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为揭示岭南林场天然混交林的空间结构规律,合理选择种群结构研究方法提供借鉴,本研究在岭南林场混交林内设立面积为1 hm2 的标准地,对标准地内的林木进行每木调查,选取角尺度、混交度和大小比数3 个参数对岭南林场混交林空间结构特征进行分析研究.结果表明:甜槠是优势种,青冈栎和苦槠为亚优势种,与其他8 种乔木共同构成了混交林林生态群落;林分平均角尺度值0.55,林木水平格局为聚集分布;林分平均混交度为0.51,主要以中度混为主;群落中主要树种的平均大小比数排序为鹿角杜鹃＞绵槠=喜树＞青冈栎＞杉木＞毛栗＞甜槠＞木荷＞苦槠＞枫香＞马尾松,其大小比数的均值约为0.49,而林分内各树种的平均直径大小比数处于0.24～0.66 之间,在生产实践上可依据以上结果分树种来确定采伐木,逐步调整岭南林场林分结构使其达到最优水平.“,”In order to investigate the spatial structure rule of natural mixed forests for Lingnan forestry farm and to provide a reference for rational selection of population structure research method,this study set up 1 hm2 sample-plot in Lingnan forestry farm and applied tally to trees in the sample-lot.Then,we used three parameters,including mingling degree,neighborhood comparison and angle index,to study the spatial structure characteristics of mixed forest in Lingnan forestry farm.The results showed that the ecological community of mixed forests was made up of Castanopsise eyrei,Cyclobalanopsis glauca,Castanopsis sclerophylla and other 8 tree species,in which Castanopsise eyrei was the dominant species,and the Cyclobalanopsis glauca and Castanopsis sclerophylla were subdominant species.The average angle index of forest stand was 0.55,and the horizontal pattern of trees was the aggregate distribution.The average mingling degree in the forest stand was 0.51 which was mainly with moderate mixing.According to the average size of neighborhood comparison,main species in the community were ranked as Rhododendron latoucheae＞Lithocarpus henryi=Camptotheca acuminata＞Cyclobalanopsis glauca＞Cunninghamia lanceolata＞Castanea sequinii＞Castanopsis eyrie＞Schima superba＞Castanopsis sclerophylla＞Liquidambar formosana ＞Pinus massoniana.The average of neighborhood co mparison was about 0.49,while the neighborhood comparison of mean diameter of each tree species in forest stand ranged from 0.24～0.66.In the production practice,tree felling could be determined according to the above results,and the stand structure of Lingnan forestry farm could be adjusted gradually to reach the optimum level.