杉木老龄林乔木层主要树种生态位研究

为杉木人工林近自然化改造提供理论依据,文中采用相邻格子法,对长期处于近自然经营条件下的75年生杉木老龄林乔木层主要树种生态位特征进行分析。结果表明:各主要树种重要值与生态位宽度基本上呈正相关。生态位宽度大小顺序为杉木>木荷>丝栗栲>刨花楠>虎皮楠>细齿叶柃>枫香>短梗幌伞枫>毛八角枫>千年桐,除千年桐外,其余树种均有较大生态位宽度。生态位宽度较大的树种间生态位相似性比例较大,生态位重叠也较大。各主要树种生态位宽度与生态位重叠并非正相关关系。杉木在群落中占据主导地位,木荷、丝栗栲、刨花楠与杉木的种间关系比较协调。综合比较各主要树种生态位特征,在近自然经营模式下,木荷、丝栗栲、刨花楠可与杉木良好共存,是较为理想的杉木混交树种。

Niche of main species in the tree layer of old-growth Chinese fir forest

To provide theoretical basis for near-natural plantation transformation of Cunninghamia lanceolata,the method of contiguous gird quadrants was applied to analysis the niche characteristics of main tree species in the tree layer of 75 a old-growth Cunninghamia lanceolata forest which is under long time near-natural restoration.The results indicated that there was a positive correlation between the importance value and the niche breadth of each main tree specie.The niche breadth listed in the order of Cunninghamia lanceolata>Schima superb>Castanopsis fargesii>Machilus pauhio>Daphniphyllum oldhami>Eurya nitida>Liquidambar formosana>Ardis iacrenata>Alangium kurzii>Vernicia montana,each tree specie had a large niche breadth except Vernicia montana.Both niche similarity and niche overlap between tree species increased with niche breadth.There was no positive correlation between niche breadth and niche overlap of main tree species.Cunninghamia lanceolata occupied the dominant position in the community while S.superb,Castanopsis fargesii and M.pauhio shared the environment resources in a good state with it.Comprehensive comparison of the niche characteristics of main tree species,in near-natural forest management, S.superb,Castanopsis fargesii,M.pauhoi can coexist with Cunninghamia lanceolata excellently and they are comparatively ideal tree species for Cunninghamia lanceolata and broad-leaved mixed forest.