波密岗乡华山松林优势植物空间格局及其关联性

以藏东南波密岗乡华山松林优势植物华山松、林芝云杉和高山松为研究对象，采用点格局分析方法中的Ripley L函数分析不同等级华山松和优势植物的空间分布格局及其关联性。结果表明:1）华山松的小树(D＜20 cm且H≥100 cm)在整体尺度上(0~50 m)均表现为集群分布，中树(20 cm≤D＜40 cm)在小尺度内(0~16 m)为集群分布，大尺度(17~50 m)呈随机分布，大树(D≥40 cm)在整体尺度内(0~50 m)都呈随机分布。2）华山松在0~50 m尺度内均呈集群分布，随尺度的增长，集聚程度的变化较小；高山松在0~30 m尺度内集群分布，其中在7 m处集聚强度最大，随后集聚强度随尺度的增加而减小，在37~46 m尺度内表现为均匀分布，在30~37 m和46~50 m尺度上为随机分布；林芝云杉在0~49 m尺度上都呈现集群分布，只有在49~50 m处随机分布。3）华山松的种内关联性几乎都表现为不相关，只有小树和中树在9~14 m的尺度上表现为负相关。4）华山松和高山松的种间关联性在0~17 m尺度内表现为空间负相关，在17~50 m的尺度内不相关；华山松和林芝云杉在0~3 m及40~50 m的尺度内不相关，但在3~40 m的尺度上呈负相关；高山松和林芝云杉的关联性变化较大，依次是负相关>不相关>正相关>不相关。

Spatial Pattern and Correlation of Dominant Plants in Pinus armandii Forest in Bomi Gang Township

Taking Pinus armandii,Picea likiangensis var.linzhiensis and Pinus densata,the dominant tree species occurring in Bomi Gang Township,southeast Tibet,as the research objects,the spatial distribution patterns of P.armandii and dominant species with different grades as their correlations were analyzed by using Ripley L function in point pattern analysis method.The results showed that 1) the small trees of P.armandii(D＜20 cm and H≥100 cm) presented cluster distribution on the whole scale (0-50 m),the middle trees (20 cm≤D＜40 cm) presented cluster distribution in small scale (0-16 m) and random distribution in large scale (17-50 m),the big trees (D≥40 cm) were in random distribution in the whole scale (0-50 m).2) P.armandii presented cluster distribution in the scale of 0-50 m,and the degree of aggregation changed little with the increase of scale; P.densata was in cluster distributeion in the scale of 0-30 m,aggregation intensitywas the largest at the scale of 7 m,and then decreased with the increase of scale,which showed random distribution on the scales of 30-37 m and 46-50 m,and uniform distribution at the scale of 37-46 m; P.likiangensis var.linzhiensis showed cluster distribution in the scale of 0-49 m,only random distribution in 49-50 m scale.3) The intraspecific association of P.armandii was almost spatial independent,and only the small (D＜20 cm,H≥100 cm) and middle trees (20 cm≤D＜40 cm) showed negative correlation at the scale of 9-14 m.4) P.armandii and P.densata showed negative correlation at the scale of 0-17 m,and no correlation in the scale of 17-50 m; there was no correlation between P.armandii and P.likiangensis var.linzhiensis in the scales of 0-3 m and 40-50 m,but negative correlation in the scale of 3-40 m; the correlation between P.densata and P.likiangensis var.linzhiensis changed greatly,which showed negative correlation in the scale of 0-28 m,no correlation at the scale of 28-38 m and 49-50 m,and positive correlation in the scale of 38-49 m.