物种多维生态位宽度测度

MULTIVARIATE MEASURE OF NICHE BREADTH

经典的生态位宽度测度式基于物种在单一生态位维上各资源状态的分布比例量，而难以应用于物种在多维生态位空间的宽度测度。本文在ｎ维生态位空间分割为分室的基础上，定义物种生态位宽度为物种在分室上分布与样本在分室的频率分布之间的吻合度。根据最小判别信息统计量，推导出一可基于物种分布比例量也可基于实测值的生态位宽度测度式，并以华南鼎湖山自然保护区的厚壳桂（Ｃｒｙｐｔｏ－ｃａｒｙａ）群落中物种与土壤因子数据为例加以说明，结果表明优势树种具较宽生态位。

mpirical niche breadth measures were formulated based on the proportional speciesperformance over the resource states along a single niche dimension. In this paper,nichebreadth is defined as the fitness between species performance,either proportional or not,andthe distribution of sampling unit frequencies over the compartments of the n-dimensinal nichespace.An index is derived to measure this based on minimum discrimination informationstatistic. An example is presented using survey data of species and soil variables from theCryptocarya community of Dinghushan Nature Reserve in South China.The results indicate that dominant species have broader niches than subordinate species.