岷江流域生态脆弱性时空演变及影响因素分析

Analysis on the spatial and temporal evolution and influencing factors of ecological vulnerability in Minjiang River Basin

岷江流域位于四川盆地西部边缘过渡地带,是西南地区典型生态脆弱区之一,探索其生态环境脆弱性的时空演变及影响因素对维持四川省生态系统稳定性至关重要。利用“压力-状态-反应”(PSR)模型,收集多源数据,并利用熵值-Critic法评估权重,分析2012—2022年岷江流域的生态环境时空演变特征,采用地理探测器模型评估流域生态脆弱性的影响因素。结果表明,(1)岷江流域在研究时间段内整体脆弱性先升后降,重度、极度脆弱面积在中部先扩张后收缩,轻度脆弱面积自2017年后以成都市区为中心面积陡增,流域生态环境显著改善;且具有北部高-高聚集,中部、南部低-低聚集的空间分布特征。(2)在政策因素相对稳定的条件下,影响岷江流域生态脆弱性的主要因素是年均降水量和高程,且气候因素对生态脆弱性的影响程度逐步增强。研究成果可为岷江流域生态环境修复和“两山”建设提供理论依据。

The Minjiang River Basin,locating in the transition zone on the western edge of the Sichuan Basin,is one of the typical ecological fragile zones in Southwest China.It is very important to explore the spatial and temporal evolution of its ecological environment vulnerability and its influencing factors to maintain the stability of the ecosystems in Sichuan Province.Using the pressure-state-response(PSR)model,remote sensing,meteorological and social statistics data were collected,and the weights were evaluated using the Critic Method-Entropy Value Method,and finally an ecological vulnerability evaluation system for the Minjiang River Basin was constructed.The spatial and temporal evolution characteristics of the ecological environment vulnerability in the Minjiang River Basin from 2012 to 2022 were analyzed,and the influencing factors of the ecological vulnerability of the basin were evaluated by using the geographic detector model.The results showed that:(1)During the study period,the overall vulnerability of Minjiang River Basin increased first and then decreased,and the severe and extremely vulnerable areas expanded first and then shrinked in the middle.Since 2017,the area of mild vulnerability had increased sharply with Chengdu as the center,and the ecological environment of the basin had improved significantly.And it had the spatial distribution characteristics of high-high concentration in the north and low-low concentration in the middle and south.(2)Under the condition of relatively stable policy factors,the main factors affecting the ecological vulnerability of Minjiang River Basin were the average annual precipitation and elevation,and the effects of climatic factors on ecological vulnerability was gradually enhanced.The research results could provide theoretical basis for ecological environment restoration and"Two Mountains"construction in Minjiang River Basin.