岷江上游暗针叶林采伐迹地人工混交林群落结构

STRUCTURES OF THE ARTIFICIAL MIXED FORESTS IN THE CLEAR CUT AREA OF SUBALPINE DARK CONIFEROUS FORESTS ON THE UPPER BRANCH OF THE MINJIANG RIVER

对四川岷江上游高山峡谷区暗针叶林采伐迹地年龄为２０～４０ 年的人工混交群落结构进行了研究。结果是，（１）群落中各层次物种盖度的大小相互影响、相互制约，而林下（各）层次物种盖度的大小主要取决于其上（各）层盖度（或郁闭度）的大小。（２）人工重建的群落所能容纳的物种数及物种在群落中的分布状况主要取决于乔木物种郁闭度、海拔高度及经营强度。（３）群落中出现大量的耐荫植物，先锋灌丛植物已被抑制或淘汰。（４）乔木物种的胸径和树高生长规律都表现为白桦＞ 云杉＞ 川西云杉＞ 四川红杉＞ 青杄。

The structures of the artificial mixed forests with the age of 20～40 a in the clear cut area of subalpine dark coniferous forests on the upper branch of the Minjiang river have been studied in this paper.Main results indicated:(1) The coverage of each layer (tree,shrub,herb et al.) of the artificial forests were interrelated and interacted on one another,however,the coverage of the under layer/layers mainly depended on the coverage of the upper layer/layers or tree canopy.(2) The number and distribution of the species in the artificial forests were mainly decided by tree canopy,altitude and management class.(3) Many shady tolerant plant species have occurred naturally,while the pioneer shrub species have been limited or superseded.(4) The growth laws of the D.B.H.and height of trees were Betula platyphylla>Picea asperata>Picea balfouriana>Larix mastersiana>Picea wilsonii.