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本文应用ＴＷＩＮＳＰＡＮ等级分类和ＰＣＡ，ＤＣＡ排序技术对甘肃酒泉地区的天然胡扬林分进行了分类和排序，并将排序的结果与环境因子之间进行了回归分析。结果表明，（１）甘肃酒泉地区的胡杨天然林分可以被划分为４个类型，这四个类型在生长更新状况及生境条件方面存在着较显著的差异，而在林分的龄级结构上并无显著区别．（２）酒泉地区胡杨生长的主要限制因子是地下水位，水矿化度，土壤总盐量及ＣＬ￣－含量，ＰＨ值不是影响胡杨林生长的主要限制因子。而气候因子对酒泉地区胡杨林的影响并不大。
In this paper, we classified and sorted the natural Hu Yang forest stand in Jiuquan area of Gansu Province by using TWINSPAN classification and PCA and DCA ranking techniques. Regression analysis was conducted between the results of ranking and environmental factors. The results showed that: (1) Natural Populus euphratica forest in Jiuquan area of Gansu Province can be divided into four types. There are significant differences in growth and renewal conditions and habitat conditions among these four types. However, There is no significant difference. (2) The main limiting factors for the growth of Populus euphratica in Jiuquan area are groundwater level, water salinity, soil total salt content and CL¯-content, and PH value is not the main limiting factor to the growth of Populus euphratica forest. The climatic factors on Jiuquan area Populus forest impact is not large.