基于土地利用的三峡库区近30年生态系统服务价值时空变化特征

为了分析和探究三峡库区生态系统服务价值的时空变化特征,以Landsat TM/Landsat 8 OLI遥感影像为基础数据,运用RS和GIS技术提取了研究区1986年、1995年、2000年、2007年、2010年和2018年的土地利用数据,并运用土地利用动态指数模型和土地利用程度指数模型对其土地利用类型的变化趋势进行了分析。另一方面,核算了研究区相应年份的生态系统服务价值,并分析了其时空演变特征,同时对土地利用程度与ESV的相关关系进行了分析。结果表明:(1)1986-2018年,三峡库区耕地、林地和草地面积呈现减少的趋势;水域、建设用地和未利用地面积呈现增加的趋势;(2)不同土地利用类型的变化速度具有差异性,其中,建设用地和水域变化较快,耕地、林地、草地和未利用地变化较慢;(3)1986-2018年,三峡库区生态系统服务价值总量由1639.56亿元持续增长到1662.01亿元,整体增幅1.37%;(4)研究区ESV具有空间正向自相关性,其中高值区聚集明显,中低值区分区域相邻布局;(5)土地利用程度与ESV存在强烈的正相关关系。三峡库区近30年来的生态系统服务价值整体上有所提升,生态状况有所改善,但区域间差异较大,局部地区仍需特别关注,生态系统服务价值与土地利用之间存在着密切相关性。

Spatial and Temporal Changes of Ecosystem Service Value in the Three Gorges Reservoir Area in the Past 30 Years Based on Land Use

In order to analyze and explore the spatial and temporal variation characteristics of ecosystem service value(ESV)in the Three Gorges Reservoir area,based on Landsat TM/Landsat 8 OLI remote sensing image,the land use data of 1986,1995,2000,2007,2010 and 2018 in the study area were extracted by using RS and GIS technology,and the change trend of land use type was analyzed by using dynamic index model and land use degree index model.On the other hand,the ecosystem service value of the study area in the corresponding years was calculated,its temporal and spatial evolution characteristics were analyzed,and the relationship between land use degree and ESV was analyzed.The results show that:(1)from 1986 to 2018,the areas of cultivated land,forestland and grassland in the Three Gorges Reservoir area showed a decreasing trend;the water area,construction land and unused land area showed an increasing trend;(2)the change rates of different land use types were different,among which the construction land and water area changed faster,while the cultivated land,forestland,grassland and unused land changed slower;(3)in the period 1986-2018,the total value of ecosystem services in the Three Gorges Reservoir area continued to increase from 163.956 billion yuan to 166.201 billion yuan,with an overall growth rate of 1.37%;(4)ESV in the study area had a positive spatial autocorrelation,in which the high value areas clustered obviously and the low value areas were adjacent;(5)there was a strong positive correlation between land use and ESV.In the past 30 years,the ESV of the Three Gorges Reservoir area had been improved as a whole,and the ecological situation had been improved.However,there were great differences among regions,special attention should be paid to some specific regions;there was a close relationship between the ecosystem service value and land use.The results of this study can provide reference for the sustainable utilization of land resources and ecological environment in the Three Gorges Reservoir area.