Aims Understanding the relative importance of historical and environ-mental processes in the structure and composition of communities is one of the longest quests in ecological research.Increasingly,researchers are re...Aims Understanding the relative importance of historical and environ-mental processes in the structure and composition of communities is one of the longest quests in ecological research.Increasingly,researchers are relying on the functional and phylogeneticβ-diversity of natural communities to provide concise explanations on the mechanistic basis of community assembly and the drivers of trait variation among species.The present study investigated how plant functional and phylogeneticβ-diversity change along key environmental and spatial gradients in the Western Swiss Alps.Methods Using the quadratic diversity measure based on six functional traits-specific leaf area,leaf dry matter content,plant height,leaf carbon content,leaf nitrogen content and leaf carbon to nitrogen content alongside a species-resolved phylogenetic tree-we relate variations in climate,spatial geographic,land use and soil gradients to plant functional and phylogenetic turnover in mountain commu-nities of the Western Swiss Alps.Important Findings Our study highlights two main points.First,climate and land-use factors play an important role in mountain plant community turnover.Second,the overlap between plant functional and phy-logenetic turnover along these gradients correlates with the low phylogenetic signal in traits,suggesting that in mountain land-scapes,trait lability is likely an important factor in driving plant community assembly.Overall,we demonstrate the importance of climate and land-use factors in plant functional and phyloge-netic community turnover and provide valuable complementary insights into understanding patterns ofβ-diversity along several ecological gradients.展开更多
Aims Food-deceptive pollination,in which plants do not offer any food reward to their pollinators,is common within the Orchidaceae.As food-deceptive orchids are poorer competitors for pollinator visitation than reward...Aims Food-deceptive pollination,in which plants do not offer any food reward to their pollinators,is common within the Orchidaceae.As food-deceptive orchids are poorer competitors for pollinator visitation than rewarding orchids,their occurrence in a given habitat may be more constrained than that of rewarding orchids.In particular,the success of deceptive orchids strongly relies on several biotic factors such as interactions with co-flowering rewarding species and pollinators,which may vary with altitude and over time.Our study compares generalized food-deceptive(i.e.excluding sexually deceptive)and rewarding orchids to test whether(i)deceptive orchids flower earlier compared to their rewarding counterparts and whether(ii)the relative occurrence of deceptive orchids decreases with increasing altitude.Methods To compare the flowering phenology of rewarding and deceptive orchids,we analysed data compiled from the literature at the species level over the occidental Palaearctic area.Since flowering phenology can be constrained by the latitudinal distribution of the species and by their phylogenetic relationships,we accounted for these factors in our analysis.To compare the altitudinal distribution of rewarding and deceptive orchids,we used field observations made over the entire Swiss territory and over two Swiss mountain ranges.Important Findings We found that deceptive orchid species start flowering earlier than rewarding orchids do,which is in accordance with the hypotheses of exploitation of naive pollinators and/or avoidance of competition with rewarding co-occurring species.Also,the relative frequency of deceptive orchids decreases with altitude,suggesting that deception may be less profitable at high compared to low altitude.展开更多
基金Fellowship grant from the Faculty of Biology and Medicine University of Lausanne,Switzerland.
文摘Aims Understanding the relative importance of historical and environ-mental processes in the structure and composition of communities is one of the longest quests in ecological research.Increasingly,researchers are relying on the functional and phylogeneticβ-diversity of natural communities to provide concise explanations on the mechanistic basis of community assembly and the drivers of trait variation among species.The present study investigated how plant functional and phylogeneticβ-diversity change along key environmental and spatial gradients in the Western Swiss Alps.Methods Using the quadratic diversity measure based on six functional traits-specific leaf area,leaf dry matter content,plant height,leaf carbon content,leaf nitrogen content and leaf carbon to nitrogen content alongside a species-resolved phylogenetic tree-we relate variations in climate,spatial geographic,land use and soil gradients to plant functional and phylogenetic turnover in mountain commu-nities of the Western Swiss Alps.Important Findings Our study highlights two main points.First,climate and land-use factors play an important role in mountain plant community turnover.Second,the overlap between plant functional and phy-logenetic turnover along these gradients correlates with the low phylogenetic signal in traits,suggesting that in mountain land-scapes,trait lability is likely an important factor in driving plant community assembly.Overall,we demonstrate the importance of climate and land-use factors in plant functional and phyloge-netic community turnover and provide valuable complementary insights into understanding patterns ofβ-diversity along several ecological gradients.
基金Centre de Conservation de la Nature du Canton de VaudFederal Office of the EnvironmentSwiss National Science Foundation(3100A0-100754/1 to L.D.B.G.and PBLAA-122727 to I.A.I.).
文摘Aims Food-deceptive pollination,in which plants do not offer any food reward to their pollinators,is common within the Orchidaceae.As food-deceptive orchids are poorer competitors for pollinator visitation than rewarding orchids,their occurrence in a given habitat may be more constrained than that of rewarding orchids.In particular,the success of deceptive orchids strongly relies on several biotic factors such as interactions with co-flowering rewarding species and pollinators,which may vary with altitude and over time.Our study compares generalized food-deceptive(i.e.excluding sexually deceptive)and rewarding orchids to test whether(i)deceptive orchids flower earlier compared to their rewarding counterparts and whether(ii)the relative occurrence of deceptive orchids decreases with increasing altitude.Methods To compare the flowering phenology of rewarding and deceptive orchids,we analysed data compiled from the literature at the species level over the occidental Palaearctic area.Since flowering phenology can be constrained by the latitudinal distribution of the species and by their phylogenetic relationships,we accounted for these factors in our analysis.To compare the altitudinal distribution of rewarding and deceptive orchids,we used field observations made over the entire Swiss territory and over two Swiss mountain ranges.Important Findings We found that deceptive orchid species start flowering earlier than rewarding orchids do,which is in accordance with the hypotheses of exploitation of naive pollinators and/or avoidance of competition with rewarding co-occurring species.Also,the relative frequency of deceptive orchids decreases with altitude,suggesting that deception may be less profitable at high compared to low altitude.
