Our analyses show significant differences between predictions from different models, with predicted changes in range size by 2030 differing in both magnitude and direction (e.g. from 92 loss to 322 gain). We explain differences with reference to two characteristics of the modelling techniques: data input requirements (presence/absence vs. presence-only approaches) and assumptions made by each algorithm when extrapolating beyond the range of data used to build the model. The effects of these factors should be carefully considered when using this modelling approach to predict species ranges. Main conclusions We highlight an important source of uncertainty in assessments of the impacts of climate change on biodiversity and emphasize that model predictions should be interpreted in policy-guiding applications along with a full appreciation of uncertainty.Resource Type: Journal Papers
The effects of Pleistocene glaciations on the genetic characteristics of the most austral conifer in the world, Pilgerodendron uviferum, were analysed with specific reference to the hypothesis that the species persisted locally in ice-free areas in temperate South America.
Results indicated that Pilgerodendron populations are highly monomorphic, probably reflecting past population bottlenecks and reduced gene flow. Southernmost populations tend to be the least genetically variable and were therefore probably more affected by glacial activity than northern ones. Populations located outside ice limits seem to have been isolated during the glacial period. The presence of centres of genetic diversity, together with the lack of a significant correlation between genetic and geographical distances and the absence of geographical patterns of allelic frequencies at most analysed alleles, may indicate that Pilgerodendron did not advance southward after the last glaciation from a unique northern refugium, but spread from several surviving populations in ice-free areas in Patagonia instead.Resource Type: Journal Papers
A new, systematic review of the evidence on the effectiveness of ecosystem-based approaches to adaptation (EbA) has been carried out to review the effectiveness of EbA and highlight the knowledge gaps. This research was undertaken as a collaboration between BirdLife International, UNEP-WCMC, IIED and the University of Cambridge.
Ecosystem-based approaches to adaptation (EbA) integrate the use of biodiversity and ecosystem services into an overall strategy for helping people adapt to climate change. To date, however, insight into these approaches has often been based on anecdotal case studies of local people’s use of ecosystems. Although they are informative, they can provide rather limited insight in terms of measuring and evaluating the effectiveness of EbA, especially compared with technical or structural adaptation measures. A new, systematic review of EbA evidence has been carried out to interrogate the scientific literature and review studies from around the world, from many different ecosystems and adopting a wide range of adaptation approaches utilising ecosystems. We conclude that EbA approaches are effective and deserve greater policy attention and political support to reach their full potential.Resource Type: Reports
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