KEOPS
Bacterial Production, Bacterial activity, Protozoa - META DATA
October 2005
Parameters no :
151 – Rosette – Bacteria (production)
92– Rosette – Bacteria (ectoenzymatic activity)
–
– heterotrophic and autotrophic nanoflagellates enumeration
438 Nanoflagellates Heterotrophic HNAN
Living organisms
(Abundance)
439 Nanoflagellates Heterotrophic HNAN
Living organisms
(Abundance)
440 Nanoflagellates Heterotrophic HNAN
Living organisms
(Biomass)
441 Nanoflagellates Heterotrophic HNAN
Living organisms
(Biomass)
442 Nanoflagellates Autotrophic PNAN
Living organisms
(Abundance)
443 Nanoflagellates Autotrophic PNAN
Living organisms
(Abundance)
444 Nanoflagellates Autotrophic PNAN
Living organisms
(Biomass)
445 Nanoflagellates Autotrophic PNAN (Biomass) Living organisms
446 Ciliates (abundance)
447 Ciliates (biomass)
448 Bacterial grazing
449 Phytoplankton (Nano-) (grazing)
Living organisms
Living organisms
Living organisms
Living organisms
Epifluorescence
stock Rosette
Microscopy
Epifluorescence Microscopy stock Experimentation
Biovolume estimation, C
conversion
Biovolume estimation, C
conversion
Epifluorescence
Microscopy
Epifluorescence Microscopy
stock Rosette
Biovolume estimation, C
conversion
Biovolume estimation, C
conversion
Inverted microscopy
C conversion factors
Fluorescence labelled preys
Fluorescence labelled preys
stock Rosette
stock Experimentation
stock Rosette
stock Experimentation
stock Experimentation
stock
stock
flux
flux
Rosette
Rosette
Rosette
Rosette
Project Title: Bacterial Production, Bacterial activity, Protozoa
Name: Urania Christaki (responsible person), France Van Wambeke
Address: Université du Littoral Côte d'Opale, Maison de la Recherche en Environnement
Naturel (MREN), 32 avenue Foch, 62930 Wimereux
e-mail: Urania.Christaki@mren2.univ-littoral.fr
Overview of the project: Effects of natural and experimental effects of iron fertilization
on Bacterial Production, Bacterial ecto-enzymatic activity, Protozoan abundance and
biomass, grazing activities.
Data description
Parameters and methodology:
1) along ctd profiles
Bacterial production was measured by [3H]leucine technique using the microcentrifuge protocol (specific activity: 160 Ci mmol-1; final concentration 20 nM).
Ectoenzymatic activity. Bacterial ectoenzymatic activity (aminopeptidase,
phosphatase, alpha- and beta- glucosidase) was measured on-board through the
hydrolysis rates of fluorogenic substrates. Concentration kinetics were realized on surface
layers at stations A3 and C11.
Heterotrophic nanoflagellates (HNAN), autotrophic nanoflagellates (PNAN) and
ciliates. The enumeration of HNAN are performed with an epifluorescence microscope
upon return to the laboratory.
Grazing Fluxes. Grazing of bacteria and nanophytoplankton by heterotrophic
nanoflagellates and ciliates, respectively, was measured using fluorescent labelled preys
during short term grazing experiments within surface samples. The grazing rates will be
estimated using prey ingested per unit time.
2) OBEX experiments
Bacterial production, ectoenzymatic activities, HNAN and PNAN abundances
were also determined during three OBEX experiments : 2 in A3 station and 1 in C11
station.
Sampling strategy: Samples for bacterial production were collected throughout
the water column (0 – 200m) along 25 profiles and 7 to 8 depths per profile between 0
and 200m during the KEOPS cruise. Bacterial enzymatic activity and grazing were
measured in surface samples of the station A3 and C11. Samples for autotrophic and
heterotrophic nanoflagellates and ciliates were taken at 10 selected stations and 5 to 7
depths per profile (see excel file).
Planning for data availability:
In situ data
The bacterial production, autotrophic and heterotrophic nano flagellates data along
profiles are available in the excel file (October 2005). Ectoenzymatic activities
(concentration kinetics) will be available at the end of 2006. The ciliate abundance,
biomass and grazing data will be available in spring 2006.
Data file description: the following excel files includes 2 sheets. One for explanation and
one for data. In the following table are the different columns and units (see also
the explanation sheet of the excel file)
Station
ctd
Btle
P[dbar]
BP
BP[sd]
HN[nb]
PN[nb]
HN[C]
PN[C]
type of station
CTD number
bottle number
depth associated to the bottle number (from ctd -rosette files)
bacterial production in ngCper liter per hour
error associated to the measurement of BP (ng C per liter per
hour)
abundance of heterotrophic nanoflagellates (cells per ml)
abundance of autotrophic nanoflagellates (cells per ml)
biomass of heterotrophic nanoflagellates (µg C per liter)
biomas of autotrophic nanoflagellates (µg C per liter)
These data are not yet validated (October 2005)
Enrichment experiments
Some data are already available (bacterial production, HNAN and PNAN abundances and
biomasses, ectoenzymatic activities). They are included in the global data file of OBEX
experiments (Julie Mosseri = person responsible)
These data are not yet validated (October 2005)
Methodological references:
Karayanni H, Christaki U, Van Wambeke F, Denis M, Moutin T. 2005. Influence of
ciliated protozoa and heterotrophic nanoflagellates on the fate of primary production in
NE Atlantic Ocean. Journal of Geophysical Research, vol 110, C07S15,
doi:10.1029/2004JC002602
Karayanni H, Christaki U, Van Wambeke F, Dalby A, 2004. Evaluation of double
formalin-Lugol’s fixation in assessing number and biomasses of ciliates: an example of
estimations at mesoscale in NE Atlantic. Journal of Microbiological Methods, 56:349358.
Van Wambeke F, Christaki U, Giannakourou A, Moutin T & Souvemerzoglou K. 2002.
Longitudinal and vertical trends of bacterial limitation by phosphorus and carbon in the
Mediterranean Sea. Microbial Ecology, 43:119-133.