陇东黄土高原土地利用、覆盖变化及驱动力分析

Analysis on land-use/coverage change process and its driving forces on Loess Pleteau of east Gansu

从土地利用和土地覆被的角度出发,利用RS和G IS技术,分析了20世纪最后15 a该区土地利用和土地覆被变化在数量、结构和类型上的特点,并进一步分析了该区土地利用/土地覆被变化的驱动力,得出以下结论:15 a间除建设用地和草地面积增加外,其他土地利用类型都呈现出不同程度减少。其中耕地减少了20 691hm2,主要转变为建设用地,且减少的耕地多为位置相对优越,产量较高的优质良田;林地减少了12 269 hm2,主要转变为草地、旱地和建设用地;草地的面积增加了33 488 hm2,主要源自于林地和耕地的变化;交通建设用地高速增长,15 a间增加了9 278.8 hm2。该区土地利用和土地覆被变化的驱动力主要为自然因素、人口压力、经济因素及宏观政策等。

By dint of RS and GIS technology, this paper analyzed the quantities, inner structure, types and spatial distribution features of land-use/coverage change （LUCC） on Loess Plateau of east Gansu in the last fifteen years in 20th century, and the driving forces of LUCC were discussed in＇detail. It was discovered that all types of land--use were decreased to some extent, except for the construction land and grassland. The cultivated land area was decreased by 20691hm^2, which was generally fertile land with high quality in plain location and was mainly changed into construction land; the woodland area was decreased by 12269. 1hm^2, which was mainly changed into grassland, farmland and construction land; the grassland area was increased by 33488 hm^2, which was mainly derive from the conversion of woodland and farmland; the construction land area was increased by 9278.8hm^2 in fifteen years. The main driving forces of LUCC on Loess Plateau of east Gansu were the natural factors, the economic development, the population pressure, the adjustment of macro policies, and so on.