不同演替阶段中黧蒴栲种群的大小结构与分布格局

在中亚热带常绿阔叶林，有代表性地选择三个黧蒴栲群落类型，即黧蒴栲纯林（常绿阔叶林皆伐地自然演替而成的黧蒴栲纯林，用生长锥对优势木进行随机抽查得其最大年龄为１３ａ）、以黧蒴栲为优势种的混交林（经优势木随机抽测其最大年龄为２４ａ）和黧蒴栲已不成为优势种的混交林（实为天然次生林，优势木随机抽测最大年龄为５３ａ）。测定分析结果表明，黧蒴栲群落在自然演替的前期即幼林阶段的种群大小级结构呈典型的三角状增长型；

SIZE CLASS AND DISTRIBUTION PATTERN OF CASTANOPSIS FISSA POPULATION IN DIFFERENT SUCCESSIONAL STAGES

The spatial distribution and size of Castanopsis fissa population in subtropical evergreen broad-leaved forest were studied in this paper. Pattern of spatial distribution varied in size classes and scales of observation. The age-class structure of population in young pure forest, among which the age of dominant Castanopsis fissa was 13 a, showed triangle-type, suggesting increasingly growing, and their individuals in all age-classes (divided into seedling, short sapling, tall sapling and adult trees) displayed clumped distribution. The age-class structure of population in middle-age mixed forest, in which Castanopsis fissa also dominated the community and the age of dominant Castanopsis fissa tree was 24 a, showed informal dumbbell-type, suggesting the population had come into declining stage, and their individuals in all age-classes (divided into seedling, short sapling, tall sapling and adult trees) also displayed clumped distribution, but its clumped intensity was stronger than the former. The age-class structure of population in old-age mixed forest, among which the age of dominant trees was 53 a, showed breaking inverse triangle, suggesting the population will disappear with the community succession, and their individuals in all age-classes (divided into seedling, short sapling, tall sapling and adult trees) displayed random distribution. Fig 1, Tab 4, Ref 10