天然针阔混交林中马尾松种群的空间分布格局

Spatial Distribution Pattern of Masson Pine Population in Natural Forest Mixed with Conifer and Broad-leaved Tree

用频次分布比较法、聚集度指标法、Ｉｗａｏ的ｘ－ｘ回归式法以及Ｔａｙｌｏｒ幂法则等测定方法研究天然针阔混交林中马尾松种群空间分布格局的结果表明：其分布遵从负二项分布和奈曼－Ａ型分布，且以奈曼－Ａ型分布为佳．分布的基本成分是个体群，以小规模的丛生聚集，丛的大小约为２～３株；根据Ｉｗａｏ的ｘ－ｘ回归式，在可靠性９５％、精确度９０％时，天然针阔混交林中马尾松种群最适抽取样方数在６０～８０之间，并随单位面积马尾松种群平均株数密度的增加而减少．

This paper used frepuency distribution comparative method, clump intensity index, Iwao's X -X regressive analysis method and Taylor exponential equation method to study the spatial distribution pattern of masson pine (Pinus massoniana) population in natural forest mixed with conifer and broad-leaved trees.The results indicated that the spatial distribution pattern of masson pine obeyed negtive binomial distri-bution and Neyman-A distribution, but the later was better. The basic ingredient of distribution was loose colony clumped with small scale of about 2～3 trees. The results of Iwao's X\+ -X regressive analysis showed that the optimum sample numbers for masson pine population in natural forest mixed with conifer and broadleaved trees were between 60 to 80 and it decreased with the increase of average density per unit of masson pine under reliablity 95 per cent and accuracy 90 per cent.