塔里木河下游环境因子与沙漠化关系多元回归分析

Analysis on the Relationship between the Environmental Factors and the Desertification in the Lower Reaches of Tarim River by Multi-regression Models

塔里木河下游是新疆沙漠化最严重的区域之一。由于近 5 0a来人类不合理开发活动 ,导致 32 0km河道于2 0世纪 70年代开始断流 ,地下水位大幅度下降 ,生态系统受到深度“胁迫” ,由地下水维系的植被群落 ,已出现严重的退化现象 ,当地的生态环境日趋恶化 ,沙漠化面积呈逐年扩大的趋势。本文根据近两年来对塔里木河下游沙漠化的大量野外考察、取样和室内样品分析及微机处理 ,以塔里木河下游地下水的变化为主导因子 ,通过SPSS分析软件对引起塔里木河下游沙漠化的一些主要环境因子进行多元回归分析 ,建立了沙漠化初步评价的回归模型。该模型显示在塔里木河下游地区 ,地下水位和土壤含水量是影响塔里木河下游沙漠化过程的两个重要限制因子。

The lower reaches of Tarim River is one of the regions with the most serious desertification. Because of the irrational exploitation since recent 50 years in the Tarim River watershed, some serious environmental problems have occurred, they include the stream flow cut-off from the 1970's, drawdown of groundwater level in a high amplitude, serious intimidation to the ecological environment, serious degeneration of the vegetation communities relying on groundwater for existence, increasingly degeneration of the local ecological environment, enlargement of desertification, etc. In this paper, some main environmental factors of desertification in the lower reaches of Tarim River are analyzed by the multi-regression models, regarding the change of groundwater level in the lower reaches of Tarim River as the dominant factor and applying SPSS software based on the field investigation in recent years and laboratory analysis of the samples, and the regressive models for assessing the desertification in the lower reaches of Tarim River are developed. The results show that the groundwater level and the moisture content in soils are the main factors affecting the desertification in the lower reaches of Tarim River.