川西北江河源区生态环境脆弱性评价

Assessment of Ecological Environment Vulnerability in the River Source Area of Northwest Sichuan

为掌握川西北江河源区的生态环境脆弱性时空变化过程及土地利用对生态环境脆弱性的影响,利用集成遥感技术、地理信息系统技术,结合空间主成分分析法构建评价指标体系和评判模型,对2000-2015年川西北江河源区的生态环境脆弱性做出评价,并分析其与土地利用之间的关系。结果表明,川西北江河源区生态环境脆弱性整体呈现出好转的趋势,中度和重度脆弱面积在研究时间尺度内持续减少;生态环境脆弱性较为严重的区域基本分布在东部的若尔盖县和西部的石渠县;土地利用类型中建设用地、未利用地、耕地对环境脆弱性的恶化具有较大影响。表明近年来川西北江河源区退耕还林、退牧还草等生态保护政策已取得成效,但仍需加大环境治理力度。

The purpose of this paper is to understand the spatiotemporal change characteristics of ecological environment vulnerability and the impact of land use on ecological environment vulnerability. Remote sensing（RS）,geographic information system（GIS）,spatial principal component analysis（SPCA） were used to establish the evaluation index system and evaluation model to evaluate ecological environment vulnerability from 2000 to 2015,and analyze the relationship between ecological environment vulnerability and land use. The results showed that,the vulnerability of the ecological environment in the study area showed a trend of improvement,and the area of moderate and severe fragile continued to decrease in the study time scale.The areas with serious ecological fragility in the study area were mainly distributed in the eastern Ruoergai county and the wester Shiqu county. The building land, unused land and cultivated land had a great influence on the deterioration of environmental vulnerability. It is pointed out that ecological protection policies such as returning cultivated land to forests and returning grazing land to grassland in the northwest Sichuan river source area have been effective,but still need to increase the environmental management.