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生物多样性沿海拔梯度的分布格局已受到广泛关注.然而,生物多样性格局沿海拔梯度的变异及其潜在机制尚不清楚.整合生物多样性的多维度信息为理解群落构建机制提供了新思路.本研究在我国东部亚热带森林沿海拔270-1470 m的梯度上设置了17个木本植物固定样地,分析了沿海拔梯度植物群落构建的生态和进化驱动力.基于样地内物种出现(0-1数据)和多度信息,计算群落内被子植物的物种和系统发育alpha和beta多样性、系统发育结构等,并量化多样性指标与微气候和地形之间的关系.研究发现,不论多度加权与否,物种alpha多样性均沿海拔升高而增加,物种和系统发育的相似性随海拔距离的增加而呈衰减趋势.然而,多度加权与否会形成不同的系统发育alpha多样性格局.对于系统发育结构而言,沿海拔增加并无明显趋势.地形和微气候是多样性格局和系统发育结构的主要驱动力.与未考虑物种多度的多样性指标相比,多度加权的指标与坡度和胸高断面积相关性更高.这些结果表明,由局域物种多度介导的确定性过程对沿海拔梯度的植物群落构建具有一定影响.“,”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 1 7 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.