Salzer J, Matezki S, Kazda M
Department of Systematic Botany and Ecology, University of Ulm, Albert-Einstein-Allee 11, D - 89073, Ulm, Germany.
Oecologia. 2006 Mar;147(3):417-25. doi: 10.1007/s00442-005-0294-y. Epub 2005 Dec 10.
Climbing plants are known to play an important role in tropical forest systems, but key features for their distribution are only partly understood. Investigation was carried out to find if climbers differ from self-supporting vegetation in their adjustment of leaf parameters over a wide variety of light regimes in different forest types along an altitudinal gradient. Relative photon flux density (PFDrel) was assessed above 75 pairs of strictly linked climbers and supporting vegetation on seven plots between 2,020 and 2,700 m a.s.l. along a mountain range in South-Ecuador up to the Páramo vegetation. Leaf samples from both growth forms were analyzed for leaf area (LA), specific leaf mass (LMA), mass and area-based carbon and nitrogen concentration (C, Carea, N, and Narea) and concentrations of P, K, Ca, Mg, Mn and Al. Leaf size of climbers was independent of general light condition, whereas the leaf size of the self-supporting vegetation increased in shade. LMA increased as expected with altitude and irradiance for both growth forms, but climbers generally built smaller leaves with lower LMA. N, P, and K concentrations were higher in the leaves of climbers than in their supporters. Relationships of LMA and Narea to the light conditions were more pronounced within the climbers than within their supporters. Slope for the regression between climber's Narea and LMA was twice as steep as for the supporter leaves. Al accumulators were only found within the self-supporting vegetation. The investigated traits indicate improved adjustment towards light supply within climbers compared to self-supporting vegetation. Thus climbing plants seem to have a higher potential trade off in resource-use efficiency regarding irradiance and nutrients.
众所周知，攀缘植物在热带森林系统中发挥着重要作用，但其分布的关键特征仍未完全明晰。本研究旨在探究在不同森林类型、沿海拔梯度的多种光照条件下，攀缘植物与自立植被在叶片参数调整方面是否存在差异。在厄瓜多尔南部山脉海拔2020米至2700米之间的七个样地中，对75对紧密相连的攀缘植物及其支撑植被上方的相对光子通量密度（PFDrel）进行了评估，直至帕拉莫植被带。对两种生长形式的叶片样本进行分析，测定叶面积（LA）、比叶质量（LMA）、基于质量和面积的碳氮浓度（C、Carea、N、Narea）以及磷、钾、钙、镁、锰和铝的浓度。攀缘植物的叶片大小与总体光照条件无关，而自立植被的叶片大小在遮荫条件下会增大。两种生长形式的LMA均随海拔和光照强度的增加而增加，但攀缘植物通常叶片较小，LMA较低。攀缘植物叶片中的氮、磷和钾浓度高于其支撑植物。与支撑植物相比，LMA和Narea与光照条件的关系在攀缘植物中更为显著。攀缘植物Narea与LMA之间回归的斜率是支撑植物叶片的两倍。仅在自立植被中发现了铝积累植物。所研究的性状表明，与自立植被相比，攀缘植物对光照供应的适应性更强。因此，在光照和养分的资源利用效率方面，攀缘植物似乎具有更高的潜在权衡能力。
