基于遥感与GIS的民勤盆地荒漠垦殖研究

Study of desert reclamation in Minqin Basin Using Remote Sensing and GIS

通过对民勤盆地1959年航片,1973年MSS影像,1987、1994、1998和2001年TM影像的人机交互目视解译结合自动分类,制作了6个典型年代的绿洲分布图。利用GIS软件进行迭加运算处理并进行面积统计,获得民勤盆地40年来荒漠垦殖位置变化图和面积变化数据。结果表明,40年来民勤盆地荒漠垦殖发展迅速,其中尤以70年代和90年代增加显著;荒漠垦殖范围扩展的方式主要有两种:一种是原有绿洲的"摊饼式"扩展,一种是向荒漠腹地的"跳跃式"推进;荒漠垦殖扩展的原因,早期主要受"以粮为纲"政策的影响,晚期在于绿洲生态环境的恶化和经济利益的驱动。荒漠垦殖的迅猛发展极大地破坏绿洲外围的生态环境,加速了荒漠化进程。

The oasis distribution maps of six typical years were made using aerial photo in 1959, MSS image in 1973 and TM images in 1987, 1994, 1998, 2001 by combining visual interpretation and automatic classification method. The distribution and area change data of desert reclamation in Minqin Basin during last 40 years were obtained by overlay analysis and area statistic in GIS. The result indicates the desert reclamation in Minqin Basin developed rapidly, especially in 1970s and 1990s. The two extending modes of desert reclamation are the extend of oasis 'Pizza' and extend to the desert hinterland jumpily. The extending of desert reclamation is attributed to the early policy of 'The most importance thing is commissariat' and lately entironment deterioration of oasis and derive of economic benefit. The rapid development of desert reclamation have badly damaged the periphery entironment of oasis and accelerated the desertification.