车八岭国家级自然保护区甜槠林群落恢复的研究
Study on Recovery of Castanopsis eyrei Community in Chebaling National Reserve
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摘要: 1983-2003年间对车八岭国家级自然保护区设立的固定样地进行了4次调查,对中亚热带常绿阔叶林甜槠 Castanopsis eyrei 林群系在保护状态下的群落恢复情况做了研究. 结果表明:群落蓄积量达516 m3/hm2,甜槠对群落的蓄积量贡献率最高可达70%,甜槠、木荷 Schima superba 和米槠 Castanopsis carlesii 的蓄积量分别为296.55、182.55和98.25m3/hm2;相比较而言,米槠的幼树对光照强度要求最低,但是从幼树到成树的过程中死亡率最高,甜槠幼树的成长比米槠幼树需要的光照强度大,但是甜槠生长过程中死亡率较小,木荷幼树对光照的需求介于米槠和甜槠之间,从幼树到成树的过程中,死亡率也介于米槠和甜槠之间;群落中高度2 m以下的幼树是树木生长最快的阶段,10 m以上的立木生长速度变慢,或者死亡率迅速上升,随着群落的恢复,较高的立木所占的比例增加,群落中的立木对群落上层空间的利用率增加;密度、丰富度和均匀度三者密切相关,密度小则丰富度小、均匀度变大;在群落的恢复过程中,群落多样性指数在下降的同时存在较大的波动.Abstract: A study on recovery of Castanopsis eyrei community in Chebaling National Reserve based on data from 4 surveys on the permanent sampling plot was carried out from 1983 to 2003, and results were as follows. The species Castanopsis eyrei could contribute as high as 70% to community volume that could reach as high as 516 m^3/hm^2. In comparison, young trees of the species C. carlesii required the least radiation but mortality was the highest when they grew up, otherwise young trees of the species C. eyrei showed opposite state, and young trees of the species Schima superba hold the medium position between the two values of the two species. The trees blow 2 m grew the fastest and that above 10 m grew slower or mortality became higher rapidly. Percent of higher trees and utilization to higher room in the community ascended in the process of recovery. The 3 indexes density, richness and evenness indicated compatatively close affinities. The diversity index shows a descending tendency with comparatively robust fluctuation.