Horizontal, but not vertical canopy structure is related to stand functional diversity in a subtropical slope forest
Horizontal, but not vertical canopy structure is related to stand functional diversity in a subtropical slope forest
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DOI：
10.1007/s11284-011-0887-3
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发表时间：
2011
影响因子：
2
通讯作者：
Anne Lang;W. Härdtle;H. Bruelheide;W. Kröber;M. Schröter;H. Wehrden;G. Oheimb
中科院分区：
文献类型：
--
作者：
Anne Lang;W. Härdtle;H. Bruelheide;W. Kröber;M. Schröter;H. Wehrden;G. Oheimb
本研究的目的是分析高度多样化的亚热带阔叶林的水平和垂直冠层结构与树木功能多样性的关系，在不同演替阶段进行分层。这是特别有趣的，因为许多关键的生态系统过程和功能与森林冠层的安排有关。我们评估了林分相关功能多样性（FDQ，测量为叶片性状的Rao二次熵）以及其他环境变量对林分水平[测量为相对树冠投影面积（CPAr）]和垂直[相对树冠重叠，树冠定位变量的变异系数（CV）]结构的影响。混合效应模型分析显示fdq和CPAr呈负相关（p= 0.025；估计为- 0.07）。fdqn对林冠垂直结构无显著影响（p < 0.05）。讨论了林冠和亚林冠物种的资源分配和生态位分化。演替阶段正影响冠长CV (p= 0.019，估计值0.03)，但对其他响应变量无影响。坡度对冠长CV的影响显著（p= 0.004，估计为- 0.05），坡向对平均冠高CV的影响显著（p= 0.036，估计为- 0.03）。垂直树冠定位的复杂性取决于研究区非均质坡度地形，这可能模糊了fdq与垂直树冠结构的关系。
The aim of this study was to analyse the relation of horizontal and vertical canopy structure to tree functional diversity of a highly diverse subtropical broad-leaved slope forest, stratified for different successional stages. This is of particular interest because many key ecosystem processes and functions are related to the arrangement of forest canopies. We assessed the effect of stand-related functional diversity (FDQ, measured as Rao’s quadratic entropy of leaf traits), together with other environmental variables on horizontal [measured as relative crown projection areas (CPAr)] and vertical [relative crown overlap, coefficients of variation (CV) of crown positioning variables] structure of the upper canopy at the local neighbourhood level. The analyses with mixed effects models revealed a negative relation (p= 0.025; estimate −0.07) between FDQand CPAr. No significant effect of FDQon vertical canopy structure has been found (p> 0.05). The findings are discussed with regard to resource partitioning and niche differentiation of canopy and sub-canopy species. Successional stage positively impacted the CV of crown length (p= 0.019; estimate 0.03) but did not affect other response variables. The sloping terrain strongly influenced vertical canopy structure as revealed by the significant effect of slope inclination on CV of crown length (p= 0.004; estimate −0.05) and of slope aspect on CV of mean crown height (p= 0.036; estimate −0.03). The high complexity of vertical crown positioning depending on the heterogeneous sloping terrain of the study area may have obscured relations of FDQto vertical canopy structure.