乌蒙山峨眉栲、华木荷群落特征研究

乌蒙山位于中国西部半湿润常绿阔叶林与东部湿润常绿阔叶林交界区,是云南省唯一分布峨眉栲、华木荷群系(Formation Castanopsis platyacantha,Schima sinensis)的地区,该群系处于中国西部常绿阔叶林向东部常绿阔叶林过渡的地带,群落更加复杂多样。为了更深入地了解该群系的群落特征,同时找出其与东部湿润常绿阔叶林的联系,该文对该类型群落进行了数量分类研究,分析了聚类归并的各群落类型的乔灌优势种特征(径级结构、高度结构和重要值),同时采用DCA,CCA和DCCA排序分析进行群落特征分异的环境解释,并与四川峨眉山同类群落进行特征对比。结果表明:(1)乌蒙山峨眉栲、华木荷群落可划分为6个类型:峨眉栲群落,峨眉栲、华木荷群落,峨眉栲、十齿花群落,水青冈(Fagus longipetiolata)、华木荷、峨眉栲群落,华木荷、硬斗石栎(Lithocarpus hancei)群落,十齿花(Dipentodon sinicus)、华木荷群落。(2)乌蒙山峨眉栲、华木荷群落中,峨眉栲大树比例较高,华木荷小苗数量巨大,灌木层常以竹类为优势种。(3)海拔、坡度和太阳年辐射值是影响群落分布的主导因素。(4)峨眉山同类群落中优势种种群呈稳定型或增长型,而乌蒙山峨眉栲、华木荷群落中,峨眉栲和水青冈呈现下降型的特点。

Community characteristics of Castanopsis platyacantha, Schima scinensis forest in Wumeng Mountain

Wumeng Mountain is located in the joint zonation between western semi-humid evergreen broad-leaved forest and eastern humid evergreen broad-leaved forest in China. Formation Castanopsis platyacantha, Schima sinensis is a typical forest in this area with complex and diverse types that are only occurrence of Yunnan. In order to understand the community characteristics of this formation in more details, and to find out its relationship with the eastern moist evergreen broad-leaved forest, in this paper, we made clustering analysis on the basis of canopy and shrub layer species. And then, we analyzed the dominant species in tree and shrub layers by DBH class structure, height class structure, and importance value, and carried out ordination analysis by DCA, CCA, and DCCA to reveal the relationship between community features and environmental gradients. Finally, we compared the communities with the similar ones in Emei Mountain. The results were as follows:(1)Castanopsis platyacantha, Schima sinensis community in Wumeng Mountain could be divided into six types: Castanopsis platyacantha community, Castanopsis platyacantha, Schima sinensis community, Castanopsis platyacantha, Dipentodon sinicus community, Fagus longipetiolata, Schima sinensis, Castanopsis platyacantha community, Schima sinensis, Lithocarpus hancei community, and Dipentodon sinicus, Schima sinensis community.(2)There was a large proportion of Castanopsis platyacantha trees in old age, and a great number of seedlings of Schima sinensis in the community. Meanwhile, bamboo species were tyipical dominant in the shrub layer.(3)Community patterns were mainly influenced by elevation, slope, and annual solar radiation.(4)Dominate tree species'' population structures of similar communities in Emei Mountain were stationary or expansive type, but those were characteristics of constrictive type in Wumeng Mountain.