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在粤北始兴县罗坝自然保护区以木荷、栲树和马尾松为优势的群落内 ,设置 10 0 0m2 样地 5个 ,应用相邻格子法进行每木调查获得野外资料 .通过对优势种种群结构和空间格局的研究 ,结果表明 ,木荷、栲树种群结构呈金字塔型 ,幼苗贮备达 15 3 8和 9763株·hm-2 ;种群从Ⅰ、Ⅱ级幼苗发育到幼树过程中死亡率较高 ;马尾松种群结构呈倒金字塔型 ,幼苗缺乏 ,幼树只有 4株·hm-2 ,但大树较多 ,达 44株·hm-2 ;在以常绿阔叶树种为主的针阔混交群落中 ,马尾松、栲树种群分布格局为均匀分布 ;在以针叶树为主的针阔混交林群落中 ,两者的空间分布格局为集群分布 ,但两者格局变化原因不同 ;木荷种群空间分布格局在上述群落中均表现为集群分布 ,但聚集强度不同 ,K值为 0 42 80～ 0 975 0 ;木荷种群在不同发育阶段其空间分布格局没有较大差别 ,总体上都是集群分布 .栲树种群在不同发育阶段空间分布格局差别较大 ,除大树是均匀分布外 ,幼树、中树均趋于集群分布 ;马尾松种群分布格局中仅中树为集群分布 ,而幼树与大树均为均匀分布 .不同种群在不同发育阶段空间分布格局的差异与其生物学和生态学特性密切相关 .不同区组对种群空间分布格局产生影响 .
In the community of Luoku Nature Reserve in Shixing County, northern Guangdong, dominated by Schima superba, Castanopsis fargesii and Pinus massoniana, 5 plots of 10 0 m 2 were set up and field data were obtained by using the adjacent grid method. The results showed that the population structure of Schima superba and Castanopsis fargesii were pyramid type, the seedling reserves reached 15 3 8 and 9763 plants · hm-2. The population developed from Ⅰ and Ⅱ seedlings to saplings The mortality of P. massoniana population was inverted pyramid, and the seedlings were scarce. There were only 4 plants · hm-2 in the young tree, but there were more big trees, reaching 44 plants · hm-2. Pinus massoniana and Castanopsis fargesii populations distributed uniformly in coniferous and broad-leaved mixed communities. In coniferous-dominated mixed coniferous and broad-leaved forest, the spatial distribution patterns of the two were clustered, but the reasons for the changes were different. The spatial distribution pattern of Schima superba population showed cluster distribution in all the above communities, but the aggregation intensity was different, K value was 0 42 80 ~ 0 975 0. There was no significant difference in the spatial distribution pattern of Schima superba population at different developmental stages All are cluster distributions The spatial distribution pattern of different developmental stages differed greatly, except that the big tree was evenly distributed, the young tree and middle tree tended to cluster distribution; only the middle tree was the cluster distribution in Pinus massoniana population distribution, while the young tree and the big tree were Uniform distribution.The differences of spatial distribution patterns of different populations at different developmental stages are closely related to their biological and ecological characteristics.The different groups have an impact on the spatial distribution pattern of the populations.