色季拉山冷杉群落结构及物种多样性分析

采用实地调查的方法对西藏色季拉山冷杉(Abies Mill.)物种展开研究。结果表明,色季拉山冷杉群落乔木层有2种,灌木层有13种,草本层有28种。冷杉群落乔木层树木种类比较单一,除生长的优势种急尖长苞冷杉[A.georgei Hand.-Mazz.var.smithii(ViguiéGaussen)C.Y.Cheng,W.C.ChengL.K.Fu]外(重要值为77.7%),仅有伴生种西南花楸(Sorbus rehderiana Koehne)共生(重要值为22.3%);对灌木层和草本层阴坡、阳坡2个不同坡向生长的物种多样性进行对比分析,结果阳坡的Patrick丰富度指数R、Simpson多样性指数D和Shannon-Wiener多样性指数H′都高于阴坡;同时,随海拔高度升高,物种数量呈现减少的趋势。

Analysis on the Community Structure and Tree Species Diversity of Abies in Sygera Mountains

The Abies Mill.species in Sygera Mountains of Tibet was studied by field investigation.The results show that among the Abies communities in Sygera Mountains,there were 2 tree layer species,13 shrub layer species and 28 herbaceous layer species.The species of Abies communities in arbor tree was single,except for the advantage species A.georgei Hand.-Mazz.var.smithii (Viguié & Gaussen)C.Y.Cheng,W.C.Cheng & L.K.Fu (importance value 77.7％),there was only one companion species,Sorbus rehderiana Koehne (importance value 22.3％).Comparing the species diversity of shrub layer and herb layer on both shady and sunny slopes,the results showed that the richness index R,Simpson index D and Shannon Wiener diversity index H' of the sunny slope was all higher than that of the shady slope.Moreover,the diversity of species decrease with the increase of altitude.