portals. The
central Portal w ill provide a focal landing page where EMODnet users can fin d links and inform ation
about the data products com piled by the d iffe re n t them atic portals, and w ill later include specific
to ols to visualize, access and use the d iffe re n t EMODnet data products. The central landing page is
cu rren tly available at h ttp ://w w w .e m o d n e t.e u
- 98-
Study and m odelling o f DMSP pro duction and its conversion into DMS
by North Sea specific p h ytop lan kton
Speeckaert Gaëlle', Christiane Lancelot1, Nathalie Gypens1 and A lb erto Borges2
1 Ecologie des Systèmes Aquatiques, Faculté des Sciences, Université Libre de Bruxelles, CP-221,
Bd du Triom phe, B-l 050, Belgium
E-mail: Gaelle.Speeckaert@ulb.ac.be
2 In s titu t de Physique (B5), Unité d ’Océanographie C him ique, Université de Liège, B-4000, Belgium
D im ethylsulphide (DMS) is a clim atic gas affecting the global clim ate th ro ug h the production o f
atm ospheric aerosols (Charlson e t al., 1987). The ocean is the main natural source (Bates e t al.,
1992) as d im ethylsu lp ho n io pro pion ate (DMSP), the DMS precursor, is synthesized by m ainly
phytoplankton (e.g. Stefels e t al., 2007). The lack o f correlation between observed DMS and
phytoplankton d istrib u tio n s is explained by the co m p le xity o f DMSP production and conversion to
DMS pathways. Indeed the a b ility to synthetize DMSP is species-specific (Keller et al., 1989; Matrai
and Keller, 1994) and varies w ith environm ental co nd itio ns (Keller and Korjeff-Bellows, 1996;
Stefels, 2000). Moreover, the enzym atic cleavage o f DMSP in DMS can e ithe r be perform ed by
phytoplankton (Stefels and D ijkhuizen, 1996) or bacterial lyases (Kiene and Bates, 1990). In this
context, th is thesis aims to im prove the knowledge and m odelling o f DMS production and its
em ission to the atm osphere in the coastal N orth Sea. The research strategy com bines 3 approaches:
laboratory-controlled
expe rim en tatio n
w ith
monospecies
phytoplankton
cultures,
field
m easurements, m echanistic m odelling. The DMSP cellular concentrations and regulation by
environm ental co nd itio ns (salinity, tem perature, lig h t and nutrients) and the DMSP-lyase a ctivity o f
key-phytoplankton species isolated fro m the North Sea w ill be measured by gas chrom atography.
These data w ill be synthesised and integrated in the m echanistic m odel MIRO-DMS. This model
results fro m the coupling between a DMS m odule and the ecological m odel MIRO th a t describes
phytoplankton successions and the associated C, N, P and Si cycling in the North Sea. Thereafter,
th is m odel w ill be applied to the Southern Bight o f the North Sea, and DMS(P) and phytoplankton
sim ulations w ill be compared w ith fie ld measurem ents obtained along a seasonal cycle. Once
validated, the m odel w ill be analysed fo r assessing biotic (phytoplankton diversity) and abiotic
(tem perature, light, salinity, nutrients, w ind speed) controls o f DMS production and its emission to
the atmosphere.
References
Bates T.S., B.K. Lamb, A. G uenther. J. Pignon and R.E. Stoiber. 1 992. Sulfur em issions to the
atm osphere fro m natural sources. Journal o f A tm ospheric C hem istry 14:31 5-337.
Charlson R.J., J.E. Lovelock, M.O. Andreae and S.G. Warren. 1987. Oceanic phytoplankton,
atm ospheric sulphur, cloud albedo and clim ate. Nature 3 26 :6 5 5 -6 6 1 .
Keller M. D., W.K. Bellow and R.R.L. Guii lard. 1989. D im ethylsulfide production in marine
phytoplankton. In: Saltzman E.S., Cooper W.J. (Eds). Biogenic s u lfu r in the environm ent.
Am erican Chemical Society, W ashington DC, p .16 7 -1 8 2 .
Keller M.D. and W. Korjeff-Bellows. 1996. Physiological aspects o f the production o f
d im eth ylsu lfo n io p ro p io n a te (DMSP) by marine phytoplankton. In: Kiene R.P., P. Visscher,
M. Keller, G. Kirst (Eds). Biological and environm ental ch em istry o f DMSP and related sulfonium
com pounds. Plenum Press, New York, p .13 1 -1 4 2 .
Kiene R.P. and T.S. Bates. 1990. Biological removal o f d im ethyl sulfide from seawater. Nature
3 45 :7 0 2 -7 0 5 .
Matrai P.A. and M.D. Keller. 1994. Total organic su lfu r and d im eth ylsu lfo n io p ro p io n a te in marine
phytoplankton: intra cellula r variations. Mar. Biol. 1 19 :61 -68 .
Stefels J. 2000. Physiological aspects o f the production and conversion o f DMSP in marine algae and
higher plants. J Sea Res 43:1 83-1 97.
Stefels J. and J. D ijkhuizen. 1996. Characteristics o f DMSP-lyase in Phaeocystis sp. (Haptophyceae).
Mar. Eco I. Prog. Ser. 131 3 0 7 - 3 13.
Stefels J., M. Steinke, S.M. Turner, G. Malin and S. Belviso. 2007. Environm ental constraints on the
production and removal o f the clim a tically active gas d im ethylsulphide (DMS) and im plications
fo r ecosystem m odelling. Biogeochem istry 83(1-3):245-275.
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GPS tags reveal movements o f Herring and Lesser Black-backed Gulls
along the Belgian coast
Stienen EricW .M .1, Peter Desm et1, Luc Lens2, Hans Matheve2, Francisco Hernandez3
and W illem Bouten4
1 Research Institute o f Nature and Forest (INBO), K liniekstraat 25, B-1070 Brussels, Belgium
E-mail: Eric.STIENEN@inbo.be
2 T errestrial Ecological Unit (TEREC), Ghent University, B-9000 Ghent, Belgium
3 Flanders Marine Institute (VLIZ), InnovOcean site, Wandelaarkaai 7, B-8400 Ostend, Belgium
4 Institute fo r Biodiversity and Ecosystem Dynamics (IBED), U niversity o f Am serdam , 1090GE
Am sterdam , the Netherlands
As part o f o u r te rre stria l observatory fo r LifeWatch, the Research Institute fo r Nature and Forest
(INBO) is tracking large birds w ith ligh tw eigh t, solar powered GPS tags. The project builds upon the
extensive knowledge INBO has acquired over the last 12 years in studying postnuptial m igration,
and mate and site fid e lity o f large gulls, using sightings o f colour-m arked individuals ringed in
Belgium.
The GPS tags, which are developed by the U niversity o f Am sterdam Bird Tracking System
(h ttp ://w w w .u v a -b its .n l) and funded by LifeWatch, allow us to study the m igration patterns and
habitat use o f the gulls in more detail, and are no longer biased tow ards locations where observers
can see the birds. In 2013, we equipped 25 Lesser Black-backed Gulls Larus fuscus (LBBG) nesting in
the port o f Zeebrugge and 5 Herring Gulls L. a rgentatus (HG) nesting in the p ort o f Ostend w ith the
GPS tags, which autom atically record the m ovem ents o f the gulls over the next few years.
The study is conducted in close collaboration w ith the T errestrial Ecological Unit (TEREC) o f the
University o f Ghent, the Flanders Marine Institute (VLIZ) and the U niversity o f A m sterdam (UvA).
Here we report on the specific m ovements o f one breeding Lesser Black-backed Guii and tw o
Herring Gulls durin g and a fte r the breeding season, showing how the m ovem ents o f the gulls vary
during the course o f the breeding season and fluctuate w ith tid a l movements. The m ovements are
visualized w ith CartoDB, an open source to o l to visualize and analyse geospatial data on the web.
The GPS positions o f the LBBG called Eric show th a t he changes his fo ra gin g behaviour to fu lfil the
grow ing energetic needs during the breeding season. When s till incubating eggs in Zeebrugge, Eric
m ainly foraged in the a gricu ltu ra l areas to the southeast o f the colony. He also made regular trip s to
Moeskroen, about 65km from the colony site, to feed on potato chips th a t were declared u n fit fo r
human consum ption and dum ped in containers. A fte r hatching o f the eggs and w ith the grow th o f
the chicks, energy needs rapidly increased and Eric more and more foraged at sea probably to feed
on energy rich discarded fish.
During incubation o f the eggs in May, Jurgen, a HG th a t nested on a r o o fto p in Ostend, m ost often
foraged close to his nest (w ithin 1Okm) m ainly at the hard substrates probably to feed on crabs and
shellfish. Sometimes he made longer trip s to the open sea. D uring the chick-rearing season Jurgen
more often made trip s to the sea, up to about 30km fo rm the colony. A fte r his chicks had fledged
(August and September) and energy demands decreased his foraging range reduced and he alm ost
exclusively foraged and rested at the hard substrates (jetties) in the v ic in ity o f Ostend. In October
Jurgen again changes his fo ra gin g strategy and he now regularly feeds inland in the agricultural
areas to the southeast o f Ostend and less often returns to the colony site.
Finally we show the m icro-scale movements o f Anne, a HG th a t nested in Ostend. Even more than
Jurgen, Anne was regularly fo un d feeding and resting on the je ttie s and the beaches near Ostend. If
we zoom in on her behaviour clear tid a l patterns can be seen. A t low tide, Anne used the m udflats
and the lower parts o f the je ttie s to feed on arthropods and shellfish. D uring high tide she rested on
the higher parts o f the je ttie s or at the beach.
These analyses use o nly a small part o f the tracking data o f the gulls th a t were received until now.
We hope to answer many research questions at m ultiple scales w ith the data gathered over the next
few years. These data w ill also be made available as open data to stim ulate fu rth e r use. A subset o f
the data fo r the LBBG Eric can already be visualized and dow nloaded at
h ttp ://life w a tc h .in b o .b e /b lo q /p o s ts /tra c k in q -e ric .h tm l.
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Copepods prom ote nitrogen retention in estuarine sediments
Stock W illem ' , Kim Heylen2, Koen Sabbe3, Anne W illem s2 and Marleen De T ro ch 1
1 Marine Biology, Biology Departm ent, Ghent University, Krijgslaan 281 - S8, B-9000 Ghent, Belgium
E-mail: Willem.Stock@ Uqent.be
2 Laboratory o f M icrobiology (LM-UGent), D epartm ent o f Biochem istry and M icrobiology, Ghent
University, K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium
3 Laboratory o f P rotistology and A quatic Ecology, Biology Departm ent, Ghent U niversity
Krijgslaan 281 - S8, B-9000 Gent, Belgium
During the past century anthropogenic activities have d ram atically increased the am o un t o f reactive
nitrogen on Earth. It has been estim ated th a t nitrogen inputs have increased as much as te n-fo ld in
coastal ecosystems. As a result, these o rig in a lly n itro g e n -lim ite d areas have become severely
eutrophied.
D en itrifica tion is an essential step in the nitrogen cycle as it is capable o f counteracting
eutrophication by rem oving the excess o f reactive nitrogen from the ecosystem. In the past
decades, much research has been devoted to unravelling which organism s affect nitrogen cycling in
inte rtid a l sediments. Until now, these studies alm ost exclusively focussed on the influence o f
m icrophytobenthos or m acrofauna on d e n itrifica tio n . The effects o f m eiofauna (e.g. nem atodes and
copepods), the interm ediate tro p h ic level, on the N fluxes have a lm ost com pletely been neglected,
notw ithstanding the fact th a t these abundant organism s interact in num erous ways w ith bacteria,
m icrophytobenthos and macrofauna.
The aim o f th is study was to investigate the im pact o f the m eiofauna and its interactions w ith
diatom s and bacteria on d e n itrifica tio n in marine sediments.
To th is end, we used a m icrocosm approach in which (1) copepods, (2) spent m edium from
copepods, (3) diatom s (N avicula sp.) or (4) a com bination o f copepods and diatom s were added to
defaunated estuarine sediments. The m icrocosm s were incubated fo r seven and a half days, after
which the n u trie n t concentrations and d e n itrific a tio n potential (a pro xy fo r the d e n itrifica tio n
a ctivity in the m icrocosm ) were measured. The excretion products o f copepods proved to be an
im p o rta n t source o f both am m onium and phosphate. Furtherm ore, the presence o f copepods and
th e ir excretion products reduced d e n itrific a tio n rates in the m icrocosm s. By providing the system
w ith more n utrients th ro ug h th e ir excretions and reducing the am ount o f active nitrogen th a t was
lost th ro u g h d e n itrifica tio n , copepods seemed to enhance e utrophication. This w ould benefit the
copepods as it w ill prom ote the grow th o f th e ir food sources, i.e. bacteria and diatom s. However,
these fin d in g s should be interpreted w ith care, as field ve rificatio n remains necessary. This is the
firs t study th a t provides clear evidence fo r the im pact o f m eiofauna on d e n itrifica tio n .
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Ecosystem-based assessment o f the Malindi-Ungwana Bay prawn
fishery using ecological indicators
Swaleh Khyria1 2, Boaz Kaunda-Arara 2, Renison Ruwa1and Philip Raburu2
1 Kenya Marine and Fisheries Research Institute, PO Box 81651 Mombasa, Kenya
E-mail: khvriask@ qm ail.com , reniruwa@ vahoo.com
2 D epartm ent o f Fisheries and A quatic Sciences, U niversity o f Eldoret, PO Box 11 25 Eldoret, Kenya
The study aimed to describe indicators th a t w ill co ntribu te to developm ent o f an ecosystem-based
approach to fisheries m anagem ent (EAFM) o f prawn resources in the M alindi-Ungwana Bay, Kenya. A
comprehensive EAFM is required to h oiistically assess and manage fisheries resources and th e ir
associated habitats. The project identified and assessed ecological indicators based on the
objectives o f su stain ab ility o f harvests, b io dive rsity conservation, and maintenance o f habitat
quality. A desktop analysis was perform ed on data sourced from ; the State D epartm ent o f Fisheries,
Research vessels, KMFRI, and on-project fie ld w ork. Trends in historical landings (1985-2010) o f the
prawns fro m the M alindi-Ungwana Bay were analysed using LOWESS. Num ber-size spectra analysis
was used to assess the ecological state o f the bay w hile, Biomass T ro p hic Level spectra (BTLS)
analysis was applied as a potential to o l fo r analysing m u lti-fa cto r effects on the bay. Indiseas based
ecosystem indicators were used to q u a n tify the im pact o f prawn fis h e ry on the bio dive rsity o f the
bay. Results indicate a long-term series w ith tw o peaks (in 1997 and 2000) in historical landings o f
penaeid shrim ps w ith a m onotonous decline in catches fro m 2002. Num ber -size spectra analysis
made from artisanal landings (2008-2012) indicated effects o f fish in g on the ecosystem. The
num ber-size spectra results showed increased fish in g m o rta lity w ith tim e (2008-2012) and a
general increase in fisheries p ro d u ctivity o f the bay. BTLS analysis using the fish by-catch data
indicated reduced levels o f biomass across tro p h ic levels and a decline in tro p h ic levels o f the fish
species caught, indicating a fishing - down o f the food web. Biodiversity and conservation based
indicators adopted fro m the Indiseas program showed the M alindi-Ungwana Bay ecosystem is
ecologically degraded in term s o ffis h sizes, tro p h ic characteristics and pro po rtio n o f predators. The
study recomm ended adoption o f the described ecological indicators and tools as means fo r
evaluating and m o n itoring the M alindi-Ungwana Bay resources and ecosystem status. However,
there is need to initiate more long-term m on itoring program s in order to strengthen the tem poral
scale o f analysis. A d d itio n a l socio-econom ic and biological data w ill be needed in order to develop a
holistic EAFM m odel fo r the m anagem ent o f the M alindi-Ungwana Bay resources.
References
Andersen K.H. andJ.E. Beyer. 2006 A sym p totic size determ ines species abundance in the marine
size spectrum . Am. Nat. 168:54-61.
Anon. 2001. Report on the scientific inform a tion and conservation sub- com m ittee. Prawn fish ery in
Kenya marine waters. KMFRI Unpublished report.
Beyer J.E. 1989. R ecruitm ent sta b ility and survival - simple size-specific th eo ry w ith exam ples from
the early life dynam ic o f marine fish. Dana 7 :45 -1 4 7.
Bianchi G., H. Gislason, K. Graham, L. Hill, K. Koranteng, S. M anickchand-Heileman, S., I. Paya e t al.
2000. Im pact o f fish in g on size com position and d ive rsity o f demersal fish com m unities. ICES
Journal o f Marine Science 5 7:5 58 -57 1.
Clarke K.R. and R.M. Warwick. 1998. A ta xon om ic distinctness index and its statistical properties. J.
Appl. Eco I. 3 5 :5 2 3 -5 3 1 .
Cleveland W.S. 1979. Robust locally w eighted regression and sm oothing scatterplots. J. Am er. Stat.
Ass. 7 4:8 2 9 -8 3 6 .
Daan N., H. Gislason, J.G. Pope. And J. Rice. 2005 Changes in the North Sea fish com m unity:
evidence o f indirect effects o f fishing? ICES J. Mar. Sei. 62:177-1 88.
Degnbol P. and A. Jarre. 2004. Review o f indicators in fisheries m anagem ent developm ent
perspective. A frican Journal o f Marine Science 26:303-326.
FAO (Food and A g ricu lture O rganization). 2003. Fisheries management. 2. The ecosystem approach
to fisheries. FAO Tech. Guidelines fo r Responsible Fisheries 4, Suppl. 2, 112p.
Fennessy S.T. 2002. Prelim inary investigations o f a bycatch reducing device fo r the Tugela bank
prawn traw l fish e ry in Kwa-Zulu Natal. South A frican Association fo r marine Biological Research.
Unpublished report.
Fulanda B. 2003. Shrim p traw ling in Ungwana Bay: a th re at to fish e ry resources. In: Hoorweg J.,
M uthiga N. (Eds). Recent advances in coastal ecology: studies from Kenya. PrintPartners
Ipskam p BV, Enschede, p .2 33 -2 4 2 .
- 102 -
Garcia S.M., A. Zerbi, C. Aliaum e e t al. 2002. The ecosystem approach to fisheries: Issues,
term inology, principles, in stitu tio n a l foundations, im plem entation and o utlook. FAO Fisheries
Technical Paper 443. Rome, FAO: 71.
Mwatha G.K. 2002. Assessm ent o f the prawn fishery, bycatch, resource-use conflicts and
perform ance o f the tu rtle excluder device. In: C urrent status o f traw l fish e ry o f M alindiUngwana Bay. KMFRI Tech Rep 1 2 /2 0 0 2 , pp 4 4-65
Pauly D., V. Christensen and C. Walters. 2000. Ecopath, Ecosim and Ecospace as to ols fo r evaluating
ecosystem im pact o f fisheries. ICES Journal o f Marine Science 5 7 :6 9 7 -7 0 6 .
Rosenberg. A.A. and V.R. Restrepo. 1994. U ncertainty and risk evaluation in stock assessment
advice fo r U.S. marine fisheries. Can. J. Fish. Aquat. Sei.
Rothschild B.J. 1996. Dynamics o f marine fish populations. Flarvard U niversity Press, Cam bridge,
Massachusetts, USA. 277 pp. 61
Shin Y.-J. and P. Cury. 2004. Using an individual-based m odel o f fish assemblages to study the
response o f size spectra to changes in fish in g. Can. J. Fish. Aquat. Sei. 6 1 :414-431
Thiebaux M.L., and L.M. Dickie. 1993. Structure o f the body-size spectrum o f the biomass in aquatic
ecosystems: a consequence o f allo m e try in p re d a to r-p re y interactions. Canadian Journal o f
Fisheries and A quatic Sciences 50:1308-1 317. 62
- 103 -
Effect o f induced anoxia on nematode densities, vertical d istrib u tio n
patterns and recovery at the G ulf o f Trieste (Northern A d riatic Sea)
Taheri M ehrshad12, Mateja Grego3, Bettina Riedel4, Magda Vincx' and Jan Vanaverbeke1
1 Marine Biology Research Group, Biology D epartm ent, Ghent University, Krijgslaan 281, S8,
B-9000 Ghent, Belgium
E-mail: m ehrshad.taheri@ uqent.be
2 Iranian National Institute fo r Oceanography, 9 Etemadzadeh Ave, West Fatemi Str, Tehran, Iran
3 Marine Biology Station Piran, National Institute o f Biology, Fornace 41, 6330 Piran, Slovenia
4 D epartm ent o f Lim nology and Oceanography, U niversity o f Vienna, Althanstrasse 14, 1090
Vienna, A ustria
Oxygen stress, including hypoxia and anoxia, is increasing w orldw ide due to natural and
anthropogenic impacts and has serious consequences fo r benthic ecosystem fu n ctio n in g (Chan et
al., 2008; Diaz and Rosenberg, 2008).
Response and recovery o f nematode com m unities to induced anoxia were investigated at the G ulf o f
Trieste, N orthern A d ria tic Sea. A noxia was induced fo r 7 days, 1 and 10 m onths in benthic
cham bers installed at 24m depth in silty sand sedim ent using the Experim ental A noxia Generating
Unit (EAGU, see Riedel e t al., 2012). A t each tim e, three cores (i.d. 4.6cm ) were collected in both
experim ental treatm ents and co n tro l situations. Cores were sliced into 7 depth layers: 0 -0 .5 ; 0.5-1 ;
1-1.5; 1.5-2; 2 -3 ; 3-4 and 4-5cm, stored in 4% form aldehyde and after extraction, nem atodes were
counted in each layer.
Total nematode density, and the vertical d is trib u tio n in the upper 2cm (0.5cm interval) and up to
5cm (1cm interval) were not sig n ifica n tly affected by anoxia after 7 days. In contrast, to ta l density
was clearly reduced after one m onth anoxia, and vertical d is trib u tio n patterns were altered. Our
results fu rth e r indicate th a t recovery o f nematode densities was not fu lly achieved after a recovery
period o f 10 m onths.
Our results indicate th a t nematodes were to le ra n t to short term anoxia (7 days). This may relate to
adaptation mechanisms o f nem atodes to live in naturally low oxygen environm ents. On the other
hand the negative effect on nem atode com m unities a fte r one m onth o f anoxia can be related to
increasing concentration o f hydrogen sulphide (Riedel et al., 2012) which can increase the negative
effects o f anoxia. It seems th a t com plete recovery o f nem atodes density requires a relatively long
period o f tim e. This can be due to persistent unfavourable conditions in the sedim ent, or autoecological features including nem atode reproduction capacity. However, more detailed (but
ongoing) analyses are needed to increase our understanding o f the effect on anoxia on nematode
com m unities (e.g. at species level).
References
Chan F. J.A. Barth, J. Lubchenco, A. Kirincich, H. Weeks, W.T. Peterson and B.A. Menge. 2008.
Emergence o f A noxia in the C alifornia C urrent Large Marine Ecosystem. Science 319:920.
Diaz R.J and R. Rosenberg. 2008. Spreading dead zones and consequences fo r m arine ecosystems.
Science 3 2 1 :926-929.
Riedel B., M. Zuschin and M. Stachowitsch. 201 2. Tolerance o f benthic m acrofauna to hypoxia and
anoxia in shallow coastal seas: a realistic scenario. Mar. Ecol. Prog. Ser. 4 5 8 :3 9 -5 2 .
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Extreme values o f Suspended Particulate M atter concentration and
th e ir relation to wave systems along the Belgian inner shelf
T hant Silvy1, M atthias Baeye2, Frederic Francken2, Michael Fettweis2, Jaak M onbaliu3
and David Van Rooij4
1 MSc student Marine and Lacustrine Sciences and Management, Ghent U niversity
E-mail: S.Thant@uqent.be
2 O perational D irectorate Natural Environm ent (OD Nature), Royal Belgian Institute o f Natural
Sciences (RBINS), Gulledelle 100, B-1200 Brussels, Belgium
Email: Matthias.Baeve@mumm.ac.be
3 D epartm ent o f Civil Engineering, Katholieke U niversiteit Leuven (KUL), Kasteelpark Arenberg 40,
B-3001 Leuven
4 Renard Centre o f Marine Geology (RCMG), D epartm ent o f Geology and Soil Science, Ghent
U niversity (UGent), Krijgslaan 281 S8, B-9000 Gent
SPM concentration is a key param eter to describe the environm ental status, and to evaluate and
understand the im pact o f human activities in nearshore areas. Long-term m easurem ents are needed
in ord er to resolve all variations in SPM concentration. Processes affecting SPM concentration are
turbulence, tides, neap-spring cycles, m eteorological events, season, and o the r long-term
flu ctua tion s. SPM concentration has been measured since 2005 at the MOW1 site, situated at about
5km northw est o f Zeebrugge in the h ig h -tu rb id ity zone o ff the Belgian-Dutch coast. The
m easurem ents have been carried out using a benthic trip o d th a t allowed m easuring during all
m eteorological conditions, including storm s.
Storm effects on sedim ent re-suspension and SPM concentration have been investigated using
m eteorological and wave data fro m IVA MDK (afdeling Kust - Meetnet Vlaamse Banken). SPM
concentration data fro m MOW1 (51°22.04’N 3°6.95’E) were estim ated using the backscatterance
from a 3MHz acoustic D oppler p ro filin g cu rren t meter. Because o f the large am ount (~ 1220 days) o f
SPM concentration data, an autom atic detection a lg o rith m fo r identifying extrem e events was
developed. A low-pass filte r was run on the SPM concentration tim e-series in order to remove the
tid al signal. A polynom ial de-trending o f the low-pass filte re d data was then accom plished to filte r
o ut the spring-neap signal. A peak detection fu nctio n o f these processed data allowed eventually
cataloguing the extrem e SPM concentrations and relating them to storm events and wave system
data. The m ethod used allows identifying and understanding the co n tro llin g factors, i.e. influence o f
wave systems on the SPM concentration. It is a prom ising m ethod th a t could also be used to analyse
and classify the surface SPM concentration maps derived fro m polar o rb itin g o r geo-stationary
satellites.
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How do marine nematodes cope w ith extrem e tem peratures and
fluctuations?
Vafeiadou Anna-M aria12, Chariton C h in tiro g lo u 2 and Tom M oens1
1 Marine Biology Section, Ghent University, Krijgslaan 281 /S8, 9000 Ghent, Belgium
E-mail: am.vafeiadou@ qmail.com
2 Biology Departm ent, A risto tle U niversity o f Thessaloniki, 54124 Thessaloniki, Greece
Increased tem perature flu ctu a tio n s and m axim a have been reported the last decades as main
consequences o f global clim ate change. In inte rtid a l areas, the com bination o f episodically elevated
w ater tem perature and short-term exposure to high air tem perature at low tide may exceed the
tolerance o f some organism s, causing local extinctio ns. A lth ou g h organism s develop p la sticity
tow ards stress, extrem e change o f the environm ental co nd itio ns can eventually a lter population
dynamics. Marine nematodes are the m ost abundant benthic organism s, and due to th e ir short life
span, th ey are an excellent taxon fo r the investigation o f benthic responses to such stress
conditions. T he ir response w ill be exam ined at m ultiple levels: from individuals to populations and
com m unities, including also interactions among species a n d /o r tro p h ic levels. Specifically, the
effects o f short-term (daily/w eekly) tem perature flu ctua tion s on nematode populations and
individuals, w ith in the same or between adjacent tro p h ic levels w ill be exam ined. In a dd itio n, the
effects o f tem perature changes on the ecology o f marine nematodes, and in particular th e ir
behavior, w ill be investigated w ith in vivo m icrocosm experim ents. Specifically, we focus on the
m oving a b ility and the food selectivity o f three closely related nematode species which d iffe r in th e ir
tolerance to tem perature flu ctu a tio n s and extrem es to detect any effects due to flu ctu a tin g
tem perature.
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Microplastics... one league under the sea*!
Van Cauwenberghe Lisbeth', Ann Vanreusel2, Jan Mees23 and Colin R. Janssen'
' Laboratory o f Environm ental T o xico lo g y and A quatic Ecology, Ghent University, Jozef Plateaustraat
22, B-9000 Ghent, Belgium
E-mail: Lisbeth.VanCauwenberqhe@ UGent.be
2 Marine Biology Research Group, Biology Departm ent, Ghent University, Krijgslaan 281/S8, B-9000
Ghent, Belgium
3 Flanders Marine Institute (VLIZ), InnovOcean site, Wandelaarkaai 7, B-8400 Oostende, Belgium
M icroplastics are small plastic particles (<1 mm) o rig in a tin g fro m the degradation o f larger plastic
debris. These m icroplastics have been accum ulating in the marine environm ent fo r decades and
have been detected th ro u g h o u t the w ater colum n and in s u b litto ra l and beach sedim ents w orldw ide.
However, up to now, it has never been established w hether m icroplastic presence in sedim ents is
lim ited to accum ulation hot spots such as the continental shelf, or w hether they are also present in
deep-sea sedim ents. Here we show, fo r the firs t tim e ever, th a t m icroplastics have indeed reached
the m ost remote o f marine environm ents: the deep sea.
Sediment o rig in a tin g from several locations in the A tla n tic Ocean and Mediterranean Sea were
investigated fo r the presence o f m icroplastics. The sam pling stations were located in the A tla ntic
sector o f the Southern Sea, on the Porcupine Abyssal Plain (N orthern A tla n tic Ocean), in the distal
lobe o f the Congo Canyon (G ulf o f Guinea, South A tla n tic Ocean) and in the Nile Deep Sea Fan in the
Eastern Mediterranean. These locations range in depth from 1100 to 5000 metres.
M icroplastics sized in the m icrom eter range (75 - 161pm ) were detected in the to p centim etre o f
the sedim ent at three o f the fo u r locations. Based on the (lim ited) surface sampled it can be
te ntative ly concluded th a t in /o n the seafloor o f the deep sea, m icroplastics can reach an average
abundance o f 0.5 m icroplastics per 25cm 2.
Our results dem onstrate th a t m icroplastic p o llu tio n is present in the to p sedim ent layer o f the deepsea floor. However, no conclusive statem ents can be made on how these m icroscopic particles were
transported to the seafloor. Yet, th e ir presence indicates th a t m icroplastics have spread th ro u g h o u t
the w o rld ’s seas and oceans, and into the remote and largely unknown deep sea.
* This title refers to Jules Verne’s novel ‘T w enty Thousand Leagues Under the Sea’ (1 870), w ith one
League corresponding to a pp ro xim a tely 5.5km .
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M icroplastic on our plate, also in ou r shops.
Van Cauwenberghe Lisbeth, M ichiei Claessens and Colin R. Janssen
Laboratory o f Environm ental T oxico lo g y and A quatic Ecology, Ghent University, Jozef Plateaustraat
22, B-9000 Ghent, Belgium
E-mail: Lisbeth.VanCauwenberqhe@ UGent.be
M icroplastics are present th ro u g h o u t the marine environm ent, and ingestion o f these small (<1 mm)
plastic particles has been dem onstrated repeatedly in a laboratory setting fo r a wide array o f marine
(invertebrate) organism s. However, as the exposure concentrations o f m icroplastics in these types
o f experim ents are much higher (over a thousand tim es higher) than any reported field
concentration, it is d iffic u lt to assess the relevance o f these results fo r natural environm ents.
Therefore, we assessed the presence o f m icroplastics in tw o bivalve species living in natural
conditions: both field collected and cultured individuals o f M ytilus edulis, and farm ed Crassostrea
gigas were investigated.
Part o f the organism s (all fie ld collected M. edulis (N=30), and h alf o f the cultured M. edulis (N=36)
and C. gigas (N=10)) were subjected to a g ut depuration to allow them to clear th e ir gut. The other
organism s were analysed fo r m icroplastics w ith o u t p rior treatm ent. To exam ine m icroplastic
presence in the animals, the soft tissues were acid digested using H N 0 3.
Small num bers o f m icroplastics were recovered fro m the tissue o f the species under investigation.
In field collected M. edulis the average m icroplastic load (post-depuration) was 0.20 ± 0.30 particles
per gram o f soft tissue. In cultured M. edulis m icroplastic load (pre-depuration) was 0.36 ± 0.07
particles per gram o f soft tissue. A fte r the depuration period, o nly 0.24 ± 0.07 particles g 1 were
encountered. The same trend was observed in C. gigas: w ith o u t depuration on average 0.47 ± 0 .1 6
particles g 1 were present in the animals, while m icroplastic concentrations decreased to an average
o f 0.35 ± 0.05 particles per gram so ft tissue a fte r depuration. It is not surprising th a t the
m icroplastic load o f cultured animals resembles th a t o f field collected anim als since th ey are
cultured in natural conditions. As a result these filte r feeding organism s are exposed to any
p o llu ta n t present in the seawater, including m icroplastics, in the same way as th e ir wild
counterparts.
A lthough it is now established th a t mussels and oysters contain m icroplastics, th is is the fis t report
so fa r on m icroplastics in fo o d stu ffs. C urrently, o nly a pre lim ina ry die ta ry exposure could be
estim ated. The hazard posed by m icroplastics needs to be established th ro ug h in-depth
to xico lo g ica l studies. Due to a lack o f dedicated studies, the co m p le xity o f estim ating particle
to x ic ity hinders a comprehensive assessment o f the hazards associated w ith m icroplastics.
Estim ations o f the potential risks fo r human health posed by m icroplastics in food stuffs is not
possible.
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O p tim iz in g the establishm ent o f inland brackish marshlands: firs t
results o f a large-scale e xp erim en t and a survey on the invertebrate
c o m m u n ity
Van de M eutter Frank, Ralf Gyselings and Erika Van den Bergh
Research Institute fo r nature and forest, Research Group Ecosystem D iversity
Kliniekstraat 25,1070 Brussels, Belgium
E-mail: Frank.Vandem eutter@ inbo.be
Brackish m arshlands are exceptional habitats confined to places where brackish groundw ater
surfaces. The area o f brackish m arshland has shrunken dram atically and a considerable am ount o f
the rem aining area is under th re at by contin uing harbour expansions. C urrently, the loss o f
brackish m arshlands w ith in the NATURA 2000 netw ork needs to be compensated fo llo w in g EU
legislation. The Institute fo r Nature and Forest Research (INBO) was asked to compare d iffe re n t
scenarios fo r establishing successful com pensation.
In a large o u td o o r e xperim ent on fo u r locations (Kieldrecht (2), Oudenburg, Zeebrugge), we
compare the establishm ent o f brackish m arshland vegetation on bare soil between twelve
com binations (700 plots) o f translocation treatm ents (transfer o f sods, seeds o f focal species only,
hay, no transfer) fu lly crossed w ith three m anagem ent treatm ents (m owing, grazing by cows, no
managem ent) over three grow ing seasons. The e xperim ental units are 1 m2 square plots in which we
m o n ito r plant cover, plant reproduction and plant height (average and m axim um ). Evaluation o f
successful ecosystem com pensation is pre fere ntia lly based on more than vegetation alone.
Invertebrates are a prime com ponent o f bio dive rsity hence very suitable fo r evaluating
com pensation success, yet very little is known on invertebrate com m unities o f brackish m arshland.
We choose to build a basis dataset o f current bio dive rsity o f invertebrates in brackish m arshlands in
Flanders fo r later evaluation assessment. We therefore designed a survey applying a set o f
standardized sam pling devices ta rg etin g d iffe re n t com ponents o f the invertebrate com m unity:
pitfa ll traps (ground-dw elling species), Malaise traps (flying species) and coloured pan traps (m ainly
flying species). A t present, fo u r brackish m arshland areas have been sampled: Putten Weiden
(Kieldrecht, 2012), M onnikenwerve (Lissewege, 2012), ‘t Pompje (Oudenburg, 2012), Uitkerkse
polder (Uitkerke, 2013).
We here present the firs t results o f the e xperim ental study and the invertebrate survey. Results o f
the e xperim ental study are particula rly prem ature, a fte r ju s t one grow ing season. A ll three true
translocation m ethods increase the co lonization o f plots by typical saltm arsh plant species. Note
th a t co lonization not necessarily im plies establishm ent: w ith the closing o f vegetation, focal plant
species w ill experience increasing com p etitio n w ith the many o the r species th a t colonized the plots.
The invertebrate survey samples are c u rren tly processed. Prelim inary analyses suggest large
d iffe re n tia tio n among sites, even w ith in one area. Typical brackish m arshland species appear largely
confined to sites where a constant supply o f brackish w ater to the to p so il is available. Future
analyses w ill dig deeper into the relationship w ith local soil sa lin ity (measured by rhizons) and into
the question whereas the invertebrate co m m un ity o f inland brackish m arshlands is fu lly nested in
th a t o f tid a l saltmarshes, or w hether inland brackish m arshlands harbor a unique com ponent o f
to ta l brackish m arshland biodiversity.
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W orking to g e th e r on innovative m o n ito rin g strategies: adapting to
nature, huge demands and grand challenges
Van Lancker Vera14, Matthias Baeyela, Frederic Franckenla, Dries Van den Eyndela, D im itris
Evangelinos2, Ilse De Mesellb, Francis K erckhoflb, Reinhilde Van den Branden"1and Lieven N audtslb
1 Royal Belgian Institute o f Natural Sciences
“Operational D irectorate Natural Environment, Gulledelle 100, B-1200 Brussels, Belgium
bO perational Directorate Natural Environm ent, 3de en 23ste Linieregim entsplein, B-8400
Oostende, Belgium
E-mail: vera.vanlancker@ mumm.ac.be
2 MSc Marine and Lacustrine Science and Management (Oceans & Lakes), Pleinlaan 2,
B-1050 Brussels, Belgium
Socio-economic dem ands fo r marine aggregate resources have increased at an unprecedented pace.
For the A tla n tic region, hundreds o f m illion s m 3 o f offshore sand and gravel have been extracted fo r
coastal maintenance, harbour extensions and onshore industrial use. Still, we are facing grand
challenges, fo r which aggregate demands w ill be even higher. First, increasing volum es o f
nourishm ent sand are needed as accelerating sea-level rise w ill leave our coastlines ever more
vulnerable. Secondly, vast quantities o f sand and gravel w ill have to be extracted to realize the large
infra structu ra l w orks th a t are the key com ponents o f many visions on coastal zone and offshore
developm ent. Meanwhile, nature protection is increasing as well, and appropriate assessments are
needed o f the environm ental impacts.
The fa r offshore H inder Banks are targeted fo r e x p lo ita tio n o f huge quantities o f sand, m ainly fo r
coastal defence w orks. Here, up to to 2.9 m illion m 3 can be taken over 3 m onths, w ith a m axim um
o f 35 m illion m 3 over a period o f 10 years. Large vessels can be used e xtra cting 1 2500m 3 per run.
Present-day yearly extraction levels recently surpassed 3 m illion m3, the m ajority o f which was
extracted w ith vessels o f 1500m 3. South o f the H inder Banks concession, a H abitat Directive area is
present, hosting ecologically valuable gravel beds. For these, it is critical to assess the effect o f
m ultiple and freq ue n t depositions from dredging-induced sedim ent plumes.
How w ill natu re react?
We anticipated w ith a m on itoring strategy, ta ilo re d fo r assessing the im portance and e xten t o f
perturbations th a t are created by the e xtra ction activities. Our m on itoring design is focussed on
hydrodynam ics and sedim ent tra n sp o rt w ith feedback loops between both m odelling and field
studies. Main targets are assessing changes in seafloor in te g rity and hydrographic conditions, tw o
key descriptors o f marine environm ental status w ithin Europe’s Marine Strategy Framework
Directive.
State-of-the-art instru m e ntatio n (from RV Belgica) is used, to measure the 3D cu rren t structure,
tu rb id ity , depth, backscatter and particle size o f the m aterial in the w ater colum n, both in-situ and
w hilst sailing transects over the sandbanks. In the Habitat Directive Area, gravel bed in te g rity (i.e.,
epifauna; sand/gravel ratio; patchiness) is measured as well. Most innovatively, an autonom ous
underw ater vehicle was deployed (Wave Glider, Liquid Robotics), resulting in 24 days o f current and
tu rb id ity data.
From a firs t data-m odel integration, and analyses against hydro-m eteorological databases, main
results show: (1) high spatial and tem poral va ria b ility o f tu rb id ity , unexpected in the so-called
‘clear’ w aters o f the H inder Banks; (2) im p o rta n t resuspension by waves, regardless the area being
considered as ‘deep’; (3) spreading and deposition o f sedim ent plumes; and (4) com petitiveness o f
ebb and flood, m eaning th a t the potential fo r sedim ent deposition to the south is high. Plume
dispersion mechanisms and pathways are now estim ated and modelled.
Data w ill be integrated w ith results from the m orphological and biological m on itoring , respectively
carried o ut by the C ontinental Shelf Service o f FPS Economy and the Institute fo r A g ric u ltu ra l and
Fisheries Research. Together, te m p ora l and spatial patterns, scale and processes can be resolved
and interlinked w ith pressures and system vulnerability.
-110-
Exploring ou r marine geological resources in the fifth dim ension:
A b o u t 3D voxels, 4D im pact models and uncertainty
Van Lancker Vera', Lies De M ol2, Guy De T ré 3, Denise M aljers4, Tine Missiaen3, Jan Stafleu4, Dries Van
den Eynde1, and Sytze van Heteren4
1 O perational Directorate Natural Environm ent, Royal Belgian Institute o f Natural Sciences,
Gulledelle 100, B-1200 Brussels, Belgium
E-mail: vera.vanlancker@ mumm.ac.be
2 C ontinental Shelf Service, SMEs, Self-Employed and Energy, Federal Public Service Economy,
Koning A lb e rt 11-laan 16, B-1000 Brussels, Belgium
3 Database, Docum ent and C ontent Management, D epartm ent o f Telecom m unications and
Inform ation Processing, Faculty o f Engineering, Ghent University, St.-Pietersnieuwstraat 41,
B-9000 Gent, Belgium
4 TNO - Geological Survey o f the Netherlands, Princetonlaan 6, 3584CB Utrecht, the Netherlands
3 Renard Centre o f Marine Geology, D epartm ent o f Geology, Ghent University, Faculty o f Sciences,
Krijgslaan 281, B-9000 Gent, Belgium
Mineral and geological resources such as sand and gravel, ores and hydrocarbons can be
considered to be non-renewable on tim e scales relevant fo r decision makers. Once exhausted by
humans, th e y are not replenished rapidly enough by nature, m eaning th a t tru ly sustainable
managem ent o f these invaluable and sought-after resources is not possible. Using them w isely and
sparingly requires a th orou g h and careful balancing o f available q u a n tity and q u a lity versus rapidly
changing societal and econom ical needs. The need fo r such an approach is recognized in the EU’s
Raw Materials Initiative, which h ig hligh ts the o p tim iza tio n o f the geological knowledge base as a
key elem ent in ensuring enduring supplies fro m w ith in the EU borders. Com prehensive knowledge
on the d istrib u tio n , com position and dynamics o f geological resources therefore is critical fo r
developing long-term strategies fo r resource use in our changing world.
To help ensure the o ptim al use o f fin ite q uantities o f sand and gravel in the Belgian and southern
Dutch parts o f the North Sea, the new Belspo Brain-be project TILES w ill develop cross-border and
integrated strategies fo r th e ir long-term extraction. TILES has the a m bition of:
Developing a decision support system (DSS) fo r resource use. This DSS contains tools th a t link 3D
geological models, knowledge and concepts, providing inform a tion on present-day resource
quantities and d istrib u tio n , to num erical m odels o f extraction-related environm ental im pact th ro ug h
tim e. T ogether they q u a n tify natural and man-made boundary conditions and changes to define
e xp lo ita tio n thresholds th a t safeguard su stain ab ility on a m ulti-decadal tim e scale. These
thresholds need to be respected to ensure th a t geom orphological and habitat recovery from
perturbations is rapid and secure, a prerequisite stated in Europe’s Marine Strategy Framework
Directive, the environm ental p illa r o f Europe’s M aritim e Policy.
Providing long-term adaptive m anagem ent strategies th a t have generic value and can be used fo r all
non-hydrocarbon geological resources in the marine environm ent, locally and more globally.
Proposing legally binding measures to o ptim ize and m axim ize long-term e x p lo ita tio n o f aggregate
resources w ith in sustainable environm ental lim its. These proposed measures feed into policy and
associated m on itoring plans th a t are periodically evaluated and adapted (e.g. Marine Spatial
Planning and the Marine Strategy Framework Directive).
Extensive analyses o f data- and interpolation-related uncertainties, and o f the propagation o f these
uncertainties in data products such as maps and GIS layers, fo rm the backbone o f the DSS. This is a
necessary step in producing data products w ith confidence lim its, and critical to detecting ‘ tr u e ’
seabed changes in environm ental m on ito rin g . Using a dedicated subsurface viewer, a suite o f data
products w ill be viewable online. They can be extracted on demand from an underlying voxel (3D
pixel) model. Each voxel w ill be assigned w ith values fo r geological, environm ental and decisionrelated parameters, including uncertainty. The fle xib le 3D interaction and querying, enabled by
TILES, w ill be invaluable fo r professionals, but also fo r the public at large and fo r students in
particular. It w ill herald a new age in assessing cross-border impacts o f marine e xp lo ita tio n
activities.
- I l l -
Did sedim ent accum ulation o f 21 OPb and 1 37Cs in mangrove forests
o f Vietnam (Ca Mau Peninsula) respond to sea level rise?
Van Tran T h i123, Katrien Q u isth o u d t2, Hai Phan Son4, Farid D ahdouh-G uebas'2 and Nico Koedam'
' Laboratory o f Plant Biology and Nature Management, Vrije U niversiteit Brussel
Pleinlaan, 2, B-1050 Brussels, Belgium
E-mail: ttra n l @vub.ac.be
2 Laboratory o f Systems Ecology and Resource Management, Université Libre de Bruxelles
Av. F. D. Roosevelt, 50, B-1050, Brussels, Belgium
3 Center fo r HydroM et and Environm ent Consultancy, Institute o f M eteorology, H ydrology and
Environm ent, 2 3 /6 2 Nguyen Chi Thanh, Hanoi, Vietnam
4 Center fo r Environm ent Research and M onitoring, Da Lat Nuclear Research Institute
No. 1 Nguyen Tu Luc, Da Lat city, Lam Dong province, Vietnam
Mangroves are highly productive forests b u ilt by a small g ro up o f trees and shrubs th a t have
adapted to survive in the harsh interface between land and sea. Ecologically, th ey intercept landderived n utrients and suspended m atter. Geologically, mangrove forests serve as sedim ent sinks by
the long-lasting accum ulation o f sedim ent trapped by th e ir root system. The continued provision o f
these fu n ctio n s is dependent on the capacity o f mangroves to adapt to projected rates o f sea level
rise (Mcivor e t al., 201 3).
One o f the m ost potential m ethods fo r estim ating sedim entation rate on a tim e scale o f 100-150
years is by means o f 2l0Pb. It has been popular in e stim ating the sedim entation rate o f mangrove
ecosystems. In com m on practice, l37Cs is used as an independent tracer to ve rify 2l0Pb m ethod (Lu
and M atsum oto, 2005). Ca Mau Peninsula is located at the southern tip o f Vietnam , on the Mekong
River delta th a t is one o f the m ost low-lying river deltas in Vietnam . In a rapid assessment, CarewReid (2007) stated th a t 186km 2 o f fo re st and natural vegetation in Ca Mau province w ill be affected
by lm sea level rise inundation. Recently, the M inistry o f Natural Resources and Environm ent
predicted th a t by the end o f the 21st century, average sea level in the study area is projected to rise
59cm -75cm and 62cm -82cm along the East Sea and the G ulf o f Thailand respectively (MONRE,
2012). While rapid assessment is useful fo r applying precautionary principle when faced w ith
uncertainties on the precise location and nature o f clim ate change impacts, historical studies are
always valuable and as baselines fo r long-term planning and managem ent. In Vietnam, the response
o f m angrove sedim entation to historical sea level rise has not been exam ined although 2l0Pb
accretion has been studied in the soil cores o f m angrove forests in the Red River delta.
In th is study, five 2m-cores were sampled in dense mangrove forests at both sides o f the East Sea
and G ulf o f Thailand in Ca Mau Peninsula. These were used to exam ine w hether sedim ent
accum ulation o f 2l0Pb and l37Cs in mangrove forests responded to historical sea level rise. Then,
mangrove sedim entation was predicted in the co nte xt o f projected sea level rise scenarios caused
by global w arm ing. The results are valuable to assess im pacts o f sea level rise to m angrove forest
and integrated in advanced planning fo r coastal zone m anagem ent in Ca Mau.
References
Carew-ReidJ. 2007. Rapid assessment o f the e xten t and im pact o f sea level rise in Viet Nam.
Climate Change Discussion Paper 1, International Centre fo r Environm ental Management,
Brisbane, Australia.
Lu X. and E. M atsum oto. 2005. Recent sedim entation rates derived fro m 2l0Pb and l37Cs m ethods in
Ise Bay, Japan. Estuarine, Coastal and Shelf Science 6 5 :8 3 -9 3 .
Mcivor A., T. Spencer, I. M öller M. Spalding. 201 3. The response o f m angrove soil surface elevation
to sea level rise. Natural Coastal Protection Series Report 3. C am bridge Coastal Research Unit
W orking Paper 42. Published by The Nature Conservancy and Wetlands International. 59p. ISSN
2050-7941. URL: h ttp ://co astalresilience.orq/science/m anqroves/surface-elevation-and-sealevel-rise
MONRE (M in istry o f Natural Resources and Environment). 201 2. Clim ate change, sea level rise
scenarios fo r Vietnam . Hanoi, Vietnam . 23p.
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Ocean acidification affects the benthic nitrogen cycle in coastal
sediments: evidence from the Belgian Part o f the North Sea
Vanaverbeke Jan1, Ulrike Braeckman', Cari Van Colen', Katja G u ilin i', D irk Van Gansbeke', Karline
Soeteaert2 and Magda Vincx'
1 Marine Biology Research Group, Ghent University, Krijgslaan 281/S8, B-9000 Gent, Belgium
E-mail: ian.vanaverbeke@ uqent.be
2 D epartm ent o f Ecosystem Studies, Netherlands Institute fo r Sea Research, PO Box 140, 4400 AC
Yerseke, the Netherlands
Research so fa r provided little evidence th a t benthic ecosystem fu n c tio n in g is affected by ocean
acidification under realistic clim ate scenarios (pH decrease o f 0.3). Therefore, ocean acidification is
considered a process acting in the w ater colum n, w ith little to no direct effect on benthic ecosystem
fu n ctio n in g . However, m ost o f these investigations did not cover d iffe re n t sedim ent types and
possible seasonal effects. The scarce inform a tion is available from relatively fine-grained sediments,
while the e ffe ct o f ocean acidification on permeable coarse sediments, covering the b ulk o f coastal
sediments, remain virtu a lly unexplored. We investigated w hether a pH decrease o f 0.3 affects
sedim ent co m m un ity oxygen consum ption (SCOC), n u trie n t exchange, estim ated n itrific a tio n rates
and a lka lin ity flu xes in coastal permeable and fine sandy sediments. As benthic ecosystem
fu n ctio n in g is largely affected by the tim in g o f phytoplankton bloom deposition, we repeated our
incubations before, durin g and a fte r bloom deposition. We observed a lower SCOC in both sedim ent
types w ith a decreased pH compared to am bient pH in February and A pril. This suggests th a t
benthic oxygen consum ing processes (such as n itrific a tio n ) m ig ht be hampered at lower pH, which
is indeed corroborated by lower estim ated n itrific a tio n rates in these treatm ents. In addition,
acidified sedim ents displayed more erratic (zero and negative) estim ated n itrific a tio n rates. This
suggests th a t the acidified benthic ecosystem is o u t o f steady state, and h ig h lig h ts the need fo r
long-term (> 14 days) experim ents to measure the effect o f ocean acidification on benthic nitrogen
cycling. Structural and fu nctio na l characteristics o f m acrofauna were not affected by pH. Whereas
drastic changes in pH affect benthic nitrogen cycling th ro ug h altered m acrofauna activity, we
hypothesize th a t a realistic decrease in pH (-0.3) affects benthic nitrogen cycling th ro u g h small
changes in the m icrobial com m unity.
-113-
Larval dispersal and ju ven ile dynamics o f flatfish in the Southern
North Sea
Vanden Bavière Andreas', Johan Robbens1, Filip V olckaert2, Sophie Delerue-Ricard2, Geneviève
Lacroix3 and Léo Barbut3
1 Institute fo r A g ricu ltu ra l and Fisheries Research, A nkerstraat 1, B-8400 Ostend, Belgium
E-mail: andreas.vandenbaviere@ ilvo.vlaanderen.be
2 Laboratory o f Biodiversity and Evolutionary Genomics, Katholieke U niversiteit Leuven,
Ch. D eberiotstraat 32, B-3000 Leuven, Belgium
3 O perational D irectorate Natural Environm ent (form erly MUMM), Royal Belgian Institute o f Natural
Sciences, Gulledelle 100, B-1200 Brussels, Belgium
Marine populations display some o f the m ost extrem e patterns o f spatial and tem poral
heterogeneity in dem ographic factors. Over the past few decades, many marine fisheries have
declined or even collapsed. This is in large part, due to clim ate change and d etrim ental
anthropogenic influences (e.g. habitat degradation and overfishing). Due to a hig hly com plex
optim al w indow between biological needs and favorable environm ental factors, marine species are
very susceptible to natural p erturbations. This leads to unpredictable reproductive success, high
m o rta lity and obscure population delineations. Preventing a com plete collapse o ffis h stock requires
a th orou g h knowledge o f the recruitm ent dynamics. With the B-FishConnect project we w ant to
disentangle the physical and biological factors influencing dispersal and recruitm en t in fla tfish.
W ithin the project, we w ill focus on fo u r com m ercially im p o rta n t fla tfis h species in the North Sea:
sole, plaice, tu rb o t and brill. To q u a n tify the role o f physical and biological factors on the
population dynamics, a com bination o f hydrodynam ic and dem ographic-genetic models w ill be
applied. The o u tp u t o f these m odels w ill be compared to em pirical field data. The focus o f this
project w ill be on the post-larval and juve nile stages o f fla tfis h . Inform ation on the spatial-tem poral
dynamics o f larvae and juveniles w ill be gathered by an intense sam pling campaign along the coast
as well as on sea. A d d itio n a l inform a tion w ill be obtained th ro ug h historical datasets. The larval
dispersal history w ill be inferred by analysing the o to lith m icrostructure o f juvenile fla tfis h . The
effect o f the larval h istory and local habitat characteristics on the fu tu re survival and co ndition o f
juvenile fla tfish w ill be investigated. This w ill be accom plished by using biom arkers and co ndition
indices. The derived inform a tion on life -h isto ry traits, population structure and spatio-tem poral
dynamics w ill be used to validate the dispersal m odels (Lacroix et al., 2013). In a later phase this
w ill allow us to te st d iffe re n t ecological hypotheses and to assess the im pact o f various scenarios
related to clim ate change and human im pact on fla tfis h in the North Sea. C onsequently these data
w ill be vital fo r fisheries and conservation management.
References
Lacroix G., G.E. Maes, L.J. Bolle and F.A.M. Volckaert. 2013. M odelling dispersal dynamics o f the
early life stages o f a marine fla tfis h (Solea solea L.). Journal o f Sea Research 84:1 3-25.
-114-
Beach no urishm ent and the im pact on Natura 2000
Vanden Eede Sarah1, Michiei Sm its', Annelies Bolle', H endrik Schoukens2, Tina M ertens3
and Steven Degraer4
' International Marine and Dredging C onsultants (IMDC)
C oveliersstraat 15, 2600 Berchem
E-mail: sarah.vanden.eede@imdc.be
2 D epartm ent o f Public International Law, Ghent U niversity
U niversiteitstraat 4, 9000 Gent
3 Flanders Marine Institute
InnovOcean site, Wandelaarkaai 7, 8400 Oostende
4 OD/DO N atuu rlijk M ilie u /M ilie u x Naturels, Marine Ecosystem Management Section
Royal Belgian Institute o f Natural Sciences, GulledeIle 100, 1200 Brussels
The Belgian coastline is a dynam ic environm ent where currents, waves and w ind interact w ith the
natural coastal defence system o f beaches and dunes. In theory, the coastline should w ithstand a
1000 year storm event, but at its weakest links o nly a 100 year protection level is cu rren tly reached.
In the past so-called ‘ h ard ’ infrastructure (dykes, quay walls and groins) was constructed to protect
the land from the im pact o f the sea. Pending the realization o f the ‘ Master Plan fo r Coastal Safety’ ,
the weakest beaches are annually m aintained w ith ‘s o ft’ measures, e.g. beach nourishm ents.
Belgian beaches contain fine sand (200-250pm ), whereas fro m a geotechnical p oint o f view the
nourished sand ideally has a grain size o f at least 300pm creating more stable beaches. However,
the ecological effects o f beach n ourishm ent can be d ire c tly related to changes in grain size
(Speybroeck et al., 2006). Im pact research focuses on m acrobenthos, the seafloor inhabiting
benthic fo rm s larger than one m illim eter, as these organism s play a key role in the w ider beach
ecosystem. Locally, strong negative im pact effects are expected during and im m ediately fo llo w in g
nourishm ent since the chances o f survival o f the original beach fauna and flo ra are alm ost zero
(Harte e t al., 2002; Speybroeck e t al., 2004). The speed and degree o f ecological recovery largely
depend on the physical characteristics o f the beach habitat. M acrobenthic organism s tolerate only
small m odifications in beach slope and sedim ent grain size (150-300pm ). In general, phased
nourishm ent w ith natural sedim ent and beach slope during w in te r are recom m ended (Van Tom m e,
201 3; Vanden Eede, 201 3), urging fo r an o p tim iz a tio n o f the technical nourishm ent aspects.
When considering beach nourishm ent in the neighbourhood o f European protected sites, one m ust
take into account the strict regulatory fram e w o rk w ith respect to Natura 2000, which is included in
the Habitats Directive (Directive 92/43/EEC). In particular, article 6, §§3-4 contains a developm ent
regime, setting o ut the criteria under which plans and projects w ith possible negative effects on
Natura 2000 may or may not be allowed. A precautionary approach is required when assessing the
possible effects o f beach nourishm ent. In the Flemish Region th is fram ew ork has been im plem ented
in the Nature Conservation Decree in 2002, w hile the Royal Decree o f 14 October 2005 contains the
federal im plem entation fo r the Belgian part o f the North Sea. A lth ou g h the requirem ents o f Article
6, §§3-4 o f the Habitats Directive are quite straig htforw ard, the application on beach nourishm ent
proved to be quite burdensome the past years, p a rtia lly due to the incorrect im plem entation o f the
Habitats Directive in the Flemish legislation (Schoukens e t al., 2007). The d iffic u lt and som etim es
very incoherent application o f the rules o f nature conservation on beach nourishm ent, illustrates the
need fo r a more coherent legal fram e w o rk w ith an ecosystem based strategic approach, allow ing fo r
onsite m itig atio n and or offsite com pensation.
To investigate w hether intertida l beach nourishm ent has a s ig n ific a n t negative im pact on the global
conservation status o f nearby Natura 2000 areas, a fo u rfo ld assessment approach was created and
follow ed in some Belgian case studies (IMDC, 2011 ; 201 2).
References
Harte M., P.M. H u n tje sJ.M . M ulder S. and E.W. Raadschelders. 2002. Zandsuppleties en Europese
rich tlijn e n: R ijksin stituu t voor Kust en Zee/RIKZ. M inisterie van Verkeer en Waterstaat.
IMDC. 2011. Referentiekader habitattype 1140 in het kader van de ecologische o ptim alisatie van het
Geïntegreerd Kustveiligheidsplan. I/NO/1 1310/1 1.259/MSM. In opdracht van A fdeling Kust.
IMDC. 2012. Geïntegreerd Kustveiligheidsplan. Passende beoordeling Raversijde-Mariakerke.
l/RA/1 1310/1 2057/M SM . In opdracht van A fdeling Kust.
- 115 -
Schoukens H., P. De Smedt and A. Cliquet. 2007. The Im plem entation o f the Habitats Directive in
Belgium (Flanders): back to the O rigin o f Species?. Journal fo r European Environm ental &
Planning Law 2007:1 27-1 38.
Speybroeck J., D. Bonte, W. Courtens, T. Gheskiere P. G rootaert, J.P. Maelfait, M. Mathys, S. Provoost,
K. Sabbe, E. Stienen., V. Van Lancker, M. Vincx and S. Degraer. 2004. Studie over de impact
van zandsuppleties op het ecosysteem - fase 1, dossiernum m er 202.165. M inisterie van de
Vlaamse Gemeenschap, D epartem ent Leefmilieu en Infrastructuur, Agentschap voor
Maritiem e D ienstverlening en Kust, A fde lin g Kust: 201 p.
Speybroeck J., D. Bonte, P. G rootaert, J.P. Maelfait, E. Stienen, V. Vandomm e, N. Vanermen, M. Vincx,
S. Degraer. 2006. Studie over de im pact van zandsuppleties op het ecosysteem - fase 2,
dossiernum m er 204.295. M inisterie van de Vlaamse Gemeenschap, Departem ent Leefmilieu
en Infrastructuur, Agentschap vo or M aritiem e D ienstverlening en Kust, A fde lin g Kust: 11 8p.
Vanden Eede S. 2013. Im pact o f beach nourishm ent on coastal ecosystems w ith recom m endations
fo r coastal policy in Belgium. Ghent U niversity (UGent): 301 p.
Van Tom m e J. 2013. Biotic interactions w ithin sandy beach ecosystems, w ith im plications fo r an
ecologically-sound beach nourishm ent. (Biotische interactie s in zandstrandecosystem en,
m et z ijn im plicaties voor ecologisch onderbouwde strandopspuitingen). Ghent U niversity
(UGent): 176p.
-116-
Judging je llyfish : factors influencing the perception on je lly fish and
th e ir blooms
Vandendriessche Sofie1, Lies Vansteenbrugge' 2, Kris Hostens1 and Hannelore M aelfait3
1 Institute fo r A g ricu ltu ra l and Fisheries Research (ILVO), A quatic Environm ent and Quality,
Bio-environm ental Research, A nkerstraat 1, B-8400 Oostende, Belgium
E-mail: Sofie.Vandendriessche@ ilvo.vlaanderen.be
2 Marine Biology Section, Biology Departm ent, Ghent University, Krijgslaan 281, S8, B-9000 Gent,
Belgium
3 C oordination Centre fo r Integrated Coastal Zone Management, Wandelaarkaai 7,
B-8400 Oostende, Belgium
During the last decades, the num ber o f reports on invasions and bloom s o f je lly fis h has increased,
both in the scientific literature and the general media. As extended tim e series are lacking, no
clarity exists on w hether the gelatinous Zooplankton is really increasing or w hether th is is ju s t a
perception. Moreover, it is not clear how this ‘j e llific a tio n ’ is perceived by the public and how the
media influences th is perception. Public perception is a key driver in policy decisions, e.g. on
coastal zone governance and research fu nd ing . Therefore, it is useful to investigate the v a ria b ility in
public perception and the relationship between the m edia and the public perception. For th is case
study we perform ed a questionnaire survey and a th orou g h media search regarding the perception
on je llyfish and the consequences o f je lly fis h bloom s along the Belgian coast. The results indicate
th a t public perception is only p artly driven by the press when it comes to je lly fis h . Personal
experience seems to be an equally im p o rta n t driver. A d ditio na lly, a substantial variation exists in
je lly fis h perception illustrated by the differences in perception between beach to u rists and divers.
The lack o f knowledge about d iffe re n t je lly fis h species (e.g. harmless vs. stinging species) turned
o ut to be a key issue in the w ider public perception. Both the v a ria b ility in perception and the
lim ited species knowledge should be taken into account when incorporating the present and future
je llific a tio n problem s in integrated coastal zone management. A t firs t instance, the perception
surveys should be extended to all users o f the sea and the coastal zone, which are e ither d ire c tly or
ind ire ctly affected by the presence o f je lly fis h . This can lead to o p p o rtu n itie s fo r a broad
cooperation between scientists, policym akers and public parties in the fo rm o f ‘citizen science’.
Secondly, m anagem ent actions concerning je lly fis h increases should include the provision o f
species-specific inform ation, fo r exam ple by d is trib u tin g leaflets and p uttin g up w arning boards on
the beach. This w ill likely result in a better acceptance/know ledge o f je lly fis h and je llific a tio n , a
better com m unication between scientists and the public, and a higher q u a lity o f data in citizen
science program s. A lth ou g h com m unication about je lly fis h is m ainly a coping strategy, it can also
co ntribu te to the developm ent and im plem entation o f m itig a tin g strategies. Given the
transboundary nature o f the problem , such strategies should be im plem ented on an international
level and should address all underlying causes, as was indicated by the survey results.
-117-
Occurrence o f m icroplastics in brown shrim p on the Belgian part of
the North Sea
Vandermeersch G.1, L. Devriese', K. Bekaert1, S. Vandendriessche2, H. T heetaert', K. Hostens2,
J. Robbens1
1 Chemical M onitoring and Product Technology, Institute fo r A g ricu ltu ra l and Fisheries Research
(ILVO), B-8400 Oostende, Belgium
E-mail: qriet.vanderm eersch@ ilvo.vlaanderen.be
2 Bio-Environmental Research; Institute fo r A g ricu ltu ra l and Fisheries Research (ILVO),
B-8400 Oostende, Belgium
Marine m icroplastics can be described based on criteria such as colour, stage o f erosion, shape
(fiber, film , spherule and fragm ent) or polym er type (polyethylene, polystyrene, nylon,...). Synthetic
fibers, m ainly o rigin ated from degradation o f plastic debris such as rope and packaging m aterials,
and washing o f synthetic clothing , fo rm the m ost abundant type o f m icroplastics in the marine
environm ent.
Depending on the occurrence, bio fo u lin g and characteristics, m icro-debris could be ingested by
marine benthic species when m istaken as food. Ingestion, accum ulation and translocation o f
m icroscopic synthetic particles were dem onstrated fo r diverse marine species such as plankton
(zooplankton and phytoplankton), nem atodes (C. elegans), d ep osit feeders (blue mussel, lugw orm ,
and sea cucum bers) and crustacean (Norway lobster, am phipods, litto ra l crab and barnacles). This
suggests the potential a b ility o f m icroplastics to accum ulate in higher tro p h ic levels (fish, sea birds
and whales) by feeding on plastic-contam inated seafood or plankton.
This research presents the occurrence o f synthetic fib re s in brown shrim p (C rangon crangon) and
plastic benthic litte r (beam traw l), caught on the Belgian part o f the North Sea during spring 2013.
The extraction o f m icroplastics from the shrim p tissues was perform ed using an acid destruction
w ith a m ixture o f n itric acid and perchloric acid H N 0 3:HCI04 (4:1 v:v). For an optim al digestion o f
the tissues 500m l acid m ixture was used to digest 100g tissue. The acid digest was filte re d over a
15pm Whatman filte r and the fib re s were visualized under a stereo m icroscope. Each plastic
frag m en t was verified as plastic w ith a hot needle. Synthetic polym er types were not identified. The
results w ill be presented and discussed during the conference.
Keywords: ingestion; synthetic fibres; m icroplastics; C rangon crangon.
-118-
Stratigraphy and palaeoceanography o f a top og ra p h y-co n tro lle d
con tou rite d rift system in the Pen Duick area, Southern G ulf o f Cadiz
Vandorpe Thom as', David Van Rooij', Henk De Haas2 and Francisco Javier Hernandez-M olina3
' Renard Centre o f Marine Geology, D epartm ent o f Geology and Soil Science, Ghent University,
Krijgslaan 281 S8, B-9000 Gent, Belgium
E-mail: Thom as.vandorpe@ uqent.be
2 D epartm ent o f Marine Geology, NIOZ Royal Netherlands Institute fo r Sea Research, D epartm ent o f
Marine Geology, PO Box 59, 1790 AB Den Burg, the Netherlands
3 D epartm ent o f Earth Science, Royal Holloway U niversity London, Egham, Surrey TW20 OEX,
United Kingdom
The northern part o f the G ulf o f Cadiz has and still is receiving a lot o f atte ntio n fro m the scientific
co m m un ity due to (am ongst others) the recent IODP Expedition 339 (Novem ber 2012- January
2013). On the contrary, the southern part o f the G ulf received fa r less a tte ntio n, although mud
volcanoes, dia piric ridges and cold-w ater corals are present in th is region (Van Rensbergen et al.,
2005; W ienberg e t al., 2009). The El Arraiche mud volcano fie ld is characterized by a compressive
regime (opposed to the extensive regime in m ost o f the Gulf), creating several ridges and aiding the
m igration o f hydrocarbons tow ards the surface. This study presents seism ic and m ultibeam
evidence fo r the existence o f a co nto urite d rift at w ater depths between 550 and 650 meters along
the southw estern flanks o f the Pen Duick escarpm ent (PDE) and Gemini mud volcano (GMV), w ithin
the El Arraiche mud volcano fie ld . From the onset o f the Quaternary, when the escarpm ent started
to lift and the mud volcano originated, c o n to u ritic deposition was initiated at the fo o t o f both
topographies. Initially, fa irly low-speed b ottom currents gave rise to sheeted d rift deposits, affected
by the u p lift o f the PDE or e xtrusion o f mud fro m the GMV. From the Mid-Pleistocene onwards,
separated mounded d rift deposits form ed due to intensified b ottom currents. The m ounded nature
o f the deposits increases upward, indicating an increasing b ottom current speed. A recent AAIW
influence fo r the d rift is proposed based on CTD data and its influence during glacial periods is also
likely. However, as the northern e xten t o f glacial AAIW is not yet constrained, glacial north A tla n tic
interm ediate w ater m ig ht also play a role in the fo rm a tio n o f the d rift. The influence o f the
Mediterranean O utflow Water (MOW) is not observed at present and the changes recorded w ithin
th is contourite d rift d iffe r from the MOW-dominated contourite depositional system in the northern
G ulf o f Cadiz and the Le Danois area (Van Rooij e t al., 2010; Brackenridge e t al., 2013). D rift
deposits in the Pen Duick area o nly occur as early as the base o f the Q uaternary (compared to the
Early-Pliocene fo r the north) and m ounded d rift deposits o nly occur from the M iddle-Pleistocene
onwards (compared to the Early-Pleistocene). A ll o f these indications rule o ut a MOW-influence on
the d rift system. C old-w ater coral m ounds have been fo un d w ithin and on to p o f the sedim entary
sequence at the fo o t o f the PDE. This im plies th a t environm ental co nd itio ns in which cold-w ater
corals thrive were present in the past at the fo o t o f the PDE and not only on top.
References
Brackenridge R.E., F.J. Hernández-M olina, D.A.V. Stow and E. Llave. 2013. A Pliocene m ixed
c o n to u rite -tu rb id ity system offshore the Algarve Margin, G ulf o f Cadiz: Seismic response,
margin evolution and reservoir im plications. Marine and Petroleum Geology 46:36-50.
Van Rensbergen P., D. Depreiter, B. Pannemans, G. Moerkerke, D. Van Rooij, B. Marsset,
G. Akhm anov, V. Blinova, M. Ivanov, M. Rachidi, V. Magalhaes, L. Pinheiro, M. Cunha, J.-P.
Henriet. 2005. The El Arraiche mud volcano field at the Moroccan A tla n tic slope, G ulf o f Cadiz.
Marine Geology 21 9:1 -1 7.
Van Rooij D.,J. Iglesias, F.J. Hernández-M olina, G. Ercilla, M. Gomez-Ballesteros, D. Casas, E. Llave,
A. De Hauwere, S. Garcia-Gil, J. Acosta, J.-P. Henriet. 2010. The Le Danois C ontourite
D epositional System: Interactions between the Mediterranean O utflow W ater and the upper
Cantabrian slope (North Iberian margin). Marine Geology 274:1-20.
W ienberg C., d. Hebbeln, H.G. Fink, F. Mienis, B. Dorschel, A. Vertino, M.L. Correa and A. Freiwald.
2009. Scleractinian cold-w ater corals in the G ulf o f Cádiz— First clues about th e ir spatial and
tem poral d istrib u tio n . Deep Sea Research Part I: Oceanographic Research Papers 56:1873-1893.
-119-
Kenya-Belgium cooperation in the fra m e w o rk o f marine sciences
Vanhaecke D elphine1, Mika O dido2, Jan Mees', Tina M ertens1 and Peter Pissierssens3
1 Flanders Marine Institute, InnovOcean site
Wandelaarkaai 7, B-8400 Oostende, Belgium
E-mail: d e lo h ine.vanhaecke@ vliz.be
2 IOC Sub Com m ission fo r A frica and the Adjacent Island States, UNESCO Regional Office fo r
Eastern Africa, UN G igiri C om plex Block C, PO Box 3 0592-00100, Nairobi, Kenya
3 IOC Project Office fo r IODE, UNESCO/IOC Project Office fo r IODE
Wandelaarkaai 7 /6 1 , B-8400 Oostende, Belgium
Belgium and Kenya have a long tra d itio n o f collaboration in marine sciences. In the early eighties o f
the last century, realizing the im portance o f the w orld ocean, and the many services it provides to
society, and recognizing th a t marine sciences are an essential enterprise in the developm ent o f a
better w orld, the Belgian G overnm ent asked Professor Philip Polk to travel to Kenya and to
investigate the possibilities o f scientific collaboration. This m ission resulted in the start o f the
'Kenya-Belgium cooperation in Marine Sciences' (KBP) in 1985, which knew d iffe re n t successive
phases th a t to g e th e r ran co ntin uo usly fo r more than 1 5 years. The project was very successful w ith
a sign ifican t scientific o utp ut. It knew d iffe re n t sim ultaneous s p in -o ff projects, w ith ram ifications to
many o the r European and East-African countries.
To revitalize th is long lasting collaboration, the Kenya Marine and Fisheries Research Institute
(KMFRI) and the Flanders Marine Institute (VLIZ) recently signed a fo rm a l M em orandum o f
Understanding fo r bilateral co llaboration in the field o f marine sciences. This VLIZ-KMFRI
collaboration w ill prom ote partnership in fo llo w in g areas:
• Developm ent and execution o f collaborative research projects.
• U ndertaking jo in t field w ork, research expeditions, experim ents, m on itoring and observation
program m es.
• Exchange o f expertise and exchange o f staff, technical experts and students, including capacity
building.
• Exchange o f data and inform ation.
•
Jointly producing derived products fro m research, data and inform ation.
In May 2013 the governm ent o f Flanders donated its old research vessel Zeeleeuw to the
G overnm ent o f Kenya, which renamed it RV M tafiti, the African Swahili word fo r researcher. VLIZ
installed navigational and sam pling e quipm ent on board and provided tra in in g o f technical and
scientific staff. The arrival o f th is oceanographic research vessel w ill be a m ajor asset fo r KMFRI,
who w ill manage the ship, and fo r marine science at the East African coast in general.
The Intergovernm ental Oceanographic Com m ission o f UNESCO, in particular its program m e on
International O ceanographic Data and Inform ation Exchange (IODE), also has had long collaboration
w ith KMFRI. Building on the Marine Inform ation Exchange program m e between Kenyan and Flemish
in stitu tio n s established in the fram e w o rk o f the Kenya Belgium Project in Marine Sciences in the
198 0 ’s, IODE has developed a robust ‘Ocean Data and Inform ation N etwork fo r A frica ODINAFRICA’. W ith the support o f the Flanders - UNESCO Science T ru st fund, ODINAFRICA has
focussed on the developm ent o f capacity and infrastructure fo r the collection, processing, archival,
analysis, interpretatio n and dissem ination o f data and inform a tion products. This included the
establishm ent and equipping o f the Kenya National Oceanographic Data and Inform ation Centre
(KeNODC). Staffs o f KeNODC and the KMFRI library have been tra in in g on a wide range o f topics
related to marine data and inform a tion m anagem ent. Support was provided fo r strengthening o f the
sea level observation netw ork, preparation o f the Kenya Coastal and Marine Atlas, and developm ent
o f databases and directories crucial fo r the integrated m anagem ent o f the coastal zones (e.g.
oceanographic data, marine species, experts and in stitu tio n s, and projects). ODINAFRICA also
fa cilita te d the repatriation o f data collected in Kenyan waters fro m o the r regional and international
data centres.
References
h ttp ://w w w .v liz .b e /p ro ie c ts /k e n v a /
- 120 -
Human impacts on coastal suspended sedim ent concentrations
observed w ith Landsat 8
V anhellem ont Quinten and Kevin Ruddick
Operational Directoral Natural Environments, Royal Belgian Institute fo r Natural Sciences
G u I lede Ile 100, 1200 Brussels, Belgium
E-mail: auinten.vanhellem ont@ m um m .ac.be
We dem onstrate the capability fo r detecting suspended particulate m atter concentrations (SPM) in
coastal waters using the O perational Land Im ager (OLI) on Landsat 8 (L8) (Vanhellem ont and
Ruddick, subm itted). L8 was launched February 13, 2013 and norm al operations started on May 30,
2013. L8 has a 16-day repeat track, and offers high resolution imagery: OLI has 8 spectral bands at
30m resolution, and one panchrom atic band at 1 5m.
OLI was designed w ith a much higher signal-to-noise ratio than the instrum ents carried on previous
Landsat m issions, and has a large potential fo r marine applications. Moreover, L8/OLI data is made
freely available by USGS (e.g. h ttp ://e a rth e x p lo re r.u s q s .g o v /). A simple atm ospheric correction is
perform ed on the OLI imagery, to remove effects o f Rayleigh and aerosol scattering, based on
(Gordon and Wang, 1994) and (Ruddick e t al., 2000). Estimates o f SPM (Nechad i., 2010) are
comparable to those o f the w ell-validated MODIS-Aqua sensor.
The im pact on sea surface SPM o f various human activities is observed in OLI imagery. Increased
SPM is found in boat wakes and in the wakes o f offshore constructions, such as w ind turbines.
Dredging activities, SPM patterns w ithin harbours and around hard structures such as breakwaters
are observed. Natural processes can also be studied, such as small-scale eddies on fro n ts between
w ater masses, and high suspended sedim ents near shallow sand banks and in river plumes.
Wide-swath m edium spatial resolution (0.25 - 1km) p olar-orbitin g sensors such as MODIS-Aqua w ill
continue to be useful because o f the higher tem poral coverage: daily im agery at 50° - w ith variable
usability due to cloud cover. This makes th e ir datasets useful fo r long-term analysis and m u lti­
tem poral com posite generation (e.g. Vanhellem ont and Ruddick, 2011). However, OLI allows the
study o f small-scale processes th a t are im possible to observe at moderate resolution as its spatial
resolution (30m) is an order o f m agnitude better. The synergistic com bination o f optical sensors
providing data at d iffe re n t tim e and length scales (e.g. OLI/MODIS) may prove to be advantageous,
as already dem onstrated fo r SEVIRI/MODIS (Vanhellem ont e ta !., 2013).
References
Gordon, H.R. and M. Wang. 1994. Retrieval o f w ater-leaving radiance and aerosol optical thickness
over the oceans w ith SeaWiFS: a prelim inary a lgorithm . Appl. Opt. 3 3 :4 4 3 -4 5 2 .
Nechad B., K. Ruddick and Y. Park. 2010. C alibration and validation o f a generic m ultisensor
alg o rith m fo r m apping o f to ta l suspended m atter in tu rb id waters. Remote Sens. Environ.
1 14:854-866.
Ruddick K.G., F. Ovidi and M. Rijkeboer. 2000. A tm ospheric correction o f SeaWiFS im agery fo r
tu rb id coastal and inland waters. Appl. Opt. 39:897-91 2.
V anhellem ont Q., G. Neukermans, and K. Ruddick. 2013. Synergy between p olar-orbitin g and
geostationary sensors: Remote sensing o f the ocean at high spatial and high te m p ora l
resolution. Remote Sens. Environ.
V anhellem ont Q. and K. Ruddick (subm itted). Sedim ent plumes associated w ith offshore wind
tu rb ine s observed w ith Landsat 8. Remote Sens. Environ.
V anhellem ont Q. and K. Ruddick. 2011. Generalized satellite image processing: e ig ht years o f ocean
colour data fo r any region on earth, in: Proc. SPIE 81 75, Remote Sensing o f the Ocean, Sea lee,
Coastal Waters, and Large Water Regions 2011, 8 1 750Q (O ctober 07, 2011 ).
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Estuarine behaviour o f European silver eel (Anguilla anguilla) in the
Scheldt Estuary
Verhelst Pieterjan12, David Buysse1, Johan Coeck1, Jan Reubens2, Magda V incx2 and Ans M outon1
1 Research Institute fo r Nature and Forest (INBO), K liniekstraat 25, B-l 070 Brussels, Belgium
E-mail: pieterian ver@ hotm ail.com
2 Marine Biology Research Group, D epartm ent o f Biology, Ghent University, Krijgslaan 281 S8,
B-9000 Gent, Belgium
Estuaries are among the m ost productive ecosystems in the w orld and are characterised by high
habitat diversity. As tra n sitio n areas between inland rivers and the open sea, they fu nctio n as
tra n sp o rt zones fo r diadrom ous species like the European eel (A n g u illa anguilla), a catadrom ous
fish species th a t m igrates to the Sargasso Sea fo r spawning. Flowever, inform a tion on the m ig rato ry
behaviour o f eel in estuaries is scarce. Therefore, more insight is needed to e ffic ie n tly restore and
conserve the species. We tracked 30 eel w ith acoustic te lem etry and analysed th e ir behaviour in the
estuary o f the Scheldt River between July 2012 and September 2013. Eels m igrated during late
sum m er and early autum n and used specific m igration routes in the estuary to reach the North Sea.
The relation between eel behaviour and environm ental co nd itio ns like tid a l currents, flow , w ater
tem perature or lig h t inten sity was analysed. No retention period was observed, which could indicate
th a t silver eel do not feed while m igrating and o nly use the estuary as a m igration path. The Scheldt
Estuary has a lot o f anthropogenic activities, including dredging to ensure navigation depth o f
certain channels. Therefore, our results allow to set up a m anagem ent plan to optim ise
anthropogenic activities and guarantee conservation o f the eel population.
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Deep phylogeny o f the am phipod super-fam ily Eusiroidea
Verheye M. and C. d ’Udekem d ’Acoz
D epartm ent o f Recent Invertebrates, Royal Belgian Institute o f Natural Sciences,
B-1000 Brussels, Belgium
E-mail: mverheve@ naturalsciences.be
The super-fam ily Eusiroidea is tra d itio n a lly divided into 4 fam ilies, nam ely C alliopiidae, Eusiridae,
Gammarellidae and Pontogeneiidae (De Broyer e t al., 2007), but recent phylogenetic data suggests
th a t the eusiroid clade form s a much broader assemblage (Englisch, 2001). Representatives are
found in all oceans, inh ab iting every tro p h ic niches and a wide bathym etric range. With 216
described species in the Southern Ocean (i.e. a bo ut 24% o f its known am phipod fauna), eusiroids
constitute a sign ifican t fraction o f the A n ta rctic and sub-Antarctic bio dive rsity (De Broyer e t al.,
2007).
The eusirid concept is very inadequately defined m orphologically. The super-fam ily fo rm s a diverse
assemblage o f taxa o f gam m aroid fo rm , g lo ba lly characterized by the loss or reduction o f the
accessory fla ge llu m (Bousfield & Hendrycks 1995). The fa m ily assignm ent o f genera is often
challenging, since there is no consistent set o f diagnostic characters defin in g m ost o f them . The 6
fam ilies fo rm e rly com prised in the non-validated taxon Iphim edioidea (Lowry & Myers 2000), as well
as the Astyridae and Stilipedidae were recently considered as eusiroids. Moreover, previous 18S
phylogenetic reconstructions revealed th a t the Astyridae, Iphim ediidae, Epimeriidae and Pleustidae
are nested w ith in the eusiroid clade (Englisch 2001).
With the aim o f clarifying those m ajor nom enclatural uncertainties and discussing the phylogenetic
relationships, a deep phylogeny o f the super-fam ily Eusiroidea, including representatives o f all the
aforem entioned fam ilies, was reconstructed using tw o d iffe re n t gene fragm ents (28S rRNA and 1 8S
rRNA). The analysis was perform ed at a global scale, m ostly w ith A n ta rctic taxa, but also European
and A rctic species.
The study confirm s th a t the Eusiroidea fo rm s a m ust broader
clade than
claimed inclassical
literature. It revealed th a t m ost o f the tra d itio n a lly d elim ited fam ilies are not m onophyletic and that
a few taxa previously considered as eusiroids {Gam m arellus, Cleippides) are in fa ct very d ista n tly
related, and therefore should be excluded fro m them . Eusiroids com prise several independent
arm oured and spiny lineages nested am ongst taxa w ith plesiom orphic m orphologies, suggesting
convergent evolutions and rapid m orphological specializations under intensive selection pressures.
The lim its o f the super-fam ily and its com posing clades have to be com pletely re-established in the
lig h t o f th is new genetic dataset. This study enables a clearer understanding o f the ta xon om y o f
one o f the m ajor am phipod assemblage in the Southern Ocean and gives us insights into the
patterns o f its phenotypic evolution. It proposes a solid fram e fo r fu rth e r analysis o f the systematics
o f various A n ta rctic eusiroid lineages, especially the epim eriid and iphim ediid clades, which w ill be
studied in more depth.
References
Bousfield E.L. and E.A. Hendrycks. 1995. The am phipod superfam ily Eusiroidea in the North
Am erican Pacific region. I. Family Eusiridae: system atic and d is trib u tio n a l ecology.
A m phipacifica l(4 ):3 -5 9 .
De Broyer C., J.K. Lowry, K. Jazdzewski and H. Robert. 2007. Volum e 1: Part 1. Catalogue o f the
Gammaridean and C orophiidean A m phipoda (Crustacea) o f the Southern Ocean w ith
d istrib u tio n and ecological data. Bulletin de I’In stitu t Royal des Sciences Naturelles de Belgique
77(1): 47-64.
Englisch U. 2001. Analyse der Phylogenie der A m phipoda (Crustacea, Malacostraca) m it Hilfe von
Sequenzen des Gens der RNA der kleinen ribosom alen Untereinheit. Phd thesis. RuhrUniversität Bochum, Germany.
LowryJ.K. and A.A. Myers. 2000. A fa m ily level phylogeny o f iphim edioid am phipods (Crustacea,
Am phipoda). [Abstract] Xth International C olloquium on A m phipoda, H eraklion, 16-21 A p ril
2000: 30.
- 123 -
Post-trawling damage and m o rta lity am ongst brown shrim p (Crangon
crangon L.) in the Flemish shrim p fishery
Vermeersch Xavier and Geertrui Vlaem ynck
In stitu u t vo or Landbouw en Visserij Onderzoek (ILVO), Brusselsesteenweg 370, B-9090 Melle, België
E-mail: Xavier.Vermeersch@ ilvo.vlaanderen.be
The Flemish brown shrim p fisheries wish to d ive rsify th e ir o ffe r by adding live brown shrim p
(Crangon crangon) to th e ir current product gamma. Until recently brown shrim p fro m Belgian
fish in g vessels have o nly been available as a cooked product th a t is being processed and boiled at
sea. The shrim p is caught at n ig h t in a tra d itio n a l m anner using tw in beam traw ls w ith tow ing tim es
th a t are typ ically one to tw o hours. The fresh ly caught live shrim p is m echanically sieved
im m ediately after em ptying the nets in ord er to separate it from unwanted by-catch. It is then
cooked in seawater and stored on ice. This action is repeated after each to w till the break o f dawn.
The vessels then land th e ir catch in the fo rm o f a pre-cooked shrim p in one o f the Belgian fishing
harbors after roughly twelve hours at sea.
In order to land live shrim p, sieved shrim p from the last to w are stored in shallow crates under
atm ospheric conditions. Brown shrim p can survive o ut o f the w ater fo r many hours when kept under
optim al conditions. However, research has revealed th a t the rotary sieves th a t are w idely used to
sort the catch can in flic t a sign ifican t am ount o f damage to the shrim p, th erefore reducing th e ir
a b ility to remain alive.
The s h rim p ’s survival is com prom ised by both internal injuries and external w ounds such as
damage to the exoskeleton. In o rd e r to evaluate the survival rate am ongst brown shrim p during and
a fte r handling on board recovery experim ents were conducted where the shrim p were placed in
tanks w ith natural seawater after landing.
The m o rta lity am ongst sieved shrim p may be as high as 90% when no care is taken to m anipulate
them accordingly, w hile a m o rta lity as low as 20% is seen when great care is taken and the
mechanical sieving step is replaced by manual sieving. In o rd e r to fu rth e r develop the live brown
shrim p as a new product in the Flemish fishery, every step during the early handling and sieving
process m ust be executed fo llo w in g good handling practices to prevent damage and fo r live shrim p
to be stored on board under optim al conditions.
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Performance com parison o f local and non-local genotypes of
A m m o p h ila a re n a ria in the Flemish coast and evaluation o f the
effects on a specialist herbivore
Verm ote ELine, C harlotte Van M oorleghem and Eduardo de la Peña
T errestrial Ecology Unit, D epartm ent o f Biology, Ghent University, K.L. Ledeganckstraat 35,
B-9000 Gent
E-mail: eline.verm ote@ uqent.be
A m m ophila a re n a ria , marram grass, is a sand-fixing plant species o f coastal dunes th a t occurs
naturally in M editerranean and A tla n tic Europe. For th is reason, it is co m m only used fo r the
sta bilizatio n and restoration o f coastal dunes (in Europe and elsewhere). C urrent and tra d itio n a l
dune managem ent practices often rely on the in tro d u ctio n o f a llo pa tric marram stands fo r sand
fixa tio n . Flowever, the in tro d u ctio n o f such exogenous plant m aterial can have im p o rta n t effects at
local level. To o ptim ize the current managem ent and conservation strategies o f these natural
systems it is necessary: (I) to assess w hat type o f plant m aterial is o ptim al (in term s o f grow th and
survival) fo r re-vegetation purposes and (II) w hat are the effects on the associated com m unity. With
th is in mind, we conducted tw o d iffe re n t experim ents; by means o f a ‘com m on garden e x p e rim e n t’
in three Flemish nature reserves, we com pared the grow th and survival o f d iffe re n t genotypes o f
A m m ophila a re n a ria (com ing from d iffe re n t areas o f the North Sea and A tla n tic Europe); in a
second (laboratory) experim ent, we evaluated the effect o f these marram populations on the
m ultip lica tio n o f Schizaphis ru fu la , a specialist aphid inhabiting coastal dunes. The results o f the
com m on garden expe rim en t show th a t geographic distance to the location o f intro du ction is an
im p o rta n t fa cto r in the survival and perform ance o f marram grass populations. Similarly, the
geographic origin o f the plant populations was crucial in aphid perform ance.
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M odelling - alternative resource fo r oil risk assessment?
Viaene Karel
Lisette de Hoop2, Jan H endriks2, Frederik De Laender3 and Colin R. Janssen1
1 GhEnToxLab, Ghent University, J. Plateaustraat 22, B-9000 Ghent, Belgium
E-mail: karel.viaene@ uqent.be
2 Institute fo r Water and W etland Research, D epartm ent o f Environm ental Science, Radboud
University Nijm egen, PO Box 9010, NL-6500 GL, Nijm egen, the Netherlands
3 Nam ur University, Research Unit in Environm ental and Evolutionary Ecology, Belgium
Crude oil can be introduced into the marine environm ent via natural seeps a n d /o r human activities.
Events like the Deepwater H orizon oil spill show the need to assess the effects o f crude oil on
marine biota. Q uantitative inform a tion on the effects o f oil on ecologically relevant endpoints such
as survival and reproduction is im p o rta n t fo r risk assessment. However, few e xperim ental studies
have assessed the im pact o f oil co nstitu en ts on these endpoints. Models may be helpful to assess
effects o f oil on the survival and reproduction o f aquatic organism s th a t have remained untested.
Yet, u ntil now, a generic m odel qua ntifyin g accum ulation and effects o f oil co nstituents is lacking.
The goal o f the cu rren t study was therefore to develop a m odel, applicable to a wide range o f
species, to q u a n tify the bioaccum ulation o f oil co nstituents in aquatic organism s and to estimate
the corresponding effects on th e ir survival.
We predicted the bioaccum ulation based on o rg an ism ’s properties such as wet w eight, lipid content
and rate constants o f the chemical. The octanol-w ater p a rtitio n co efficie nt (K ) o f the chemical was
another key m odel parameter. Predicted body burdens were used in concentration-response
fu nctio ns to calculate m o rta lity rates. To assess th e ir accuracy, we applied the models to published
data fo r d iffe re n t species and oil constituents, and com pared our m odel predictions w ith observed
values.
As an exam ple, we estim ated the survival o f the am phipod H yalella azteca exposed to five
fluoranthene concentrations. The m o rta lity rate predicted by the m odel was used to sim ulate the
surviving fra ctio n o f a H. azteca population. M o rta lity due to fluoranthene is accurately predicted
fo r the highest concentration (2 5 0 p g /l) but is underestim ated (up to 20% deviation) fo r the
6 2 .5 p g /L and 1 2 5 p g /L treatm ents. However, considering th a t the OMEGA bioaccum ulation model
requires lim ited data in p u t and th a t general oil to x ic ity values were used to predict the effects o f
pyrene, it can be concluded th a t th is approach shows potential fo r the data sparse risk assessment
o f oil.
- 126 -
Com parison o f density estim ators in coastal populations using a
m odelling approach
V oigt Maria123, Hichem G herraz', Uwe G riiters4, Nico Koedam2 and Farid Dahdouh-Guebas12
1 Laboratory o f Systems Ecology and Resource Management, Université Libre de Bruxelles - ULB,
Av. F.D. Roosevelt 50, CPI 2 6 4 /1 ,1 0 5 0 Brussels, Belgium
E-mail: mvoiqt@ vub.ac.be
2 Laboratory o f Plant Biology and Nature Management, Vrije U niversiteit Brussel - VUB, Pleinlaan 2,
1050 Brussels, Belgium
3 Ecology Center, Kiel University, Olshausenstraße 75, House I, D -2 4 1 1 8 Kiel, Germany
4 Institute o f Forest Biometrics and System Analysis, Technical U niversity o f Dresden - TUD, Pienner
Straße 8, D -01737 Tharandt, Germany
The earth is facing a b io dive rsity crisis and coastal ecosystems like mangroves, coral reefs and
seagrass beds are severely declining in spatial e xte n t and com position (Duke et al., 2007; Stone,
2007; Cressey, 2009). In th is light, the assessment o f these com m unities and th e ir bio dive rsity
becomes increasingly im p orta nt. Reliable estim ates o f population density and related parameters
fo rm an integral part o f such studies, because th ey allow the detection o f changes in species
com position and consequently the conservation o f endangered ecosystems.
D ifferent m ethods have been used to obtain population density estim ates o f non-m otile organism s.
They are based e ither on counting the individuals in an area (plot-based) or on determ ining the
distance between them (plot-less) (Krebs, 1999). While plot-based m ethods are robust and provide
good estim ates when applied to populations w ith d iffe re n t patterns, th e y are labour intensive. Plot­
less estim ators, on the o the r hand, are less tim e consum ing, but often heavily biased (Magnussen et
a i, 2012). Many researchers continue to use plot-less m ethods, even th ough very high errors have
been reported (Hijbeek e t a i, 2013). It is thus tim e ly to device to ols to help in the decision about
the o ptim al density estim ation m ethods fo r d iffe re n t study systems.
A m odel was w ritte n in the individual-based m odelling language NetLogo (Khan M.N.I., Gherraz H.,
G riiters U., Dahdouh-Guebas F., unpublished results). It allows the user to create a virtua l
population w ith d iffe re n t co nfig uratio n possibilities fo r p o in t patterns, diam eter d is trib u tio n ,
species com position and zonation. It includes a set o f estim ation m ethods, and the option to
choose between sam pling designs and sizes. The m odel calculates the true density, area and
frequency and a d d itio n a lly provides th e ir estim ation as obtained by the d iffe re n t m ethods. It was
designed considering especially coastal ecosystems w ith th e ir d is tin c t zonation, co m p le x ity and
d iffic u lty o f access. A fte r a p ilo t study in the fie ld , the user can rebuild the ecosystem in the model
and use it to fin d the best estim ation m ethod in term s o f accuracy, precision and efficiency fo r the
respective study area.
In the on-going project, we w ill fu rth e r develop the m odel (1) to include an option to e ither calculate
the sample size based on a least accepted e rro r or calculate the e rro r based on a predefined sample
size, and (2) to calculate the efficiency o f each m ethod. The sam pling e ffo rt, which is usually
assessed based o nly on com m on sense, w ill be estim ated as a fu n ctio n o f the num ber o f individual
m easurem ents executed and the distance covered between them . The upgraded m odel w ill be
rig oro usly tested fo r a num ber o f scenarios com prising d iffe re n t co nfig uratio ns o f the input
parameters. The outcom e o f th is study w ill be a catalogue o f indications fo r density estim ation
m ethods in populations w ith d iffe re n t patterns, considering especially the p articularities o f coastal
ecosystems.
References
Cressey D. 2009. Vital marine habitat under threat. Nature.
Duke N.C., J.-O. Meynecke, S. D ittm ann, A.M. Ellison, K. Anger, U. Berger, S. Cannicci, K. Diele, K.C.
Ewel, C.D. Field, N. Koedam, S.Y. Lee, C. Marchand, I. Nordhaus and F. Dahdouh-Guebas.
2007. A w orld w ith o u t mangroves? Science 317:41 -42.
Hijbeek R., N. Koedam, M .N.I. Khan, J.G. Kairo, J. Schoukens and F. Dahdouh-Guebas. 201 3. An
evaluation o f plotless sam pling using vegetation sim ulations and field data fro m a
mangrove forest. PLoS ONE 8, e 6 7 2 0 1 .
Krebs C.J. 1999. Ecological m ethodology, B enjam in/C um m ings Menlo Park, C alifornia.
Magnussen S., L. Fehrman and W.J. Platt. 201 2. An adaptive com posite density estim a tor fo r k-tree
sam pling. European Journal o f Forest Research 131:307-320.
Stone R. 2007. A w orld w ith o u t corals? Science 316:678-681.
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Towards a com p ilation o f biological tra it data fo r European
macroalgae
Vranken Sofie1 2, Stefanie Dekeyzer2, Leen Vandepitte2, Simon Claus2, O livier De C lerck1
1 Phycology Research Group, Ghent University, Krijgslaan 2 8 1 -S8, 9000 Ghent, Belgium
2 Flanders Marine Institute (VLIZ), InnovOcean site, Wandelaarkaai 7. B-8400 Oostende
E-mail: sofiev@ vliz.be
Elucidating the mechanisms th a t shape large-scale patterns o f d ive rsity requires not o nly a good
estim ate o f the ta xon om ic d ive rsity and param eters describing the physical environm ent, but also
o f biological data. The interactions o f organism s w ith th e ir e nvironm ent and w ith o th e r organism s
are determ ined by biological tra its rather than ta xon om ic nom enclature (Tyler e t al., 2012). The
trait-based approach in co m m un ity and m acro-ecology has gained a lot o f interest recently.
However, even th ough many o f these ecological im p o rta n t tra its have been docum ented in the past,
these are neither available in p ublically accessible databases nor linked to ta xon om ic and
biogeographic databases. C ollecting tra it data therefore tends to be very tim e consum ing. Here we
aim to com pile a m atrix o f tra its relevant to m acro-ecology and large-scale co m m un ity ecology fo r
the marine macroalgae in Europe. T raits include life history and reproductive characteristics, grow th
form , ecology, d is trib u tio n and habitat. Because o f uncertainty on species level d ive rsity fo r m ost
seaweeds, tra its are docum ented on a genus level. The project is issued in the fram ew ork o f the
EMODnet Biology project to com plete the biological tra it inform a tion in the W orld Register o f Marine
species (WoRMS; Appeltans et al., 2012) developed by the Flanders Marine Institute (VLIZ).
References
Appeltans W. et al. 2012. The m agnitude o f global marine species diversity. C urrent Biology
23:2189-2202
Tyler E.H.M., P.J. Som erfield, E. Vanden Berghe, J. Bremner, E. Jackson, O. Langmead, M.L.D.
Palomares and T.J. Webb. 201 2. Extensive gaps and biases in our knowledge o f a well-known
fauna: Im plications fo r integrating biological tra its into macroecology. Global Ecology and
Biogeography 2 1 :922-934
WoRMS Editorial Board. 2014. W orld Register o f Marine Species. Available from
h ttp ://w w w .m a rin esp e cie s.o rg at VLIZ. Accessed 2014-01-06
- 128 -
Demo o f the LifeWatch web services: online data processing tools fo r
biod ive rsity research
Waumans Filip, Robin H outhoofdt, Bart Vanhoorne, Stefanie Dekeyzer, A ina Trias Verbeeck,
Leen Vandepitte, Klaas D eneudtand Francisco Hernandez
Flanders Marine Institute (VLIZ), InnovOcean site, Wandelaarkaai 7, B-8400 Oostende, Belgium
E-mail: filip.w aum ans@ vliz.be
To su pp ort and encourage scientific research on bio dive rsity and ecosystem fu n ctio n in g , Europe
launched LifeWatch w ith in the European Strategy Forum on Research Infrastructures (ESFRI).
LifeWatch fu nctio ns as a central virtua l laboratory, integrating observatories, databases, web
services and m odelling to ols d istrib u te d th ro u g h o u t Europe.
As part o f the Flemish co n trib u tio n s to LifeWatch, the Flanders Marine Institute (VLIZ) set up an
online data portal where scientists can use several web services to process b io dive rsity data
(h ttp ://life w a tch .b e /d a ta -se rvice s ). These web services assist in data standardization, q u a lity
control, visualization, analysis and retrieval o f additional data.
Users o f the data portal can choose to use a demo file or can upload th e ir own data files. For the
latter a log-in and password are required and can be requested by anyone. Both marine and
te rre stria l data can be uploaded. An extensive manual is available describing which inp ut is required
fo r each web service. The web services can also be used in a concatenated way as is dem onstrated
in several use cases.
The resulting data file contains e xtra colum ns in addition to the data in the origin al file. The original
data file, the resulting data file and a sum m ary report are stored on the server and linked to the
user’s account. This allows the user to retrieve the files later, at a n y tim e .
The num ber o f available services w ill increase in the next years. Services c u rre n tly available are:
• Data validation and Q uality C ontrol (QC) services: The LifeWatch portal uses a specific data form at,
based on the OBIS scheme and the Darwin Core. Part o f th is application w ill check if the data file
uploaded by the user matches th is LifeWatch data form at. This application can also check if the
uploaded data file matches the OBIS scheme. And th ird ly th is application can p lo t the coordinates
in the uploaded data file on a map to check if the observation points are marine or te rre stria l.
• M arineregions gazetteer services: Based on the latitude and longitude values and place names in
the data file uploaded by the user, th is application w ill return additional inform a tion derived from
M arineregions (MRGID, preferred gazetteer name, etc.).
• Taxonom ical services: Based on the scientific names in the data file uploaded by the user, this
application w ill check if these names already exist in ta xon om ic databases or nom enclatures such
as the World Register o f Marine Species (WoRMS), Catalogue o f Life (CoL), the Integrated
Taxonom ic Inform ation System (ITIS), the Pan-European Species d irectories Infrastructure database
(PESI), the Global Names Index (GNI), the International Plant Names Index (IPNI), Index Fungorum
(IF) and the Paleobiology Database (PaleoDB). It is possible to match your data file w ith each
ta xon om ic database separately or in a com bined way.
• Tidal services: Based on the latitude, longitude and tim e values in the data file uploaded by the
user, th is application w ill calculate the w ater level based on tid a l data fo r observations in the
Belgian part o f the North Sea.
• Geographical services: Based on the latitude and longitude values in the data file uploaded by the
user, th is application w ill retrieve inform a tion about adm inistrative boundaries, bathym etry,
biogeographical classification, features, protected areas, to ta l biological valuation, etc.
A t the VLIZ Young Marine Scientists Day the use o f the LifeWatch web services w ill be dem onstrated
in an anim ated way.
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Epibenthic com m u nities in the coastal waters o f Suriname
W illems T o m a s '2, Annelies De Backer', Kris Hostens' and Magda V incx2
' Institute fo r A g ricu ltu ra l and Fisheries Research (ILVO), Biological Environm ental Research
A nkerstraat 1, 8400 Oostende, Belgium
Email: tom as.w illem s@ ilvo.vlaanderen.be
2 Marine Biology Section, D epartm ent o f Biology, Ghent University, Krijgslaan 281 S8, 9000 Gent,
Belgium
The continental shelf o f Suriname stretches some 200km offshore South-Am erica’s North coast,
sloping g en tly before plunging into the depths o f the Western A tla ntic. The area is heavily
influenced by sedim ent-laden freshw ater discharge from both the Am azon basin and dom estic
rivers, creating m ajor environm ental shifts. It is cu rren tly underinvestigated how b ottom -living
organism s respond to th is variable environm ent, as biological data from the area are scarce and
outdated. The current study th e re fo r aims to characterize the e pibenthic com m unities on the
coastal shelf o f Suriname, and to assess th e ir spatio-tem poral variability.
During 10 survey cruises, five locations o f increasing depth, starting at 5m near estuaries and going
offshore to 35m, were sampled in each o f three transects located from east to west. On these 15
locations, epibenthos was sampled w ith an o tte rtra w l on a (bi)m o nth ly basis in 2012-2013.
Sim ultaneously, the environm ental param eters tu rb id ity , chlorophyll, w ater tem perature, salinity
and sedim ent com position were measured.
A to ta l o f 92 e pibenthic species were encountered, living in spatially d is tin c t com m unities. Beneath
a depth o f 25m, a coastal co m m un ity was discerned, dom inated by a single species, the A tla n tic
seabob shrim p Xiphopenaeus k ro y e ri (Crustacea: Penaeoidea), which is present in densities o f up to
1300 individuals 1 0 0 0 m 2. Near the 30m isobaths, the epibenthos co m m un ity a b ru p tly shifted to a
more diverse offshore species assemblage w ith o u t X. kroyeri. As such, the main fa c to r structuring
the epibenthos was a gradient in depth, corresponding to a tra n sitio n in sedim ent com position from
mud and sandy mud inshore, to sand w ith shell fragm ents offshore. In the offshore com m unity, a
second pattern was apparent. Brittlestars dom inated the epibenthos in the west, w ith densities o f
Ophioderm a brevispina and Ophiolepis elegans reaching 370 individuals 1 0 0 0 m 2. They were
absent, however, on the same depths in the eastern part, were the soft coral Renilla m u e lle ri and
the herm ite crab D ardanus focusus were num erically dom inant. This east to west g radient is
probably caused by the Am azon o u tflo w because the influence o f the Am azon plume on coastal
waters and sedim ents decreases when going westwards.
The environm ental v a ria b ility on the coastal shelf o f Suriname is clearly reflected in the epibenthos.
Understanding these patterns is im p o rta n t considering the artisanal and sem i-industrial e xp lo ita tio n
o f the seabob shrim p X. kroyeri. As such, th is study can co ntribu te to an ecosystem approach in the
m anagem ent o f these shrim p fisheries in Suriname.
- 130 -
Wave m o n ito rin g Broersbank: measurem ent campaign and m odelling
Yam am oto Hana O rtega1, Stephanie Van de Vreken2, Homayoon K o m ijani1 and Jaak M onbaliu1
1 Hydraulics Laboratory, D epartm ent o f Civil Engineering, KU Leuven, Kasteelpark Arenberg 40, PO
Box 2448, 3001 Heverlee, Belgium
E-mail: iaak.m onbaliu@ bw k.kuleuven.be
2 Agentschap vo or M aritiem e D ienstverlening en Kust, A fde lin g Kust, Vrijhavenstraat 3,
8400 Oostende, Belgium
Along the Belgian coast, wave energy is dissipated by a num ber o f shallow banks. To better
understand and characterize and consequently m odel wave propagation and dissipation tow ards the
coast an intensive wave m easurem ent campaign has been designed. Five w averider buoys (2
directional and 3 non-directional) have been deployed between W esthinder and the Broersbank by
the Coastal Division o f MDK.
The buoys have been operational since the end o f November 2013 and have been able to record
some firs t storm s. Note th a t being situated in the Western part o f the Belgian C ontinental Shelf, the
new buoys provide very com plim entary wave inform a tion to th a t com ing fro m the ‘ Meetnet Vlaamse
Banken’ o f the Coastal Division o f MDK.
By analysing the measurem ents and com paring them w ith high resolution spectral m odelling, the
ta rg et is to achieve in the firs t place a better knowledge about the dissipation rates o f waves
passing over shallow banks. Good knowledge o f wave energy dissipation capacity o f shallow
sandbanks has im p o rta n t applications including assessing th e ir potential as coastal protection. It is
also an im p o rta n t step in characterizing the wave energy th a t still w ill need to be dissipated on the
beach itself. KU Leuven w ill study the results o f the measurements.
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Direct and indirect effects o f macrofaunal fun ction al diversity and
bacterial and archaeal c o m m u n ity characteristics determ ine benthic
nitrogen cycling in coastal marine sediments
Yazdani M aryam 12, Ulrike Braeckman', Sofie Derycke', Melanie Sapp3, Anne W illem s4, Magda V in cx1
and Jan Vanaverbeke1
1 Marine Biology Research Group, Biology D epartm ent, Ghent University, Krijgslaan 281/S8,
B-9000 Ghent, Belgium
E-mail: M arvam.YazdaniFoshtomi@ Uqent.be
2 Iranian National Institute fo r Oceanography, D epartm ent o f Biology, PO Box 141 55-4781,
Tehran, Iran
3 Low estoft Laboratory, Centre fo r Environm ent, Fisheries and Aquaculture Science (CEFAS), Suffolk,
UK; and Oceanlab, U niversity o f Aberdeen, Aberdeenshire, United Kingdom
4 Laboratory o f M icrobiology, D epartm ent o f Biochem istry and M icrobiology, Ghent University,
K.L. Ledeganckstraat 35, B-9000 Ghent, Belgium
Nitrogen (N) is m ost often im plicated as the n u trie n t lim itin g prim ary production in the coastal
ocean. Sediments are im p o rta n t sites fo r N cycling in coastal ecosystems.
Nearly half o f the produced prim ary production is eventually deposited o nto the shallow continental
shelf seafloor, where benthic activities (bioturba tion , b io -irrig a tio n ) play a fundam ental role in the
recycling o f nutrients needed by prim ary producers back into the w ater colum n.
However, it is w ell-known th a t the n utrien t cycle is resulting fro m the activity o f m icroorganism s
(bacteria and archaea). Hence, the a ctivity o f m acrofauna has an indirect effect on benthic n utrien t
cycling th ro ug h its d irect effect on m icrobial com m unities.
Recent studies have shown th a t m acrofaunal fu nctio na l d ive rsity indeed affects the structure and
a ctivity o f benthic m icrobial com m unities in e xperim ental settings. However, fie ld studies, linking
m acrofaunal fu n ctio n a l diversity, m icrobial d ive rsity and n u trie n t cycling have not been conducted
so far. Here, we report on such an a tte m p t from shallow North Sea sediments.
We sampled fo r macrofauna, bacteria and archaea in general, and am m onia o xid isin g bacteria (AOB)
and archaea (AOA) in detail, in 7 sam pling stations covering various sedim ent types (muddy, fine
sandy and permeable) during the peak spring bloom (April), sh ortly a fte r mass sedim entation (J u n e )
and during the period o f highest benthic m ineralisation rates (September).
Measured n itrifica tio n rates were highest in September, where th ey coincide w ith high benthic
b io tu rb atio n a ctivity especially in fine sedim ents and the highest OTU richness o f bacterial and
archaeal n itrifyin g com m unities (AOB and AOA).
Macrofauna effects were indeed affecting the d ive rsity o f n itrify in g organism s (AOB and AOA), and
the general bacterial com m unity.
Furtherm ore, to g e th e r w ith some sedim entary a biotic variables, biotic variables, including spatial
and seasonal changes in the Bioturbational Potential o f m acrofaunal C om m unities (BPc) and
richness or d ive rsity o f bacteria sig n ifica n tly affected d e n itrific a tio n rates and the overall sedim ent
N -m ineralization.
Our results thus reveal th a t the presence and fu nctio na l d ive rsity o f m acrofaunal com m unities
indeed affects benthic m ineralisation processes in field situations by affecting the biogeochem ical
properties o f the sedim ent and hence the d ive rsity o f the m icrobial com m unities active in these
processes.
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Diversification o f Mediterranean Cystoseira (Fucales, Phaeophyceae)
using a RAD-Seq approach
Zervas D im itrios, Kyung Min Lee, Sofie D’Hondt and O livier de Clerck
Phycology Research Group, Ghent University, Krijgslaan 2 81 -S8, 9000 Ghent, Belgium
E-mail: dim itriszer@ vahoo.qr
The brown algal genus Cystoseira represents a very im p o rta n t com ponent o f shallow w ater coastal
environm ents in the Mediterranean Sea. The plants typ ically fo rm dense vegetations, creating a
habitat fo r a m ultitu de o f vertebrate and invertebrate species. A b o u t 29 d iffe re n t taxa (species and
intraspecific taxa) have been recognized. Resolving th e ir e volutionary relationship however proves
very d iffic u lt, due to the recency o f th e ir origin and m ost probably ongoing hybridisation between
closely related taxa. In th is study we aim to investigate the e volutionary h istory o f the Cystoseira
(clade-5 sensu Draimsa et al. 2010) and disentangle the roles o f geography versus and ecology in
the d iversification process. Seven species have been selected: C. am entacea var. stricta,
C. brachycarpa, C. c rin ita , C. funki, C. m editerranea, C. ta m a ris c ifo lia and C. zostertoides. Most o f
the individuals sampled were located across the M editerranean Sea, w ith few o f them collected from
the A tla n tic coasts o f Spain and France.
Restriction site Associated DNA (RAD) tags, were used, as a cost-effective polym orphism
ide ntifica tion m ethod, to be up to par w ith the evolving Next Generation Sequencing Techniques
(Davey e t al., 2011). RAD tags are genome wide, short DNA sequences, associated w ith a specific
restriction enzyme. We used S b f\to generate thousands o f markers fro m which gene and species
w ill be constructed under a m ultispecies coalescent fram ew ork.
Our study presents the firs t RAD-Seq approach fo r algal species. Results are expected to provide
new insights on C ystoseira’s phylogeny and d iversification in the M editteranean basin fo llo w in g the
end o f the Messinian salinity crisis (5 mya).
References
Davey J.W., P.A. Hohenlohe, P.D. Etter, J.Q. B ooneJ.M . Catchen and M.L. Blaxter. 2011 Genome-wide
genetic m arker discovery and genotyping using next-generation sequencing. Nature Reviews
Genetics 12:499-510.
Draisma S.G.A., e. Ballesteros, F. Rousseau and T. T hibaut. 2010. DNA sequence data dem onstrate
the polyphyly o f the genus cystoseira and o the r Sargassaceae genera (Phaeophyceae). Journal
o f Phycology 46:1329-1345.
- 133 -
APPLICANTS
VLIZ THESIS AWARDS MARINE
SCIENCES 2013
Bioaccumulatie van organische polluenten in haaien en roggen van
de oo stkust van de VS
Briels Nathalie
O nderzoeksgroep SPHERE (Systemic Physiological & Ecotoxicological Research, Biologie
(A fstudeerrichting Evolutie en Gedrag), U niversiteit Antw erpen
E-mail: nathalie briels@ hotm ail.com
Door hun rol ais toppredatoren en hun lange levensduur kunnen kraakbeenvissen hoge
concentraties van persistente organische polluenten (POP’s) accum uleren. Vele haaien en roggen
leven bovendien in kustgebieden en estuaria om er te reproduceren en hun jo n g e n g ro o t te
brengen. Net deze gebieden zijn uiterst vatbaar voor vervuiling, aangezien onder meer industriële
en agriculturele ru n -o ff en onbehandeld rioolw ater er via de rivieren te re chtkom t. In deze studie
werden kapham erhaaien (Sphyrna tiburo), citroenhaaien (N egaprion b revirostris), stierhaaien
(C archarhinus leucas), zw artpunthaaien (C archarhinus lim batus) en Atlantische pijlstaartroggen
(D asyatis sabina) u it de kustwateren van Florida o nderzocht op aanwezigheid van POP’s. Er werd
meer bepaald o nd erzoch t hoe die POP’s werden overgedragen via trofische en reproductieve
transfer. Uit de resultaten bleek dat stierhaaien de hoogste POP concentraties accum uleerden door
hun hoge trofische positie. A tlantische pijlstaartroggen accum uleerden de laagste concentraties.
Kaphamerhaaien hadden hogere PCB concentraties dan citroenhaaien, hoo gstw a arschijn lijk door
hun aanwezigheid nabij een met A ro clo r 1268 gecontam ineerde site, maar alle andere POP’s
accum uleerden meer in citroenhaaien. Bovendien werden er ook POP’s doorgegeven via het
reproductieve systeem van de moeder. PCB concentraties waren zelfs hoger in de levers van
e m b ryo ’s dan in de lever van hun moeders. Voor de andere polluenten was er geen duidelijke
voorkeur vo or accum ulatie in een bepaald weefsel, hoewel er in de ova en ovaria ook aanzienlijke
POP concentraties werden gedetecteerd. Aangezien er aanzienlijke concentraties werden
teruggevonden in alle onderzochte soorten en aangezien de mens ook haaien eet, werd de
consum ptie van haaienvinnensoep ook onderzocht. Tijdens het bereiden van de soep worden de
vinnen meermaals g eko okt en w o rd t het kookw ater telkens verw ijderd. Ondanks deze kook-stappen
werden de meest persistente en vetoplosbare polluenten nog steeds teruggevonden in de
uiteindelijke soep, hetzij niet in schadelijke concentraties.
- 136 -
M orphological changes in the Zwin and Westerschelde estuaries: an
analysis o f historical maps
De Nui P ieterjan
Ecosystem Research Management Group, U niversiteit Antwerpen
E-mail: pieteriandenul@ m e.com
In tro d u ctie
Definities
Tijslag is het volum e w ater (in m 3) dat bij hoog tij het estuarium instro om t. Oppervlaktedoorsnede is de dwarsdoorsnede (in m2) van een getijdengeul bij gem iddeld tij.
Dit onderzoek fo cust op de getijdengeul van zowel het Zwin ais het Westerschelde estuarium .
Uit de lite ra tu u r (Meyvis e t a i, 2003; Coen, 2008) is bekend dat zowel in het Zwin ais het
Westerschelde estuarium een g ro o t oppervlak aan slikken en schorren zijn ingepolderd gedurende
de geschiedenis. Doei van d it onderzoek is om te onderzoeken wat de invloed was van die
inpolderingen op de dim ensies van de getijdengeul gedurende de geschiedenis.
Uit de lite ra tu u r is bekend dat de dim ensies van de Zwin getijdengeul afnamen tijde ns de
geschiedenis (De Smet, 1940; C oornaert, 1974).
Vraag is o f d it vo or de Westerschelde ook het geval was. In Coen (2008) is verm eld dat de breedte
van de W esterscheldegeul sinds eind van de 18e eeuw niet meer veranderd is.
Dit onderzoek b e kijkt hoe vanaf 1 561 AD (Anno D om ini) to t en m et 2013 AD de dim ensies van de
Zwin en W esterscheldegeul veranderd zijn. Meer bepaald onderzoeken we hoe snel in de
geschiedenis de Zwin geul ondieper werd en versmalde. Verder w il het onderzoek bekijken o f en
hoe de dim ensies van de Westerschelde geul veranderd zijn.
Dit onderzoek b e kijkt verder o f de Westerschelde en Zwingeul in geom orfologisch evenwicht zijn.
Een getijdengeul is in geom orfologisch evenwicht ais de p lot van zijn dwarsdoorsnede versus tijslag
op een rechte valt (D’Alpaos, 2009) (zie Fig. 1).
io ’Y
107
n
o Jarrelt - No Jettes
tk Jarren • 1 Jetty
• Jarren • 2 Jettes
e Byrne et ai
a Meyor-Mora
o Seabergh et ai
i.
102
fr|m 7J
Fig. 1. Relatie tijslag-oppervlaktedw arsdoorsnede (gew ijzigd naar D'Alpaos e t al., 2009).
We veronderstellen dat de Zwin en W esterscheldegeul gedurende de geschiedenis steeds gestreefd
hebben naar d it evenwicht. De hypothese in d it onderzoek is dat een getijdensysteem dat
ingepolderd w o rd t op de volgende m anier zal reageren. Het systeem is o o rs p ro n k e lijk in evenwicht
- 137 -
en lig t (hypothetisch) in gebied 1. Als er nu ingepolderd w o rd t dan zal de tijslag verm inderen. Door
het ontpolderen is het systeem niet langer in evenwicht. De oppervlaktedoorsnede van de geul is te
g ro o t voor de gereduceerde tijslag . De enige m anier waarop het systeem terug kan in evenwicht
komen
is door de
oppervlaktedoorsnede
te
reduceren.
Na de
inpoldering
is de
oppervlaktedoorsnede van de geul verkleind met een aantal m2 die evenredig is m et de reductie in
tijslag.
Deze hypothese zal worden o nderzocht voor het Zwin en de Westerschelde.
Materiaal en methodes
Voor d it onderzoek is gebruikgem aakt van historische kaarten. Deze werden verzam eld op
verschillende locaties, w aaronder de ‘w etenschatten’ website van het VLIZ. De kaarten werden
gedigitaliseerd en in GIS verwerkt.
Om de tijsla g te kunnen berekenen vo or het hele estuarium is er nood aan topografische data van
het getijdebekken; alsook historische getijde nin fo . Deze info o ntb re e kt echter op het merendeel
van de histrorische kaarten die g e b ru ik t zijn in d it onderzoek. Ook bathym etrische data van de geul
is meestal afwezig op de kaarten. Daarom is er besloten met proxys te werken. De breedte van de
geul w o rd t g e b ru ikt ais proxy vo or de diepte. De oppervlakte van het getijdenbekken w ordt
g e b ru ikt ais pro xy vo or de tijslag.
In GIS is vo or elke kaart de oppervlakte van het getijdenbekken gem eten, ende breedte van de geul
bepaald. Deze resultaten worden dan in een gra fiek g eplot tov. de tijd .
Resultaten
De resultaten tonen aan dat de breedte van de W esterscheldegeul tussen 1795 AD en 201 3 AD licht
afnam.
De breedte van de Zwingeul nam ste rk af tussen 1561 AD en 1900 AD b lijk t u it de resultaten van
het onderzoek.
Ook werd vo or zowel de Westerschelde ais het Zwin de oppervlakte van het getijdenbekken tov. de
geulbreedte uitgezet. Dit to o n t de relatieve snelheid aan waarmee de geul versm alde ais gevolg van
een reductie in de getijdenbekken oppervlakte.
Verder
werd
voor
de
Westerschelde
en
het
Zwin
eentheoretische
tijslag
en
oppervlaktedw arsdoorsnede berekend. Dit werd gedaan door
de oppervlakte van het
getijdenbekken te verm enigvuldigen met een geschatte m inim um en m axim um tijh o o g te in het
getijdenbekken. Deze data werd dan g ep lo t tov. de data van Jarret (1976). De data van Jarret (1 976)
is een dataset die zeer vaak in de lite ra tu u r w o rd t g ebruikt.
De resultaten zijn te zien in Fig. 2 en 3.
1.00E+06
W esterschelde tijslag versus oppervlaktedoorsnede
1955 AD
1.00E+05
804 AD
1900 Al
1.00E+04
♦
1Ü0E+03
Westerschelde
20th century data
X Westerschelde
historic data
1ij|0E+02
1.00E+01
1.00E+05
1.00E+06
1,00E+Ç7s|ag (J^OOE+08
1.00E+09
1.00E+10
Fig. 2. W esterschelde oppervlaktedoorsnede versus tijsla g g e plot tov. de data van Jarret (1 976).
- 138 -
1.00E+06
Zwin tijslag versus oppervlaktedoorsnede
1.00E+05
(SI
1^0E +04
o
■U
o
AP622AD
c
-*—Zwin
l|fc)0E+03
o
tidal
prism
X Jarret
data
"D
<D
¿a
m
1lDOE+02
<D
a
a
O
1.00E+01
1.00E+04
1.00E+05
1.00E+06
1.00E+07
1.00E+08
1,00E+09|-¡js|ag(m3)
Fig. 3. Zwin oppervlaktedoorsnede versus tijsla g g e plot to v de data van Jarret (1 976).
Conclusie
Zowel het Zwin als de Westerschelde volgden in het verleden meestal de relatie zoals vooropgesteld
door D’Alpaos e t al. (2009 AD) gezien de data vaak matchen met die van Jarret (1 976). Het Zwin is
tegenw oordig (2013 AD) nog steeds niet in geom orfologisch evenwicht gezien de data ervan niet
matchen m et de p lot van de data u it Jarret (1976). De Westerschelde b lijkba ar evenmin gezien ook
hier de recente data niet matchen met die van Jarret (1976).
Referenties
Coen I. 2008. De eeuwige Schelde? Ontstaan en o ntw ikkeling van de Schelde,W aterbouwkundig
laboratorium 1 933-2008. W aterbouw kundig Laboratorium : Borgerhout, 11 2 pp.
D’Alpaos A., S. Lanzoni, M. Marani & A. Rinaldo. 2009. On the O’Brien-Jarrett-M archi law
Rendiconti lincei scienze fisiche a naturali 20. p .2 25 -2 3 6 .
Jarret J.T. 1 976. Tidal p rism -inle t area relationship. CERC-WES General Investigation o f Tidal Inlets,
Dept, o f the Arm y, US Corps o f Engineering, Report 3, p .l -32 .
Meyvis L., W. Graré and W. Dauwe. 2003. Actualisatie van het sigm aplan. W ater N ieuw sbrief 10, p .l 12
- 139 -
Selective settlem ent o f deep-sea and intertidal m eiofauna - an
experim ental approach
Mevenkamp Lisa
Vakgroep Mariene Biologie, U niversiteit Gent
S tudierichting: Marine Biodiversity and Conservation
E-mail: lisa.m evenkam p@ uqent.be
De w ereldw ijde d istrib u tie
van ta lrijke
m eiofaunale taxa w erpt vragen op over de
dispersiem echanism en van deze dieren. M eiofauna om vat kleine (32pm - 1 mm) dieren van
verschillende phyla waarvan velen geen planktonisch larvaal stadium bezitten. Dit im pliceert dat de
dispersie van m eiofauna op een vo orna m e lijk passieve m anier gebeurt en d it de belangrijkste fa cto r
is die hun d istrib u tie - en colonisatiepatroon determ ineert. De hier gepresenteerde studie
o nderzoekt het actieve gedrag van m eiofauna tijdens het bezinken in een onverstoorde w aterkolom
na resuspensie. Twee ex-situ experim enten werden uitgevoerd m et (1) m acrophyt geassocieerde
m eiofauna van een intertidaal gebied en (2) m eiofauna afkom stig van met bacteriële matten bedekt
sedim ent u it de diepzee Hàkon Mosby mud volcano (HMMV). Met zeewater gevulde tonnen (126L)
werden ais experim entele kamers g e b ru ikt en v ijf verschillende substraten, op de bodem van de
tonnen, werden aan de bezinkende meiofaunale gem eenschap aangeboden. De substraten, g e b ru ikt
in het intertidaal experim ent, waren: A gar m et bacteriën, agar m et Fucus spiralis, sulfidisch agar
m edium , ongem odificeerde agar en een lege Petri plaat. In het geval van het diepzee e xperim ent
werden azoisch sedim ent m et algen, azoisch sedim ent m et bacteriën, een sulfidisch agar m edium ,
enkel azoisch sedim ent en een lege Petri schaal g eb ru ikt. Na 12 uren werd de m eiofaunale
sam enstelling en nem atodengem eenschap op de substraten geïdentificeerd. Er werden significante
verschillen in m eiofuna densiteiten gevonden tussen de behandelingen in beide experim enten.
Nematoden en nauplius larvae vertoonden een vier keer hogere d en siteit in de Fucus behandeling
vergeleken m et de controles in het intertidaal experim ent. De diepzee nem atoden en harpacticoide
copepoden vertoonden een v ijf keer verhoogde d en siteit in het sulfide substraat vergeleken met de
controle behandelingen. De proporties van harpacticoide copepoden in het diepzee e xperim ent was
verhoogd in alle behandelingen ten opzichte van het referentiestaal. De nem atodengemeenschappen vertoonden geen significante verschillen tussen behandelingen en ten opzichte
van de referentiestalen. Deze resultaten laten blijken dat meiofaunale organism en zich selectief
kunnen bewegen in een onverstoorde w aterkolom en daarvoor a ctief to t hun dispersie op een kleine
schaal kunnen bijdragen. In beide experim enten waren de densiteiten verhoogd in substraten die
het meest op hun o o rsp ro n ke lijk habitat gelijken. Deze studie bevestigt onderzoek uit
voorafgaande studies en levert een grote bijdrage vo or het verklaren van m eiofaunale dispersie en
colonisatie.
- 140 -
Experimentele studie van het overslagdebiet voor steile hellingen en
verticale wand met zeer lage vrijb o o rd
M ollaert Justine en Sofie Peelman
Universiteit Gent, A fde lin g Weg- en W aterbouwkunde
E-mail: iustinem ollaert@ qm ail.com : sofie.peelm an@ qm ail.com
Dit artikel b esch rijft het onderzoek naar het gem iddeld golfoverslagdebiet bij structuren m et zeer
steile en verticale helling en zeer lage vrijb oo rd . Op basis van experim entele testen, uitgevoerd in
de grote g o lfg o o t van de U niversiteit Gent , is de invloed van de relevante param eters voor overslag
onderzocht. De data worden vergeleken met de reeds bestaande form ules u it de literatuur. Een
algemene u itd ru kkin g voor steile hellingen m et lage v rijb o o rd w o rd t afgeleid, inclu sie f de situatie
zonder vrijb oo rd en verticale wand.
KEYWORDS: overslag; steile helling; lage v rijb o o rd ; verticale wand.
Introductie en achtergrond
Overslag
is een
cruciaal fysisch
proces
in de
bescherm ing
tegen
overstrom ingen.
Kustw aterbouw kundige structuren worden ontw orpen vanuit esthetisch en econom isch oogpunt.
Een degelijke kennis van het overslaande volum e w ater is hierbij van g ro o t belang vo or het bepalen
van de kruinhoogte.
Ook vanuit de hernieuwbare energie sector kom t de problem atiek van overslagdebieten naar voor.
Golfenergie, de blauwe energie van toekom st, is een boom ing business. Een m anier om golfenergie
te benutten is via golfenergie-convertoren, gebaseerd op golfoverslag (OGEC). Het principe van een
OGEC is gebaseerd op golven die een talud oplopen en overslaan in een reservoir. Hierin w o rd t het
w ater gestockeerd op een grotere hoogte dan het gem iddeld w aterpeil. Vervolgens loo pt het w ater
terug naar zee via openingen in de bodem van het reservoir waarin turbines werden geplaatst. Deze
turbines wekken de e le k tric ite it op. OGEC’s worden gekenm erkt door een zeer steile helling en een
zeer lage vrijb o o rd , w at atypisch is ten opzichte van een klassieke zeewering. Een beter in z ic h t is
dan ook nodig in het overslagdebiet voor structuren m et steile helling en lage v rijb o o rd om OGEC’s
te kunnen optim aliseren.
Eerder onderzoek naar de o ptim alisatie van OGEC’s is ve rricht door V icto r (2012). Dit onderzoek
bre id t het w erk van V icto r (201 2) verder u it naar situaties zonder v rijb o o rd en verticale wand.
Vooraleerst w o rd t de gebruikte te sto pste llin g beschreven alsook de m ethodiek om de gewenste
overslagdebieten te meten. Vervolgens worden de data geanalyseerd w aarbij w o rd t gekeken naar de
invloed van de relevante param eters voor overslag. De meest bepalende param eters zijn de
spectrale g olfhoogte Hm0, de piekperiode Tp , de v rijb o o rd Rc , de hellingshoek a van de stru ctu u r
en de w aterdiepte ht aan de teen van de structuur. Deze param eters zijn visueel weergegeven in
Figuur 1.
^ .
SM.
Es
~
~ Y /
Turbine
H «,. T^.O
t
Rc
h
Figuur 1 : Relevante parameters voo r golfoverslag.
De bekomen data worden vergeleken m et voorspellingsform ules u it de bestaande literatuur. Ook
w o rd t een algemene u itd ru kkin g opgesteld vo or structuren met steile helling en lage vrijb oo rd .
Ais laatste onderdeel van d it onderzoek w o rd t de reflectie op de beschouwde s tru c tu u r bestudeerd.
Testopstelling en dataverwerking
Een te sto pste llin g gelijkaardig aan V icto r (2012) w o rd t ingebouwd in de grote g o lfg o o t van de
Universiteit Gent. Het b etreft vo or d it onderzoek een s tru c tu u r met gladde, uniform e helling. De
o pstelling w o rd t geoptim aliseerd om grote overslagdebieten op te meten. Een horizontaal voorland,
aansluitend op een geheld voorland, is aangebracht vóór het schaalm odel van de helling. De
- 141 -
stru ctu u r z e lf bestaat u it een uitneem bare houten helling en een dro og zetkuip. De d ro o g ze tku ip
bevat het reservoir, een dom pelpom p en een weegschaal.
Het opm eten van overslagvolum es gebeurt aan de hand van de variabele massa van een reservoir.
Deze techniek heeft enkele voordelen ten opzichte van het meten via drukveranderingen o f
w aterstandw ijziging. De g ebruikte techniek is m inder vatbaar voor oscillaties en is m inder
onderhevig aan de im pact van de overslagvolum es in het reservoir. Een nauwkeurigheid van
overslagdebiet van 0.0016 l/m /s kan worden bereikt.
Een schematische voorstelling van de g ebruikte te sto pste llin g en plaatsing van de apparatuur is
weergegeven in Figuur 2.
1/20
[------1------1------1
30 m
24 m
23 m
22 m 21 m
r~
20 m
3m
A r 'V H
0m
Figuur 2: Definitieschets van de testopstelling.
Om een realistische karakterisatie van golven in de Noordzee te bekomen, worden onregelm atige
golven volgens een JONSWAP spectrum m et y = 3.3 gegenereerd. Op basis van de signalen van de
golfhoogtem eters worden in WaveLab™ de invallende en reflecterende golfparam eters bepaald. Het
signaal van de weegschaal en het overslagdetectiesysteem worden geanalyseerd met behulp van
een M atlab°-script om het gem iddelde overslagdebiet te bekomen.
De te stcondities voor d it onderzoek bestaan uit een variatie van acht hellingshoeken a gaande van
25° to t 90° en zes vrijb oo rd en R tussen 0 en 7 cm. Voor de golfco nd itie s w o rd t beroep gedaan op
V ictor (2012) die zich baseert op freq ue n t voorkom ende golfco nd itie s in de Noordzee nabij
Denemarken waar OGEC prototypes werden getest. Deze testcondities leveren enkel niet-brekende
golven m et brekerparam eter ( m- lj0 > 2 . Een overzicht van de te stcondities is weergegeven in Figuur
3.
0.00,0.09 ,0 .1 8,0.27 ,0 .58,1 .0 0,1.43 , 2.14
0.000,0.005,0.010,0.020,0.045,0.070
1.022
X
1.278
0.020
0.033
X
X
0.067
X
X
X
X
X
X
0.100
0.133
0.167
0.185
1.534
1.789
2.045
X
X
X
X
X
X
Figuur 3: Testcondities van de nieuwe UG13 dataset.
Data-analyse
De data-analyse w o rd t behandeld in drie delen. Vooraleerst w o rd t het algemene geval van steile
hellingen m et helling 0 < cota < 2.14 en relatieve vrijb oo rd 0 < Rc/H m0 < 2 beschouwd. Vervolgens
w o rd t dieper ingegaan op de randgevallen zonder v rijb o o rd (Rc = 0) en verticale wand (cot a = 0).
T ot slot w o rd t de invloed besproken van de relevante param eters gevolgd door het opstellen van
een nieuwe form ule.
Algemeen geval m et positieve vrijboord
De data verkregen in d it onderzoek worden verder ais de UG1 3 dataset aangeduid. De UG1 3 dataset
w o rd t voorgesteld in Figuur 4.
- 142 -
De invloed van de param eters, behandeld d oo r V ictor (201 2), is g elijkaardig vo or zeer lage vrijb oo rd
0 < Rc/H m0 < 0.1 en zeer steile hellingen 0 < cota < 0.27. Met stijgende hellingshoek a w o rd t een
afname van het dim ensieloos gem iddeld overslagdebiet waargenomen. Voor een toenem ende
relatieve vrijb oo rd Rc/H m0 is eveneens een afname van q /ig H ^ o )0'5 merkbaar. De invloed van de
helling op het dim ensieloos gem iddeld overslagdebiet is het sterkst voor 0.27 < c o ta < 2 .1 4 e n
c
ve rd w ijn t voor cota
< 0.2. De spreiding van q /ig H ^ o )0'5 w o rd t sign ifican t voor een relatieve vrijb oo rd
g ro te r dan 0.8.
De golfperiode T en g olfste ilh eid so blijken geen sign ifican t effect te hebben op het gem iddeld
overslagdebiet. hfetzelfde w o rd t bem erkt voor de brekerparam eter f m_1 0 > 2 0 , hoewel een zeker
m axim aal overslagdebiet bereikt w o rd t vo or
lager dan 20.
R</Hm0[-]
X
U G 13 d ata c o t a = 2 .1 4
•
U G 13 d ata c o t a = 1.43
▼
U G 13 d ata c o t a = 1.00
♦
U G 13 data cot a = 0.58
■
U G 13 data cot a = 0 2 7
*
U G 13 data c o t a = 0.18
♦
U G 13 data cot a = 0.09
A
U G 13 data cot a = 0.00
¿
U G 10 data cot a = 2.14
V
U G 10 data c o t a = 1.43
□
U G 10 data cot a = 1.00
O
U G 10 data cot a = 0.58
Figuur 4: D im ensieloos gem iddeld overslagdebiet q / ( g H ?n0) 0,5 in fu n ctie van Rc/ H m0 voo r alle UG13 data samen
m et de data uit de UG10 dataset van V ictor (201 2).
In ve rg elijkin g m et de bestaande literatuur, b lijk t de fo rm u le van EurOtop (2007) [2] voor nietbrekende golven geen goede overeenkom st te geven voor steilere hellingen met cota < 1 en lage
vrijb oo rd m et Rc/H m0 < 0.5. Het dim ensieloos gem iddeld overslagdebiet w o rd t hierbij overschat
door de fo rm u le van EurOtop (2007). De form ules van V icto r (2012) geven een goede voorspelling
van het gem iddeld overslagdebiet hoewel ze voor zeer steile hellingen een onderschatting geven.
Een nieuwe u itd ru kkin g is afgeleid op basis van de vorm in ve rg elijkin g (1), naar het idee van Battjes
(1974). Het beste resultaat w o rd t bekomen voor een constante waarde voor de exponent C. Deze
waarde voor de exponent C w o rd t gelijkgesteld aan 1.3, zoals voorgesteld d oo r van der Meer en
Bruce (2013). De coëfficiënten A en B worden respectievelijk u itg e d ru k t in een lineair en
kwadratisch verband m et de helling cota. Deze verbanden zijn de best passende curven die door de
coëfficiënten A en B konden g e fit worden via regressieanalyse. De R2-waarden voor de
u itdrukkin ge n van A en B zijn respectievelijk 0.986 en 0.975 welke dus een zeer goed verband
weergeven.
De u itdrukkin ge n voor beide coëfficiënten worden weergegeven in de vergelijkingen (2) en (3),
respectievelijk. De fo rm u le is geldig voor 0 < cota < 2.14 en 0 < Rc/H m0 < 2. De rm se-waarde voor
de nieuwe u itd ru kkin g is 0.073. Dit h ou dt in dat ve rg elijkin g (1) een zeer nauwkeurige schatting
geeft van het gem iddelde overslagdebiet q /ig H ^ o )0'5-
JSlimo = 4 “ P [ - ( « ö l
(,)
A = 0.016 c o ta
B = 0.31 co t2 a
C = 1.3
(2)
(3)
(4)
+ 0.067
—1.37 c o ta + 2.94
- 143 -
In Figuur 5 w o rd t een specifieke helling m et cota = 0.09 weergegeven in com binatie m et de
vergelijking (1 ) en de toepasbare fo rm u le van V ictor (2012). Het b lijk t dat op een enkel datapunt na,
alle UG13 data gesitueerd zijn binnen het 90% betrouw baarheidsinterval van ve rg elijkin g (1 ). Ook de
onderschatting door V icto r (201 2) voor lage relatieve vrijb oo rd en is te merken in Figuur 5.
Victor (2 0 1 2 ) cot a = 0.(
E
“x
O)
Nieuw e formule cot a = 0.09
9 0 % betrouwbaarheidsinterval
U G 1 3 d ata cot a = 0.09
_ro
5
o
Td)3
T
J
■g
1e-3 -
E
ai
O)
w 1e-4
0
.S
>
(A
o
1
1e-5
Q
0.0
1.0
0.5
2.0
1.5
W .I- I
Figuur 5: D im ensieloos gem iddeld overslagdebiet q / ( g H ?n0) 0,5 in fu n ctie van de relatieve v rijb o o rd Rc/ H m0 voor
UG13 data m et c o t a = 0.09. De nieuwe ve rg elijking (1) (en 90% betrouw -baarheidsinterval) en V ictor
(2012) [1] zijn bijgevoegd.
Geval zonder vrijboord
Het randgeval van overslag zonder vrijb oo rd w o rd t eveneens apart behandeld. De relevante
param eters blijken de helling cota en in m inder mate de golfh oo gte Hm0 te zijn. Een toenem ende
Hm0en cota zorgen vo or een stijgin g in het dim ensieloos gem iddeld overslagdebiet q /ig H ^ o )0'5Wanneer de ve rg elijkin g gem aakt w o rd t tussen de UG13 data zonder v rijb o o rd en de bestaande
literatuu r, b lijk t dat de vergelijking volgens S ch üttrum pf (2001) [4] de omgekeerde trend w eergeeft
als de UG13 data wanneer q /ig H ^ o )0'5 ¡n fu nctie van
w o rd t beschouwd. Smid et al. (2001) [5]
neemt een constante waarde van 0.062 aan voor q /ig H ^ o )0'5 ¡n het specifieke geval van een
verticale wand zonder vrijb o o rd . Dit kom t goed overeen met de UG13 data vo or een verticale wand.
Er w o rd t nochtans spreiding van de UG1 3 data opgem erkt rond de constante waarde van 0.062.
De voorgestelde experim entele fo rm u le voor het geval zonder v rijb o o rd w o rd t bekomen d oo r in de
algemene ve rg elijkin g (1) de relatieve vrijb oo rd Rc/H m0 = 0 in te vullen.
- j J = = 0.016 c o ta + 0.067
Jsi/mo
(5)
De u itd ru kkin g van ve rg elijkin g (5) b lijk t v rij accuraat te zijn m et een rm se-waarde van 0.11. In
Figuur 6 is ve rg elijkin g (5) weergegeven ten opzichte van de UG13 datapunten zonder vrijb o o rd .
Het 90% betrouw baarheidsinterval is toegevoegd en geeft een beeld van de bereikte
nauwkeurigheid.
020
^
1
O)
0.18 -
O-
0 .1 6 -
a>
8
TJ
O)
0 .1 4 -
J2
0 .12 -
U G 13 data R 0 = 0 m
dim ensieloze U G 1 3 formule
9 0 % betrouwbaarheidsinterval
:)
O
g
o
(D
<5
c
«D
E
b
0.04
0.02 -
0.0
0.5
1.0
1.5
2.0
COt a [ -]
Figuur 6: D im ensieloos gem iddeld overslagdebiet q / ( g H ?n0) 0,5 in fu n ctie van de helling c o t a voo r UG1 3 data
m et v rijb o o rd g e lijk aan nui. De v e rg e lijkin g (5) en het 90% betrouw baar-heidsinterval zijn bijgevoegd.
- 144 -
Ceval m et verticale wand
Een ander randgeval is de situatie van een verticale wand. De invloed van de relevante param eters is
dezelfde ais voor het algemene geval m et positieve vrijb oo rd .
In vergelijking m et de lite ra tu u r voor cota = 0 b lijk t dat de u itdrukkin ge n volgens EurOtop (2007) en
A llsop et al. (1995) q /ig H ^ o )0'5 overschatten voor grote relatieve vrijb oo rd en en onderschat voor
kleine relatieve vrijboorden. Franco e t al. (1994) overschat het dim ensieloze gem iddeld
overslagdebiet voor de volledige range aan geteste vrijboorden. Enkel de fo rm u le van V ictor (2012)
lijk t de UG1 3 data goed te voorspellen.
Weerom w o rd t de algemene vergelijking (1) g e b ru ik t om q /ig H ^ o )0'5 te voorspellen voor cota = 0.
Een voldoende nauwkeurige vergelijking (6) w o rd t bekomen.
- ¡ J = = 0.067 e x p f - (2.94
J7T
1 v
(6)
HmoJ
J
In Figuur 7 zijn de UG13 data met verticale wand voorgesteld. De nieuwe ve rg elijkin g (6) en het 90%
betrouw baarheidsinterval zijn bijgevoegd. Uit Figuur 7 b lijk t dat verg elijkin g (6) de UG13 data zeer
goed benadert. Slechts enkele data liggen buiten het 90% betrouw baarheidsinterval. Deze
datapunten zijn uitschieters van de UG13 dataset ten gevolge van de grenzen van de te stopstelling.
Deze uitschieters komen im m ers overeen met laagst geteste golfh oo gten en overslagdebieten die
m inder nauwkeurig kunnen gem eten worden met de UG1 3 te sto pste llin g.
1e+0
•
UG131
1e-1
1e-2
1e-3
1e-4
1e-5
Q
0.0
0.5
1.0
1.5
2.0
■VH-oH
Figuur 7: D im ensieloos gem iddeld overslagdebiet q / ( g H ^ 0) 0-5 in fu n ctie van de relatieve v rijb o o rd Rc/ H m0 voor
UG13 data m et c o t a = 0. De nieuwe v e rg e lijkin g (6) en het 90% betrouw baar heidsinterval zijn
b ij gevoegd.
Reflectie
Tot slot w ordt het fenomeen van reflectie behandeld. De grootste invloed op de reflectiecoëfficiënt
K w ordt uitgeoefend door de brekerparam eter
welke een stijgende trend ve rto o n t in functie
van K.r
Wanneer de UG13 data worden vergeleken met van der Meer en Zanuttigh (2008) en Seelig en
Ahrens (1981), w o rd t een duide lijke overschatting van K d oo r de bestaande form ules opgem erkt.
V ictor (2012) geeft de beste benadering d oo r Seelig en Ahrens (1981) te com bineren m et de
reductiefactor f r 2 , gegeven door verg elijkin g (8), to t de vergelijking (7). De betrouw baarheid is
voldoende accuraat m et een rm se-waarde van 0.047.
( 7)
K r — fr,2
n. r / -^ y + o.67,
%0
fr,2
-ï.o < — < 0.9
Hr
(8)
— > 0.9
%0
- 145 -
1.4
U G 1 3 data cot a = 0.09
U G 1 3 data cot a = 0.18
U G 1 3 data cot a = 0 .27
U G 1 3 data cot a = 0.58
U G 1 3 data cot a = 1.00
U G 1 3 data cot a = 1.43
U G 1 3 data cot a = 2.14
fr 2 9 0 % betrouwbaarheidsinterval
Figuur 8: Reductiefactor f ais fu n ctie van de relatieve vrijb o o rd Rc/ H m0 voo r de UG1 3 te st data m et specifieke
helling c o ta . De red uctie fa cto r f r2 en het 90% b e tro u w b a a rh e id sin te rva l zijn bijgevoegd.
Verder onderzoek is aangewezen voor de bepaling van de reductiefactor / r2 . De fa c to r f r w ordt
voorgesteld in Figuur 8. Er w o rd t een meer gekrom de curve bem erkt in plaats van de
vereenvoudiging to t twee rechten. Deze curven vertonen een afhankelijkheid van de helling cota.
Tevens zou het lim ietgeval van een verticale wand m oeten vervat zijn in de u itd ru k k in g voor de
reflectiecoëfficiënt K w at in de huidige vorm niet m og elijk is d oo r het oneindig karakter van de
brekerparam eter ^m- lj0 vo or een verticale wand.
C o n clusie
Dit onderzoek is gerich t op de bepaling van het gem iddeld overslagdebiet voor structuren met
steile helling, inclu sie f de randgevallen zonder v rijb o o rd en verticale wand. Een algemene form ule
werd afgeleid voor het volledige bereik van vrijb oo rd en en hellingen.
Een aanbeveling w o rd t gem aakt voor verder onderzoek. Er werden enkel niet-brekende golven
getest in de UG13 dataset. Data voor brekende golven kunnen afw ijkend gedrag vertonen van de
voorgestelde form ule. Tevens heeft de gebruikte testo pste llin g zijn lim ieten, vooral betreffende de
m axim aal m ogelijke g olfhoogte. Aanpassingen aan de te sto pste llin g zijn nodig om hogere
g olfhoogten te kunnen opm eten. De fo rm u le voor de refle ctieco ëfficië nt K kan eveneens nog
aangepast worden om ook het lim ietgeval van een verticale wand te om vatten. Tenslotte w o rd t
opgem erkt dat de focus van d it onderzoek het gem iddelde overslagdebiet is maar dat ook
individuele overslagvolum es werden geregistreerd tijdens de experim entele testen. Verder
onderzoek is dan ook aangewezen om de verdeling van individuele overslagvolum es te bestuderen
voor structuren m et zeer steile helling en zeer lage vrijb o o rd .
D a n k b e tu ig in g e n
De auteurs w illen graag Prof. dr. ir. P. Troch en Dr. ir. L. V icto r bedanken voor hun hulp en
verrijkende inform atie en de technici van de A fdeling Weg- en W aterbouw kunde van de U niversiteit
Gent voor hun technische ondersteuning.
R eferen ties
A llsop W., P. Besley en L. M adurini. O vertopping perform ance o f vertical and com posite
breakwaters, seawalls and low reflection alternatives, Final MCS Project W orkshop, Alderney,
1995.
Battjes J.A. C om putation o f set-up, longshore currents, run-up and overtopping due to w in d ­
generated waves, Technical U niversity Delft, 1 974.
Franco L., M. de Gerloni enJ.W. van der Meer. Wave overtopping on vertical and com posite
breakwaters, Coastal Engineering, 1994.
Pullen T., N. Allsop, T. Bruce, A. Kortenhaus, H. S ch üttrum pf en J.W. van der Meer. EurOtop,
Technical report, EA Environm ent Agency, UK and ENW Expertise Netwerk Wate rke re n, NL and
KFKI K uratorium fü r Forschung im Küsteningenieurwesen, DE, 2007.
S ch üttrum pf H. W ellenüberlauf-ström ung bei Seedeichen Experim en-telle und Theoretische
Untersuchungen, Technical U niversity o f Braunschweig, 2001.
Seelig W. en J.P. Ahrens. Estim ation o f wave reflection and energy dissipation coefficients fo r
beaches, revetm ents and breakwaters, CERC Technical paper 81-1, Fort Belvoir, U.S.A.C.E.,
Vicksburg, MS, 1981.
- 146 -
Smid R. en H. S ch üttrum pf en J. M öller. Untersuchungen z u r Erm ittlung der m ittleren
Wellen Überlauf rate an einer senkrechten Wand und einer 1:1.5 geneigten Böschung fü r
Versuche m it und ohne Freibord (Report on small scale tests, in German), Leichtweiß Institute
fo r Hydraulics, Technical U niversity o f Braunschweig, 2001.
van der Meer J.W. en T. Bruce. New Physical Insights and Design Formulae on Wave O vertopping at
Sloping and Vertical Structures, Journal o f Waterway, Port and Ocean Engineering,
10.1 061 /(ASCE)WW.l 943 -5 46 0.00 00 22 1, 2013
V ictor L. O p tim iza tion o f the Hydrodynam ic Performance o f O vertopping Wave Energy Converters:
Experim ental Study o f O ptim al G eom etry and Probability D istrib utio n o f O vertopping Volumes,
Ghent University, 2012.
Zanuttigh B. enJ.W. van der Meer. Wave reflection fro m coastal structures in design conditions.
Coastal Engineering, Elsevier, 2008.
- 147 -
C onsum ptie van teru gg ooi d o o r zeevogels in de zuide lijke Noordzee
Sotillo Alejandro
Arsenaalstraat 40
9050 Gentbrugge; Belgium
E-mail: alexsotillo@ qm ail.com
Naast haar belang in de aanvoer van e iw itrijk voedsel voor de mens is de visserij ongew ild ook een
voedselbron voor zeevogels. Vissersvaartuigen in de Noordzee gooien een g ro o t deel van hun
vangst terug naar de zee. De meeste visserijactiviteiten in het zu id elijke Noordzee bestaan uit
sleepnetten. Hun te ru gg o oi is h oo fdza ke lijk samengesteld u it ongewervelde bodem dieren en
ondermaatse, niet-verhandelbare vis. W eggegooide vis is meestal Tong (Solea solea), Schol
(Pleuronectes platessa), Schar (Lim anda lim anda), W ijting (M erlangius m erlangus) en andere
kabeljauw achtigen. Een deel van de te ru gg o oi w o rd t v e rb ru ik t d oo r som m ige soorten zeevogels, de
zogenaam de ‘scavengers’: voorna m e lijk Zilvermeeuwen (Larus argentatus), Kleine M antelm eeuw
(Larus fuscus), Jan van Genten (M orus bassanus), Noordse Stormvogels (Fulm arus glacialis),
Drieteenmeeuwen (Rissa trida ctyla), Grote Mantelmeeuwen (Larus m arinus), Storm m eeuw (Larus
canus), en Visdiefjes (Sterna hirundo). In de vorige eeuw, zijn de lokale populaties van deze vogels
sterk gegroeid ais gevolg van een steeds toenem ende visserij en de productie van teruggooi.
In de afgelopen jaren kwam de te ru gg o oi op een keerpunt. De handhaving van het nieuwe Europese
beleid op visserijafval zal b in ne nko rt leiden to t een scherpe daling van de omvang van de
teruggooi. Waar de m ogelijke invoering van deze p o litie k ongetw ijfeld positieve effecten op de
vispopulaties beoogt, is het echter o n d u id e lijk hoe vogelpopulaties zullen reageren op de
verm indering van hun voedselaanbod.
Mei
Juli
Deze studie o nderzocht hoe
scavengers
de
teruggooi
gebruiken (consumeren), en hoe
deze a ctivite it bepalend is voor
de kw alite it en kw a n tite it van de
visserijafval die te ru g ke e rt naar
de zeebodem. Het percentage
verbruikte teruggooi, selecti­
v ite it in consum ptie, concur­
rentie en voedseldiefstal tussen
scavengers werden beoordeeld,
samen met de tem porele en
ruim telijke variatie van deze
parameters.
Juni
Twee
soorten
teruggooi
experim enten
werden
u itge ­
voerd:
‘sing le-item ’
en
gestandaardiseerde ‘ m u lti-ite m ’
experim enten.
Single-item
experim enten bestonden u it het
gooien van een item te g e lijk en
het observeren van zijn lot.
Augustus
i.5
Afstand van de kust
Fig. I . Percentage van de totale item s die werden v e rb ru ik t in
’sing le-item ’ experim enten, p e r s o o rt vis, m aand en afstand.
In m ulti-item experim enten w o rd t een fractie te ru gg o oi van bekende sam enstelling geworpen over
een vaste periode van tijd , en elke genom en item w o rd t geregistreerd. Single-item experim enten
vonden plaats van april to t augustus 2011, een dag per maand, op 2,5, 5, 10 en 20km u it de
Belgische kust. M ulti-item experim enten werden uitgevoerd in de nabijheid van de Thames Estuary,
in decem ber 2011, fe b ru a ri en april 2012.
- 148 -
Rondvis had de vo orkeu r van vogels op elke vorm van platvis, maar selectiviteit verdween tijde ns de
opfokperiode in ju n i (Fig. 1). Zilvermeeuwen verschenen achter het schip vaakst d ic h tb ij de kust,
te rw ijl Kleine Mantelmeeuwen op verdere afstanden vertoeven. Volwassen vogels verdringen de
juvenielen, die daardoor meer a fha nke lijk zijn van voedseldiefstal buiten de opfokperiode. Grotere
vogels hebben de neiging om kleinere soorten te verdringen, maar de waargenomen o ntw ikkelingen
waren niet consistent.
Deze thesis brengt aan het licht dat een grote variatie aan invloedsfactoren een belangrijke rol
speelt, en slaagt er in om aan te tonen hoe het broedseizoen en de vangstsam enstelling van de
te ru gg o oi het consum ptiepatroon van verschillende zeevogelsoorten beïnvloeden.
Ik heb twee General Linear Models gebouwd om de variatie te verklaren in het aandeel van de
geconsumeerde te ru gg o oi tijde ns m ulti-item experim enten in decem ber 2011 (Fig. 2). De gekozen
verklarende variabelen zijn de abundantie van grote meeuwen, daglicht, aanwezigheid van Jan van
Genten, en abundantie van kleine meeuwen. M ogelijke toepassingen vo or het ve rb ru ik van de
te ru gg o oi in functie van de gem eenschapsstructuur van de lokale zeevogels worden ook besproken.
p
03
O
<q
o
o
□_
o
ö
Dag, afwezigheid van Genten
Nacht, afwezigheid van Genten
Dag, aanwezigheid van Genten
50
100
150
o Dag
□ Nacht
200
Dag, afwezigheid van kleine meeuwen
Nacht, afwezigheid van kleine meeuwen
Dag, 25 kleine meeuwen
250
50
100
150
200
250
Aantal grote meeuwen
Fig. 2. Voorspelde p roporties verb ru ikte te ru gg o oi ais functie van het a a n ta l g ro te meeuwen a ch te r
het schip, zoals gedefinieerd door model 7 (a) en m odel 2 (b) voor de december-gegevens.
-149-
Het belang van de vergeten schakel: copepoden beïnvloeden de
stikstofcyclus
Stock Willem
Laboratory o f M icrobiology, P rotistology and A quatic Ecology, Marine Biology, U niversity o f Ghent
E-mail: w illem .stock@ uqent.be
In de lente van 1914 werd in het Duitse stadje Oppau de eerste fa b rie k in geb ru ik genom en die op
grote schaal am m onium kon produceren u it stikstofgas. De opening van de fa b rie k luidde het begin
in van de meest drastische im pact op de globale biochem ie ooit. Nu, net geen honderd ja a r later, is
door m enselijke activiteiten de hoeveelheid a ctief s tik s to f (N) op Aarde verdubbeld. In vele Europese
estuaria is de actieve stiksto fto evo er zelfs vertienvoudigd. Aangezien deze systemen meestal
s tik s to f g elim iteerd zijn, zijn ze b ijzo nd er gevoelig v o o re e n verhoogde N input. E utrofiëring vo rm t
tegenw oordig dan ook een belangrijk probleem in veel estuaria. Het is een com plex proces, die de
stru ctu u r van de estuariene gemeenschap sterk kan verstoren. Om de gevolgen van de verhoogde
stiksto fb elastin g te kunnen rem ediëren, is het in de eerste plaats n oodzakelijk dat we de
stikstofcyclus en de rol van aquatische organism en hierin beter begrijpen.
D enitrificatie is een essentieel proces binnen de stikstofcyclus, om dat hierdoor grote hoeveelheden
a ctief s tik s to f u it estuaria verw ijderd kunnen w orden. Het zijn vo orna m e lijk prokaryoten die tijdens
d it proces n itrie t (N 0 2-) en n itraat (NO^-) om zetten to t stikstofgas (N2) en d is tiksto fm o n o xid e (N20).
T erw ijl s tik s to f een overwegend inert gas is, is d is tiksto fm o n o xid e een potentieel broeikasgas en
mede ve ra ntw o orde lijk voor de aantasting van de ozonlaag.
Dissim ilatieve nitraatreductie naar am m onium (DNRA) is een ander nitraat-reducerend proces.
Hierbij w o rd t n itraat om gezet naar am m onium (NH4 ). Via d it anaerobe proces, w ordt, in
tegenstelling to t d en itrifica tie , de reactieve s tik s to f in het systeem behouden.
In estuaria worden DNRA en d e n itrifica tie vo orna m e lijk verw eze n lijkt door de benthische m icrobiële
gemeenschap. De bacteriën, die de reacties katalyseren, treden er bijgevolg in com petitie voor het
beschikbare nitraat en n itriet. Het belang van beide reacties is afha nke lijk van zowel
fysicochem ische ais biologische om gevingsvariabelen, die zo bepalen o f de actieve s tik s to f in het
systeem b lijft o f dat ze e ru it verw ijderd w ordt.
Vooral over de invloed van biologische interacties op de stiksto fred uctie in sedim enten is nog maar
w einig gekend. Een beperkt aantal studies toonde aan dat zowel b io turbatie (m acrofauna) ais
benthische zu urstofprod u ctie (m icrofytobenthos) een belangrijk effect kunnen hebben op
stiksto fflu xe n in estuariene sedim enten. Over het belang voor stiksto fred uctie van de m eiofauna
(m eercelligen die d oo r een 1 mm zeef gaan maar achterblijven op een 38pm zeef), het
tussenliggende trofische niveau, is am per iets gekend, en d it ondanks hun hoge abundantie en
belangrijke rol in tai van ecosysteem functies. Zo zijn het bijvoorbeeld belangrijke begrazers van
zowel bacteriën ais m icrofytobenthos.
In deze m asterproef (Willem Stock; prom otoren: Dr. Marleen De Troch, Prof. Dr. Anne W illems,
Prof. Dr. Koen Sabbe; UGent) werd het belang van de biologische interacties tussen bacteriën,
diatomeeën en m eiofauna (Copepoda, Crustacea) op de d en itrifica tie in mariene sedimenten
onderzocht. Het doei was om, vo or het eerst, de invloed van m eiofauna en hun a c tiv ite it op
den itrifica tie, een uiterm ate belangrijke ecosysteem functie, na te gaan.
Om de biologische interacties tussen diatomeeën, copepoden en bacteriën te kunnen ontrafelen
werden m icrokosm os experim enten uitgevoerd waarin ofw el (1) diatom eeën, (2) copepoden, (3)
copepoden en diatomeeën, (4) de afvalproducten van copepoden o f (5) zeewater aangerijkt met
nitraat werden toegevoegd aan het sedim ent. Er werd tevens een blanco behandeling gem aakt door
enkel g efilte rd , n a tu u rlijk zeewater aan het sedim ent toe te voegen.
Het sedim ent werd zeven en een halve dagen lang geïncubeerd. Bij het begin en op het einde van de
incubatie werden de concentraties van de nutriënten (fosfaat, am m onium , nitraat, n itrie t en silica)
bepaald. Na de incubatieperiode werd het d en itrifica tie p o te n tie e l van elke m icrokosm os bepaald.
Dit is de snelheid waarmee n itraat via d e n itrifica tie om gezet w o rd t to t d is tik s to fo x id e (N20), een
interm e dia ir in de d en itrifica tie pathway. De snelheid waarmee het nitraat v e rb ru ik t werd
(nitraatconsum ptie) is hierbij een maat voor de nitraat-reducerende a ctivite it (zowel DNRA ais
- 150 -
denitrificatie). De snelheid waarmee N20 geproduceerd werd (N20 productie) is een maat voor
den itrifica tie.
Gedurende de incubatieperiode verhoogden vooral de am m onium - en fosfaatconcentratie d oo r de
afbraak van organisch materiaal. Er was sign ifican t meer am m onium en fosfaat aanwezig in de
behandelingen m et copepoden en deze w aarbij hun afvalproducten aan toegevoegd waren.
Copepoden zorgden dus, via hun excretieproducten, voor een belangrijke toenam e van fosfaat en
am m onium , die vaak lim iterend zijn in estuaria.
Daarnaast bleken de copepoden ook een belan grijk effect te hebben op het den itrifica tiep ote n tiee l,
met name de N20 productie. De verschillen in nitraatconsum ptie tussen de verschillende
behandelingen waren veel m inder uitgesproken. Een lagere d e n itrifica tie leek dus deels
gecompenseerd te worden door een hogere DNRA activiteit.
De N20 productie was laag in de behandelingen met copepoden o f waar hun e xcretieproducten aan
toegevoegd waren. De crustaceeën hadden dus een negatieve invloed op den itrifica tie. De laagste
N20 productie werd gevonden in het sedim ent waar zowel copepoden ais diatomeeën aan waren
toegevoegd. Diatomeeën op zich bleken echter geen invloed te hebben op de N20 productie, maar
konden het negatief effect van copepoden op de gasproductie dus wel versterken. De algen vormen
een belangrijke voedselbron voor de copepoden en d oo r ze ook toe te voegen aan de m icrokosm os
werd de overleving en a ctivite it van de copepoden verhoogd.
In aanwezigheid van copepoden werd dus meer actieve s tik s to f in het systeem gehouden. Hun
excretieproducten bleken eveneens een belangrijke bron van (lim iterende) nutriënten te zijn. De
copepoden zorgden er dus vo or dat er meer vrij beschikbare nutriënten in de m icrocosm os
aanwezig waren. Deze nutriënten zijn dan beschikbaar voor diatomeeën en bacteriën en op die
m anier stim uleren de crustaceeën de groei van hun voornaam ste voedselbronnen. Deze resultaten
suggereren dat copepoden e u tro fië rin g in estuaria stim uleren om zo de hoeveelheid beschikbaar
voedsel te verhogen, doch verificatie d oo r veldm etingen b lijft noodzakelijk.
Deze resultaten tonen vo or de eerste maal aan dat m eiofauna een im pact heeft op den itrifica tie. De
vooropgestelde hypothese, waarin gesteld werd dat copepoden een effect kunnen hebben op
d en itrifica tie in marien sedim ent, werd hie rd o or bevestigd. Hoe de copepoden d it precies deden is
nog niet zeker. Belangrijke indicaties hiervoor kunnen we echter vinden in de behandeling m et hun
excretieproducten. Daar was de N20 productie eveneens laag. De excretieproducten vorm en een
belangrijke bron van k o o lsto f voor de nitraat-reducerende bacteriën. Vooral de bacteriën die aan
DNRA doen kunnen goed overweg m et een hoge k o o ls to f/s tik s to f verhouding en zullen dus
bevoordeeld worden door de e xtra koolstof. De hogere am m onium concentraties (het eindproduct
van DNRA) die in de behandelingen m et copepoden en hun afvalproducten gem eten werd, staaft
deze hypothese.
Deze thesis is een belangrijke stap voorwaarts in het beter begrijpen van de im pact van
kleinschalige biologische interacties op het functioneren van de benthische m icrobiële
gemeenschap. Het levert ons eveneens belangrijke inform atie op over het effect van de interacties
op s tiksto fflu xe n in marien sedim ent, die n oodzakelijk is, ais we de gevolgen van de grote
antropogene s tik s to f inp ut goed w illen inschatten.
- 151 -
Micro-CT ais innovatieve visualisatietechniek van m icroplastics in
mariene organism en
Van Echelpoel Wout
Laboratorium voor M ilieutoxicologie, Faculteit Bio-ingenieurswetenschappen, U niversiteit Gent
E-mail: w out.vanechelpoel@ qm ail.com
De globale plasticproductie is de afgelopen decennia enorm gestegen, nam elijk van 99 m iljoen ton
in 1989 to t 280 m iljoen ton in 2011 (PlasticsEurope, 2012), hetgeen eveneens w eerspiegeld w ordt
in een stijg in g van de proportionele plastichoeveelheid in de totale afvalstroom to t een huidig
gem iddelde van ongeveer 10% (Barnes e t al., 2009). Incorrecte verw erking, accidentele ve rspilling o f
laksheid zijn maar enkele oorzaken w aardoor plastics in het m ilieu terechtkom en, waarna tra n sp o rt
naar de oceanen plaatsvindt. Geschat w o rd t dat er zo ongeveer 10% van de totale geproduceerde
hoeveelheid plastic ja a rlijk s in de oceanen te re ch tko m t (Thompson, 2006). B lootstelling van deze
plastics aan UV-B-straling veroorzaakt m icrocracking (Andrady, 2011), hetgeen, in com binatie met
een fysische kracht (Barnes et al., 2009), leidt to t het opbreken van de plastics in steeds kleinere
com ponenten.
De
aanwezige
oceaanstrom en
transporteren
voorna m e lijk
drijvende
en
gesuspendeerde plastics met verscheidene garbage patches ais gevolg.
Een m og elijk gevolg van de aanwezigheid van deze plastics is een herverdeling van de polluenten
die in vrije vorm voorkom en in de oceanen. Dit leidt to t het instellen van een nieuw evenwicht
tussen het omgevende w ater en het plastic, m et een m ogelijkheid van opconcentratie van
polluenten aanwezig in het mariene m ilieu, w aaronder polycyclische arom atische koolw aterstoffen
(PAKs), polychlo orbife n yl (PCBs), polybro om dife nyle the rs (PBDEs), etc. (Hirai e t al., 2011 ; Mato e t al.,
2001) d oo r de hydrofobe eigenschappen van zowel het plastic ais de verb in d in g (Andrady, 2011;
Mato e t al., 2001). Deze gezam enlijke eigenschap z o rg t ervoor dat de reeds onderzochte
evenwichten tussen de vrije en geadsorbeerde hoeveelheid p olluent een gelijkaardige grootteorde
kennen ais de Kow-waarde van de p olluent in kwestie (M üller e t al., 2001). Naast deze preferentiële
adsorptie vin d t er tevens een evenw ichtsinstelling plaats van zware metalen (Ashton e t al., 2010) en
ook fo u lin g door organism en, w aaronder biofilm s, zeepokken, m ollusken en enkele anderen
(Barnes, 2002), w o rd t beschreven. In com binatie m et voorm eld tra n s p o rt ondervinden deze
hydrofobe verbindingen, zware metalen en organism en een globale verspreiding, m ogelijks zelfs to t
in Antarctica, dat m om enteel nog beschermd w o rd t door de Antarctische Stroom (Zarfl & Matthies,
2010; Barnes, 2002).
Plastic kan fragm enteren in deeltjes die kleiner zijn dan 5mm w aardoor zij m icroplastics genoemd
w orden (A rthu r et al., 2008). Deze kunnen in grote lijnen onderverdeeld worden in twee groepen,
nam elijk de prim aire en secundaire m icroplastics. De prim aire zijn voor een specifieke functie
geproduceerd en komen o.a. via huidreinigers, industriële activiteiten en accidentele ve rspilling
doorheen de zuiveringsinstallatie terecht in de rivieren (Cole e t al., 2011). De secundaire
m icroplastics worden gevorm d d oo r de geleidelijke verw ering van grotere eenheden plastic.
Doordat filte r feeders in staat zijn om m icroplastics m et m icroscopische afm etingen op te nemen
via ingestie en tra n sp o rt doorheen de darm wand (Browne e t al., 2008; Brillant & MacDonald, 2002;
von Moos e t al., 2012), bestaat er een m og elijk gevaar to t bioaccum ulatie en tra n s p o rt van
m icroplastics doorheen het voedselweb (W right e t al., 2013). In com binatie m et een m ogelijke
desorptie van geadsorbeerde polluenten kan d it een gezondheidsrisico voor vele organism en,
inclusief de mens, m et zich meebrengen.
De huidige technieken voor de visualisatie van opgenom en m icroplastics zijn zeer tijd s in te n s ie f en
voorna m e lijk d e stru ctie f van aard (Slizova e t al., 2003). Een a lte rn a tie f w o rd t gevonden bij microCT, w aarbij hoogenergetische elektrom agnetische stralen (X-stralen) g e b ru ik t worden vo or het
opbouwen van een virtueel, driedim ensionaal beeld. Door de recente verbeteringen van de resolutie
is het m og elijk geworden om het toepassingsgebied van X-stralen u it te breiden van medische CATscans naar micro- en zelfs nanom eterniveau (M izutani & Suzuki, 201 2).
Het g eb ru ik van X-stralen is gebaseerd op densiteitverschillen. Door de gelijkaardige d en siteit van
water, plastic en organisch weefsel (Davit et al., 2011) is het aangeraden om het w ater te
verw ijderen via een alcoholreeks en de m icroplastics o f het organisch weefsel te behandelen om het
contrast zo g ro o t m og elijk te maken. Hiervoor werd g eb ru ik gem aakt van a rtificiee l verzwaarde
m icroplastics (polyethyleen m et BaS04) waarmee het toepassingsgebied van deze techniek beperkt
is to t laboratorium studies.
- 152 -
Binnen het uitgevoerde onderzoek kunnen er twee belangrijke param eters geïdentificeerd worden,
met name de b lo o tste llin g d u u r en de behandeling voorafgaand aan de analyse. Wat de
b lo o tste llin g d u u r betreft, werden er drie tijdspannes gedefinieerd, zijnde ‘ k o rt’ (enkele uren),
‘ m id de llan g ’ (twee to t vier dagen) en ‘ lang’ (een week). Gedurende de korte en m iddellange periode
werden hoge plasticconcentraties g ebruikt, gaande to t 100.000 partikels per liter, te rw ijl er voor de
lange periode vo or een lagere concentratie werd gekozen, nam elijk tussen 5 en 20 partikels per
liter.
De mosselen g e b ru ikt voor de korte blootstelling werden via zure digestie behandeld (Claessens et
al., 2013), waarna d it residu g efilte rd werd over een 5pm -cellulosenitraatm em braan (Whatman,
AE98) en onder de lichtm icroscoop bestudeerd werd. Het doei was om te bepalen o f een korte
b lo otstelling reeds voldoende zou zijn voor mosselen om een consistente opnam e van m icroplastics
te vertonen. Echter, d it leidde to t een zeer beperkte consistentie in het aantal opgenom en
m icroplastics en voldeed slechts in een beperkt aantal gevallen aan het verwachte patroon, zijnde
een hogere opname bij zowel een hogere concentratie ais een langere b lootstelling. Enkele
m ogelijke oorzaken o m tre n t deze inconsistentie werden geïdentificeerd, nam elijk: de filte ra c tiv ite it,
de retentie-efficiëntie, het voedingsregim e, de onderzochte oppervlakte van de gebruikte filte r en
de densiteit van de gebruikte m icroplastics.
Het uitvoeren van de m iddellange b lo otstelling werd gevolgd door verschillende nabehandelingen
die g e b ru ikt worden voor het optim aliseren van de toestand van het weefsel voor micro-CT-analyse.
Drie verschillende technieken werden met elkaar vergeleken op basis van vier parameters:
tijd sin te n sivite it, resultaat, econom isch en m ilieuvriendelijkheid. De verschillende behandelingen
zijn: eenvoudige droging op 60 °C, behandeling met fo sfo m o lyb d ee nzu ur (PMA) en behandeling met
hexam ethyldisilazaan (HMDS). Van deze drie technieken vertoonde de HMDS-behandeling het beste
resultaat. A rtificie e l verzwaarde m icroplastics waren d u id e lijk zichtbaar in de darm en in het
weefsel.
Na bepaling van de optim ale behandeling werden mosselen gedurende m iddellange periode
blootgesteld en na afloop van deze periode onderw orpen aan twee verschillende g u t clearance
methodes: b lo otstelling gevolgd door 24 uur zonder voeding en b lo otstelling gevolgd d oo r 24 uur
zonder voeding, gevolgd d oo r 24 uur m et voeding. Via de feces kan gesteld worden dat het
toepassen van 24 uur zonder voeding, gevolgd door 24 uur m et voeding e fficiën ter is dan enkel 24
uur zonder voeding. Echter, de micro-CT-analyse to o n t reeds volledige afw ezigheid
van
m icroplastics in de darm na 24 uur zonder voeding.
De mosselen vo or de lange b lo o tste llin g d u u r werden blootgesteld aan een meer m ilieurelevante
concentratie, gedurende een langere periode. Het doei van deze langere periode was onderzoeken
o f het m og elijk is om een massabalans op te stellen en, indien m ogelijk, om d it te vereenvoudigen
door enkel g eb ru ik te maken van fecesanalyse. De bekomen massabalansen, die de m icroplastics
verdeelden over drie com partim enten, zijnde organism e, feces en water, toonden echter aan dat het
niet aan te raden is om d it te benaderen via fecesanalyse o f louter te baseren op de micro-CTbeelden. Problemen m et betrekking to t identificatie van de m icroplastics door o.a. organisch
m ateriaal en kristallisatie verhinderden een accurate kw antificatie van m icroplastics aanwezig in de
feces.
Door g eb ru ik te maken van m icro-CT ais innovatieve visualisatietechniek werd met andere woorden
aangetoond dat deze artificieel verzwaarde m icroplastics opgenom en worden d oo r de mossel,
M ytilus edulis en dat deze vervolgens translocatie in het weefsel ondergaan. Een algemene
voorbehandeling voor het verhogen van de d en siteit van het volledige m onster d ie n t hierbij nog
steeds uitgevoerd te worden, hetgeen m og elijk is m et HMDS. Zoals elke techniek w o rd t ook microCT gekenm erkt door een aantal parameters, w aaronder resolutie, instellingen en geom etrie. De
resolutie d ie nt nam elijk zo klein m og elijk te zijn om een adequate identificatie u it te voeren. De
kleine afm etingen van de g ebruikte m icroplastics (10 to t 20pm ) in com binatie m et de behaalde
resoluties (tussen 4 en 5pm) resulteerden in een beperkte o m lijn in g van de individuele deeltjes,
w aardoor sam engeklitte deeltjes gem ist kunnen worden. Kleurschakeringen kunnen ingesteld
worden in MyVGL (de software voor verw erking van de geproduceerde m icro-CT-beelden) om de
overgangsgebieden te identificeren, hetgeen een specifiek patroon d ie n t te volgen in
opeenvolgende beelden teneinde te voldoen aan de vereiste sym m etrie en geom etrie kenm erkend
voor de gebruikte sferische m icroplastics.
De opname van m icroplastics d oo r mariene organism en kan via m icro-CT op laboratorium niveau
bevestigd worden en kan leiden to t m ogelijke gevolgen zowel op een laag ais op een hoog trofisch
niveau. Gevolgen binnen het lage trofische niveau spelen zich vo orna m e lijk a f in het organism e zelf,
w aaronder opvulling van de maag en darm, verhoogde g ranulocytvorm ing en verlaging van de
lysosomale m em braanstabiliteit (von Moos e t al., 2012), hetgeen kan leiden to t vrijgave van
- 153 -
hydrolasen, gevolgd door celnecrose bij zeer hoge concentraties (Futerman & van Meer, 2004). Niet
enkel de m icroplastics z e lf kunnen leiden to t problem en, maar ook de geadsorbeerde polluenten
kunnen gevolgen hebben die vo orna m e lijk optreden na desorptie. Ook op hoger tro fis c h niveau
kunnen er gevolgen optreden van voorm elde m icroplasticopnam e, vo orna m e lijk d oo r de zure
om geving in de maag w aardoor organisch m ateriaal afgebroken w o rd t en de opgenom en
m icroplastics vervolgens vrij voorkom en in de maag. Deze vrije m icroplastics kunnen m ogelijks
doorheen de darm wand opgenom en worden, tezam en m et eventueel geadsorbeerde polluenten, die
vervolgens kunnen desorberen en doorheen het organism e getransporteerd kunnen worden.
Verder onderzoek naar het gedrag van m icroplastics in organism en alsook het gedrag van
geadsorbeerde polluenten is m et andere woorden o n o n tb e e rlijk om de volledige problem atiek in
kaart te brengen. De opvolging van geadsorbeerde polluenten w o rd t alvast voorzien d oo r de
International Pellet Watch. Echter, ook standaardisatie voor m icro plasticid en tificatie w o rd t door vele
auteurs verm eld ais een essentieel gegeven naar de to eko m st toe (Flidalgo-Ruz e t al., 2012;
Andrady, 2011; Barnes e t al., 2009; Cole et al., 2011; Shah e t al., 2008). Een zeer belangrijk
potentieel onderzoeksonderw erp b etreft de gevolgen van deze m icroplasticopnam e, meerbepaald
de weefsels waar deze partikels eventueel opgeslagen worden, de desorptiesnelheid van
geadsorbeerde polluenten in de zure om geving van de maag en de (toxicologische) gevolgen van
deze desorptie. Dit kan uitgevoerd worden op een laag trofisch niveau, maar kan eveneens
uitgevoerd worden op hoog tro fisch niveau, w aarbij men kan bepalen o f er m ogelijks
biom agnificatie in het voedselweb optreedt. Er zijn met andere woorden nog veel m ogelijkheden.
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Trofische positie van de invasieve kamkwal M nem iopsis leidyi', een
experim entele aanpak
Vanhove Brecht
Marine Biologie, Vakgroep Biologie, U niversiteit Gent
ILVO, Eenheid dier - Aquatisch m ilieu en kw aliteit, Oostende
E-mail: brecht.qp.vanhove@ qm ail.com
Inleiding
De Am erikaanse ribkw al M nemiopsis le id yi (Ctenophora, Lobata) is één van de beruchtste invasieve
soorten w ereldw ijd. Dit is te w ijten aan de succesvolle introductie via ballastw ater in de Zwarte Zee
in de jaren ’80. Het ecosysteem onderging hierdoor dram atische veranderingen. De aanwezigheid
van deze ribkw al leidde nam elijk in com binatie m et e u tro fië rin g en overbevissing to t het
ineenstorten van verschillende vispopulaties, w at grote econom ische en sociale gevolgen met zich
m eebracht voor de visserijsector. Het succes van deze soort is toe te schrijven aan de efficiëntie
waarmee ze niches in een ecosysteem kan bezetten. De hoge tolerantie ten opzichte van een breed
spectrum aan abiotische om gevingsvariabelen en de hoge snelheid waarmee ze zich kan voeden,
groeien en reproduceren werken een snelle toenam e in aantallen en g ebiedsuitbreiding in de hand.
Bijgevolg deed de observatie van deze soort in het Belgisch Deel van de Noordzee (BDNZ) in 2007,
veel vragen rijzen o m tre n t de im pact op d it ecosysteem. T rofische interacties van deze soort binnen
het voedselweb dienen onder meer te worden belicht.
Onderzoek toonde reeds aan dat deze soort zich zeer e fficië n t voedt m et verschillende
so orten /typ e s zo öplankton en op deze m anier w ed ijve rt voor voedsel m et autochtone soorten (bv.
ichthyoplankton). Eerdere studies focusten vooral op de consum ptie van zo öplankton door deze
niet-inheemse soort met behulp van voedingsexperim enten. De resultaten van deze experim enten
moeten echter met enige voorzich tig he id worden geïnterpreteerd gezien ze niet a ltijd een accurate
voorstelling van het n a tu u rlijk gedrag in het veld weergeven. Bovendien tonen klassieke
voedingsexperim enten enkel aan wat werd geconsumeerd en niet wat e ffe ctie f werd geassim ileerd.
H ierdoor kan een verkeerd beeld ontstaan rond het relatieve belang van bepaalde prooien in het
dieet. Biochemische m erkers, zoals stabiele isotopen en vetzuren geven aanvullende inform atie over
de assim ilatie over tijd . Deze technieken zijn gebaseerd op het ‘je bent w a tje e et’ principe. Hoewel
deze technieken al worden g e b ru ikt sinds de jaren ’70, w orden ze zelden g e b ru ikt in studies rond
gelatineus zoöplankton. In het algemeen is de beste benadering voor het begrijpen van trofische
interacties in een ecosysteem de integratie van verschillende technieken. Deze m asterthesis
g e b ru ikt
daarom
zowel
biochem ische
m erkers
(stabiele
isotopen
en
vetzuren)
ais
voedingsexperim enten (in clusie f aanrijkingsexperim enten l3C) om de trofische positie van M. leid yi
in het voedselweb van de zuidelijke Noordzee te onderzoeken.
Methodologie
Van ju li to t decem ber 2012 werden zes verschillende locaties in de Noordzee, havens en de
Westerschelde bem onsterd m et behulp van fijnm azig e planktonnetten. De drie voorkom ende
kamkwallen (M. leidyi, Pleurobrachia pileus en Beroe gracilis), het niet-gelatineus zo öplankton en
het fyto p la n kto n werden geselecteerd en bewaard voor stabiele isotopen analyse (k o o ls to f (C) en
s tik s to f (N)) en vetzuuranalyse. De staalnames werden zodanig gepland dat tem porele, ruim telijke
en interspecifieke variatie kon worden onderzocht. De stalen voor stabiele isotopenanalyse werden
in tinnen capsules gedroogd in het ILVO te Oostende en daarna opgestuurd naar de UC Davis stable
isotope fa c ility in Davis, C alifornia vo or de effectieve analyse m et een IRMS (‘continuous flow
isotope ratio mass sp ectrom e ter’). De kamkwallen werden eveneens g e b ru ik t voor vetzuuranalyses.
Deze werden uitgevoerd in het laboratorium van de onderzoeksgroep Mariene Biologie (UGent). Via
GC/MS (Gas C hrom atograph Mass Spectrom eter) werden totale vetzuurconcentraties bepaald en
vergeleken.
De resultaten van deze veldstudie werden aangevuld m et deze van experim enten o m tre n t de
e fficiëntie van M. leid yi ais predator (voedingsexperim enten en l3C tracer experim enten).In een
eerste reeks experim enten werd de Am erikaanse kamkwal (M. leidyi) toegevoegd aan cilinders met
verschillende prooiconcentraties van enerzijds de n a tu u rlijk voorkom ende A c a rtia sp. en anderzijds
de gekweekte A rte m ia salina. Door na 4u het aantal resterende prooien in de cilinders te tellen,
konden de ‘ Ingestion Rate’ (IR ; P rooi/uur) en ‘Clearance Rate’ (CR ; V o lum e/pred ator) worden. Op
basis van deze waarden kon de e fficiëntie van M. le id yi ais predator worden bepaald. In een tweede
reeks experim enten werden 13C aangerijkte voedselbronnen aangeboden aan M. leidyi. Twee
potentiële prooien werden geselecteerd: diatomeeën van het genus Phaeodactylum en copepoden
(A ca rtia sp.). Deze werden aangerijkt met het zware k o o ls to f isotoop, l3C, en geïncubeerd met
- 156 -
M. leid yi gedurende 3u en 6u, waarna de kam kwallen werden verw erkt voor stabiele
isotopenanalyse. Deze l3C tracer experim enten werden uitgevoerd om de assim ilatiesnelheid en
voedselselectie van M. le id yi na te gaan.
Resultaten en Discussie
Dieet en efficiëntie
Één van de redenen voor het succes van M. leid yi ais invasieve soort is het niet-selectieve dieet,
bestaande u it m esozoöplankton, ichthyoplankton en zelfs m icroplankton. Uit eerder onderzoek
bleek dat m icroplankton een belangrijke rol speelt in de ontogenetische o ntw ikke lin g van M. leid yi
en dan vooral tijd e n s de eerste levensstadia. Wanneer M. le id yi in het ‘g e lob de ’ levensstadium kom t,
verschuift het dieet naar grotere zo öplankton soorten. Het is echter m oe ilijk om het belang van
bepaalde prooien aan te tonen m et behulp van trad ition ele maaganalyses, aangezien kleine prooien
snel verteren. Via l3C tracer experim enten kan worden aangetoond o f geconsum eerd voedsel
e ffe ctie f w o rd t g e b ru ikt voor de energiehuishouding van een organism e. De experim enten
uitgevoerd binnen deze m asterthesis w ijzen erop dat volwassen (gelobde) M. le id y i specimen zich
niet voedden m et diatomeeën (Phaeodactylum sp.), maar wel m et copepoden (A c a rtia sp.; Figuur 1).
Fig. 1 :Time lapse fo to 's van M. leidyi m et consum eerde copepoden (A c a r tia sp.).
De snelheid waarmee M. le id yi d it voedsel kan verzamelen en assim ileren is o p m e rke lijk (Figuur 1).
Reeds drie uur na incubatie m et aangerijkte copepoden werd aangerijkte k o o ls to f (nC)gedetecteerd
in de lobben van M. leidyi. Vertering van prooien d u u rt gem iddeld één uur in een adulte
Am erikaanse kamkwal a fha nke lijk van de grootte van de prooien (Figuur 1). D it is consistent met
het gedrag van M. leid yi populaties in het w ild w aarbij de aanwezigheid van een grote hoeveelheid
prooien leidt to t een exponentiele expansie van de bestaande M. le id yi populaties in bepaalde
gebieden. Deze opp ortu nistische strategie bleek zeer e ffe c tie f te zijn in het verleden en zorgde
ervoor dat M. leid yi populaties autochtone soorten konden verdringen. De vetzuu rp rofie le n van M.
leid yi ondersteunen deze strategie. De totale vetzuurconcentratie van M. le id yi bleek veel m inder te
zijn dan die van de andere inheemse kamkwallen (Figuur 2). Het succes van M. le id y i ais invasieve
soort kan dus worden verklaard d oo rd at het zijn energie eerder g e b ru ikt voor snelle groei en
reproductie dan voor vetzuurreserves.
- 157 -
14000
■ DHA
g 12000
■ EPA
CuO
E ïoooo
■ ARA
M
8 0 00
■ 2 0 :lo )9
O
120:0
6 0 00
fU
g
■ 1 8 :2 w 6 (t+c)
4000
u
■ 18:10)9 (t+c)
O
2000
■ 18:0
■ 17:0
B. gracilis
M . leid yi
P. pileus
Fig. 2 : Totale vetzuurconcentraties van de drie kam kw allen
V a ria b ilite it in h e t d ie e t van M. leidyi/ R u im te lijk e , te m p o re le en in te rs p e c ifie k e p a tro n e n
Alle taxa die in deze thesis o nderzocht werden, vertoonden een d u id e lijk ru im te lijk patroon in hun
stabiele isotopensignalen. Significante verschillen werden gevonden tussen de
Westerschelde
stations en de andere stations (Noordzee en havens) voor zowel SI3C ais S^N waarden (Figuur 3). De
verklaring voor deze d ifferen tia tie in de Westerschelde lig t in het verschil in basiswaarden (baseline
values). Het preferentieel opnem en van l4N d oo r m icro-organism en in het riviergedeelte van de
schelde leidt to t verhoogde waarden voor 5I5N stroom afw aarts in de Westerschelde. De hogere
instroom van terrestrisch m ateriaal (arm er in l3C dan marien organisch m ateriaal) in de
Westerschelde verklaard eveneens de d ifferen tia tie met de mariene stations. Bovendien, werden er
geen verschillen in ve tzuu rp rofie le n opgem erkt tussen de Westerschelde en de mariene stations. Dit
is consistent m et de theorie van een baseline s h ift en to o n t dat het dieet van de kam kwallen niet
verandert in de 2 biotopen maar eerder de l3C en ,5N ra tio ’s aan de basis van het voedselweb.
Uit de analyses van de veldstalen kon ook een d u id e lijk tem poreel patroon worden geïdentificeerd
(Fig. 4). De verklaring hiervoor kan liggen in een baseline s h ift van de isotopische waarden waarbij
een onbekende abiotische variabel de C en N ra tio ’s beïnvloedt wat geobserveerd w o rd t in het
isotopisch signaal van de hogere trofische niveaus. Een tweede hypothese is een verandering in het
voedselgedrag van een lager trofisch niveau. Het is reeds gebleken u it eerder onderzoek dat
copepoden van het genus A c a rtia bij sub-optim ale condities (bv. W interm aanden) hun energie op
peil houden door kannibalism e. Deze verandering in voedselbronnen w o rd t w eerspiegelt in het
isotopisch signaal van de hogere trofische niveaus. Verder onderzoek m et meer fyto p la n kto n
replicaten is nodig om deze hypothesen te testen.
21
20
19 18
16 -
14
-23
-22
-21
-2 0
-1 9
-1 8
-17
6 13C
Fig. 3 : R uim telijke variatie voo r M. leidyi. W esterschelde stations (Zwart) en m ariene stations (Blauw).
-158-
18 -i
17 -
16 -
■ Aug
14 -
■ Nov
H r
-21
-20
-18
-17
Fig. 4: Tem porele variatie in een m arien statio n voo r M. leidyi.
Deze m asterthesis ondersteunt de positie van M. le id yi als secondaire consum ent, maar d it kon niet
worden bevestigd aan de hand van het isotopensignaal van de niet-gelatineuze zoöplanktonstalen
uit het veld. W ellicht was d it te w ijten aan het fe it dat niet-gelatineus zo öplankton in ‘ b u lk ’ werd
geanalyseerd vo or stabiele isotopen. Zoöplankton stalen zouden zich norm aal één tro fisch niveau
(~2%o vo or S^N) onder de kam kwallen moeten positioneren. De aanwezigheid van somm ige
om nivore zo öp la nkton soo rten (bv. Mysidae) en hun g ro te r aandeel d oo r biovolum e in de stalen kan
d it verklaren. Het isotopisch signaal van de inheemse kamkwal P. pileus plaatst deze ongeveer één
trofisch niveau boven M. leidyi. Deze positie suggereert dat P. pileus een andere ecologische niche
bezet dan de niet-inheemse soort M. leidyi. Dit werd reeds eerder aangehaald in de lite ra tu u r ais
m ogelijke verklaring waarom beide kamkwallen elkaar niet door m iddel van com petitie to t
uitsterven drijven. Ten slotte kon deze m asterthesis, op basis van het isotopisch signaal, B. g ra c ilis
niet identificeren ais predator van zowel P. pileus als M. leidyi, hoewel d it wel werd geobserveerd
onder laboratorium condities. U itgebreidere staalnames (meerdere keren per maand) in com binatie
m et gerichte p re d a to r/p ro o i experim enten zouden de rol van B. g ra c ilis ais predator en potentieel
controlerende fa cto r van M. le id yi populaties kunnen
Conclusie
Het gebruiken van biom erkers in com binatie m et experim entele data bewees zeer handig te zijn om
p re d a to r/p ro o i relaties te identificeren. Maar deze resultaten benadrukken tevens het belang van
tem porele, ruim telijke en m ethodologische variaties in het isotopisch signaal van organism en
wanneer data geïnterpreteerd w ordt.
Dit onderzoek bevestigt het imago van M. le id yi ais een zeer e ffic ië n t predator. Vetzuuranalyses en
experim entele data toonden dat deze invasieve kamkwal zeer snel energie u it zijn om geving kan
opnem en en zo in korte tijd enorme populaties kan vorm en. Deze o pp ortunistische strategie maakt
deze niet-inheemse soort zeer succesvol na zijn intro du ctie in een ecosysteem. De positie van M.
leid yi ais een secondaire consum ent werd door d it onderzoek ondersteund. De relatie van de nietinheemse kamkwal m et de inheemse P. pileus doet echter nieuwe vragen rijzen. Deze resultaten
lijken eerder de theorie van niche d iffe re n tia tie te bevestigen. Verder onderzoek naar de
voedselbronnen van deze soorten en de m ogelijke niche overlappingen zijn nodig in de toekom st.
Om het gevaar van M. le id yi vo or inheemse soorten te bepalen m oeten deze interacties verder
w orden uitgepluisd. Een scenario dat zich voordeed in de Zwarte Zee lijk t echter onw aarschijnlijker
in een dynamisch, open systeem ais de Noordzee. Maar blijvende eutrophicatie en overbevissing
spelen in het voordeel van deze niet-inheem se ctenophore en kunnen in de to eko m st de trofische
positie van M. leid yi derm ate versterken dat het voortbestaan van kwetsbare inheemse soorten
problem atisch w ordt.
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‘Aquacalypse N ow ’ and the end o f fish: an analysis o f instrum ents o f
sustainable fisheries in Europe
W illems Yves
Faculteit Sociale Wetenschappen, KU Leuven
E-mail: vveswillem s@ hotm ail.com
Mijn m asterpaper heeft ais tite l ‘Aquacalypse Now and the End o f Fish’: an Analysis o f Instrum ents
o f Sustainable Fisheries in Europe en werd geschreven ais eindverhandeling voor de Master o f
Science in European Politics and Policies, een m aster-na-m aster aan de fa c u lte it Sociale
Wetenschappen van de KU Leuven. Zoals de tite l reeds doet uitschijnen w o rd t er een analyse
gem aakt van de beleidsinstrum enten die g e b ru ikt worden in de EU (en meer specifiek in
Vlaanderen) om de duurzaam heid van de visserij te verhogen. Deze analyse bestaat uit vier
onderdelen, w aarbij het eerste deel de m aatschappelijke relevantie van het onderw erp schetst, het
tweede deel een theoretisch en conceptueel kader geeft w aarbinnen het onderzoek plaatsvindt, het
derde deel een overzicht geeft van het visserijbeleid van de EU en de beleidsinstrum enten die
daarbij g e b ru ikt worden en het vierde deel een analyse biedt van deze beleidsinstrum enten door op
zoek te gaan naar de voor- en nadelen van elk instrum ent. De resultaten worden afgeleid u it zowel
w etenschappelijke ais prim aire bronnen en u it interviews.
De relevantie van het onderw erp w o rd t aangetoond aan de hand van het concept ‘ tra g e d y o f the
com m ons’ zoals dat door Hardin werd uiteengezet in 1968. Hij m aakt geb ru ik van ‘com m on pool
goods’, goederen die voor iedereen beschikbaar zijn en w aarvoor niemand uitgesloten kan worden
van het g eb ru ik ervan. Het is echter zo dat com m on pool goods vaak uitputbare bronnen zijn en
indien een g ro o t aantal mensen ervoor kiest om ongereguleerd te consumeren van een com m on
pool good zou d it kunnen leiden to t een u itp u ttin g van dat goed. Dit is w at Hardin bedoelt met de
tra g e d y o f the commons. Dit concept werd vervolgens toegepast op de visserij, aan de hand van een
artikel van Sarah Kraak en een artike l van Daniel Pauly. De conclusie van deze artikels is dat de
steeds verder industrialiserende zeevisserij zou leiden to t een u itp u ttin g van de visbestanden,
indien er geen regulering zou komen. Hoewel de vissers op de lange te rm ijn zeker en vast voordeel
zouden halen om zich ze lf te lim iteren inzake de kw a n tite it van hun vangsten is er op de korte
te rm ijn een incentive om d it niet te doen. Daarom is een regulerend kader noo dza kelijk op
overheidsniveau. Dit is in de afgelopen decennia gebeurd op zowel nationaal, internationaal ais
Europees niveau. In deze m asterproef w o rd t de focus gelegd op de beleidsinstrum enten die vanuit
de EU aangereikt worden.
Voor de analyse van deze beleidsinstrum enten werd er een conceptueel en theoretisch kader
uiteengezet. Enerzijds werden enkele typologieën opgesom d die het m akkelijker zouden moeten
maken om de verschillende beleidsinstrum enten te kunnen typeren. De typologieën die g eb ru ikt
w orden zijn die van Hood (1983), Bemelmans et al. (1 998) en Salamon (2002). Verder w o rd t er ook
nog een m odel van instrum entkeuze van Eliadis, Hill & H ow lett (2005) aangehaald om een
hypothese te ontw ikkelen die lu id t ais volgt: dankzij het lage niveau van staatscapaciteit van de EU
en de hoge graad van co m p le xite it van het visserij probleem zouden de belangrijkste
beleidsinstrum enten die de EU g e b ru ikt om de duurzaam heid van haar visserij te vergroten
grotendeels bestaan uit reguleringen. Om deze instrum enten vervolgens ook nog te kunnen
evalueren werden enkele criteria aangereikt op basis waarvan een evaluatie m og elijk is. Deze zes
criteria zijn: de e ffe c tiv ite it van de geanticipeerde effecten, de aanwezigheid van eventuele
neveneffecten, de e fficiëntie van het instrum ent, de le g itim ite it van het instrum ent, de
betrokkenheid van de stakeholders en het niveau van beheersbaarheid van het instrum ent.
Na het theoretisch en conceptueel kader v o lg t een overzicht van het regelgevend kader dat de EU
vo orzie t om de duurzaam heid van de visserij in Europese wateren te vergroten. In d it overzicht
w o rd t van start gegaan m et een korte historische schets en een korte bespreking van de
hervorm ing van de Common Fisheries Policy (CFP) van 2013. De Europese Com m issie was van
m ening dat een dergelijke hervorm ing noo dza kelijk was d oordat enkele te ko rtko m in g e n van het
CFP nog niet opgelost waren. Het ging dan voorna m e lijk over de overcapaciteit van de vlo o t en het
fe it dat de naleving van de regels vrij slecht verliep. Het belangrijkste onderdeel van d it overzicht
betreft echter de beleidsinstrum enten die het onderw erp vorm en van m ijn m asterproef. Na een
analyse van de belangrijkste beleidsdocum enten en regelgeving werd besloten om te focussen op
de drie belangrijkste beleidsinstrum enten: het lim iteren van de vangst, het lim iteren van de visserijinspanning en de technische maatregelen.
- 160 -
De vangstbeperkingen zijn het belangrijkste onderdeel van de CFP. Jaarlijks worden Totaal
Toegestane Vangsten bepaald, waarop deze verdeeld worden onder de lidstaten volgens een vaste
sleutel in vangstquota. Deze quota moeten steeds gebaseerd zijn op w etenschappelijke inform atie,
vergaard d oo r nationale onderzoeksinstellingen. De m anier waarop de lidstaten deze quota
verdelen onder hun vissers w o rd t overgelaten aan de lidstaten zelf. Dit kan zowel gebeuren op
collectieve ais op individuele basis.
De beperking van de visserij-inspanning is een aanvulling op de vangstbeperkingen in die zin dat
het o ok een lim ie t bepaald van het aantal dagen dat een bepaalde boot op zee mag zijn, het aantal
boten en op de capaciteit van de boten (zowel op vlak van opslagcapaciteit ais van verm ogen). Dit
systeem w o rd t gecontroleerd via het vlo o tre g iste r en een ve rp lich t GPS systeem.
Het derde beleidsinstrum ent, de technische m aatregelen, bieden een k w a lita tie f kader om de
visserij te helpen duurzam er te worden. Er bestaan zeer veel van dergelijke maatregelen, maar de
belangrijksten zijn de m inim um m aat bij aanvoer, gesloten gebieden en visseizoenen,
m inim um m aasw ijdte van de netten en het ve rp lich t geb ru ik van selectiever vistuig. Dit allemaal
d ie nt om selectiever te vissen en bijvangsten te voorkom en.
Na een analyse naar de kenm erken van deze beleidsinstrum enten is de conclusie dat ze allen zeer
regulerend van karakter zijn, o f ‘auth ority-ba sed ’ zoals we kunnen afleiden u it de typologie van
Hood. Ook in de typologie van Salamon hebben deze beleidsinstrum enten identieke kenm erken: ze
zijn allen erg dwingend, erg d irect en weinig zichtbaar voor het publiek. De hypothese dat de
beleidsinstrum enten vooral regulerend zouden zijn w o rd t dus bevestigd. De EU hanteert een ‘ policy
m ix ’ van verscheidene beleidsinstrum enten om haar doelen te bereiken en deze zijn allen erg
regulerend. De karakteriële verschillen tussen deze beleidsinstrum enten z itte n in het fe it dat de
lim ite rin g van de vangstm ogelijkheden en van de visserij-inspanning een kw antitatieve beperking is
(waarvan de ene een beperking is op o u tp u t en de andere op input), te rw ijl de technische
maatregelen kw alitatieve beperkingen opleggen.
Volgend op de analyse naar de kernm erken van de drie beleidsinstrum enten w o rd t er overgegaan
naar de analyse naar de voor- en nadelen van elk instrum ent, aan de hand van de zes criteria die
reeds eerder besproken werden. Voor de vangstbeperkingen kunnen we concluderen dat het een
essentieel m iddel is om de ‘ race-to-fish’ te elim ineren, al vo lg t de p o litie k niet steeds de
w etenschappelijke aanbevelingen, w aardoor de e ffe c tiv ite it van het instru m e nt in gedrang kan
komen. Door ‘ h ig h -g ra d in g ’ tre e d t er echter wel een negatief neveneffect op: vissers zijn meer
geneigd om m inderwaardige vis overboord te gooien. Door het regulerend karakter van de
vangstbeperkingen kunnen we stellen dat ze een efficiënte m anier zijn om visbestanden te beheren.
Nog een voordeel van de vangstbeperkingen is dat ze voor het merendeel van de stakeholders ais
legitiem beschouwd worden. Het beheer van vangstm ogelijkheden is echter wel een stuk m oe ilijker
dan het beheer van de technische maatregelen en de beperking van de visserij-inspanning.
De e ffe ctivite it van de beperking van de visserij-inspanning is niet zo sterk als die van de
vangstbeperkingen, al is er wel vooruitgang geboekt. Een voordeel is dan weer dat er geen inherent
neveneffect verbonden is aan d it beleidsinstrum ent. Doordat er subsidies betaald dienen te worden
is d it instru m e nt d uu rd er dan de andere twee, maar d oo rd at deze subsidies wel e ffe c tie f zijn kan d it
instru m e nt toch ais e fficië n t bekeken worden. Met betrekking to t de stakeholders kunnen we
zeggen dat deze, net ais vo or de vangstbeperkingen, d it in stru m e n t ais legitiem beschouwen, mits
enig w antrouw en ten opzichte van een verdere reductie van de vlootcapaciteit. Het beheer van d it
beleidsinstrum ent is eerder gem akkelijk, mede dankzij het v lo o tre g iste r en het VMS.
Het doei van de technische maatregelen, het selectiever maken van de visserij, is deels bereikt,
w aardoor ze niet helemaal e ffe ctie f zijn. Er is vooruitgang geboekt, maar niet zoveel ais vooraf
gehoopt. Doordat de kosten erg laag zijn m oeten we ook d it instru m e nt ais e ffic ië n t bestempelen.
In tegenstelling to t de vorige twee beleidsinstrum enten z ijn de stakeholders iets argwanender ten
opzichte van de technische m aatregelen; zeker betreffende het teruggooiverbod. In vergelijking met
de andere twee beleidsinstrum enten vergen technische maatregelen maar weinig a d m in is tra tie f
werk. Het controleren van deze maatregelen is vaak echter veel m oeilijker.
Elk instru m e nt heeft dus wel zijn voor- en nadelen. Geen enkel instru m e nt is perfect in staat om de
visserij te verduurzam en. De m ix van deze instrum enten is echter belangrijk om de doelstellingen
van het CFP te kunnen bereiken. Elk instru m e nt heeft zijn pluspunten, maar het is vooral hun
co m p le m en tarite it dat voor goede resultaten kan zorgen. Zo zijn vangstbeperkingen essentieel,
maar hebben ze de technische m aatregelen om het neveneffect van de bijvangsten en de bijhorende
w eg go oip ra ktijken weg te werken. Uiteraard is er nog veel ruim te voor verbetering. De TAC zouden
meer in lijn gebracht dienen te worden met de w etenschappelijke aanbevelingen en ook het aandeel
bijvangsten in relatie met de totale vangst zou nog sterk verlaagd kunnen worden. De laatste
- 161 -
hervorm ing zou hier reeds grote stappen in kunnen verw ezenlijken. Een belangrijke fa c to r zal
echter zijn dat ook de stakeholders aan boord gehaald worden en het beleid steunen.
- 162 -
APPLICANTS
VLIZ NORTH SEA AWARD 2013
Environmental impacts o f offshore wind farm s in the Belgian part o f
the North Sea: Learning from the past to op tim ize fu tu re m o n ito rin g
program m es
Degraer Steven
Operational D irectorate Natural Environm ent, Royal Belgian Institute o f Natural Sciences, Gulledelle
100, 1200 Brussel
T h e Belgian o ffs h o re w in d fa rm m o n ito rin g p ro g ram m e
Belgium has allocated a 2 38 km 2 zone in the Belgian part o f the North Sea (BPNS) to offshore
renewable energy production, fo r exam ple offshore wind farm s. The firs t wind turbines were b u ilt in
2008. A t present (O ctober 2013), 109 tu rb ine s are operational in the BPNS. The installed wind
turbines d iffe r in fo un da tio n type and generated power: while the firs t six w ind tu rb in e s have
gra vity based fo un da tio ns (GBF), the m a jo rity are m onopiles (55) follow ed by ja c k e t fo un da tio ns
(48). The power th a t can be generated ranges between 3 and 6.1 5 m egawatt (MW) per w ind turbine.
In the next few years, several hundreds o f turbines w ill be up and running. The offshore w ind farm s
are expected to co ntribu te fo r about 43% o f the Belgian 2020 targets fo r renewable energy.
Prior to construction, a developer needs to obtain a dom ain concession and an environm ental
perm it. The latter includes a num ber o f term s and co nd itio ns to m inim ise or m itigate the
environm ental im pact o f the wind farm project. This imposes a m on itoring program m e to assess
the potential impacts on the marine environm ent. These assessments enable the auth orities to
impose m itig a tio n measures or even halt the activities in case o f extrem e damage to the marine
ecosystem. The m on itoring program m e equally allows understanding and evaluating the underlying
ecological processes in su pp ort o f an e nviro n m e nt-frien dly offshore wind farm policy and
management. The program m e started in 2005 and targets physical (hydro-geom orphology and
underw ater noise), biological (epifouling co m m un ity on the hard substratum , macro and epibenthos
o f the so ft substratum , fish, seabirds and marine m ammals), as well as socio-econom ic (seascape
perception and offshore renewables appreciation) aspects o f the marine environm ent.
The Management Unit o f the North Sea M athem atical Models (MUMM), a Scientific Service o f the
Operational D irectorate Natural Environm ent (OD Nature) o f the Royal Belgian Institute o f Natural
Sciences (RBINS) coordinates the m on itoring program m e. To cover all necessary scientific expertise
MUMM collaborates w ith several institutes: the Research Institute fo r Nature and Forest (INBO), the
Institute fo r A g ricu ltu ra l and Fisheries Research (ILVO-Bio-Environmental research group), Ghent
University (Marine Biology Research Group and INTEC), International Marine and Dredging
C onsultants (IMDC) and G rontm ij Belgium NV.
This rep ort presents an integrated overview o f all scientific fin d in g s o f the Belgian offshore wind
farm m on itoring program m e, w ith the specific aim o f drawing lessons from these fin d in g s to
optim ise fu tu re m o n itoring program m es. A series o f anticipated negative and positive im pacts are
covered, but the report also targets an insight in the underlying ecological processes. The report
fu rth e r elaborates on co nte xt setting and nuancing the results, and ends w ith some reflections to
optim ise the fu tu re m on itoring program m e.
Anticipated negative impacts
A nticipated negative impacts on the marine environm ent also affect social acceptance o f offshore
wind farm developm ents. The lack o f social acceptance is actually considered one o f the most
im p o rta n t challenges o f energy project developers w orldw ide. The social acceptance o f offshore
w ind farm s in Belgian waters was investigated th ro u g h questionnaires in 2002 and 2009, i.e. p rior
to and a fte r the firs t wind tu rb ine s had been constructed in 2008. The research dem onstrated an
increasing positive a ttitu de tow ards offshore w ind farm s w ith 68% in su pp ort o f the initiatives in
2009 versus 53% in 2002, and only 8% opponents in 2009 versus 21% in 2002. More than 90% o f
the 2009 respondents considered w ind energy to be a good alternative to non-renewable energy
sources. In Belgium, offshore w ind farm siting is socially and e nvironm entally more acceptable than
onshore w ind farm s, even when seascape is taken into account. Interestingly, g ettin g inform ed on
environm ental impacts o f offshore w ind farm s was valued highest by the public. A fo llo w up study
on social acceptance is proposed when the wind farm s closest to the coast are constructed.
A nticipated negative ecological impacts cover the risks o f increased tu rb id ity , increased sedim ent
erosion and surfacing o f the e le ctricity e x p o rt cable. Detailed m orphological investigations found
th a t increases in tu rb id ity are m ainly due to m eteorological events rather than to the construction
- 164 -
and operation o f the w ind farm s. Sedim ent erosion stayed w ithin acceptable lim its: the erosion
protection around GBFs w ind tu rb ine s functioned w ith o u t any secondary erosion, while the
m onopile erosion pits ranging fro m 2 to 6.5m were adequately confined by an erosion protection
layer. Flowever, there were substantial sedim ent losses (30 to 35%) during the dredging and
dum ping activities to install the GBFs, leaving a series o f dredging pits th a t have been refilled by
using sand from the second phase o f wind farm developm ent. Electricity e x p o rt cables fu rth e r
proved susceptible to exposure because o f the dynam ic sand dune m igration. A continued
m on itoring o f tu rb id ity using satellite images is advised. The fo llo w -u p w ith m ultibeam o f erosion
near the foundations, w ind tu rb ine sta b ility and cable burial, should be continued.
Negative impacts on seabirds th ro ug h habitat change, habitat loss, barrier-effects and collision are
m ajor environm ental concerns. While some species avoided the wind farm s (i.e. northern gannet
M orus bassanus, com m on g u ille m o t U ria aalge and razo rb ill Alca to rd a at the m ost offshore Bligh
Bank, and com m on guii Larus canus at the m ost onshore T horntonbank), o th e r species seemed to
be attracted (i.e. lesser black-backed guii Larus fuscus and herring guii Larus a rg en ta tus at the
Bligh Bank, and little guii Hydrocoloeus m inutus, great black-backed guii Larus m arinus, Sandwich
tern Sterna sandvicensis and com m on tern Sterna hirun d o at the T horntonbank). Large gulls were
often seen flyin g at ro to r height (15-22%). Based on daytim e observations, each year up to about
1300 birds, m ainly gulls, are expected to collide w ith the tu rb ine s once all w ind farm s w ill be
operational in the BPNS. D uring strong m igration periods, th ru sh Turdus spp. collisions can reach
200 victim s during a single night. Visual census com bined w ith radar observations w ill aid a fu tu re
accurate bird m o rta lity assessment. Future m on itoring o f the local seabird d is trib u tio n w ill fu rth e r
increase the likelihood o f displacem ent effect detection and w ill allow discerning possible
habituation effects.
Increased noise levels generated by w ind farm s, may harm the marine environm ent. For example,
the m axim um detected above w ater sound pressure level during pin piling activities fo r the
installation o f ja cke t foundations, reached 145 dB(A). The operational sound pressure level m ainly
generated by the blades passing th ro ug h the air, am ounted to 105-115 dB(A) at w ind speeds higher
than 12m /s and could hence be detected up to a distance o f 10km. U nderwater noise generated
during the installation o f gra vity based fo un da tio ns (about 115 dB re 1 pPa root mean square) was
close to am bient noise levels. In contrast, m onopile piling produced excessive underw ater noise
levels o f 179-194 dB re IpPa (zero to peak level at 750m), attenuating to am bient noise levels at a
distance o f up to 70km . For pin piling (jacket foundations) lower noise levels o f 1 72-1 89 dB re 1 pPa
were measured, but the to ta l num ber o f blows per m egawatt installed is 57% higher than fo r a
m onopile. When in operation, steel m onopile sound pressure is double o fth a t em itted by a jacke t
fo un da tio n tu rb ine , in its tu rn twice the sound pressure o f the background or GBF foundation
turbine. Future m on itoring w ill m ainly ta rg e t continuous underw ater noise m easurem ents, which
can be com pared w ith o the r types o f hum an-induced noise in the marine environm ent.
Piling noise in fact is a m ajor concern to marine mammals and fish. For the harbour porpoise
Phocoena phocoena occurring in Belgian waters w ith densities o f up to 2.7 in d /k m 2, aerial surveys
during a piling event showed a distance o f disturbance o f porpoises o f up to at least 20km fro m the
piling location. A m odel allowed reproducing the porpoise displacem ent in a wide area around the
piling zone, but outside th is area larger differences between the observations and the m odel were
detected. The latter d ifficu ltie s may be caused by the spatial va ria b ility in food availab ility or
seasonal movements. Further fine tu n in g and testing o f the m odel in d iffe re n t piling conditions and
based on aerial surveys and passive acoustic m on itoring data, is therefore advised. The im pact o f
construction and operational noise on fish eggs and larval developm ent in Belgian waters only
started recently, and needs more atte ntio n in the fu tu re m on itoring program m e. These ‘ passive
d rifte rs ’ cannot actively escape from the exposure to hum an-induced noise. Especially fish w ith a
swim bladder, fo r which the European sea bass D icentrarchus la b ra x w ill be used as a model
species, w ill be targeted th ro ug h an e xperim ental study.
Anticipated positive impacts
The protection against fish in g activities inside the w ind farm s is u ndoubtedly the main anticipated
positive im pact o f offshore wind farm s on the marine environm ent. Based on VMS data (Vessel
M onitoring System), it can be concluded th a t fish in g vessels - m ainly traw lers - are v irtu a lly
everywhere in Belgian waters, except in the w ind farm s. A m oderate increase in fish in g activities,
m ostly fro m Dutch fish in g vessels, is noted in the zone surrounding the w ind farm concessions.
Recreational anglers, m ostly ta rg etin g pelagic and benthopelagic fish, firs t concentrated close to
the gravity-based fo un da tio ns at the T horntonbank, but recently seem to have alm ost left the area.
Com bined w ith a possible reef effect, the exclusion o f fisheries was expected to have a sign ifican t
positive im pact on the so ft sedim ent benthos. A m acrobenthic Nephtys c irro sa co m m un ity was
found at the T ho rnto nb a nk and Gootebank, corresponding to a typical sedim entology w ith a median
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grain size between 331 pm and 410pm . The co m m un ity is dom inated by a few species, like the
polychaetes N. cirro sa and Spiophanes bombyx, the mysid shrim p Gastrosaccus s p in ife r and the
am phipod Urothoe brevicornis. A natural interannual v a ria b ility in densities between about 200 and
800 in d /m 2, was detected. While the m acrobenthic co m m un ity structure was sim ilar in the control
and concession sites before construction, sign ifican t differences were found in 2008. In th is year,
i.e. sh o rtly a fte r m ajor construction w orks, high densities (dom inated by S. bombyx) were detected.
However, no large scale effects could be detected, as the differences between co ntrol and im pact
sites disappeared again after tw o years. The Benthic Ecosystem Q uality Index (BEQI) confirm ed the
recovery o f the co m m un ity a fte r the construction works. Long term and larger-scale effects could
hence not be detected. Future m on itoring w ill focus on the fisheries exclusion and smaller-scale
enrichm ent effects, and aim at detecting these effects at the scale o f a com plete w ind farm .
Demersal fish, benthopelagic fish and epibenthos from so ft sedim ents may be p ositively impacted
as well. For exam ple, epibenthos biomass and length o f w hitin g M erlangius m erlangus slig h tly
increased at the edge o f the T horntonbank, while (tem porarily) increased abundances o f sole Solea
solea and dab Lim anda lim a n d a were observed at the edge o f the Bligh Bank. Inside the w ind farm s,
several local and tem poral impacts were detected. A t the Thorntonbank, increases in dab mean
length (2012), epibenthos biomass (2009) and num ber o f demersal fish species (2009) were
observed. A t the Bligh Bank, densities o f the com m on starfish A sterias rubens and sole increased
over the m on itoring period, and several ‘ large r’ plaice Pleuronectes platessa and tu rb o t Psetta
m axim a were noted. Some short tim e construction effects were seen sh ortly after the start o f the
p iling activities, like increased sandeel A m m odytes tobianus densities and decreased densities in
dab, o ph iu roids O phiura ophiura, squid A llo th e u tis su bu la ta and dragonet C allionym us lyra. A
continued m on itoring , ta king into account the high natural spatio-tem poral variability, w ill ensure
an increased power o f im pact detectability.
Some fish may be d ire ctly attracted to the a rtificia l hard substrata, in search fo r food or shelter. The
offshore wind tu rb in e fish co m m un ity (near the gravity-based foundations) was dom inated by
pouting Trisopterus luscus and cod Gadus m orhua, while also o the r species such as poor cod
Trisopterus m inutus, saithe Pollachius virens and black seabream Spondyliosom a cantharus were
exclusively detected close to the turbines. Cod and pouting catches were up to 12 and 30 tim es
higher, respectively, compared to the wrecks, and up to > 100 tim es higher com pared to the nearby
sandy areas. The density peaks o f both species (May-November fo r cod and September-December
fo r pouting), probably reflect a seasonal spawning m igration. Young individuals dom inated the local
cod and pouting populations. Future m on itoring w ill focus on the representativeness o f GBF wind
turbines com pared to steel m onopile turbines, the latter having a sm aller erosion protection layer
and are positioned in more offshore waters.
Fouling organism s colonising a rtificial hard substrata, increase the local species richness. D ifferent
com m unities can be detected along the depth gradient: the marine splash midge Telm atogeton
ja p o n icu s dom inated the splash zone; the intertida l fring e was characterised by barnacles and the
blue mussel M ytilus edulis', a Jassa-Tubularla-Actiniana co m m un ity in the subtidal zone was
dom inated by the am phipod Jassa h erdm an i (up to 3 105 in d ./m 2) and the hydroids Tubularia
indivisa and T. la ry n x (up to 90% coverage). The patterns in species richness, d en sity and coverage
were best illustrated at the T horntonbank, where th ey showed an increase m ainly during the firs t
tw o to three years, after which th ey stabilised. These long-term dynamics are superim posed by
seasonal dynamics w ith highest densities (generally ranging between 1-1.5 105 in d ./m 2) and
coverage (on average 60-70%) in spring and summer. In addition to the settling o f new species,
com p etitio n and predation are im p o rta n t biological processes shaping hard substrata com m unities.
Future m on itoring w ill focus on a better understanding o f the spatial heterogeneity, the dynamics
along the onshore-offshore gradient, and the use o f the a rtificia l reefs by larger invertebrates, such
as crabs and lobsters.
Understanding ecological process behind the observed impacts
A proper understanding o f the ecological processes underlying the observed impacts is
indispensable to deliver science-based advice fo r an e nviro n m e nt-frien dly design o f fu tu re wind
farm s. For exam ple, understanding the effects o f organic enrichm ent on so ft sedim ent
m acrobenthos at a small scale, allows e xtra p o la tin g these small-scale effects to large-scale and long
term impacts. Lower median grain sizes o f the sedim ent and increased organic m atter levels were
found close to the gra vity based fo un da tio ns at the Thorntonbank. These phenomena could be
linked to a m acrobenthic co m m un ity evolving away fro m the typical N. c irro s a co m m un ity in this
area. Close to the turbines, elevated m acrofaunal densities (up to 11 500 in d ./m 2), biomasses (up to
9540 m g /m 2) and num ber o f species (up to 32 spp.) were found, especially along the Northwest
and Southwest transects. Juvenile com m on starfish A. rubens, the sand mason Lanice conchilega,
the bee spionid S. bombyx, and the typical hard substrate species M onocorophium acherusicum and
J. h erdm an i tend to dom inate in th is enriched environm ent. The local enrichm ent was detectable to
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a distance o f 50m from the turbines. Future m on itoring w ill ta rg et the spatial extension o f this
effect th ro ug h tim e and at o the r types o f wind tu rb ine foundations.
Zoom ing into fish habitat use in Belgian offshore w ind farm s, m ainly young individuals o f A tla n tic
cod and pouting were clearly attracted nearby the wind turbines as was observed by divers and by
line fish in g. Demersal fish species were however not found to be consistently attracted at larger
distances (m inim um 1 80m ) from the turbines. So far, no clues o f increased recruitm ent or grow th in
demersal species were detected at larger distance. Flowever a num ber o f larger individuals o f plaice
Pleuronectes platessa were caught at the Bligh Bank. Dab on the o the r hand occurred in lower
num bers, but rem arkably had a fu lle r stomach inside (mean Fullness Index, FI: 0.15) than outside
(FI: 0.05) the area. Sim ilarly to cod, p outing showed feeding m ainly upon e pifo u lin g species, such as
J. h erdm an i and Pisidia longicornis. Cod indeed showed an attraction to the a rtificia l hard substrata
w ith about 90% o f the individuals staying w ith in a 40m range from the w ind turbines. Future
m on itoring w ill focus on a ttraction and p roduction mechanisms o the r than food availability, but w ill
also aim at including a w ider set o f fish species and an energy p ro filin g o f th e ir prey species.
Recent sightings o f European shag Phalacrocorax aristotelis, a seabird species favouring cliffs and
rocky shores, in Belgian w ind farm s and black-legged kittiw akes Rissa trid a c ty la starting to breed
on North Sea gas platform s, all p o in t tow ards the a ttra ctio n -p ro d u ctio n potential o f offshore wind
farm s fo r seabirds. W hether birds are attracted to wind farm s fro m a sheer physical p o in t o f view,
w ith the w ind farm fu n ctio n in g as a stepping stone or a resting place (attraction), or w hether they
already learned to e x p lo it the possibly increased food availab ility (production), rem ains to be
investigated. Black-legged kittiw akes were already regularly observed foraging inside the Bligh Bank
wind farm , w ith the percentage o f kittiw akes actively fo ra gin g inside the w ind farm being much
higher than in the co ntrol area (5.9% versus 0.3%). Also high num bers o f lesser black-backed gulls
were foraging close to the T ho rnto nb a nk ja c k e t foundations. Future m on itoring w ill pay atte ntio n to
the behaviour and fo ra gin g related activities o f seabirds, and to pelagic fish as the m ost im p orta nt
prey species fo r seabirds.
W ithin the a ttractio n-pro du ction debate o f offshore w ind farm s we also investigated w hether marine
mammals were attracted to the increased fish abundance close to w ind tu rb ine s or rather repulsed
by the increased noise levels. Flarbour porpoises showed an uneven sp atiotem poral d is trib u tio n in
Belgian waters, w ith a s h ift from the northern and north-eastern part o f the Belgian waters tow ards
the south-w est and west between February and A p ril. As the offshore wind farm s are relatively small
compared to the area th a t can be covered in a short tim e period by th is highly m obile species,
differences in d is trib u tio n o f h arbour porpoise w ith in and outside wind farm s are probably inferio r
to seasonal variations w ithin the southern North Sea caused by m ovements to fin d suitable prey
resources. In a dd itio n to continued aerial surveys, fu tu re m on itoring w ill ta rg et small scale passive
acoustic m on itoring (PAM) to investigate the potential use o f offshore w ind farm s by harbour
porpoises. A tte n tio n w ill also be paid to disentangle the com plex link between PAM data and
species densities.
Nuancing impact interpretation
Several impacts have been identified in the Belgian offshore w ind farm s, varying from seem ingly
negative to seem ingly positive impacts. Species richness increased because hard substrata (wind
tu rb ine fo un da tio ns and erosion protection layers) were introduced. Flowever, offshore w ind farm s
may also increase the risk o f invasions in the North Sea, as non-indigenous species (NIS) may now
fin d more suitable place to survive and hence strengthen th e ir com petitive position in the North
Sea. More than h alf o f the hard substratum inte rtid a l species (e.g. the invasive Pacific oyster
Crassostrea gigas) in the w ind farm s can be categorised as NIS. Pouting is attracted to wind farm s,
but we do not know yet w hether these offshore wind farm s act as an ecological trap. Flowever,
pouting is sig n ifica n tly larger inside than outside the w ind farm s, th e ir stomach is fille d more and
th e ir co ndition is sim ilar, so no evidence was obtained to assume th a t the habitat q u a lity o f offshore
wind farm s does not fu lfil the fu n ctio n a l needs o f pouting. Prelim inary e xtra po latio n o f bird
collisions (at North Sea population scale) to fu tu re expansions o f offshore wind farm s showed that
the e xistin g a du lt m o rta lity fo r instance o f lesser and great black-backed guii m ig h t exceed the
accepted threshold o f 5%. Future m on itoring w ill take account o f the need fo r up scaling to species
population levels and the expansion o f offshore w ind farm s in the North Sea.
Increased species richness, densities and biomass fu rth e r can be evaluated in d iffe re n t spatial
settings, fo r instance at tu rb ine level or at the level o f a wind farm or even the Belgian part o f the
North Sea. The species pool o f so ft sedim ent fish and squid did not change drastically, but the
num ber o f hard substrate associated fish species increased from 2 to 8 inside the wind farm
concession area. The num ber o f benthic species in the concession area more than doubled, fro m 91
to 264 species, since the installation o f the firs t tu rb in e foundations, m ainly because o f the increase
o f hard substratum species from 10 to 100. A u tu m n benthic biomass increased ~4000 tim es at the
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scale o f a single gra vity based fo un da tio n from 0.6kg ash-free d ry w eight (AFDW) before
construction to ~2500kg a fte r construction, w ith the m ajor part o f the biomass at the scour
protection (89%) and the intertida l M. edulis zone (10%). For the entire T ho rnto nb a nk w ind farm , the
autum n biomass increased about 14 tim es from about 5 to 70 ton AFDW. The offshore wind farm s
may co ntribu te about 3% o f the to ta l biomass in the BPNS. Future m on itoring w ill focus on a
validation o f the fo u lin g biomass estim ates fo r ja c k e t and m onopile foundations.
Reflections for an optimisation of future monitoring programmes
Six years o f m on itoring triggered a reflection on how to best continue the m o n itoring program m e,
building on both basic and targeted m on itoring contexts. The basic m on itoring should be
rationalised at the level o f the likelihood o f im pact detection, related to research e ffo rt and impact
size. The m eaningfulness o f im pact size deserves o u r atte ntio n and should be aligned w ith the
current im plem entation o f European Directives, such as the Marine Strategy Framework Directive.
Future basic m on itoring fin a lly needs to consider the representativeness o f the current fin ding s, so
fa r largely focused on GBFs. W ithin a targeted m on itoring context, the a rtificia l reef effect w ill
undoubtedly play a key role in the fu tu re m on itoring program m e. It already received a lot o f
atte ntio n in the m on itoring so far, but various cause-effect relationships, m ainly linked to the
a ttractio n-pro du ction hypothesis, remain yet to be tackled, preferably th ro ug h international
scientific collaboration. A m ajor challenge however is to achieve a reliable assessment o f cum ulative
impacts and to upscale locally observed impacts to the larger scale at which ecological processes
take place. This w ill require a close collaboration between scientists, ind ustry stakeholders and
adm inistrators, preferably across countries bordering the North Sea.
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A proposed m ethod fo r assessing the exte nt o f the seabed
sig nifican tly affected by demersal fishing in the Greater North Sea
Diesing M arkus', David Stephens, and John A ldridge
1 Centre fo r Environm ent, Fisheries and A quaculture Science, Pakefield Road,
Low estoft NR33 OHT, UK
E-mail: m arkus.diesinq@ cefas.co.uk
The widespread im pact o f b ottom tow ed fish in g gear on benthic species and com m unities has long
been recognised. The responses to a given inten sity o f fish in g disturbance can be influenced by the
e xten t to which these species and com m unities are preconditioned to disturbance by natural
processes, in particular waves and currents. The advent o f vessel m on itoring system and m odels o f
natural disturbance enable h igh-resolution and large-scale com parisons o f fish in g and natural
disturbance. Vessel m on itoring system data were em ployed to estim ate the traw led area per 12km
by 12km grid cell. We then qua ntifie d natural disturbance by estim ating the num ber o f days in a
year the seabed was disturbed by tides and waves. As natural disturbance acts on large spatial
scales, we assumed th a t each natural disturbance event affects whole grid cells. Frequencies could
thus be translated into an area o f impact, allow ing us to compare fish in g w ith natural disturbance.
We show how such com parisons can be used to estim ate the e xten t o f d iffe re n t seabed substrate
types sig n ifica n tly affected by dem ersal fishing. A measure o f the p ro b a b ility th a t fishing
disturbance exceeds natural disturbance provides one m etric fo r identifyin g areas o f sign ifican t
traw ling im pact on seabed habitats and m ig ht be used to measure progress tow ards achieving Good
Environm ental Status fo r sea-floor in te g rity w ith in the co nte xt o f the European U nion’s Marine
Strategy Framework Directive. For more than half the seabed in the English sector o f the Greater
North Sea, the results suggest th a t disturbance a ttrib utab le to dem ersal fish in g exceeds natural
disturbance based on data from the years 2006 to 2008. The imbalance between natural and fishing
disturbance is greatest in m uddy substrates and deep c irca litto ra l habitats.
Lay Summary
A ll human activities have an im pact on the environm ent, and th is is also true fo r fish in g gear th a t is
dragged over the seabed o f our continental shelves. However, it is often d iffic u lt to assess w hether
such an im pact ‘ m atters’ to the environm ent.
The significance o f b ottom -fish ing impacts depends on the nature o f the seabed habitats and the
levels o f natural seabed disturbance caused by waves and currents.
Ecological th e o ry predicts th a t animals living on and in the seabed are adapted to the naturally
occurring levels o f seabed disturbance. Shallow tide-sw ept and wave-im pacted sandy habitats
e x h ib it animal com m unities th a t are well adapted to high rates o f m o rta lity and natural disturbance.
As a consequence, these com m unities show greater resilience to fish in g disturbance as well.
Conversely, deep and stable seabed habitats are often characterised by slow -grow ing, habitatm odifying species fo r which b ottom fish in g can have m ajor and long-term im pacts on biomass and
diversity.
W hilst these relationships are relatively well understood, it remains a challenge to d ire c tly compare
seabed disturbance caused by bottom -tow ed fish in g gear w ith the natural disturbance o f the seabed
as d iffe re n t m etrics are used to measure these.
In a recent study, published in the ICES Journal o f Marine Science, Diesing et al. describe a
m ethodology th a t enables such a com parison o f fish in g and natural disturbance, based on data
from the English part o f the greater North Sea.
The presented results are particula rly relevant as th ey help id e n tify areas where fish in g disturbance
is at a level beyond the range o f natural background variability.
The proposed m ethodology m ig ht also be used to track progress tow ards Good Environm ental
Status o f sea-floor in te g rity (D escriptor 6 o f the European U nion’s Marine Strategy Framework
Directive).
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The southern North Sea? Rhine-Thames land!
Hijma Mare
Deltares, PO Box 85467, 3508 AL Utrecht, the Netherlands
E-mail: m arc.hiim a@ deltares.nl
A series o f three papers dealing w ith the closely interlinked topics o f Holocene and Pleistocene
geological evolution o f the Southern North Sea - also dubbed Rhine-Thames land - is presented
here. For th is sum m ary it is best to start w ith the paper th a t appeared last (Hijm a e t al., 2012),
which deals w ith landscape change in the last m illion years and the w ider Southern North Sea
region. To paleohum ans back then and to us modern man today, the landscape o f the North Sea
region looked vastly d iffe re n t one m illion years ago. A landbridge connected England to Belgium
and the rest o f continental Europe. Since then, however, several cycles o f m elt waters from land ice
have stripped the te rre stria l landscape o f the land bridge, allow ing the sea to enter the area in
interglacials. The paper links Q uaternary Geological research questions on tim in g and rates o f
landbridge low ering and removal to research questions in archaeology, on dispersal o f
paleohum ans fro m refugia and behavioural e volutionary adaptions to living in tem perate habitats.
Q uaternary scientists need to be able to situate a large num ber and wide variety o f observations
and fin d s fro m the North Sea in th e ir proper geological setting in ord er to translate these fin d s into
inform a tion about past landscapes and th e ir inhabitants (e.g. Gaffney et al., 2009). The North Sea
area is a critical region to answer some m ajor open questions in the fields o f palaeoanthropology
and Pleistocene studies as NW Europe was at the edge o f hom inin expansion durin g its evolutionary
stages th ro ug h the Pleistocene (e.g. Parfitt e t al., 2005; Roebroeks, 2005; Parfitt et al., 2010). As
the archaeological richness o f the Rhine-Thames part o f the North Sea is becoming more and more
evident, studies providing proper regional geological co nte xt fo r all stages o f the Palaeolithic are
needed. The increasingly larger volum es o f Pleistocene sedim ents th a t are mined from the North
Sea, in particular fo r sand extra ction , makes this even more im p orta nt. A spectacular exam ple is the
rare fin d o f a Neanderthal skull fra g m e n t fro m o ff the coast o f the Netherlands (Hublin e ta !., 2009).
C om paratively little was known about the geological setting o f the fossil. Local stratigraphical
co nte xt is m issing, and the Pleistocene landscape co nte xt is o nly known in broad and general
term s.
The Hijma e t al. (2012) paper provides a regional fram ew ork to place sites from older and younger
Palaeolithic periods in a continuous landscape e volutionary fram ew ork. The paper integrated
geological data fro m the Belgian, Dutch and British onshore and offshore, and visualizes th is fo r
critical periods as palaeogeographical scenario maps (Figures 1,2). Two o f these maps contrast the
situation in the interglacials o f the Middle Pleistocene, before and after the A nglian/E lsterian
glaciation. Before th is glaciation (in the Pleistocene up to 500,000 years ago) a wide land bridge
existed between England and Belgium even during marine highstands. The land bridge was much
narrower, but not yet fu lly removed and not yet lowered to below sea level on its northern flank, in
the interglacials o f the period a fte r 500,000 years ago, up to the Saalian glaciation (150,000 years
ago) at the end o f the M iddle Pleistocene. Erosive action by m elt w ater from th is ice age finished the
jo b o f rem oving the land bridge, and replaced it w ith an axial valley th a t connected rivers from the
North Sea to those o f the English Channel. A th ird map shows the Strait o f Dover, Southern Bight
and more n orthe rly parts o f the North Sea firs t fu lly connected durin g the sea level high stand o f
the last interglacial (Eemian, 120,000 years ago). A fo u rth maps shows the axial valley re-emerged
w ith sea level high stand o f the Last Glacial, w ith the rivers Rhine, Thames, Meuse and Scheldt all
jo in e d and routed south as the so-called Channel River. For archaeology, the differences in river
network, coastal co nfig uratio n and erosion base owing to the stage wise removal o f high stand
situations have strong archaeological im plications via (i) changes m igration routes o f herds o f
herbivores on which hom inins preyed, (ii) changes in availab ility o f flin t raw m aterials in England,
northern France and Belgium, and (iii) progressively deepening valleys and increasing loess
sedim entation changing the ways in which archeological sites fo rm and preserve (site taphonom y).
Geologically, it provides 10 cross-sections th a t allow to trace several generations o f Late Pleistocene
valley systems o f the Rhine tow ards the British-Belgian sector and the Strait o f Dover: connecting
the datable d epositional record o f the Q uaternary North Sea basin into the geom orphological
traceable record in T ertia ry and Mesozoic substrate o f the fo rm e r landbridge.
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= -1 ,0 0 0 ,0 0 0 - 50 0,00 0 yr ago
= Bavelian, Cromerian Complex
= M IS 21 , 19, 17, 15, 13 highstands
E A R L Y M ID D L E P L E IS T O C E N E
( p a la e o g e o g r a p h ic s c e n a rio )
highstand: shallow sea
lowstand: delta of
Rhine-Meuse-Thames
Figure 1. An interglacial highstand situ a tio n during
the early M iddle Pleistocene as repeatedly occurring
between 1 and 0.5 Ma (i.e. ‘Bavelian, Crom erian
C om plex'; MIS 21, 19, 17, 15, 13) showing
repeatedly glaciated headlands.
SOUTHERN NORTH SEA
Holocene drow ning o f the North Sea
The largest river in the southern North Sea is
the Rhine-Meuse system. The paper by Hijma
V.u ’ h f- r n North
coastal plain
and Cohen (2011) describes the tran sition
from Late Pleistocene valley to Holocene delta
plain o f th is system, onshore and offshore o f
the present coast. The critical period in this
tra n sitio n was the tim e between 9000 and
6000 years ago. A series o f palaeo­
geographical maps is presented, based on
w e a ld
m apping and dating at very high data
densities and com pletely covering the system
- reaching a level o f detail unsurpassed in the
H /.r.'T i
w orld. The map series shows a Rhine-MeusePalaeogeography at times of high sea level
Scheldt estuary offshore o f Rotterdam at
Uplands, valleys, coastsand shallowseas
Resistant strata
Rivers and structural _geomorphology
.. .
I
I Shalow sea and coast
I
I
ancient terraces I
1 Palaeocene marine clay / " * ■ Evident from deposits, geomorphology
9000 years, which rapidly drowns and shifts
■ ■ Active floodplainsand deltas I
I Higher uplands
I-1-!! Cretaceous chalk
. Inferred river courses
Relative young terraces
0 Early palaeolithic sites
Palaeozoic outcrop
* \ v # Cuestas, major faults, basin hinge line
landwards, loses the Scheldt as a feeding
river, starts to lose the Rhine too, develops a m uddy and organic backfill and em bryonic barrier
systems, e xpo rts sedim ent to the coastal barrier system and tid al inlets to the north o f the
drow ning estuary. A ll o f th is happens over a tim e period o f 2500 years, leading up to stabilisation
o f barrier coastal system around 6000 years ago. This resolves the transgressive stage o f coastal
evolution o f the North Sea to sim ilar level o f detail and process explanation as the later Holocene
stages. To have closed th is fo rm e r knowledge gap is especially im p o rta n t because it allows studying
landscape evolution o f the North Sea’s river valleys from the last ice age to its river m ouths and
coasts o f the Holocene in a continuum .
-".M,
.
- S y fW n lE r c
The position o f the Rhine-Meuse-Scheldt system on the wide, low -gradient continental shelf th a t the
North Sea basin provides is o f particular im portance. It has made th a t base-level changes is a
d om in a nt control on sedim entation fo r relative short periods o f tim e w ith in glacial cycles only, and
kicks in relative late in the interglacial. Plenty o f accom m odation space is left to fill by te rre stria l
deposition by rivers, and the system can be seen to go th ro ug h changes in sedim entary style in
response to hinterland clim atic changes. This holds fo r fu ll glacial co nd itio ns o f the Last Glacial
M axim um and tim es before; w ith beginning w arm ing in the Late-glacial, and w ith continued
w arm ing
o f the Early Holocene, and the later North Sea flo o r and coastal plain base overly
considerable preserved valley surface area from each o f these tim e periods.
I A T F P I F I '^ T O f 'F N F - I A ^ T F il A P IA I
L A I b K L b lb I U U b N b . L A o I L .L A U A L
( p a l a e o g e o g r a p h ic s c e n a r io )
= '8 0 -0 0 0 * 2 0,000 yr ago = last glacial until LGM
= Weichse|ian: Ear1y and Midd|e pieniglacial
= m i s 4 - 3 -2 lowstand
L ATE P L E IS T O C E N E : F IR S T 5 0,000 Y E A R S
= Eem’ )
( p a la eogeogra phic scenario )
= MIS 5e highstand; MIS 5d-a falling stage
= Last Interglacial and begin Last Glacial
SOUTHERN NORTH SEA
Saalian Drenthe
SOUTHERN NORTHSEA
E a s t A n g lia
E a s t A n g lia
/
'
B ank'S ,,
delta plain
B ro w n
J
B a n k " -.,!
since - 6 0 ka
Rhine-Meuse
Thames ____
W e a ld
W eald
:dover
STRAIT
A rto is
L-A rtois
Channel
river
A rd e n n e s
A rd e n n e s |
Eemian highstand
□
Shallowsea andcoast
■
Rrvervalleys4 deltas
PM Uplands (higher, lower)
Early Weichselianfalling stage
Resistant strata
Rivers and structural geomorphology
□
Shallowsea andcoast
B Palaeocene marine d a y /- Evident fromdeposits, geomorphology
H J Active river deltas
E 3 Cretaceouschalk
Inferred continuations I delta dnrenuons
I 1 submerged/emergingvalley
Palaeozoic outcrop \V»» cueslas' major faulls. basin hingeline
Last Glacial Rhine-Thames-Channel river and surroundings
Resistant strata
Rivers and structural geomorphology
[T~] Last-active braidplams
|-----1Uplands
p q Palaeocene marine day/— Evident fromdeposits, geomorphology
q
pieniglacial terraces, with site r j Brief ice sheet presence E 3 Cretaceous chalk
/ - Possible additional temporarypaths
Emerged seafloor and
□
Brief blocked drainage m Palaeozoc outcrop * \ * . Cuestas, may* faulls. basin hinge line
formervalleys(higher, lower)
Figure 2. Left: The highstand situa tion o f the Last Interglacial (MIS 5e) and the fa llin g stage (sub-) highstands o f
the Early W eichselian (MIS 5d-a). The map is representative fo r the lateM iddle Palaeolithic (1 3 0 -8 0 ka ago). Right:
The lowstand situ a tio n fo r thecoldest part o f the Late Pleistocene, the W eichselian Early and M iddle Pieniglacial,
up to the Last Glacial M axim um (_80-20 ka ago).
- 171 -
For the transgression, it is shown th a t the base o f the coastal prism records three stages, (i) From
the m illennium before 8.45 ka BP, deltaic flu via l environm ents o f extensive wetlands bury Lateglacial and Early Holocene valley parts, (ii) The m illennium a fte r 8.45 ka begins w ith a rapid
drow ning event. Thereafter, marked erosion in the coastal zone, an em bryonic barrier system th a t
stepped back many kilom eters, increasing tid al am plitudes in the estuaries, and bay-head delta
developm ent in upper estuarine environm ents are seen, (iii) The period between 7.5 and 6.3 ka BP
saw the Rhine step backward and d ivert away from th is fo rm e r m outh th ro u g h m ultiple avulsion,
and eventually saw the coastal barrier system stabilize its position, m arking the high stand to have
commenced.
Sea level ju m p in g 8,450 years ago
The paper by Hijma and Cohen (2010) describes the evidence fo r the pulse o f accelerated sea-level
rise th a t occurred at 8.45 ka. Both the tim in g and the m agnitude o f th is sea-level ju m p were
q uantified d irectly fro m precise sea-level data harvested from the Rhine delta. Evidence fro m
te rrestrial, glacial, and global clim ate m odel reconstructions suggests th a t th is sea-level ju m p was
caused by huge am ounts o f m eltw ater release in the fin al stages o f existence o f proglacial lake
Agassiz in North-Am erica. Drainage o f th is lake in fro n t o f the m elting Laurentide ice sheet is
nowadays w idely regarded to have caused the 8.2 ka cooling event, th a t was particularly significant
in the N orthern Hemisphere (see T örn qvist en Hijma, 201 2 fo r a recent overview). The chronology o f
the m eltw ater pulse, however, so fa r had been based on marine data o f lim ited dating accuracy,
which had placed it at ca. 8470 ± 300 yr. The data fro m Rotterdam, observed at considerable
distance fro m the release site, specify a bru p t sea-level rise to have comm enced 8450 ± 44 yr ago
and shows sea level markers fro m before and a fte r the ju m p to be separated 4 meters vertically.
Between 8500 to 8300 years ago, sea level is shown to have ju m p e d a 2.11 ± 0.89 m, in a dd itio n to
background relative sea-level rise over th a t tw o century period (1.95 ± 0.74 m). In o the r words: in
the North Sea basin, in these special centuries sea level rise was double th a t o f w hat was seen in the
centuries before and after. Considerable areas o f land transform ed to shallow sea at th is tim e. Full
marine connection between the Southern Bight and German Bight was established, and the wave
and tid al regime as we know it to da y spun up. The tem poral acceleration o f the sea-level ju m p
catalyzed these tran sfo rm atio n s from subaerial to drowned conditions. The event set back coast
lines and river m ouths, and is recorded as the transgressive surface at the base o f the Rhine-Meuse
coastal prism . Due to the event-nature o f the sea level ju m p , the dia chro ne ity o f th is transgressive
surface is stron gly suppressed in the critical area o f the later coastal zone. The fo u r meters o f very
rapid rise were follow ed by some 10 meters o f gradually decelerating fu rth e r rise in the m illen n ia which drowned the basal transgressive contact relatively deep, preserving it relative widely.
Corrected fo r g ravitational effects w ith distance to release site, the m agnitude at Rotterdam
translates to a global-averaged eustatic sea-level ju m p th a t is double the size o f previous estim ates
(3.0 ± 1.2 m versus 0 .4 -1 .4 m). The discrepancy suggests e ither a coeval A n ta rctic c o n trib u tio n or,
more likely, a previous underestim ate o f the to ta l Am erican lake drainage. Besides the global
clim atological and sea level signal links, the event is o f circum -oceanic stratigraphical relevance
deltaic and coastal successions w orldw ide, event to the e xten t th a t ju m p ’s transgressive contact is
o f use in fo rm a lly d ivid in g the Early Holocene from the Middle Holocene (Hijm a en Cohen, 2010;
Cohen en Hijma, 201 3). Reference to the sea-level acceleration results since 2010 includes the IPCC
fifth assessment report, prospection and discovery o f Early M esolithic sites below Rotterdam
harbour extension (Weerts et al., 2012), and renewed atte ntio n to the tim e-depth interval in Asian
deltas, notably th a t o f the Yangtze (Wang et al., 201 3).
C ontinuous geological coverage
The series o f papers address critical tim e-periods th a t to g e th e r describe the com ing into existence
o f the North Sea as we know it today. This provide a considerably updated fram ew ork fo r the
m acro-evolution o f the North Sea during the last m illion years. In our appreciation, o ld er macroevolutionary overviews in the past often suffered from gaps. Late Pleistocene chapters w ould cover
the glacial m axim um pre do m in an tly and Holocene chapters the last 6000 years. Early Holocene
te rre stria l co nditions were not considered to be relevant fo r sedim entation. Understanding o f the
Holocene transgression o f the North Sea was underdeveloped and projection rather than based on
mapping. The papers avoid such gaps. Clouds o f sea-level rise data were collected from before,
from durin g and from after the sea-level ju m p in the 2010 paper. The fu ll tra n sitio n from glacial
river valley, th ro u g h adaptive phases o f clim atic am elioration o f the glacial-interglacial tran sition ,
th ro ug h transgressive estuarine situations, to the eventual barrier coast and delta plain is described
as a continuous sto ry in the 2011 paper, h ig h lig h tin g aspects o f geological-geom orphological
inheritance in the developm ent besides external changes. The progressive nature o f the erosive
tran sfo rm atio n o f the Belgian-English landscape to the Southern Bight open sea is h ighlighted in the
201 2 paper.
- 172 -
Such e ffo rts enable next steps o f research, such as studying rates o f coastal processes under
considerable sea-level rise (e.g. fo r coastal geom orphologists), regional geological correlation and
com parison along the North Sea (e.g. fo r stratigraphers), and the m erging o f te rre stria l and offshore
geological fram ew orks (e.g. fo r p aleolithic archeologists). Furtherm ore, the publications have
renewed international atte ntio n fo r the Southern North Sea region as a geological reference area fo r
shelf, delta and sea-level research. Lastly, the papers contain new insights th a t are provoking and
renewing research cooperation between onshore and offshore groups from the countries around the
North Sea.
Research group acknowledgm ents
The papers fro m 2010 were part o f the Ph.D.-research o f the main applicant between 2005-2009 at
Utrecht U niversity (The Netherlands). The w ork was done in close cooperation w ith Dr. Kim Cohen
(Utrecht University; Deltares and TNO Geological Survey o f The Netherlands). The 2012 paper is the
outcom e o f a post-doctoral stay at Leiden U niversity w ith professor Wil Roebroeks, w ith Dr. Wim
W esterhoff and Dr. Freek Busschers (TNO Geological Survey o f The Netherlands) as fu rth e r
collaborators.
References
Cohen K.M. and M.P. Hijma, 201 3. The transgressive Early-Middle Holocene boundary - the case fo r
a GSSP at Rotterdam, Rhine Delta, N orth Sea Basin, STRATI 2013 1st International Congres on
Stratigraphy, Lisboa: Ciencias da Terra Universidade Nova de Lisboa: 148-49.
Gaffney V., S. Fitch and D. Smith. 2009. Europe's lost w orld: the rediscovery o f Doggerland. Council
fo r British Archeology, York.
Hijma M.P. and K.M. Cohen. 2010.Tim in g and m agnitude o f the sea-level ju m p preluding the 8200
yr event. Geology 38(3):275-278.
Hijma M.P. and K.M. Cohen. 2011. Holocene transgression o f the Rhine river m outh area, The
N etherlands/Southern North Sea: palaeogeography and sequence stratigraphy. Sedim entology
58 (6): 1453-1 485.
Hijma M.P., K.M. Cohen, W. Roebroeks, W.E. W esterhoff and F.S. Busschers. 201 2. Pleistocene RhineThames landscapes: geological background fo r hom inin occupation o f the southern North Sea
region. Journal o f Q uaternary Science 27(1 ): 1 7-39.
Hublin J.J., D. Weston, P. Gunz, M. Richards, W. Roebroeks, J. Glimmerveen and L. A nthonis. 2009.
Out o f the North Sea: the Zeeland Ridges Neandertal. Journal o f human evolution 57(6):777785.
Parfitt S.A., N.M. A shton, S.G. Lewis, R.L. Abei, G.R. Coope, M.H. Field, R. Gale, P.G. Hoare, N.R.
Larkin, M.D. Lewis, V. Karloukovski, B.A. Maher, S.M. Peglar, R.C. Preece, J.E. W hittaker and C.B.
Stringer. 2010. Early Pleistocene human occupation at the edge o f the boreal zone in northw est
Europe. Nature 466(7303):229-233.
Parfitt S.A., R.W. Barendregt, M. Breda, I. Candy, M.J. Collins, G.R. Coope, P. D urbidge, M.H. Field,
J.R. Lee, A.M. Lister, R. Mutch, K.E.H. Penkman, R.C. Preece, J. Rose, C.B. Stringer, R. Symmons,
J.E. W hittaker, J.J. Wymer and A.J. Stuart. 2005. The earliest record o f human activity in northern
Europe. Nature 438 (7070): 1008-101 2.
Roebroeks W. 2005. Life on the Costa del Cromer. Nature 438(7070):921 -922.
T örn qvist T.E. and M.P. Hijma. 201 2. Links between early Holocene ice-sheet decay, sea-level rise
and abrup t clim ate change. Nature Geoscience 5:601-606.
Wang Z., Q. Zhan, H. Long, Y. Saito, X. Gao, X. Wu, L. Li and Y. Zhao. 201 3. Early to m id-Holocene
rapid sea-level rise and coastal response on the southern Yangtze delta plain, China. Journal o f
Q uaternary Science 28:659-672.
Weerts H., A. Otte, B. Smit, P. Vos, D. Schiltmans, W. Waldus and W. Borst. 2012. Finding the Needle
in the Haystack by Using Knowledge o f M esolithic Human A daptation in a D rowning Delta.
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- 173 -
The ecology o f benthopelagic fish at offshore wind farm s - Towards
an integrated m anagem ent approach
Reubens Jan
Marine Biology Research Group, Ghent University, Krijgslaan 281/S8, 9000 Gent, Belgium
E-mail: ian.reubens@ uqent.be
The use o f wind power by m ankind has a long h istory and dates back about 3000 years in tim e. For
an extended period w ind m ills were m ainly used fo r g rind ing grain and pum ping w ater and it lasted
until 1891 before the firs t e le ctricity generating wind tu rb ine was constructed. By the end o f the
1990s, w ind energy production had become one o f the m ost im p o rta n t renewable energy resources
in the w orld. O ffshore wind farm s on the o the r hand are a relatively new concept. The firs t large
scale offshore wind farm in the w orld was b u ilt in 2000 o ff the coast o f Denmark and from th a t tim e
onwards offshore w ind power developm ent expanded rapidly. A ll across the N orth Sea wind farm s
are planned, under construction and operational. Thousands o f w ind tu rb ine s w ill be present and as
a result new hard substrate habitats, th ro u g h the w ind tu rb ine foun da tio ns, arise. In the Belgian
part o f the North Sea, the w ind tu rb ine fo un da tio ns fo rm a rtificia l reefs in a marine environm ent
fo rm e rly dom inated by a sandy seabed. These a rtific ia l reefs, the so-called w in d m ill a rtificia l reefs
(WARs) influence the ecosystem fu n ctio n in g and the local biodiversity; and interactions w ith in and
between the reef and the surrounding so ft substrate habitat w ill occur.
In th is study, we focused on the reef effects influencing benthopelagic fish in the Southern North
Sea. It is known th a t (w indm ill) a rtificia l reefs a ttract and concentrate fishes. Flowever, w hether the
fishes are m erely attracted or if production or an ecological tra p occurs is d iffic u lt to unravel. In
case o f attraction, the fish move from the surrounding environm ent tow ards the reef. They
aggregate at the reef, but there is no net increase in the local population. If production occurs, the
carrying capacity o f the environm ent increases as a result o f the new habitat. More fish are able to
settle, survive, grow and co ntribu te to the local population. The fish can also be caught in an
ecological trap, if th ey are attracted to, and preferably settle in a habitat w ith suboptim al conditions
relative to o the r available habitats. A set o f questions related to fish co m m un ity structure,
behavioural ecology and reef mechanisms involved in fish production in the specific environm ent
need to be answered to unravel the issue. Based on the outcom e o f the issue we also discussed
w hether small-scale fisheries should be allowed inside the offshore wind farm s.
From 2009 u ntil 2012 we investigated the a ttractio n-pro du ction hypothesis fo r d om in a nt fish
species related to the WARS. Inform ation on length-frequency d is trib u tio n , diet, co m m un ity
structure and m ovements o f A tla n tic cod (Cadus m orhua) and pouting ( Trisopterus luscus) was
gathered in an offshore w ind farm in the Belgian part o f the North Sea. A m ultitu de o f techniques
(i.e. visual observations w ith divers, hand line sam pling campaigns, acoustic te lem etry and stomach
content analyses) were applied and integrated to gain insights on th e ir behavioural ecology and to
unravel w hether production occurs at the WARs.
We found th a t both A tla n tic cod and p outing are stron gly attracted tow ards the WARs. Much higher
average catch rates were recorded at the WARs in com parison to the reference areas. For A tla ntic
cod average catch per unit e ffo rt was 4.6 ± 0.9 ind h 1f m 1 at the WARs, w hile it was 0.1 ± 0.03 and
1.1 ± 0.2 ind h 1f m 1fo r the sandy areas and wrecks respectively. For pouting it was 4.3 ± 0.6, 0.1 ±
0.03 and 0.7 ± 0.1 ind h 1f m 1 at the WARs, sandy areas and wrecks respectively.
A more detailed investigation o f the co m m un ity structure o f both species revealed th a t especially
younger age groups o f both species are attracted tow ards the WARs. For A tla n tic cod m ainly age
group I and II were encountered, w hile fo r pouting it was age group 0 and I. The fish are not
present th ro u g h o u t the year. There is a clear seasonal pattern in aggregation behaviour. The
highest num bers o f fish were noted during sum m er and autum n (with a mean m on thly catch rate o f
up to 13.4 and 12.8 ind h ' f m 1 fo r A tla n tic cod and pouting respectively). In w in te r tim e alm ost no
individuals were encountered. Probably m ovements related to spawning explain the seasonality in
presence at the WARs.
Further, we dem onstrated that, during the period they were present near the WARs, A tla n tic cod
e xhibited strong residency and high site fid e lity. Most o f the tagged fish were present on a daily
basis fo r 75% o f the tim e o f the m on itoring period.
- 174 -
Stomach content analyses revealed th a t both A tla n tic cod and pouting fed on the epifaunal species
present at the WARs. The d om in a nt prey species in the d ie t o f pouting were Jassa herdm ani, Pisidia
longicornis, Pisces sp. and Liocarcinus spp. In the d ie t o f A tla n tic cod J. herdm ani, P. longicornis,
Liocarcinus spp., Necora puber, and Pisces sp. were m ost dom inant. Some am phipod species (i.e.
Phtisica m a rin a and M onocorophium acherusicum ) had a high frequency o f occurrence as well and
reached high abundances, but co ntribu te d less to the to ta l prey biomass fo r both species. The
p redom inant prey species in the d ie t were all present in high densities at the WARs.
To acquire more inform a tion on the q ua lity o f the food, energy p ro filin g o f both fish species was
perform ed. The fishes had more energy available than required to m aintain th e ir m etabolism . Thus,
enough energy was left fo r grow th and reproduction. As a result the WARs are considered a suitable
feeding ground w ith sufficient, good q u a lity food available. In addition, the fitness o f pouting and
A tla n tic cod was com pared between the WARs and the reference areas. No sign ifican t differences in
fitness were found, indicating the WARs are not in fe rio r in q u a lity to the reference habitats. Based
on the integrated results it was concluded th a t production occurs on a local scale (i.e. at the WARs).
However, so fa r no changes in p ro d u ctiv ity were observed on a regional scale.
The results obtained during th is study allowed to describe the life -h is to ry o f A tla n tic cod and
pouting at the WARs. The age group I A tla n tic cod arrive at the WARs in April-M ay. They feed on the
epifaunal prey species present, grow and stay in the area u n til the end o f the year. By w in te r m ost Igroup individuals have left the WARs and only few specimens come back after the spawning period.
For pouting the O-group arrives at the WARs in September and feeds on the epifaunal prey species.
They leave the area by January but by May the l-group is back at the WARS and stay again u ntil the
end o f the year. D uring th is period feeding and grow th are observed.
The offshore wind farm s in the Belgian part o f the North Sea are closed to fisheries. However,
pressure groups aim ing at the fa c ilita tio n o f passive fisheries inside the wind farm concession
areas, are active in Belgium. Based on the current knowledge on the ecology and population
structuring o f A tla n tic cod and pouting at the WARs, we conclude th a t no fisheries activities should
be allowed inside the offshore wind farm s in the Belgian part o f the North Sea. We su pp ort this
statem ent w ith several argum ents: 1) no indication o f regional production was observed yet; 2)
juvenile fish dom inated the catches; 3) there is a seasonal pattern in presence and 4) fisheries
exclusion areas w ill benefit both fish populations and fisheries.
In conclusion, we dem onstrated th a t WARS influence the behavioural ecology o f A tla n tic cod and
pouting. They benefit from these a rtific ia l hard substrates and thrive well in th is environm ent closed
to fisheries. We su pp ort th is fisheries closure, because the benefits are exported beyond the
boundaries o f the wind farm concession since the fish leave the protective area once th ey grow
older. Proper management, th ro u g h w e ll-th o u g h t-o u t marine spatial planning and regulations,
should be im plem ented to reduce conflicts and use the marine resources in a sustainable way.
- 175 -
Impact o f beach no urishm e nt on coastal ecosystems w ith
recom m endations fo r coastal policy in Belgium
Vanden Eede Sarah
Marine Biology Research Group, Ghent University, Krijgslaan 281/S8, 9000 Gent, Belgium
E-mail: vanden.eede.sarah@ qmail.com
Sandy shores or beaches line 70% o f the w o rld ’s oceans, including the entire Belgian coastline. They
have a m ultitu de o f ecosystem fu nctio ns, co nstitu te an im p o rta n t habitat fo r a variety o f fauna and
flo ra and hold im p o rta n t econom ic, social and cultural value as prime recreational assets.
Predictions on sea level rise, intensified storm s, accelerated erosion and flo od risk fo r the North Sea
have led to the d ra fting o f the Belgian Integrated Coastal Safety Plan. In order to protect the Belgian
coastline on a short and long term basis (up to 2050), the Belgian sandy beaches face a m ultitu de o f
beach nourishm ent activities over the next years. This soft coastal defence measure safeguards the
natural dynamics o f the coast and has little im pact on the beach ecology and to u rism com pared to
o the r options. However, to g e th e r w ith the m ultitu de o f human beach functions, beach nourishm ent
pote ntia lly threatens the natural balance o f the beach and coastal ecosystem.
In th is PhD thesis, 16 Belgian beaches, sampled over 14 years, were analysed in o rd er to understand
the natural va ria b ility o f th is sandy beach ecosystem. By means o f m on itoring the ecological beach
nourishm ent on the Belgian beach o f Lom bardsijde, possible im pact effects were unraveled. The
com bination o f mesocosm experim ents and both m odeling and biological valuation techniques gave
valuable insights into more ecologically adjusted beach nourishm ents. As m anagem ent o f the
coastal zone is clearly a m ulti-faceted and com plex endeavour, where the interests o f several
stakeholders need to be com bined, coastal m anagem ent desperately needs ecological dim ensions.
The gathered scientific knowledge fro m m on itoring data, experim ents, biological valuation maps
and m odel predictions is used to provide guidelines fo r ecologically good practice o f beach
nourishm ent, m on itoring protocols and decision su pp ort to ols fo r m anaging the Belgian beach
ecosystem in a sustainable way.
This PhD research has been prom oted by Prof. Dr. Magda Vincx and Prof. Dr. Steven Degraer. Sarah
Vanden Eede is trained as a b io lo g ist (Master in Biology) and as a marine b io lo g ist (Master in Marine
and Lacustrine Sciences). Financial su pp ort was provided by Vlaamse overheid, Agentschap voor
Maritiem e D ienstverlening en Kust, A fde lin g Kust and Ghent University. The thesis has been
subm itted in partial fu lfilm e n t o f the requirem ents fo r the degree o f D octor in Science, Marine
Sciences.
- 176 -
Development o f physiologically based pharm acokinetic models fo r
the bioaccum ulation o f persistent organic po llutan ts in marine
mammals
Weijs Liesbeth
Systemic Physiological and Ecotoxicological Research (SPHERE), D epartm ent o f Biology, U niversity o f
Antw erp, G roenenborgerlaan 171, 2020 Antw erpen, Belgium
E-mail: liesbeth.weiis@ uantwerpen.be
Factors, such as a greater demand fo r products and more sophisticated industrial techniques, have
caused a grow ing num ber o f chemicals in the environm ent. Due to a lack o f e ffic ie n t m etabolic
breakdown or e lim in a tion processes in organism s and in the environm ent, these chemicals can be
passed on in the aquatic and te rre stria l food webs leading to higher levels in the predator compared
to its prey. Marine mammals are apex predators in marine ecosystems and as such, th e y accum ulate
considerable am ounts o f chemicals th ro u g h th e ir diet. Evidence in the literature has shown th a t
these am ounts can have a m ajor negative im pact on th e ir im m une, endocrine and reproductive
system or even on th e ir survival in general. Marine mammals do not seem to have the appropriate
enzyme systems to be able to deal w ith chemicals. They experience the negative effects o f p ollution
them selves and at the same tim e, pass the chemicals on to th e ir o ffsp ring . As a consequence, levels
o f contam inants in these animals decrease o nly slow ly even th ough the industrial production o f
several chemicals has been restricted or banned in the past.
In order to prevent repetitions o f past situations, it is im p o rta n t to gain knowledge about the
absorption, d is trib u tio n and e lim in a tion o f known or ‘o ld ’ chemicals in marine mammals.
Understanding the kinetics and effects o f old chem icals can be useful to assess the im pact o f new
chemicals w ith com parable properties com pared to the old ones before these new chemicals are
being m anufactured. From th is p oint o f view, studying known, old chem icals is u ndoubtedly useful
fo r the risk assessment o f new com pounds.
In th is thesis, the kinetics o f known or tra d itio n a l chemicals such as PCBs and PBDEs, was
investigated in h arbour porpoises and long-finned p ilo t whales by using physiologically based
pharm acokinetic (PBPK) models. These com puterized m odels com bine physiological inform a tion o f
the organism o f interest and chem ical properties o f the chemical o f interest to reflect the kinetics o f
th a t com pound in the body o f the organism . Sim ilar to exposure experim ents in which all factors
are controlled to m inim ize the large degree o f va riability, m odels fo r w ild populations are also more
reliable if the datasets used fo r evaluation o f the m odels are som ewhat ‘ ro b u s t’ or ‘ u n ifo rm ’. For
practical reasons, trends are easier to visualize and param eters are easier to estim ate if the num ber
o f interfering , external factors are reduced to a m inim um . For theoretical reasons, scattered data
can lead to param eter estim ates th a t are not reflecting the intrinsic, physiological capabilities o f the
species.
Consequently, it was im p o rta n t to investigate firs t which factors were influencing the levels o f
pollutants in the blood since blood is the o nly circulation m edium in the models. Blood samples o f
harbour seals and porpoises o f d iffe re n t health condition, o rig in (captivity versus w ild), gender and
age were analysed. Results showed th a t o nly emaciated animals had deviating concentrations and
profiles o f PCBs and PBDEs in th e ir blood com pared to animals th a t were not emaciated. O f course,
starvation can occur in w ild populations, but is d e fin ite ly not com m on fo r all w ild animals. The
conclusion here was thus th a t datasets o f blood could be used in the bioaccum ulation models.
However, blood is never sampled at the same tim e as tissues in marine mammals. In m ulticom partm ental models as the ones developed in th is w ork, data o f more tissues was preferred to
evaluate the m odel predictions fo r as much com partm ents as possible sim ultaneously.
Because the Black Sea harbour porpoise dataset was both restricted in tim e (animals were from
1997-1998) and space (animals from the Black Sea do not leave the Black Sea area), these results
were preferably used to evaluate the very firs t prelim inary harbour porpoise m odel predictions.
These m odels were developed to explain the bioaccum ulation o f several PCB congeners (PCB 153,
PCB 180, PCB 101, PCB 149, PCB 118, PCB 99, PCB 170) and PBDE congeners (PBDE 47, PBDE 99,
PBDE 100 and PBDE 153) in male harbour porpoises. Model outp uts showed th a t levels o f all PCBs
and PBDEs reached high levels at the end o f lactation period (e.g. firs t year o f life) a fte r which the
grow th d ilu tio n effect and a change in d iet caused a decline in concentrations follow ed by an
increase in concentrations fo r the rest o f the lives o f the Black Sea harbour porpoises. The models
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were then applied to assess tem poral trends by using the dataset o f harbour porpoises fro m the
North Sea. D uring th is m odelling exercise, levels o f PCBs and PBDEs were found to decrease from
1990 u ntil 2008, although not at the same rate fo r all PCB and PBDE congeners. For some PCB
congeners, the PBPK models were also used to test the m etabolic bio tran sfo rm atio n capacity fo r PCB
11 8, PCB 149 and PCB 101. Results suggested a fa irly weak m etabolic breakdown o f PCB 118 and
an enhanced capacity fo r m etabolic breakdown o f PCB 101 w ith higher age. In contrast, results were
inconclusive about the m etabolic capacities fo r PCB 149. So far, all a ttem pts to estim ate parameters
were perform ed m anually and the se nsitivity o f the param eters on the m odel o u tp u t was tested by a
‘one-at-a-tim e’ o r local se nsitivity analysis. However, th is type o f sensitivity analysis ignores
potential correlations between the parameters. Hence, more sta tistically sound param eter
estim ation m ethods and global sensitivity tests th a t take into account potential interactions
between the param eters were needed in order to im prove the robustness o f the models.
A pplying new m ethods fo r param eter estim ation and sensitivity analyses was, thus, the next step.
So, in the m ost recent PBPK m odel fo r bioaccum ulation o f pesticides (p ,p ’-DDT, p ,p ’-DDE, p ,p ’-DDD)
in h arbour porpoises, param eters were estim ated using Bayes’ theorem executed w ith M arkov chain
Monte Carlo (MCMC) sim ulations. In addition, the influence o f changes in param eter values on the
m odel o u tp u t was tested using global sensitivity analyses. Com pared to all previous PBPK models,
th is m odel fo r bioaccum ulation o f pesticides differed not o nly in the statistical techniques, but also
in its com plexity. Whereas all previous models showed the kinetics o f a single com pound, the
pesticide model showed the kinetics o f p ,p ’-DDT and its tw o m etabolites p ,p ’-DDE and p ,p ’-DDD at
the same tim e ensuring a high co nn ectivity between the kinetics o f these three com pounds. Similar
to the previous harbour porpoise models, the structural model was firs t evaluated using a dataset o f
harbour porpoises from the Black Sea a fte r which the param eter range estim ates were fu rth e r
o ptim ize d using the dataset o f harbour porpoises fro m the North Sea.
The same techniques (Bayesian PBPK m odelling and MCMC sim ulations) were also used fo r a PBPK
model fo r the lifetim e bioaccum ulation o f PCB 1 53 in long-finned p ilo t whales. For th is species, tw o
datasets were available from tw o mass stranding events. Long-finned p ilo t whales have tig h t fa m ily
group bonds so whenever an individual ends up on the beach, all o th e r m em bers o f the group
follow . For the animals, these mass strandings are traum atic, but th ey are a great o p p o rtu n ity fo r
m on itoring and m odelling as a dataset cannot possibly be more ‘ hom ogeneous’. In contrast to the
dataset o f the Black Sea harbour porpoises, o nly blubber samples were available fo r the long-finned
p ilo t whales. The PBPK m odels fo r the bioaccum ulation o f PCB 153 in p ilo t whales are therefore
sm aller than the models in harbour porpoises. Nevertheless, param eters were estim ated w ith the
m ost suitable technique fo r th is type o f models, m aking the p ilo t whale m odel already a useful
fram e w o rk fo r evaluating sim ilar o r more elaborate datasets in the future.
This w ork provides new ideas and innovative approaches to study b io m o n itorin g data. The
bioaccum ulation m odels developed here can already be used as a fram e w o rk to compare to new
datasets, but can also be fu rth e r o ptim ize d and expanded in the fu tu re . These results are,
therefore, not o nly a useful addition to e xistin g knowledge, but provide also new perspectives to
assess p ollutio n and its effects in marine mammals. Such an integrated approach is required to set
up guidelines fo r conservation o f a species. As a result, the m odels developed in th is w ork are
undoubtedly useful to ols fo r risk assessment purposes.
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