Sterck F J, Poorter L, Schieving F
Forest Ecology and Forest Management Group, Wageningen University, P.O. Box 47, 6700 AA Wageningen, The Netherlands.
Am Nat. 2006 May;167(5):758-65. doi: 10.1086/503056. Epub 2006 Mar 20.
A dominant hypothesis explaining tree species coexistence in tropical forest is that trade-offs in characters allow species to adapt to different light environments, but tests for this hypothesis are scarce. This study is the first that uses a theoretical plant growth model to link leaf trade-offs to whole-plant performances and to differential performances across species in different light environments. Using data of 50 sympatric tree species from a Bolivian rain forest, we observed that specific leaf area and photosynthetic capacity codetermined interspecific height growth variation in a forest gap; that leaf survival rate determined the variation in plant survival rate under a closed canopy; that predicted height growth and plant survival rate matched field observations; and that fast-growing species had low survival rates for both field and predicted values. These results show how leaf trade-offs influence differential tree performance and tree species' coexistence in a heterogeneous light environment.
一个解释热带森林中树种共存的主流假说是,性状之间的权衡使物种能够适应不同的光照环境,但对这一假说的检验却很少。本研究首次使用理论植物生长模型,将叶片权衡与整株植物的表现以及不同光照环境下物种间的差异表现联系起来。利用来自玻利维亚雨林的50种同域树种的数据,我们观察到,比叶面积和光合能力共同决定了林窗内种间高度生长的差异;叶片存活率决定了郁闭树冠下植物存活率的差异;预测的高度生长和植物存活率与实地观察结果相符;快速生长的物种在实地和预测值中的存活率都很低。这些结果表明了叶片权衡如何影响树木在异质光照环境中的差异表现和树种共存。