急尖长苞冷杉林林线附近群落结构与物种多样性  

Community Structure and Species Diversity of Abies georgei var.smithii Forest near the Timerline

作　　者：张晓娟[1] 罗大庆[1,2] 

机构地区：[1]西藏农牧学院高原生态研究所,西藏林芝860000 [2]西藏林芝高山森林生态系统国家野外科学观测研究站,西藏林芝860000

出　　处：《西北林学院学报》2013年第2期1-7,共7页Journal of Northwest Forestry University

基　　金：2013年西藏自治区科技计划课题“藏东南高山林线特征与气候变化研究”;西藏大学农牧学院“211工程”三期“高原生态学”项目(XZA-211(3)-071012-06)

摘　　要：急尖长苞冷杉(Abies georgei var.smithii)是西藏东南部高山林线区森林群落的主要建群树种,分布于色季拉山海拔3 600～4 400m区域,为阴坡高山林线的优势树种。在藏东南色季拉山东坡急尖长苞冷杉林林线附近海拔4 000～4 400m地带进行样地样方调查的基础上,分析急尖长苞冷杉群落的物种组成、物种丰富度(S)、Simpson指数(D)、Shannon-Wiener指数(H')、均匀度指数(Ea)、Jaccard指数(Cj)、Cody指数(βc)以及种群结构与生长特征。结果表明:1)在林线5个海拔的调查样地中,共有种子植物26种,分属16科20属;随海拔梯度的升高,植物的科、属、种的数量总体呈减少趋势,灌木层和草本层的丰富度亦呈相似的趋势;2)林线附近的灌木层和草本层植物的α多样性与海拔总体呈负相关;3)在生境转折带的4 100～4 200m之间Jaccard指数(Cj)最低,Cody指数与海拔呈负相关;4)林线附近的急尖长苞冷杉种群总体呈稳定的金字塔型结构;5)在林线附近,海拔4 200m的急尖长苞冷杉的分布与生长状况相对较优。Abies georgei var.smithii is a main constructive species of the forest communities at alpine timerline in southeast area of Tibet.It is also the dominant tree species on the shady slope in this area,and distributed between 3 600 to 4 400 m above sea level at the Mt.Sejila.Based on a comprehensive investigation on A.georgei population that distributed between the altitudes of 4 000 to 4 400 m,an analysis was carried out on the species composition,species richness,Simpson index,Shannon-Wiener index,Evenness index,Jaccard index,Cody index,changes in the structure,and growth characteristics.The results were reported as follows.1） There were 26 species of wild seed plants belonging to 16 families and 20 genera in sampling plots.The number of families,genera and species decreased with the increase of altitude.Species richness of shrubs and herbs also demonstrated the same trend.2） Diversities of shrubs and herbs negatively correlated to altitude.3） The lowest values of Jaccard index appeared at the altitudes of 4 100 to 4 200 m,and the Cody indexpresented a negative correlation with altitude.4） The population structure demonstrated a relatively stable pyramid.5） The growth situations around 4 200 m above sea level were excellent.

关 键 词：西藏 色季拉山 林线 急尖长苞冷杉 群落结构 物种多样性 

分 类 号：S791.140.2[农业科学—林木遗传育种]