GIS支持下我国干旱区草地资源动态分析

以遥感与GIS为支撑技术,以干燥度为干旱指标,并以此提取草地的动态变化,分析1995-2000年的中国干旱区草地动态变化状况.研究表明:草地面积减少5 49×104 km2,主要表现在低覆盖度草地面积的大量减少,草地资源的变化主要是转变成耕地,城镇占用,及草地类型间的转换,并且有不同程度的退化.草地的变化以变耕地为主,主要是受人口的压力;草地的退化在很大程度上是过度放牧、盲目开垦耕地所致,而草地资源为我国西部、北部主要资源,这种草地的退化将造成我国北方环境的恶化及资源的退化.草地的动态变化以自然与人为动力为主.草地面积的减少及覆盖度的降低对中国干旱区的生态环境质量及区域经济发展有一定的影响. 

Analysis of Grassland Resource Dynamics in China's Arid Region Supported by RS and GIS

The grassland dynamics in China's arid region from 1995 to 2000 are analyzed based on RS and GIS and with aridity as the indicator of drought.The results show that the total area of grasslands has decreased by 54 900 km+2,especially with a great reduction in the area of low-coverage grasslands.The grasslands have mainly been changed into farmlands,occupied by buildup,and changed to other types of grasslands,with different degrees of degradation.The driving forces of grassland dynamics are mainly natural and human activities.The main reason of grassland change into farmlands is population pressure and grassland degradation is mostly caused by over grazing and blind reclamation for farmlands.The grassland is the main resource in the west and the north and its degradation will lead to worsening of the environment and degradation of the resource in northern China.Moreover,the reduction of grassland area and decrease of grass coverage will affect the eco-environment in the arid region in China and restrict the regional economic development.