1980—2020年洱海流域土地利用变化及趋势预测研究

Land Use Change and Trend Forecast in Erhai Basin from 1980 to 2020

以洱海河流域为研究对象,探究其1980—2020年间土地利用变化及未来20年变化趋势。基于40年间5期土地利用数据,借助ArcGIS、IDRIS、Excel软件,利用土地利用变化指数、转移矩阵、土地利用演化信息图谱,分析洱海流域40年来的土地利用变化及相互转换;利用IDRIS的CA-Markov模型预测其未来20年土地利用变化。结果表明,1980—2020年间洱海流域土地利用变化呈多元上升趋势,耕地呈持续下降趋势,建设用地逐渐快速增长,综合土地利用年变化率呈上升趋势。CA-Markov模型预测结果表明,未来20年耕地面积有所下降,林地、建设用地面积有所上升,草地、水域、未利用地面积保持相对稳定。从土地利用演化信息图谱来看,土地利用转换主要集中在自然保护地范围外,保护地内土地利用变化主要集中在1990—2010年间,且变化不大。未来20年内城镇化持续扩张,主要集中在洱源盆地、凤羽盆地和海西坝子区域。

This paper studied land use changes in Erhai Basin from 1980 to 2020 and the trend of changes in the next 20 years.Based on 5 periods of land use data over 40 years,this paper used ArcGIS,IDRIS and Excel software to analyze the land use changes and their mutual transformations in Erhai Basin over the past 40 years from land use change index,transition matrix and land evolution information map,and used the CA-Markov model of IDRIS to predict land use changes over the next 20 years.The results showed that from 1980 to 2020,the land use change in Erhai Basin showed a diversified upward trend,with cultivated land continuously decreasing,construction land gradually increasing rapidly,and the annual comprehensive land use change rate showing an upward trend.The CA-Markov model prediction results indicated that the cultivated land area would decrease in the next 20 years,while the forest land and construction land area would increase,and the grassland,water area,and unused land area would remain relatively stable.From the evolutionary map,land changes were mainly concentrated outside protected areas,while land changes within protected areas were mainly concentrated between 1990 and 2010,and the changes were not significant.In the next 20 years,urbanization would continue to expand,mainly concentrated in the Eryuan Basin,Fengyu Basin,and Haixi Bazi area.