基于功能性状的锐齿槲栎林共存树种生态策略差异

Differential ecological strategies in functional traits among coexisting tree species in a Quercus alienavar.acuteserrata forest

局域群落共存树种功能性状的比较是分析不同树种生态策略差异的有效手段,对于理解森林群落物种共存机制及指导森林植被恢复至关重要。该研究以秦岭中低山地带性植被锐齿槲栎(Quercus aliena var.acuteserrata)林为研究对象,分析了群落内5个共存树种叶、茎和细根功能性状及其组合的差异。结果表明:不同树种在地上和地下功能性状上存在明显的差异,尤其在叶片资源获取和防御策略上存在明显的分异。其中,青榨槭(Acerdavidii)偏向于快速资源获取一端,而千金榆(Carpinuscordata)偏向于慢速资源获取一端;三桠乌药(Linderaobtusiloba)偏向于高抵抗和防御能力一端,而四照花(Cornus kousa subsp.chinensis)偏向于低抵抗和防御能力一端;优势种锐齿槲栎在2种策略梯度上都表现为中间型策略。锐齿槲栎林共存树种功能性状及其组合上的差异反映了其生态策略和生态位的不同,这可能是驱动其稳定共存的重要机制。

Aims Comparing functional traits of coexisting tree species in natural forests can reveal the adaptation strategies of different tree species to different habitats,which is essential for understanding the coexistence mechanism of the local forest community and guiding forest restoration.Methods In this study,we compared the functional traits of five coexisting tree species in a Quercus aliena var.acuteserrata forest,the zonal vegetation in the Qinling Mountains,and further examined the difference in the traits space defined by the first two principal component analysis(PCA)axes to reveal the differences of these tree species in ecological strategies.Important findings The results showed that there were obvious differences in the above-and belowground functional traits of different tree species,especially in the strategies of leaf resource acquisition and defense.Specifically,Acer davidi tended to have more acquisitive leaf traits and fine root traits,while Carpinus cordata was relatively more conservative in leaf and fine root traits.Lindera obtusiloba was inclined to have leaves with high resistance and defense ability,while leaves of Cornus kousa subsp.chinensis showed low resistance and defense ability.The dominant species,Q.aliena var.acuteserrata,occupied the middle position along the strategy gradient.The differences in the functional traits and their combinations of coexisting tree species in Q.aliena var.acuteserrata forest reflect their differences in ecological strategies and niches,which may contribute to their stable coexistence.