Threat or invasive status in legumes is related to opposite extremes of the same
ecological and life-history attributes.
Bradshaw, Corey J. A.1,2,3 corey.bradshaw@adelaide.edu.au
Giam, Xingli4
Tan, Hugh T. W.4
Brook, Barry W.1
Sodhi, Navjot S.4
Journal of Ecology; Sep2008, Vol. 96 Issue 5, p869-883, 15p, 5 charts, 5 graphs
1. The urgency and scale of the global biodiversity crisis requires the application of
generalized predictors of a species’ likelihood of going extinct or becoming
invasive in non-native areas. A common approach is to correlate species’
ecological and life-history characteristics (attributes, traits) with the probability of
becoming either threatened (responding negatively to human activity), or invasive
(responding positively). The limitation of previous studies is that the fates of
becoming threatened or invasive have generally been treated in isolation. 2. Here
we consider the problem of threat and invasiveness in unison based on analysis of
one of the largest-ever species attributes data bases (8906 species) compiled for a
single plant family (Fabaceae). We used generalized linear mixed-effects models
(using taxonomic grouping to control for within-family phylogenetic
relationships) to correlate species’ life-history and ecological traits to three
response variables: probability of being (i) threatened or not, (ii) invasive or not,
and (iii) threatened or invasive. 3. We found that tall, annual, range-restricted
species with tree-like growth forms, inhabiting closed-forest and lowland sites are
more likely to be threatened. Conversely, climbing and herbaceous species that
naturally span multiple floristic kingdoms and habitat types are more likely to
become invasive. 4. Synthesis. These results support the idea that at least for one
of the richest plant families, species’ life-history and ecological traits correlate
with a fate response to anthropogenic global change. Our results show that species
do demonstrate particular susceptibility to either fate based on their evolved traits,
and that traits generally correlated with invasiveness are also those that correlate
with a reduced probability of becoming threatened. [ABSTRACT FROM
AUTHOR]
1
Research Institute for Climate Change and Sustainability, School of Earth and
Environmental Sciences, University of Adelaide, South Australia 5005, Australia
2
South Australian Research and Development Institute, P.O. Box 120, Henley
Beach, South Australia 5022, Australia
3
School for Environmental Research, Institute of Advanced Studies, Charles
Darwin University, Darwin 0909, Northern Territory, Australia
4
Department of Biological Sciences, National University of Singapore, 14 Science
Drive 4, Singapore 117543, Republic of Singapore
ISSN:
00220477
DOI:
10.1111/j.1365-2745.2008.01408.x
Accession Number:
33654529
Database:
Academic Search Premier
Taming the wild and ‘wilding’ the tame: Tree breeding and dispersal in Australia
and the Mediterranean.
Breton, Catherine1
Guerin, Jenny2
Ducatillion, Catherine3
Médail, Frédéric4
Kull, Christian A.5
Bervillé, André6 andre.berville@supagro.inra.fr
Plant Science; Sep2008, Vol. 175 Issue 3, p197-205, 9p
Abstract: The olive (Olea europaea) and the wattles (mimosas or Acacia spp.) are typical
tree species of the Mediterranean and Australia, respectively. Both trees have been
subject to trans-oceanic movements, including the introduction of Mediterranean olives
to Australia, and the introduction of Australian wattles to the Mediterranean. In each
case, the trees have naturalised and become problematic invasives. Based on case studies
of such movements, we compare and contrast the processes of transfer, dispersal, and
genetic changes of these trees, with particular attention to crop–feral–wild complexes in
both their home ranges and in introduced areas. Contrasting ecological, social, and
economic landscapes shape the possibilities for crop–feral–wild interactions and for
invasiveness. [Copyright 2008 Elsevier]
1
Institut de Botanique, Université Montpellier 2, Centre de Bio-Archéologie et
d’écologie, UMR-5059, CNRS/EPHE/univ-Montpellier, Institut de Botanique,
163 Avenue A Broussonnet, 34165 Montpellier cedex, France
2
University of Adelaide School of Agriculture and Wine, PMB1, Glen Osmond,
SA 5064, Australia
3
INRA, jardin botanique Villa Thuret, 90 chemin Raymond, 06160 Antibes/Juanles-Pins, France
4
Institut Méditerranéen d’Écologie et de Paléoécologie (IMEP, CNRS UMR
6116), Université Paul Cézanne (Aix-Marseille III), Europole méditerranéen de
l’Arbois, Bâtiment Villemin, BP 80, F - 13545 Aix-en-Provence cedex 04, France
5
School of Geography and Environmental Science, Monash University,
Melbourne, VIC 3800, Australia
6
INRA UMR DIA-PC, 2 place Viala, 34060 Montpellier cedex 1, France
ISSN:
01689452
DOI:
10.1016/j.plantsci.2008.05.013
Accession Number:
33386398
Database:
Academic Search Premier
Modelling the consequences of crop–wild relative gene flow: a sensitivity
analysis of the effects of outcrossing rates and hybrid vigour breakdown in
Lactuca.
Authors:
Hooftman, Danny A. P.1 d.a.p.hooftman@uva.nl
Oostermeijer, J. Gerard B.1
Marquard, Elisabeth1
den Nijs, Hans (J.) C.M.1
Source:
Journal of Applied Ecology; Aug2008, Vol. 45 Issue 4, p1094-1103, 10p
Abstract:
1. Hybridization between crops and their wild relatives may enhance invasiveness
and change their niche dynamics. This is regarded as a major biosafety problem in
terms of the development of noxious, invasive weeds and the loss of the genetic
identity of native species. Modelling the consequences of hybridization is
becoming an important tool for risk assessment. 2. We conducted a sensitivity
analysis of a stochastic hybridization model, predicting changes in genotypic
population composition. The model includes various classes of hybrids between
Lactuca sativa (lettuce) and its wild relative L. serriola, and is based on empirical
demographic measurements of fitness (λ). 3. We calculated the sensitivity of these
transitions and of the following model parameters: outcrossing rate, the temporal
frequency of crop presence, early hybrid fitness, hybrid vigour breakdown rate
and assumed fitness of advanced generation hybrids. 4. In a non-stochastic
simulation, the wild relative was displaced by more vigorous hybrids. The relative
fitness of late generation hybrids in relation to the fitness of the wild taxon had
the strongest effects on the population composition in the long term. 5. The
outcrossing rate affected the estimated population composition strongly but the
proportional impact of this parameter was low compared to the effect of hybrid
fitness. Moreover, the stochastic simulations showed that the level of stochasticity
had only a small effect on the sensitivity of population growth rates to changes in
any of the model parameters, except for changes in the fitness of the wild taxon.
6. Synthesis and applications. It is essential to determine the relative fitness level
of advanced generation hybrids, as this has a much stronger proportional effect
than other factors. Future risk assessment should focus more on long-term fitness
effects and not only on the outcrossing rate and the early establishment of hybrids.
Experiments with multiple generations... [ABSTRACT FROM AUTHOR]
Author Affiliations:
1
Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam,
Kruislaan 318, 1098 SM Amsterdam, The Netherlands
ISSN:
00218901
DOI:
10.1111/j.1365-2664.2008.01508.x
Accession Number:
33017678
Database:
Academic Search Premier
Authors:
Richardson, David M.1 rich@sun.ac.za
Kluge, Robert L.2
Source:
Perspectives in Plant Ecology, Evolution & Systematics; Jul2008, Vol. 10 Issue 3,
p161-177, 17p
Abstract:
Abstract: Despite impressive efforts at clearing stands of invasive Australian
Acacia species in South Africa, insufficient attention has been given to
understanding the role of seed banks in the invasiveness and long-term
persistence of populations. We review information on seeds of these species,
considering seed production, seed rain, and the dynamics of seeds in three layers:
leaf litter, and upper and lower seed banks in the soil. Many factors affect the
accumulation and susceptibility to destruction of seed banks and thus the
opportunities for intervention to reduce seed numbers for each of these
components. Reduction of seed banks is crucial for the overall success of the
multi-million dollar management initiatives against these species. Classical
biological control of buds, flower and young pods has reduced the seed
production of many Australian acacias in South Africa. Fire can be applied to
reduce seed numbers in the leaf litter and upper seed bank in some cases, although
there are serious problems associated with high fire intensities in dense acacia
stands. Other options, e.g. soil inversion and solarisation, exist to exercise limited
reduction of seed numbers in some situations. There is little prospect of
meaningful reduction of seed numbers in the lower seed bank. Preventing the
accumulation of seed banks by limiting seed production through biological
control is by far the most effective means, and in almost all cases the only
practical means, of reducing seed numbers. This must be an integral part of
management strategies. Several invasive Australian acacias are already under
effective biological control, and further work to identify additional potential
agents for all the currently invasive species and potentially invasive alien species
is the top priority for improving the efficiency of management programmes.
[Copyright 2008 Elsevier]
Author Affiliations:
1
Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch
University, Private Bag X1, Matieland 7602, South Africa
2
ARC-Plant Protection Research Institute, Private Bag X6006, Hilton 3245, South
Africa
ISSN:
14338319
DOI:
10.1016/j.ppees.2008.03.001
Accession Number:
32646669
Database:
Academic Search Premier
Invasive plants transform the three-dimensional structure of rain forests.
Authors:
Asner, Gregory P.1 gpa@stanford.edu
Hughes, R. Flint2
Vitousek, Peter M.3
Knapp, David E.1
Kennedy-Bowdoin, Ty1
Boardman, Joseph4
Martin, Roberta E.1
Eastwood, Michael5
Green, Robert O.5
Source:
Proceedings of the National Academy of Sciences of the United States of
America; 3/18/2008, Vol. 105 Issue 11, p4519-4523, 5p, 1 chart, 1 graph, 2 bw
Document Type:
Article
Abstract:
Biological invasions contribute to global environmental change, but the dynamics
and consequences of most invasions are difficult to assess at regional scales. We
deployed an airborne remote sensing system that mapped the location and impacts
of five highly invasive plant species across 221,875 ha of Hawaiian ecosystems.
identifying four distinct ways that these species transform the three-dimensional
(3D) structure of native rain forests. In lowland to montane forests, three invasive
tree species replace native midcanopy and understory plants, whereas one
understory invader excludes native species at the ground level. A fifth invasive
nitrogen-fixing tree, in combination with a midcanopy alien tree, replaces native
plants at all canopy levels in lowland forests. We conclude that this diverse array
of alien plant species, each representing a different growth form or functional
type, is changing the fundamental 3D structure of native Hawaiian rain forests.
Our work also demonstrates how an airborne mapping strategy can identify and
track the spread of certain invasive plant species, determine ecological
consequences of their proliferation, and provide detailed geographic information
to conservation and management efforts. [ABSTRACT FROM AUTHOR]
Author Affiliations:
1
Department of Global Ecology, Carnegie Institution of Washington, Stanford,
CA94305
2
lnstitute of Pacific Islands Forestry, U.S. Forest Service, Hilo, HI 96720
3
Department of Biological Sciences, Stanford University, Stanford, CA 94305
4
Analytical Imaging and Geophysics LLC, Boulder, CO 80303
5
Jet Propulsion Laboratory, Pasadena, CA 91109
ISSN:
00278424
DOI:
10.1073/pnas.0710811105
Accession Number:
31596855
Database:
Academic Search Premier
How do introduction characteristics influence the invasion success of
Mediterranean alien plants?
Authors:
Lambdon, Philip W.1 plambdon@googlemail.com
Lloret, Francisco2 francisco.lloret@uab.es
Hulme, Philip E.3 hulmep@lincoln.ac.nz
Source:
Perspectives in Plant Ecology, Evolution & Systematics; Jul2008, Vol. 10 Issue 3,
p143-159, 17p
Abstract: Invasive plant species are becoming increasingly widespread following
accelerated anthropogenic activity in the Mediterranean region. Humans have
played a central role in the expansion process, and it is important to incorporate
such considerations into management plans. Using generalized linear models, our
first aim was to describe how the invasion success of 862 prominent alien plant
species on Mediterranean islands is related to characteristics of the introduction
process: introduction frequency, date and region of origin, range size and purpose
of import. The importance of each was measured by the numbers of species
present and their average invasiveness. The main findings were: (a) accidental
imports and ornamentals accounted for a high proportion of all aliens, although
neither group had particularly high average invasiveness; (b) introduction
frequency had a comparatively modest influence, with the most commonlyintroduced species naturalized only three times more widely than those rarelyintroduced; (c) rates of species introduction appear to have increased dramatically
in the last century, although aliens which have been present in the region for more
than 200 years were most widespread, indicating that it may be centuries before
some species fill their potential range; (d) there were small tendencies for
successful invaders to originate in the Neotropics or in regions with
Mediterranean climate biomes and to have large range sizes. Our second aim was
to determine whether the number or average invasiveness of species introduced
via a given pathway had the most influence on the overall probability of invasion
on a given island. An elasticity analysis suggested that the number of species was
substantially the best predictor of the two. This finding arises largely because
invasion events are rare and remain unpredictable, and has significant
implications for assessing invasion risk. We discuss how substantial sources of
error and intrinsic ... [Copyright 2008 Elsevier]
Author Affiliations:
1
Global Programmes Department, Royal Society for the Protection of Birds, The
Lodge, Sandy, Bedfordshire SG192DL, UK
2
Unit of Ecology, Department of Animal and Plant Biology, Centre for Ecological
Research and Forestry Applications, Universitat Autònoma de Barcelona, E08193 Bellaterra, Spain
3
National Center for Advanced Bio-Protection Technologies, Lincoln University,
PO Box 84, Canterbury, New Zealand
ISSN:
14338319
DOI:
10.1016/j.ppees.2007.12.004
Accession Number:
32646668
Database:
Academic Search Premier
Seed banks of invasive Australian Acacia species in South Africa: Role in
invasiveness and options for management.
Authors:
Richardson, David M.1 rich@sun.ac.za
Kluge, Robert L.2
Source:
Perspectives in Plant Ecology, Evolution & Systematics; Jul2008, Vol. 10 Issue 3,
p161-177, 17p
Document Type:
Article
Abstract:
Abstract: Despite impressive efforts at clearing stands of invasive Australian
Acacia species in South Africa, insufficient attention has been given to
understanding the role of seed banks in the invasiveness and long-term
persistence of populations. We review information on seeds of these species,
considering seed production, seed rain, and the dynamics of seeds in three layers:
leaf litter, and upper and lower seed banks in the soil. Many factors affect the
accumulation and susceptibility to destruction of seed banks and thus the
opportunities for intervention to reduce seed numbers for each of these
components. Reduction of seed banks is crucial for the overall success of the
multi-million dollar management initiatives against these species. Classical
biological control of buds, flower and young pods has reduced the seed
production of many Australian acacias in South Africa. Fire can be applied to
reduce seed numbers in the leaf litter and upper seed bank in some cases, although
there are serious problems associated with high fire intensities in dense acacia
stands. Other options, e.g. soil inversion and solarisation, exist to exercise limited
reduction of seed numbers in some situations. There is little prospect of
meaningful reduction of seed numbers in the lower seed bank. Preventing the
accumulation of seed banks by limiting seed production through biological
control is by far the most effective means, and in almost all cases the only
practical means, of reducing seed numbers. This must be an integral part of
management strategies. Several invasive Australian acacias are already under
effective biological control, and further work to identify additional potential
agents for all the currently invasive species and potentially invasive alien species
is the top priority for improving the efficiency of management programmes.
[Copyright 2008 Elsevier]
Author Affiliations:
1
Centre for Invasion Biology, Department of Botany and Zoology, Stellenbosch
University, Private Bag X1, Matieland 7602, South Africa
2
ARC-Plant Protection Research Institute, Private Bag X6006, Hilton 3245, South
Africa
ISSN:
14338319
DOI:
10.1016/j.ppees.2008.03.001
Accession Number:
32646669
Database:
Academic Search Premier