遥感与GIS支持下的榆林地区土地利用动态变化研究

Using Remote Sensing and GIS to Analyse Land Use Dynamic Change in Yunlin, Shaanxi

利用 1986、1996和 2 0 0 0年人机交互解译的遥感影像资料 ,采用GIS空间分析技术 ,通过叠加 3个不同时期的土地利用图 ,分析了榆林地区 1986～ 2 0 0 0年期间土地利用时空变化特征 ,同时还分析了榆林地区 14年间沙地逆转恢复的情况。结果表明 :1986～ 1996年期间土地利用变化主要表现为 :沙地减少了 2 2 .2 5 % ,草地、林地和城乡居住建设用地分别增加了 6 .5 1%、4 .6 3%和 3.5 5 %。 1996～ 2 0 0 0期间 ,沼泽地、盐碱地分别减少了 2 6 .11%、2 4 .39% ,沙地仅减少 0 .79% ,草地减少了 2 .86 % ,林地仅增加了 0 .17% ,而旱地增加了 3.2 8%。城乡居住建设用地增加了14 .13%。 14年间沙地面积减少了 12 86 84 .17hm2 ,沙地净逆转为草地 118872 .99h2 、旱地 36 0 5 .0 7hm2 、林地 4 0 4 9.5 2hm2 。

The Yulin Prefecture of Shaanxi Province is located at north-western China and on the transitional area of the Mu Us desert and the Loess Plateau. After the founding of the People′s Republic of China, tremendous efforts have been made into the rehabilitation of decertified land and result the change of turning land from the desert has been achieved in the area. Based on the topographic map, remote sensing images in 1986、1996 and 2000, using GIS Spatial analysis techniques, land use change maps were made on Yilin, Shaanxi. Land use change maps indicated desertified land have decreased by 22.25% whereas grassland and woodland increased by 6.51% and 4.63% respectively between 1986～1996.This tendency is attributed to measures of sandy rehabilitation. The results indicated that between 1996～2000, there were 0.41%、 26.11% and 24.39% decline in desertified land、swampland and salt and 2.86% increase in grassland. Cultivated land shows an increase of 3.28% between 1996～2000.there was 0.17% increase in woodland. There was a net decrease of 128 684.17hm2 of decertified land, 3 065.07 hm2 of which was converted to cultivated land, the conversion of 4 049.5 hm2of decertified land to woodland, 1 212 945.51hm2 of decertified land to grassland.