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【目的】了解不同演替阶段的森林种群结构及更新状态可以为促进森林群落演替提供理论参考。【方法】基于3块样地数据,分析不同演替阶段的杨桦次生林、云冷杉针阔混交林和云冷杉近原始林内主要乔木树种及幼树的种群结构,并用O-ring单变量统计分析幼树空间分布格局。【结果】随着演替进行,群落内乔木株数逐渐减少,而胸高断面积相反。先锋树种白桦、杨树等逐渐退出群落。3个群落主林层乔木径阶分布均呈倒“J”形,次生林以小径级林木为主,另外两个群落以中、大径级林木居多。3个群落幼树种类单一,白桦、杨树等先锋树种鲜有幼树出现;云冷杉针阔混交林幼树数量充足,且幼树随地径级呈负指数分布;次生林内幼树最少,但地径、苗高明显优于其他两个群落。次生林群落幼树以随机分布为主,云冷杉林和近原始林中冷杉、云杉及色木幼树在小尺度呈明显的聚集分布,随尺度增大多呈均匀或随机分布。【结论】杨桦次生林和云冷杉针阔混交林处于正向演替进程中,而近原始林树种结构不合理,更新较差,应采取择伐等经营措施调整其结构,促进林分发展。
【Objective】 Understanding the forest population structure and renewal status in different succession stages can provide theoretical reference for promoting forest community succession. 【Method】 Based on the data of three plots, the population structure of main tree species and young saplings in secondary succession stages of Populus davidiana, Spruce-fir-broadleaved forest and near virgin forest was analyzed and analyzed by O-ring univariable statistical analysis Sapling spatial distribution pattern. 【Result】 With the succession of succession, the number of trees in the community gradually decreased while the area of chest height decreased. Pioneer tree birch, poplar and other gradual withdrawal from the community. The tree stand diameter distribution of the three main forest stands was inverted “J”, the secondary forest was dominated by small-diameter forest, and the other two communities were mostly middle and large-diameter forest. There was a single species of young tree in three communities, and few young trees appeared in pioneer tree species such as white birch and poplar. The number of spruce fir-fir mixed broad-leaved forest was sufficient and the young tree distributed negative exponential distribution with the mean diameter. , Seedling height obviously better than the other two communities. The young trees in the secondary forest communities were mainly distributed randomly. The fir, spruce and Sequoia saplings in the spruce-fir and near-virgin forests were obviously aggregated on a small scale and distributed uniformly or randomly with increasing scale. 【Conclusion】 Poplar secondary forest and spruce-fir and broad-leaved mixed forest are in the process of forward succession. However, the structure of near-primary forest is unreasonable and the update is poor. Management measures such as selective cutting should be adopted to adjust its structure and promote the development of stand.