三江源地区生态环境脆弱性评价

Evaluation of ecological environment vulnerability for Sanjiangyuan area

三江源地区的生态问题对全国经济和生态具有十分重要的影响,研究、分析其生态环境脆弱性具有重要的理论和现实意义。本文基于生态敏感性-生态恢复力-生态压力概念模型(SRP),选取了气温、降水、地形起伏度等16个评价指标,使用层次分析法(AHP)与主成分分析法相结合的手段,建立了三江源地区生态环境脆弱性评价指标体系,通过计算生态环境脆弱性指数(EEVI)对研究区生态环境进行定量分析与评价。结果表明:三江源地区生态环境以中度脆弱区为主,所占面积比例为45.55%,轻微、轻度、重度、极度脆弱区分别占总面积的5.76%、23.12%、20.14%和5.43%,重度与极重脆弱区集中分布在地形复杂的西北部裸地、低植被覆盖地带及人口、经济活动压力较大的东北部地区。

The ecological situation in Sanjiangyuan area has an important influence on China＇ s national economy and ecology. Besides, studies on the ecological environment vulnerability also have its own theoretical and practical significance. Based on ecological sensitivity-resilience-pres- sure （SRP） conceptual model, we selected sixteen evaluation indices （including temperature, precipitation, topography, etc. ） and established the indicators system of ecological vulnerability evaluation in Sanjiangyuan area using the AHP method and the principal component analysis （PCA） method. Through calculating the ecological environment vulnerability index （EEVI）, we conducted vulnerability analysis and evaluation of ecological environment in the study area. The results showed that, in the study area, moderately vulnerable areas occupied 45.55% of the total, while the slightly, lightly, heavily and extremely vulnerable areas occupied 5.76%, 23.12%, 20.14% and 5.43% respectively. The heavily and extremely vulnerable areas are primarily located in the bare soil and low vegetation coverage zones of the northwest part of Sanjiangyuan area and in the northeast part under the greater pressure of large population and economic activities.