2000-2010年中国退牧还草工程区土地利用/覆被变化

在3S技术支持下,结合景观格局定量分析方法,基于30 m分辨率的土地利用/覆被数据,对中国退牧还草工程区2000-2010年土地利用/覆被时空分布特征进行研究。通过利用土地利用转移矩阵和动态度来判定土地利用变化的速度和区域差异,并在斑块类型和景观水平上分析研究区景观格局特征,探讨土地利用格局变化的生态效应。结果表明：①近10年来,研究区土地利用/覆被类型以草地和其他类用地为主,整体内部结构稳定少动。草地变化面积仅占2000年草地总面积的0.37%;林地、湿地、耕地和人工表面的面积均有所增加;其他类用地面积有所减少。②全区土地综合动态度均小于0.1%,土地利用/覆被变幅较小,除人工表面较活跃外,其他各类型变化相对缓慢,且各省土地利用区域差异较小。③研究区内景观基质未发生改变,区域景观破碎度递减,景观多样性水平上升,景观聚集度和连续性微弱下降,景观整体保持较完整态势。退牧还草工程的实施使土地利用/覆被结构和景观格局均得以优化。

Land use/land cover change in the grassland restoration program areas in China, 2000-2010

Using the 3S (RS, GIS, GPS) technologies, quantitative analysis method of landscape patterns, and the 30 m resolution land use/land cover data, this study examines the spatiotemporal characteristics of land use/land cover change in the grassland restoration areas in China from 2000 to 2010. We apply two parameters land use transfer matrix and land use dynamic degree to explore the speed and regional differentiation of land use change. This study analyzes the characteristics of landscape patterns at the class and landscape levels in the study area and explores the ecological effect of land use pattern and regional ecological processes. The results show that: (1) Grassland, woodland, wetland, farmland, tificial surface, and others were the main landscape types in the study area in the past decade. The ecosystem structure was stable. About 0.37% of the total grassland area in 2000 experienced change in land use/land cover types. The area of woodlands, wetlands, farmlands, and tificial surface expanded. The area of "others" has declined. (2) The dynamic degree of regional land use was less than one percent in the recent ten years. The speed of land use and land cover change was low, and regional differentiation of change between the provinces was small. (3) The matrix of the landscape did not change in the study area. Landscape fragmentation index values decreased progressively; landscape diversity rose continuously; landscape aggregation and continuity decreased slightly; the landscape maintained relative integrity. The grassland restoration program implementation evidently improved the structure and stability of the land use / land cover.