基于地形梯度的陕西省土地利用变化研究

笔者利用2000、2010年土地利用现状和DEM数据,基于地形位梯度指数、分布指数和土地利用程度综合指数等,探讨了陕西省土地利用分布变化的地形梯度特征。研究结果表明:陕西省土地利用现状以林地、耕地和草地为主,三者土地面积占区域总面积的95%以上;2000—2010年土地利用变化特征是耕地面积逐渐降低,大量耕地退耕为草地(3761.33 km~2)和林地(1198.61 km~2),而建设用地面积明显增加,主要源于对耕地(729.66 km~2)和草地(225.86 km~2)的侵占;土地利用类型在地形位梯度上的变化特征是随着地形位的增高,草地、耕地、园地、水域、建设用地和未利用土地的分布指数逐渐降低,而林地与之相反。土地利用程度显示,在地形位指数较低的区域土地利用程度较高,土地利用类型转换剧烈,而随着地形位指数增高土地利用程度随之降低。

Land Use Change in Shaanxi Based on Terrain Gradient

This paper took Shaanxi Province as the research object, discussed the terrain gradient characteristic of land use distribution change based on terrain gradient index, distribution index and land use degree comprehensive index and DEM data in 2000 and 2010. The results showed that the farmland, forestland and grassland were the main land use types in Shaanxi Province, which all together accounted for above 95% of the total area; the change characteristic during 2000 to 2010 was that the area of farmland decreased gradually, which mainly turned to grassland (3761.33 km2) and forestland (1198.61 km2), the area of construction land increased obviously, which mainly came from the embezzlement of farmland (729.66 km2) and grassland (225.86 km2); the distribution index of grassland, farmland, garden land, water area, construction land and unused land increased with the increase of terrain, while forestland showed an opposite trend. The index of land use degree was higher in the region of lower terrain index, and the land use conversion was frequent in this region, the index of land use degree decreased with the increase of terrain index.