阔叶红松林林隙结构与树种多样性关系研究

Correlation between gap structure and tree diversity of mixed-broad-leaved Korean pine forests in northeast China.

对阔叶红松林林隙与林下不同层次树种多样性进行比较,探讨林隙大小及发育阶段与树种多样性间的关系.结果表明,林隙与林下树种多样性存在显著差异(P<0.01).与林下相比,林隙更新层树种多样性、丰富度和均匀度增大,生态优势度减小(P<0.01);演替层树种多样性、丰富度和均匀度减小,生态优势度增大(P<0.0001).林隙中不同层次树种多样性随着林隙大小呈现出相反的变化趋势.长白山阔叶红松林林隙演替层树种多样性和丰富度总体上呈单峰形变化,中等大小林隙(100～250m2)中树种多样性和丰富度较高,生态优势度较小.而更新层树种多样性和均匀度在≥250m2和<100m2的林隙中最大,在200～250m2的林隙中最小;生态优势度在200～250m2的林隙中达到最大.更新层和演替层树种对林隙面积大小反应不同,有利于更新层幼苗建立的林隙面积并不是演替层幼树发育和成活的最适面积;随林隙年龄的增加,更新层和演替层树种多样性在不同层次上呈互补关系.

This paper studied the regeneration of tree species in the gaps of broad-leaved Korean pine forest, with the tree diversity in gaps and under closed canopy compared, and the relationship between biodiversity and gap structure analyzed. The results indicated that there was a significant difference between tree species diversity in gaps and under canopy （P 〈 0.01 ）. In regeneration layer, the biodiversity in terms of Shannon-Wiener, evenness, and abundance indices was higher in gap community than under forest canopy, while the dominance of certain species in terms of Simpson＇s dominance index was increased from gaps to closed canopy （P 〈 0.01）. The biodiversity of succession layer in gaps and under closed canopy had an opposite trend. Tree species diversity of different layers reacted differently to the change of gap size class, e. g., Shannon-Wiener and abundance indices were higher, but Simpson＇s dominance index was the lowest in the succession layer of medium-size gap（100-250 m^2） in broadleaved Korean pine forest of Changbai Mountain. The Shannon-Wiener index and evenness index reached the highest in the size of ≥250 m^2 and 〈 100 m^2, and reached the lowest in the size of 200 -250 mz in regeneration layer. Simpson＇s dominance index reached the highest in the size of 200-250 m^2. On the whole, tree species of different layers reacted differently to the change of gap size class, and the gap size class with more seedlings was not corresponding to the size class containing more medium-size trees. With gaps aging, tree diversity indices in the two layers behaved reciprocally.