锦屏水电站植被数量分类与排序

以锦屏梯级水电站大河湾段植被为研究对象,以河流流向为基础布置样方,将50个样方物种重要值及其环境因子进行TWINSPAN数量分类和DCA排序,结果显示:(1)由TWINSPAN数量分类将植被划分为7种类型,雅致雾水葛(Pouzolzia elegans)灌草群落为该区域的主要群落.(2)以TWINSPAN数量分类为基础的DCA二维排序图将样方分为6个生态类型,DCA 二维排序图横轴从左至右海拔高度逐渐降低;排序纵轴由下至上坡度逐渐升高.(3)以TWINSPAN数量分类在DCA排序图中有明确的分布范围和界限,DCA排序与TWINSPAN数量分类结合使用,能很好反映群落与环境因子间的生态关系.

Quantitative classification and ordination of Jinping hydropower station, Sichuan Province,China

A survey of the Dahe Bay vegetation in Jin-ping cascade hydropower station setting along the river stream in Sichuan province, China, was performed. A total of 132 plant species and 4 environmental factors in 50 sample quadrats were recorded. Assemblages of Jin-ping Dahe Bay were classified using two-way indicator species analysis (TWINSPAN), ordinating by detrended correspondence analysis (DCA). Seven vegetation assemblages were divided by TWINSPAN classification, in which Pouzolzia elegans shrub grassland was the dominant community in this area. The DCA two-dimension plot based on the TWINSPAN classified the samples into six ecotypes. On the horizontal axis the altitude decreased gradually from left to right, while the vertical axis saw the slope increased down to up. TWINSPAN classification showed explicit distribution scope in DCA ordination plot, and this could better reflect the relationships between communities and environmental factors when combined with TWINSPAN quantitative classification.