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了解优势树种叶片多水平的功能性状沿海拔梯度的变化及其内在关联,有助于预测优势种应对气候变化的响应与适应.本文研究了青冈属树种叶片气孔、解剖和形态性状沿海拔梯度的变化及其与环境调控因子的关联,探究了其生态策略是否随海拔发生改变.在海南尖峰岭热带森林,沿海拔梯度(400-1400 m)采集了6种常绿青冈:竹叶青冈(Cyclobalanopsis bambusaefolia)、雷公青冈(C.hui)、托盘青冈(C.patelliformis)、饭甄青冈(C.fleuryi)、吊罗山青冈(C.tiaoloshanica)和亮叶青冈(C.phanera)叶片,用于气孔、解剖和形态性状的测定.研究结果表明,随海拔升高,青冈树种叶片气孔密度、气孔孔隙度指数和叶面积显著增加,但海绵组织厚度比和干物质含量则显着降低.叶片气孔、解剖和形态性状沿海拔梯度的变化主要受年均温、年降水量和土壤pH值调控.在低海拔和高海拔处,青冈属采取“耐受”和“竞争”策略,而在中海拔处,则是“竞争”策略.土壤磷含量和土壤pH值随海拔的变化可能是驱动其生态策略转变的主要原因.该结果揭示,热带森林优势树种青冈可通过从气孔细胞-组织解剖结构-叶片水平功能性状的改变来响应环境变化.“,”Aims Understanding variation and coordination of leaf traits at multiscales along elevational gradients can help predict the likely responses of dominant species to climate change.We seek to determine the extent to which variation in leaf stomatal,anatomical and morphological traits is associated with environmental factors,and whether ecological strategies of Cyclobalanopsis species shift with elevations.Methods In a tropical forest landscape in iianfengling,South China,we determined leaf traits related to stomata,anatomy and morphology of six evergreen oak species (Cyclobalanopsis bambusaefolia,C.hui,C.patelliformis,C.fleuryi,C.tiaoloshanica and C.phanera) along a long elevational gradient (400-1400 m above sea level).Important Findings We found that stomatal density and stomatal pore index increased,whereas spongy mesophyll thickness to leaf thickness ratios decreased,significantly with elevation.The leaf area and leaf dry matter content increased and decreased,respectively,with elevation.Variations in stomatal,anatomical and morphological traits were mainly correlated to the mean annual temperature,mean annual sum precipitation and soil pH.At low and high elevations,the oak species exhibited strong stress tolerance combined with competition strategy,while they shifted toward more clearly the competitive strategy at intermediate elevations.And the changes in soil phosphorus concentration and soil pH along the elevation may drive the shift of ecological strategy.The results showed that the dominant oak species in tropical forests respond to environmental change by modulating traits at multiple levels,from that of the individual cell,through tissue and up to the whole leaf scale.