西双版纳热带季节雨林优势树种叶片干旱耐受和机械抗性的协同关系OA

Regional droughts caused by global climate change pose a severe challenge to plant survival.Plant drought resistance and mechanical resistance are key factors determining their growth and survival.Tropical forests,as the terrestrial ecosystems with the highest biodiversity and productivity on Earth,however,the relationship between drought tolerance and mechanical resistance of their dominant tree species leaves remains unclear.This study took the dominant tree species in the tropical seasonal rainforest of Xishuangbanna as the research object.By measuring key morphological and hydraulic traits such as the pressure-volume curve of leaves,leaf mechanical resistance(LMR),leaf dry matter content(LDMC),and leaf mass per area(LMA),and combining phylogenetic analysis to explore evolutionary relationships,the relationship between leaf drought tolerance and mechanical resistance and its driving mechanism were further analyzed.The results showed that the morphological,hydraulic traits and mechanical resistance of leaves of tropical seasonal rainforest tree species varied greatly and were not significantly constrained by phylogeny;leaf drought resistance and mechanical resistance were significantly positively correlated with LMA and LDMC;leaf drought tolerance and mechanical resistance were also significantly positively correlated,and this co-variation relationship was regulated by leaf structural investment.This reveals a synergistic relationship between leaf drought resistance and mechanical resistance in dominant tree species of tropical seasonal rainforests,providing a scientific basis for understanding the ecological adaptation strategies of plants in this region and predicting the dynamics of forest communities under climate change.