基于GIS重庆岩溶地区生态环境脆弱度评价

重庆岩溶区属典型的生态环境脆弱区,宜耕地资源不足,土地退化严重,承受自然灾害能力低,使岩溶地区的社会经济发展和生态环境的协调性差,可持续发展能力弱。本文以重庆市岩溶地区为例,选择碳酸盐岩出露面积、山地面积、旱坡耕地面积、石漠化程度(包括轻度、中度和高度)、森林覆盖率、水土流失面积、土壤侵蚀模数、滑坡体积密度、垦殖指数、人均耕地面积、农业人口密度等13项生态环境脆弱度影响因子作为评价指标,利用层次分析法赋予指标权重,然后构建模糊数学模型对岩溶地区生态环境脆弱度进行评价研究,基于GIS技术对评价结果进行等级划分。结果表明: 重庆25个岩溶区县中潜在脆弱区县3个,轻度脆弱区县10个,中度脆弱区县6个,重度脆弱区县6个。 

GIS-BASED ECO-ENVIRONMENT VULNERABILITY ASSESSMENT IN CHONGQING KARST REGION

The karst regions in Chongqing are typical eco-environment vulnerable areas,where plowland is insufficient and degeneration of soil is serious,so the ability to endure the natural calamities is weak.Consequently,coordination between development of social economy and eco-environment is low,and the ability of sustainable development is infirm.This paper takes the karst areas of Chongqing as a case and selects 13 influencing factors to eco-environment vulnerability as assessment indicators,including earth surface of carbonate rock,area of mountainous region,area of slopping upland farming,degree of rock desertification(classified as gently,moderately,seriously),forest coverage,area of water and soil erosion,soil erosion modulus,density of landslip volume,cultivation index,area of farmland per person,density of agriculture population.And then,we uses analytic hierarchy process(AHP) to give weight for different assessment indicators.After that,a model of fuzzy mathematics was set up to analyze and evaluate the eco-environment vulnerability of karst areas,and the rank divisions towards the assessment results were obtained.Results indicate that there are 3 potentially vulnerable counties,10 gently vulnerable counties,6 moderately vulnerable counties and 6 seriously vulnerable counties among the 25 karst counties in Chongqing.