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351.
Assessing the vulnerability of European butterflies to climate change using multiple criteria 总被引:1,自引:0,他引:1
Risto K. Heikkinen Miska Luoto Niko Leikola Juha Pöyry Josef Settele Otakar Kudrna Mathieu Marmion Stefan Fronzek Wilfried Thuiller 《Biodiversity and Conservation》2010,19(3):695-723
Vulnerability of 100 European butterfly species to climate change was assessed using 13 different criteria and data on species
distributions, climate, land cover and topography from 1,608 grid squares 30′ × 60′ in size, and species characteristics increasing
the susceptibility to climate change. Four bioclimatic model-based criteria were developed for each species by comparing the
present-day distribution and climatic suitability of the occupied grid cells with projected distribution and suitability in
the future using the HadCM3-A2 climate scenario for 2051–2080. The proportions of disadvantageous land cover types (bare areas,
water, snow and ice, artificial surfaces) and cultivated and managed land in the occupied grid squares and their surroundings
were measured to indicate the amount of unfavourable land cover and dispersal barriers for butterflies, and topographical
heterogeneity to indicate the availability of potential climatic refugia. Vulnerability was also assessed based on species
dispersal ability, geographical localization and habitat specialization. Northern European species appeared to be amongst
the most vulnerable European butterflies. However, there is much species-to-species variation, and species appear to be threatened
due to different combinations of critical characteristics. Inclusion of additional criteria, such as life-history species
characteristics, topography and land cover to complement the bioclimatic model-based species vulnerability measures can significantly
deepen the assessments of species susceptibility to climate change. 相似文献
352.
Heidi K. Mod Risto K. Heikkinen Peter C. le Roux Henry Väre Miska Luoto 《Polar Biology》2016,39(4):649-657
Biotic interactions may strongly affect the distribution of individual species and the resulting patterns of species richness. However, the impacts can vary depending on the species or taxa examined, suggesting that the influences of interactions on species distributions and diversity are not always straightforward and can be taxon-contingent. The aim of this study was therefore to examine how the importance of biotic interactions varies within a community. We incorporated three biotic predictors (cover of the dominant vascular species) into two correlative species richness modelling frameworks to predict spatial variation in the number of vascular plants, bryophytes and lichens in arctic–alpine Fennoscandia, in N Europe. In addition, predictions based on single-species distribution models were used to determine the nature of the impact (negative vs. positive outcome) of the three dominant species on individual vascular plant, bryophyte and lichen species. Our results suggest that biotic variables can be as important as abiotic variables, but their relative contributions in explaining the richness of sub-dominant species vary among dominant species, species group and the modelling framework implemented. Similarly, the impacts of biotic interactions on individual species varied among the three species groups and dominant species, with the observed patterns partly reflecting species’ biogeographic range. Our study provides additional support for the importance of biotic interactions in modifying arctic–alpine biodiversity patterns and highlights that the impacts of interactions are not constant across taxa or biotic drivers. The influence of biotic interactions, including the taxon contingency and range-based impacts, should therefore be accounted for when developing biodiversity forecasts. 相似文献
353.
Using data from 46 sites in southern Finland and ordination methods, we examined plant-environment relationships in boreal
mesic semi-natural grasslands at two spatial scales (grain sizes), using plots of 0.25 ha and 1 × 1 m. We applied the variation
partitioning approach to determine the pure fractions of environmental variable groups and their joint effects on plant species
compositional variation in the studied grasslands. The variables related to land-use intensity and high nutrient level (especially
phosphorus) had a major role in explaining the species composition at both scales, although soil heterogeneity and habitat
characteristics also accounted for a notable amount of the species compositional variation at the 0.25 ha grain size. At the
1 × 1 m grain size, the majority of the species compositional variation was related to the “pure” spatial differences between
the studied grasslands (i.e. the site identity (dummy 0/1) variable), whereas the impacts of within-site variation of local
environmental factors were considerably smaller. High nutrient levels and variables related to low land-use intensity, e.g.
litter accumulation, were also significantly correlated with floristic variation at the 1 × 1 m grain size. Rare and declining
grassland species are associated with low-nutrient grassland sites and patches. The main recommendation for the management
planning of boreal semi-natural grasslands is that the first restoration attempts should be targeted to areas where nutrient
levels, particularly that of phosphorus, are relatively low. Soil properties and plant species composition can provide useful
guidelines for defining the correct management procedures for different sites. 相似文献
354.