Aims Grazing exerts profound effects on grassland ecosystem service and functions by regulating species composition and diversity,and structuring community assembly worldwide.However,adaptions of phylogenetic diversit...Aims Grazing exerts profound effects on grassland ecosystem service and functions by regulating species composition and diversity,and structuring community assembly worldwide.However,adaptions of phylogenetic diversity and phylogenetic community structure to long-term grazing disturbance remain poorly studied,especially for ecosystems distributed in extreme environments.Methods Here,we conducted an experiment with multigrazing intensities to explore the impacts of grazing disturbance on plant phylogenetic diversity and community structure in an alpine grassland of the Tibetan Plateau.Important Findings Grazing disturbance enriched plant species richness(SR),and stimulated species turnover from regional species pool,consequently changing community species composition.Under low intensities,grazing exerted no obvious effects on phylogenetic diversity and community structure,whereas communities changed from overdispersion to clustering under high grazing intensity.High grazing intensity resulted in stronger environmental filtering,which consequently selected those species with high resilience to grazing disturbance.The observed clustering structure was associated with the colonizing species which were closely related to resident species,and locally extinct species,and distantly related to residents.At the plant functional trait level,high grazing intensity increased species colonization largely by altering the effect of root depth on species colonization compared to light grazing.Our results highlight that solely utilization of SR and diversity cannot fully represent grassland communities responses to grazing.The effects of species turnover on community phylogenetic diversity and structure are entailed to be explored in the future grazing studies.展开更多
Aims Biodiversity patterns along elevational gradients have been well documented.Yet,the variations of biodiversity patterns along elevations and their underlying mechanisms are still unclear.Integrating multiple face...Aims Biodiversity patterns along elevational gradients have been well documented.Yet,the variations of biodiversity patterns along elevations and their underlying mechanisms are still unclear.Integrating multiple facets of biodiversity provides novel insights into the mechanisms for driving community assembly.In this study,species abundance information was incorporated into taxonomic and phylogenetic diversity to reveal the ecological and evolutionary forces of plant community assembly along an elevational gradient in subtropical forests.Methods We selected 17 woody plant plots along an elevational gradient from 270 to 1470 m in eastern China’s subtropical forests.Both presence-based and abundance-based measures of angiosperm species were used to quantify taxonomic alpha diversity,phylogenetic alpha diversity,phylogenetic relatedness,as well as taxonomic and phylogenetic dissimilarity among these plots.And the relations between these measures and climatic and topographic variables were analyzed.Important Findings For both abundance-weighted and unweighted measures,we observed an overall increasing pattern for taxonomic alpha diversity along elevation,and distance-decay trends of taxonomic and phylogenetic similarity with increased elevational distances.However,there were disparity patterns of phylogenetic alpha diversity between abundance-weighted and unweighted measures.For phylogenetic structure,there was no significant trend along elevation.Both topographical and microclimatic variables were main drivers of diversity patterns and phylogenetic structure.Compared with unweighted measures,abundance-weighted measures were strongly related with the slope and stand basal area.Overall,our results prove that deterministic processes mediated by local species abundance imprint on plant community composition along the elevational gradient.展开更多
基金This research was funded by the National Natural Science Foundation of China(31870506)the Strategic Priority Research Program of the Chinese Academy of Sciences(XDB31000000)+1 种基金the Natural Science Foundation of Jiangsu Province(BK20181398)the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD).
基金supported by National Key Research&Development Program of China(2016YFC0501802,2017YFA0604802)National Natural Science Foundation of China(41571195,41725003)the excellent researcher award program from Institute of Geographic Sciences and Natural Resources Research(2016RC102).
文摘Aims Grazing exerts profound effects on grassland ecosystem service and functions by regulating species composition and diversity,and structuring community assembly worldwide.However,adaptions of phylogenetic diversity and phylogenetic community structure to long-term grazing disturbance remain poorly studied,especially for ecosystems distributed in extreme environments.Methods Here,we conducted an experiment with multigrazing intensities to explore the impacts of grazing disturbance on plant phylogenetic diversity and community structure in an alpine grassland of the Tibetan Plateau.Important Findings Grazing disturbance enriched plant species richness(SR),and stimulated species turnover from regional species pool,consequently changing community species composition.Under low intensities,grazing exerted no obvious effects on phylogenetic diversity and community structure,whereas communities changed from overdispersion to clustering under high grazing intensity.High grazing intensity resulted in stronger environmental filtering,which consequently selected those species with high resilience to grazing disturbance.The observed clustering structure was associated with the colonizing species which were closely related to resident species,and locally extinct species,and distantly related to residents.At the plant functional trait level,high grazing intensity increased species colonization largely by altering the effect of root depth on species colonization compared to light grazing.Our results highlight that solely utilization of SR and diversity cannot fully represent grassland communities responses to grazing.The effects of species turnover on community phylogenetic diversity and structure are entailed to be explored in the future grazing studies.
基金This work was supported by the National Natural Science Foundation of China(32071538 to J.Z.and 31600343 to K.S.)Shanghai Natural Science Foundation(20ZR1418100 to J.Z.)East China Normal University to J.Z.and Z.Z.
文摘Aims Biodiversity patterns along elevational gradients have been well documented.Yet,the variations of biodiversity patterns along elevations and their underlying mechanisms are still unclear.Integrating multiple facets of biodiversity provides novel insights into the mechanisms for driving community assembly.In this study,species abundance information was incorporated into taxonomic and phylogenetic diversity to reveal the ecological and evolutionary forces of plant community assembly along an elevational gradient in subtropical forests.Methods We selected 17 woody plant plots along an elevational gradient from 270 to 1470 m in eastern China’s subtropical forests.Both presence-based and abundance-based measures of angiosperm species were used to quantify taxonomic alpha diversity,phylogenetic alpha diversity,phylogenetic relatedness,as well as taxonomic and phylogenetic dissimilarity among these plots.And the relations between these measures and climatic and topographic variables were analyzed.Important Findings For both abundance-weighted and unweighted measures,we observed an overall increasing pattern for taxonomic alpha diversity along elevation,and distance-decay trends of taxonomic and phylogenetic similarity with increased elevational distances.However,there were disparity patterns of phylogenetic alpha diversity between abundance-weighted and unweighted measures.For phylogenetic structure,there was no significant trend along elevation.Both topographical and microclimatic variables were main drivers of diversity patterns and phylogenetic structure.Compared with unweighted measures,abundance-weighted measures were strongly related with the slope and stand basal area.Overall,our results prove that deterministic processes mediated by local species abundance imprint on plant community composition along the elevational gradient.