天山云杉林不同发育阶段种群分布格局研究

以新疆西部天山云杉林6hm2永久样地调查数据为基础,采用点格局分析方法,对不同发育阶段的天山云杉种群空间分布格局和种群之间相关性进行统计分析。结果表明:1)调查样地内天山云杉群落物种组成简单,仅7个物种,区系成分均为温带成分,是以天山云杉为主的单优植物群落。2)样地内天山云杉大树个体数较多,小树和中树个体数较少,不同发育阶段其个体密度大小顺序为:大树中树小树,表现为衰退型种群。3)天山云杉不同发育阶段种群分布格局与研究尺度紧密相关,各发育阶段均以聚集型分布为主;不同尺度下均表现为小树的聚集强度最大,中树次之,大树最小。4)天山云杉种群不同发育阶段之间存在着相关性,大树和小树表现为显著的负相关;中树和小树在中小尺度上呈现显著的正相关,大尺度上相关性不显著;中树和大树相关性不显著。

Distribution patterns of Picea schrenkiana var. Tianshanica populations at different developmental stages in the western Tianshan Mountain, northwestern China

Based on data collected from a 6 hm² permanent plot of Picea schrenkiana var. tianshanica in the western Tianshan Mountain, this study examined the spatial distribution of Picea populations and their relevance at different growth stages using an analytical point pattern method. Results show that 1) Picea is the dominant species of single plant communities. Only seven woody species were found within the survey plot and all were species of the temperate elements. 2) Picea populations showed a declining trend, with more old trees and fewer young trees in the plot. 3) Distribution patterns of Picea populations at different developmental stages are closely related to scale, presenting mainly as a cluster distribution. Size of the clusters was greatest for young trees, followed by that of middle-aged trees and old trees. 4) We found correlations between Picea populations at different developmental stages. The correlation between old trees and young trees was significantly negative. The correlation between middle-aged trees and young trees was significantly positive on medium and small scales, but no significant correlation was discovered on a big scale. The correlation between old trees and middle-aged trees was not significant.