西北干旱区生态脆弱性时空演变分析

Analysis on spatio-temporal evolution of ecological vulnerability in arid areas of Northwest China

西部大开发政策实施以来,随着社会经济的发展和环境政策的调整,西北干旱区生态环境发生深刻变化。基于西北干旱区生态本底特征,选取土壤、地形、气候并结合夜间灯光数据构建西北干旱区生态脆弱性评价体系,运用空间主成分分析法(SPCA)、地理探测器对西北干旱区2000、2007、2012、2018年生态脆弱性时空演变及驱动力进行分析。结果表明:(1)从西北干旱区生态脆弱性时空演变特征来看,研究区生态脆弱性以重度脆弱性为主;从不同土地利用脆弱性来看,微度脆弱区以草地、林地为主,轻度脆弱区以草地为主,中度脆弱区和重度脆弱区以未利用地为主,18年来研究区生态脆弱性整体保持不变;(2)影响西北干旱区生态脆弱性分异的主导因素包括土壤有机质含量、地形位指数、气温、降水、夜间灯光指数,各因素对生态脆弱性的平均决定力分别为0.63、0.36、0.27、0.26和0.22。(3)基于生态脆弱性监测结果和驱动因素分析,将西北干旱区划分为5个生态功能区:生态核心保护区、生态综合监测区、生态优化关注区、生态恢复治理区、生态潜在治理区,并提出相应管理方案。研究可以为干旱区生态环境保护提供借鉴。

With the development of social economy and the adjustment of environmental policies, the ecological environment in the arid areas of Northwest China has undergone profound changes since the western regions development policies. This paper selects soil, topography, climate and night lighting data to construct ecological vulnerability assessment indicators based on the ecological background characteristics of the arid areas of Northwest China, which was analyzed the spatio-temporal evolution and motivation of ecological vulnerability by Spatial Principal Component Analysis(SPCA) and geographic detector in 2000, 2007, 2012, and 2018. The results showed that(1) from the spatio-temporal evolution of ecological vulnerability, the research area was mainly dominated by heavy vulnerability. Over the past 18 years, the ecological vulnerability of the study area has remained unchanged. From the perspective of different vulnerability of land use types, grassland and woodland are the slight vulnerability, grassland is the light vulnerability, and unused land is the moderate vulnerability and heavy vulnerability.(2) The dominant factors affecting ecological vulnerability differentiation include soil organic matter content, topographic level index, temperature, precipitation and night light index. Their average power determinant values to ecological vulnerability differentiation are 0.63, 0.36, 0.27, 0.26 and 0.22.(3) Based on the monitoring results of ecological vulnerability and analysis of driving factors, we divide the arid areas of Northwest China into five ecologically functional zones: coreareas of ecological protection, ecological comprehensive concern areas, ecological optimal-concern areas, ecological restoration management areas, and ecological potential management areas. The corresponding management plans are proposed. This study can provide reference for ecological environmental protection in arid areas.