甘南牧区土地利用结构的时空变化研究

以甘南牧区2001—2009年的土地利用变更数据为基础，采用数量分析的方法对全区土地利用结构的时空变化规律进行研究。结果表明:全区主要用地类型为牧草地和林地，分别占总面积的67.30%和24.68%。牧草地、未利用地、交通运输用地、水域在各县（市）的分布比较均匀，而园地、水利设施用地、其他农用地、耕地在各县（市）的分布不均匀。全区耕地、其他农用地呈减少趋势，牧草地和林地呈增加趋势；耕地强度指数的绝对值最大，水利设施用地动态度的绝对值最大，分别为0.497 6%和45.570 5%。耕地、牧草地、林地变化贡献率最为显著，分别为0.481 2，0.323 9，0.143 1。空间上临潭县、合作市、迭部县对全区土地利用结构变化的贡献较大。研究表明，退耕还林还草政策在甘南牧区得到了较好落实，取得了显著成效。随着投资力度加大，甘南牧区的水利设施用地、交通运输用地、居民点及工矿用地面积增加较大。

Research for Spatiotemporal Changes of Land Use Structure in Pastoral Area of Gannan

The spatiotemporal changes of land use structure in pastoral area of Gannan was studied with the method of quantitative analysis based on the changing land use structure data of Gannan Tibetan prefecture from 2001 to 2009. Results showed that grassland and woodland were the main lands in Gannan, accounting for 67.30% and 24.68% of the total area, respectively. Grassland, unused land, traffic land and water body in the counties or cities distributed evenly, while the garden, water conservancy facilities, the other agricultural land and cultivated land distributed unevenly. The other agricultural land and cultivated land in the entire prefecture showed a decreasing trend, grassland and woodland tend to increase, absolute value of intensity index of cultivated land was the largest, absolute value of dynamic degree of water conservancy facilities was the largest, which were 0.497 6% and 45.570 5%, respectively. The change contribution rates of cultivated land, grassland and woodland were more significant, which were 0.481 2, 0.323 9 and 0.143 1, respectively. With respect to the spatial scale, Lintan, Hezuo and Diebu had made great contributions to land use change in Gannan Tibetan Prefecture. The study showed that the policy of returning farmland to forestland and grassland in pastoral area of Gannan was well implemented and had made the remarkable achievements. With the investment being increased, water conservancy facilities, traffic land, land for residential areas and mining have developed rapidly.