基于RS和GIS巫山县20年土地利用特征变化及其预测研究

Analysis and Forecast of Land Use Change Characteristics in Wushan County from 1990 to 2010 Based on RS and GIS

巫山县地处三峡库区腹地,不仅是三峡移民安置区重点建设区域之一,更是研究三峡库区土地利用变化的典型个案。以巫山县1990年和2010年的Landsat TM遥感数据为主要数据源,基于RS和GIS技术获取研究区的土地利用数据,应用土地利用变化模型探究该区域20年间土地利用时空演变特征,借助Markov模型建立其土地利用格局预测,探究今后土地利用类型变化特征和发展趋势。结果表明:研究区地利用类型总体呈现出以林地、草地和耕地为主体的农林生产格局现状;20年间林地、草地、园地、水域和居民工矿用地面积增加,耕地和未利用地面积减少,水域和耕地面积增加和减少的最多,分别为47.67km^2,136.10km^2;林地和水域具有较高的未变化率(保留率),未利用地变化率最小,林地和耕地之间具有较高的转换率,林地新增面积最大,变化速率最小,居民工矿用地变化速率最大;2090年后,研究区土地利用基本达到相对稳定状态,林地、耕地、草地、水域、居民工矿用地、未利用土地和园地的面积比重分别为52.96%,6.15%,26.69%,8.71%,1.38%,0.04%和3.97%。

Wushan County is located in the hinterland of the Three Gorges Reservoir area, is also one of the key construction areas of the Three Gorges resettlement area, further, is the typical sample of land use in Three Gorges Reservoir area. Therefore, We took Wushan County as the study area, and used the Landsat TM remote sensing images in 1990 and 2010 as the main data source to explore the spatial-temporal evolution during 20 years based on RS and GIS technology and other relative data, the land use change model, and used the Markov model to forecast the change characteristics and development trend in future. The results showed that the total areas of forestland, grassland and cropland occupied the dominate situation, and formed the current land use pattern; during the 20 years, the areas of forestland, grassland, orchard, water bodies and built-up land increased, on the country, the cropland and unused land decreased. Meanwhile, the increasing and decreasing areas of water bodies and cropland were the greatest, which accounted for 47. 67 km^2 and 136.10 km^2 , respectively. The forestland and water bodies had the high reserving rate, while the reserving rate for unused land was least, meanwhile, the transformation ration between forestland and cropland was higher, the adding area of forestland was maximum, the change rate of forestland was minimum, and change rate of built-up land was maximum. After 2090, the land use will reach the relatively stable state in the study area, which means that the percentage of forestland, cropland, grassland, water bodies, built-up land, unused land and orchard will be 52.96%, 6.15%, 26.69%, 8.71%, 1.38%.0.04% and 3.97%, respectively.