Impacts of climate change on individual species are increasingly well documented, but we lack understanding of how these effects propagate through ecological communities. Here we combine species distribution models with ecological network analyses to test potential impacts of climate change on >700 plant and animal species in pollination and seed-dispersal networks from central Europe. We discover that animal species that interact with a low diversity of plant species have narrow climatic niches and are most vulnerable to climate change. In contrast, biotic specialization of plants is not related to climatic niche breadth and vulnerability. A simulation model incorporating different scenarios of species coextinction and capacities for partner switches shows that projected plant extinctions under climate change are more likely to trigger animal coextinctions than vice versa. This result demonstrates that impacts of climate change on biodiversity can be amplified via extinction cascades from plants to animals in ecological networks.

-Resource utilisation and foraging ranges of Apidae (excluding Apis and Bombus) were studied in sandy grasslands of the temperate zone by pollen analysis combined with direct observation of bees. Planttaxa composition of 558 pollen loads collected from 56 bee species was determined. We recorded flowervisits using plot-based observations and resource utilisation using pollen analysis. For the most important entomophilous plant species flower-visitation and pollen-analytical data correspond (e.g. Berteroa incana, Centaurea stoebe, Potentilla argentea). Whenever pollen of plant species that are limited in their occurrence could be detected, we were able to use pollen analysis to determine foraging distances, but not maximum foraging distances. Using tree pollen, minimum flight ranges up to 1250 m were documented even for bees with 7 mm body size. Thus pollen analysis not only provides valuable information about foraging on different spatial scales, but also enables foraging ranges to be calculated without experimental manipulation.flight range / foraging range / spatial scales / pollen analysis / floral resources

-We analysed the interaction web of a plant-bee pollinator community (Hymenoptera: Apidae, honeybees excluded) for two years. Based on the ordination of the incidence matrix, both webs showed coherence and clumping but no species turnover. While this may indicate a moderate set of nested subsets and sub-communities, further analysis of nestedness did not reveal uniform results. A null-model analysis of different nestedness metrics showed no evidence despite the asymmetric structure of bipartite graphs. However, further analysis revealed significant modularization within the community with connected hub species within modules and module-interlinking connector species. The web is characterized by 4-6 dominant connector plant species, representing four main flower types. The pattern depends on the year. DCA demonstrates that the connector plant species support resources for bees of different body sizes and behaviour. The pattern is characterized by modularity and the existence of specific connector plant species.coherence / nested subsets / bipartite web / modularity / real network structure

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