Wang Hua-Feng, Xu Meng
Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresources Institute of Tropical Agriculture and Forestry Hainan University Haikou China.
Department of Mathematics Pace University New York NY USA.
Ecol Evol. 2017 Nov 9;7(24):10815-10828. doi: 10.1002/ece3.3594. eCollection 2017 Dec.
Research on individual trait variation has gained much attention because of its implication for ecosystem functions and community ecology. The effect of individual variation on population and community abundance (number of individuals) variation remains scarcely tested. Using two established ecological scaling laws (Taylor's law and abundance-size relationship), we derived a new scaling relationship between the individual size variation and spatial variation of abundance. Tested against multi-plot tree data from Diaoluo Mountain tropical forest in Hainan, China, the new scaling relationship showed that individual size variation reduced the spatial variation of community assemblage abundance, but not of taxon-specific population abundance. The different responses of community and population to individual variation were reflected by the validity of the abundance-size relationship. We tested and confirmed this scaling framework using two measures of individual tree size: aboveground biomass and diameter at breast height. Using delta method and height-diameter allometry, we derived the analytic relation of scaling exponents estimated under different individual size measures. In addition, we used multiple regression models to analyze the effect of taxon richness on the relationship between individual size variation and spatial variation of population or community abundance, for taxon-specific and taxon-mixed data, respectively. This work offers empirical evidence and a scaling framework for the negative effect of individual trait variation on spatial variation of plant community. It has implications for forest ecosystem and management where the role of individual variation in regulating population or community spatial variation is important but understudied.
由于个体性状变异对生态系统功能和群落生态学具有重要意义，因此对其的研究备受关注。个体变异对种群和群落丰度（个体数量）变异的影响仍鲜有检验。利用两个已确立的生态尺度定律（泰勒定律和丰度-大小关系），我们推导出了个体大小变异与丰度空间变异之间的新尺度关系。通过对中国海南吊罗山热带森林的多地块树木数据进行检验，新尺度关系表明个体大小变异降低了群落组合丰度的空间变异，但并未降低特定分类群种群丰度的空间变异。群落和种群对个体变异的不同响应通过丰度-大小关系的有效性得以体现。我们使用两种个体树木大小的度量方法：地上生物量和胸径，对这个尺度框架进行了检验和确认。利用德尔塔方法和树高-直径异速生长关系，我们推导出了在不同个体大小度量下估计的尺度指数的解析关系。此外，我们分别使用多元回归模型，针对特定分类群数据和混合分类群数据，分析了分类群丰富度对个体大小变异与种群或群落丰度空间变异之间关系的影响。这项工作为个体性状变异对植物群落空间变异的负面影响提供了实证证据和一个尺度框架。它对森林生态系统和管理具有重要意义，在森林生态系统和管理中，个体变异在调节种群或群落空间变异方面的作用虽很重要，但却未得到充分研究。
