岷江上游地区生态环境脆弱性变化研究

Study on the change of eco-environmental vulnerability in the upper reaches of Minjiang River

为掌握岷江上游地区生态环境脆弱性变化状况,从地形、气候、植被等方面构建评价指标体系,并将RS,GIS技术与熵组合权重模型相结合,对该地区2000—2015年生态环境脆弱性进行评价与分析,结果表明:(1)该地区生态环境脆弱性整体呈现西部相对较高,东部较低的变化状况;(2)各脆弱区栅格比例呈现不同的差异,微度和重度占据最大和最小两端,轻度、潜在和微度的比例则呈现依次降低的趋势;(3)该地区中度及以上脆弱区的栅格比例仅约20%,轻度及以下区域占据绝大部分,客观上反映其生态环境整体处于中等脆弱水平;(4)15年内,脆弱性综合指数分别为2.5916,2.5710,2.5719和2.5373,生态环境质量整体向好的方向发展;(5)系列环保措施实施促进了整体好转,而大量水电基地的建设也对小部分区域变化产生干扰;(6)针对不同区域,实行不同保护与恢复重建措施,将有助于生态环境的好转。

In order to obtain the change of ecological environment vulnerability in the upper reaches of Minjiang River,the evaluation index system was constructed from topography,climate,vegetation and other aspects.RS,GIS technology and entropy combination weight model were combined to evaluate and analyze the ecological environment vulnerability in this region from 2000 to 2015.The main achievements were as follows:(1)the ecological environment vulnerability of this area showed a relatively high change state in the west and a relatively low change state in the east in the whole;(2)the proportion of grid in each vulnerable area was different,the fineness and weight occupied the maximum and minimum ends,and the proportion of mild,potential and micro showed the change of decreasing in turn;(3)the grid ratio of the moderate and above vulnerable areas was only about 20%,and the mild and below areas accounted for the vast majority,which objectively reflected that the overall ecological environment was at a moderate level;(4)in the past 15 years,the vulnerability composite index was 2.5916,2.5710,2.5719 and 2.5373,respectively,and the overall quality of ecological environment quality was improved;(5)the driving force analysis showed that the implementation of a series of environmental protection measures had promoted its overall improvement,and the construction of a large number of hydropower bases had also caused interference with the changes in small parts of the region;(6)according to different regions,the implementation of different protection and restoration and reconstruction measures would contribute to the improvement of the ecological environment.