西藏色季拉山川滇高山栎种群结构与动态  

Population Structure and Dynamics of Quercus aquifolioides in Sejila Mountain,Tibet,China

作　　者：王国严[1,2] 罗建 徐阿生 庄颖梅[1] 

机构地区：[1]西藏农牧学院,西藏林芝860000 [2]西藏高原生态研究所,西藏林芝860000

出　　处：《林业科学研究》2011年第3期292-299,共8页Forest Research

基　　金：国家自然科学基金项目(30860026);西藏林芝高山森林生态系统定位研究项目资助

摘　　要：采用种群大小级结构、生命表、生命曲线和秩相关分析对西藏色季拉山川滇高山栎种群的结构与数量动态以及种群高度—环境关系的研究得出:川滇高山栎种群总体呈增长型,不同地段种群的年龄分布差异较大(P<0.001),种群表现出林隙更新和阶段性更新的特征,迹地型种群以大量同龄或近同龄林出现,幼苗缺失,呈现出偏途顶极的特征,存在被其他树种替代的可能。川滇高山栎存活曲线介于DeevyⅡ与DeevyⅢ型之间,整个生命过程出现4次死亡高峰,以幼苗进入幼树时期最为强烈(死亡率77.3%),高死亡率会带来高的生命期望值,种内资源竞争是影响个体寿命和造成种群波动的主要原因。环境因子对川滇高山栎种群高度的影响程度排序为:土壤湿度>年降水量>坡位>坡向>坡度>海拔,土壤湿度和年降水量是影响川滇高山栎种群高度分化的显著因子,另外种群对海拔的适应幅度较宽,对坡度响应不强,水分格局是影响个体增长和种群发展的重要因素。Quercus aquifolioides is a representative broadleaf evergreen species on the Qinghai-Tibet Plateau,which has a extensive,continuous distribution in the southeast Tibet forest region.It plays an important role on soil and water conservation of the alpine-gorge areas.The population structure,quantitative dynamics,the relationships between height and environment were studied using composition of size classes,life table,survival curve,and rank correlation analysis.The result indicated that：（1） the whole Quercus aquifolioides population took on a growing trend and the distribution of tree ages differed among plots（P0.001）,population regeneration better in gaps and was discontinuous in time domain.Slash-type population had approximately even-aged trees,showing the feature of disclimax,which would be possibly succeeded by another forest.（2） The survivorship curve was between Deevy typeⅡand Ⅲ.There were 4 mortality peaks in the tree＇s life,and the largest occurred while the seedlings growing into saplings（mortality reached 77.3%）.The high mortality might result in high life expectation,the main reason of individual lifespan and population fluctuation is intraspecific resource competition.（3）The degree order of six factors influencing the population height was：Soil moistureAnnual rainfullPositionSlope aspectSlopeAltitude,the soil moisture and annual precipitation had significant impacts on the population＇s canopy height differentiation.In addition,the population had a wide adaptation on altitude and a weak response to the slope.The spatial water pattern significantly affected the individual growing and population development.

关 键 词：色季拉山 川滇高山栎 种群结构 静态生命表 种群高度 环境 

分 类 号：S718.54[农业科学—林学]