Biodiversity: climate change and the ecologist
ABSTRACT The evidence for rapid climate change now seems overwhelming. Global temperatures are predicted to rise by up to 4 °C by 2100, with associated alterations in precipitation patterns. Assessing the consequences for biodiversity, and how they might be mitigated, is a Grand Challenge in ecology.
Full-textDOI: · Available from: Wilfried Thuiller, Feb 28, 2014
- SourceAvailable from: Jason L. Brown
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- "BIOMOD2 accounts for intermodel variability by fitting ensembles of forecasts by simulating across more than one set of initial conditions, model classes, model parameters, and boundary conditions (see Araujo and New 2007 for a review). BIOMOD2 analyzes the resulting range of uncertainties with regard to area bounded by models, predictive consensus, and probabilistic density functions summarizing the likelihood of a species presence estimated from a large ensemble of SDMs (Araujo and New 2007; Thuiller 2007). In lemur species with a number of unique occurrences points >10, model calibration was performed on a random sample of the data (75%), and model evaluation was carried out on the remaining 25% with the true skill statistic (TSS) (10 replicates of each species ). "
ABSTRACT: Geospatial modeling is one of the most powerful tools available to conservation biologists for estimating current species ranges of Earth's biodiversity. Now, with the advantage of predictive climate models, these methods can be deployed for understanding future impacts on threatened biota. Here, we employ predictive modeling under a conservative estimate of future climate change to examine impacts on the future abundance and geographic distributions of Malagasy lemurs. Using distribution data from the primary literature, we employed ensemble species distribution models and geospatial analyses to predict future changes in species distributions. Current species distribution models (SDMs) were created within the BIOMOD2 framework that capitalizes on ten widely used modeling techniques. Future and current SDMs were then subtracted from each other, and areas of contraction, expansion, and stability were calculated. Model overprediction is a common issue associated Malagasy taxa. Accordingly, we introduce novel methods for incorporating biological data on dispersal potential to better inform the selection of pseudo-absence points. This study predicts that 60% of the 57 species examined will experience a considerable range of reductions in the next seventy years entirely due to future climate change. Of these species, range sizes are predicted to decrease by an average of 59.6%. Nine lemur species (16%) are predicted to expand their ranges, and 13 species (22.8%) distribution sizes were predicted to be stable through time. Species ranges will experience severe shifts, typically contractions, and for the majority of lemur species, geographic distributions will be considerably altered. We identify three areas in dire need of protection, concluding that strategically managed forest corridors must be a key component of lemur and other biodiversity conservation strategies. This recommendation is all the more urgent given that the results presented here do not take into account patterns of ongoing habitat destruction relating to human activities.Ecology and Evolution 02/2015; 5(6). DOI:10.1002/ece3.1418 · 1.66 Impact Factor
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- "The conservation of biodiversity is one of the most important tasks of modern ecology. Although plant species are subjected to extinction by natural, evolutionary forces, it has been estimated that human influence may have accelerated this rate 100-to 1000- fold (Ricketts et al., 2005; Thuiller, 2007). Such an estimate leads to a straightforward conclusion regarding the necessity for the * Corresponding author. "
ABSTRACT: Aim of the present study was to evaluate the genetic diversity of selected European populations of Marsilea quadrifolia L and to assess the applicability of those genetic resources of Marsilea quadrifolia L that have been preserved in Polish botanical gardens, for the reintroduction of this species into its historical range in Poland. Three Polish populations that originated from botanical collections (Zabrze, Zarow and Pulawy) and four natural populations (two from Slovakia (Slovakia I and Slovakia II), one from France and one from Germany) were analyzed using Amplified Fragment Length Polymorphism (AFLP) markers. A very low level of genetic variation was found both within and between the populations in the study, which likely resulted from a genetic bottleneck probably caused by human activities. Plants with the same AFLP fingerprint were found across several populations; however, singleton samples with a unique AFLP band pattern were also present within all of the populations. The presence of singletons led to relatively high values of Simpson's diversity index, which may suggest a considerable effect of mutations and some possibility of sexual reproduction as sources of the observed variation. The partitioning of molecular variance was calculated using hierarchical AMOVA, which showed that a negligible value of only 0.81% of the variation was explained by the category of population, i.e. plants originating from the botanical collections or from the natural habitats. This result indicates that M. quadrifolia populations from botanical collections resemble natural populations in terms of the level of their genetic variation and that the populations that were obtained from the Polish collections could be used for the successful reintroduction of this species into its historical range in Poland, and a similar situation may be given also in other areas of occurrence of this plant that is under threat throughout its area of occurrence in Europe.Flora - Morphology Distribution Functional Ecology of Plants 11/2014; 209(11). DOI:10.1016/j.flora.2014.08.011 · 1.46 Impact Factor
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- "biodiversity by causing changes in species distributions , species interactions and ecosystem processes (Thomas et al. 2004; Thuiller 2007; Bellard et al. 2012). Global warming is one of the salient features of global environmental change. "
ABSTRACT: Climate change and plant invasion are two of the most important ecological issues facing the world today. Extreme events are likely to play an important role in plant invasion. For example, tolerance to temperature stress is critical for plant germination and survival of seedlings. Nonnative invasive species tend to differ from co-occurring native species in several traits. Increased mean temperatures are known to enhance the risk of plant invasions, but few experimental studies have linked plant invasion to both increasing mean temperature and extreme (low and high) temperatures. Ten plant species from Asteraceae (six nonnative invasive and four native species) were chosen and six temperatures (extremely low, average winter, average annual, average summer, high and extremely high) were used to test the effects of extreme temperatures on plant invasion in southern China. The results showed that nonnative invasive plant species (IS) germinated more readily and the seedlings grew better than those of native plant species (NS) at high temperatures, suggesting that global warming may facilitate invasion. Extreme temperatures decreased the seed germination rate and seedling growth of both IS and NS, although NS were more tolerant of extremely low temperatures (5/0 °C). IS, in turn, were more tolerant of extremely high temperatures (40/35 °C). Extreme high temperatures may increase the risk of plant invasion because IS seedlings are better able to become established, whereas low temperatures may hinder invasion. In addition, the species-specific differences in plant origin (IS and NS) and temperature tolerance were correlated with other climatic factors and should be considered in managing invasive species in a changing world.Biological Invasions 10/2014; 16(10):2049-2061. DOI:10.1007/s10530-014-0647-8 · 2.72 Impact Factor