基于SRP模型的地质灾害易发区生态脆弱性评价

Ecological vulnerability assessment of geological disaster prone area based on SRP model

以甘肃省舟曲县为研究对象,以2010,2015和2020年遥感影像数据、地形数据、气象数据、地质灾害数据以及社会经济数据等为基础,结合SRP模型构建评价体系,采用层次分析法、空间自相关、地理探测器等方法,对舟曲县生态环境脆弱性进行定量评价与分析.结果表明:从县域尺度来看,2010—2020年舟曲县生态处于中等脆弱水平,在空间上呈现“北低南高,东低西高”的特征,时间上呈现“极度、重度脆弱区面积明显减少,中度脆弱区面积显著增加”趋势,整体向好趋势明显;从乡镇尺度来看,生态脆弱性状况均呈好转趋势,各乡镇生态脆弱性等级变化以极度、重度脆弱区减少,中度脆弱区增加为主;生态脆弱性空间集聚效应减弱,高高集聚类型乡镇由4个减少至3个,低聚集类型乡镇由1个增加至2个;生态脆弱性分布与变化主要受土壤、气象、地形地貌、人类活动以及地质灾害等因素综合影响,其中年降水量、地质灾害易发点密度和距离道路距离3个因子解释力最强,地形起伏度、坡度和距离河流距离3个因子解释力最弱.

Taking Zhouqu County,Gansu Province as the research object,based on remote sensing image data,terrain data,meteorological data,geological disaster data,and socio-economic data in 2010,2015,and 2020,combined with SRP model,an evaluation system was constructed.Analytic hierarchy process,spatial autocorrelation,geographic detectors,and other methods were used to quantitatively evaluate and analyze the ecological environment vulnerability of Zhouqu County.The results show that at the county scale,Zhouqu County s ecology is at a moderately fragile level from 2010 tO2020.In spatial terms,it manifests the pattern of“low vulnerability in the north and high in the south,low in the east and high in the west”.Temporally,it demonstrates the tendency of a notable decrease in the area of extremely and severely vulnerable regions,coupled with a substantial increase in the moderately vulnerable areas-a clearly positive overall trend.From the perspective of township scale,the ecological vulnerability showed a trend of improvement.The change of ecological vulnerability level in villages and towns is mainly in the extremely and severely vulnerable areas,while the moderately vulnerable areas increase.From 2010 tO2020,the spatial agglomeration effect of ecological vulnerability in Zhouqu County weakens.The number of towns with high-high agglomeration type decreases from 4 tO3,and the number of towns with low-low agglomeration type increases from 1 tO2.The ecological vulnerability in Zhouqu County is comprehensively influenced by soil,meteorological conditions,landforms,human activities,and geological hazards,considering the perspective of driving factors.Among them,annual precipitation,density of geological hazard prone points and distance from road have the strongest explanatory power.While topographic relief,slope and distance from river have the weakest explanatory power.