基于GIS的伊犁河流域生态环境质量评价与动态分析

Assessment and dynamic analysis of the eco-environmental quality in the Ili River Basin based on GIS

生态环境质量评价是一项综合性、系统性研究工作,是合理开发利用资源、制定经济社会可持续发展规划和生态环境建设与保护对策的前提和基础。借助GIS技术,以县级行政区划为单元,利用2002和2004年遥感监测数据,运用综合指数评价法,从生物丰度、植被盖度、水网密度、土地退化和污染负荷5个方面,对伊犁河流域8县1市的环境质量现状进行了评价,结果表明:各县级行政区生态环境质量总体较为均衡,均处于一般等级水平,其中流域上游的新源县、巩留县和特克斯县相对较好。在此基础上探讨了生态环境质量综合评价指标体系在干旱区的适用性,比较分析2年期间不同生态环境质量等级的土地覆盖变化,数据表明伊犁河流域生态环境质量呈现"局部有所改善、总体缓慢退化"的趋势,并分析了研究区生态环境质量变化的内在原因。

The Ili River basin is located in the west of Xinjiang and on the north slope of the Tianshan Mountains. The administration divisions include eight counties and one city with an area of 5.63 × 10^4 km^2. As a comprehensive and systematic research work, to evaluate the eco-environmental quality is necessary for exploiting nature resources, Firstly, drawing plan of social and economic development, and protecting and constructing the eco-environment. this paper introduces a comprehensive evolution method of eco-environmental quality which consists of five elements including biological abundance, vegetation coverage, net-water density, land degradation and pollution load, and evaluate the environmental quality of 9 county administration districts in Ili River Basin with data of remote sense monitoring between 2002 and 2005 by GIS technology. The results show that the eco-environmental quality in each county is close in general and shares middle grade, among which Xinyuan, Gongliu and Tekesi county, which locate in the upper of Ili River Basin, have a better quality than the others. Secondly, the paper discusses the availability of the comprehensive evolution method in the arid area. Thirdly, the paper analyzes the dynamic trend of eco-environmental quality by land area change of different grade for natural geographical unit in 2 years. The results show that the eco-environmental quality in the Ili River Basin takes on the trend which improve partly and degrade slowly in general. In the last we explain the reason of the dynamic change in nature.