遥感与GIS支持下的中国草地动态变化分析

ANALYSIS OF GRASSLAND DYNAMIC IN CHINA BASED ON RS AND GIS

运用GIS和RS技术 ,以LANDSATTM为数据源 ,监测我国草地资源近 5a来的变化 ,并对变化进行分析。研究表明 ,我国草地面积总量增加约 1 3 2× 1 0 4hm2 ,其中高覆盖度与中覆盖度草地面积增多 ,但低覆盖度草地面积减少。我国西部的草地面积减少 ,山西 ,内蒙古 ,吉林 ,陕西 ,甘肃 ,青海 ,宁夏 ,新疆均有不同程度的减少。其中内蒙古 ,新疆的各类草地变化显著。草地的变化有明显的东西部差异 ,西部的各类草地变化程度比东部剧烈。草地的变化受人类活动影响大 ,主要向耕地 ,城镇转化 ,同时草地存在严重的退化 ,随覆盖度的降低而增加 ,以西部地区为重。

By using TM datum based RS and GIS technology, the dynamic of china grassland from 1995 to 2000 is monitored. The results indicate that the amount of grassland area is increasing about 13.2×10 4 hm 2 from 1995 to 2000, with the high and middle cover grassland area increasing and that of low cover grassland decreasing. In the provinces of Western China, such as Shanxi, Qinghai, Gansu provinces etc, especially Inner Mongolia Autonomous Region and Xinjiang Uygur Autonomous Region, the area of grassland is decreasing. There exists significant difference between west China and east China in terms of grassland change, that is, the change degree of grassland in west China is greater than that of in east China. With regard to main driving forces, human activities have great impact on grassland change. As most of grassland has been shifted to farmland and urban, it shows economy gap between west China and east China. Meanwhile, there is serious degradation of grassland, especially in west China.