土地利用和生态系统服务功能变化研究——以三峡库区大宁河流域为例

DYNAMICS IN LAND USE AND ECOSYSTEM SERVICE——A CASE OF DANING RIVER WATERSHED IN THREE GORGES RESERVOIR AREA

将土地利用类型分类为耕地、有林地(森林地)、灌木林地、草地、迹地、水体、建设用地和未利用地8类。以遥感数据为数据源,通过自动分类和人工解译相结合的方法获取了以上土地利用类型,并对三峡库区大宁河流域的土地利用变化过程和驱动力做了分析。以Costanza等人的全球生态系统服务价值的估测结果为基础,对各种地类生态服务功能价值重新赋值,进而估算近30年大宁河流域的生态服务价值,分析了其变化过程。结果表明:近30年,大宁河流域土地利用总的变化趋势是林、灌、草地经历了不断破坏和缓慢恢复的过程,耕地面积经历了先增后减,建设用地不断扩展。经济发展、人口增长和国家政策是土地利用变化的主要原因。生态系统服务功能经历了一个先损害后恢复的过程,表现为生态服务价值从1973年到1995年不断减少,而1995年到2002年连续增加。

In this paper, the land use was classified into eight types, namely forest land, bush land, sparsevegetation land, water land, construction land and unused land. Using the remote sensing images as the data source, types of land use were auto-classified and manually interpreted, with the detailed analysis on the process and driving forces of the changes in land use of Daning River Watershed in the Three Gorges Reservoir Area. Then the ecosystem service value of each kind of land use was reevaluated based on the result of Costanza＇s evaluation,and the ecosystem service values of the Daning River Watershed over last 30 years were calculated. The results indicated that over the last 30 years, the trend of the change of land use in Daning River Watershed was that forestland, bush land, and grassland experienced process from destruction to restoration, the area of farmland increased from early 70s of last century and then decreased gradually,and the construction land expanded unceasingly. The ecosystem service has changed from a damaged process to a resuming process, with the value of ecosystem service decreased from 1973 to 1995 and increased from 1995 to 2002.