三峡水库坝区生态屏障区近25年土地利用变化评价

通过研究三峡水库坝区生态屏障区近25年来的土地利用变化,揭示其时空变化规律及驱动机制,为坝区生态屏障区土地资源的合理开发利用及生态系统管理提供科学依据。运用RS和GIS技术对1993年、2006年和2018年3期Landsat遥感影像进行处理,得到土地利用类型分布图;综合运用土地利用变化量、变化幅度和转移矩阵等定量指标,对三峡水库坝区生态屏障区1993—2018年间的土地利用变化进行分析。结果表明:1993年以来,三峡水库坝区生态屏障区土地利用结构变化明显,表现为林地、园地和水域的增加,耕地的大幅减少,其中水域面积增加幅度高达183.0%,而耕地面积减少幅度达68.9%;土地利用转移特征结果显示,水域、园地的增加都主要由耕地、林地转化而来,林地、建筑用地的增加主要由耕地转化而来,而未利用地向各方面用地类型转化;三峡水库坝区生态屏障区1993—2006年水域变化程度远大于2006—2018年,其他类型变化幅度相近。总体而言,三峡工程的建设、城镇化发展、农林产业结构调整和生态保护是三峡水库坝区生态屏障区土地利用变化的主要原因。

Evaluation of Land Use Change in the Ecological Barrier Zone of the Dam Area of the Three Gorges Reservoir in Recent 25 Years

By studying the land use change in the ecological barrier area of the Three Gorges Reservoir dam area in the past 25 years, the temporal and spatial variation characteristics and driving mechanisms were revealed, which could provide a scientific basis for the rational development and utilization of land resources and local ecosystem management. The Landsat remote sensing images of 1993, 2006 and 2018 were processed using RS and GIS techniques to obtain the distribution map of land use types. Combining the spatial analysis tools of geographic information system and the analysis method of transfer characteristics, this study analyzed the land use change in the ecological barrier zone of the Three Gorges Reservoir dam area from 1993 to 2018. The results showed that since 1993, the land use structure of the ecological barrier zone in the dam area of the Three Gorges Reservoir has changed significantly, showing an increase in forest land, garden plot and water area, and a significant reduction in cultivated land. The increase in water area was as high as 183.0%, while the reduction in cultivated land area was 68.9%. The transfer characteristics of land use indicated that the increase of both water area and garden plot were mainly from cultivated land and forest land. The increase of forest land and construction land were mainly from the conversion of cultivated land, and unutilized land was transformed into different types of land use. The water area in the ecological barrier zone of the Three Gorges Reservoir dam area from 1993 to 2006 was much larger than that in 2006-2018, while the other types of land use change were similar. In general, the construction of the Three Gorges Project, the development of urbanization, the structural adjustment of agriculture and forestry industry and ecological protection were the main reasons for the land use changes in the ecological barrier zone of the Three Gorges Reservoir dam area.