【摘要】 黄河源区生态环境极其脆弱 ,在自然因素和人为因素的共同作用下 ,近年来源区生态环境退化加剧 ,表现为土地沙漠化 ,草场退化和水土流失加剧等过程。在软硬件系统支持下应用 GIS和遥感技术 ,结合野外调查和室内分析 ,通过基于知识的多重判据复合分类实现多源信息的集成 ,得到黄河源区生态环境信息系统。结果表明源区自 1987年至 1996年 ,10年来 ,沙漠化土地面积扩大了约 4113km2 ,年均增加 45 7km2 。其中严重沙漠化土地增加770 km2 ,年均增加 85 .6 km2 ;强烈发展的沙漠化土地增加 393km2 ,年均增加 43.7km2 ,正在发展中的沙漠化土地增加142 0 km2 ,年均增加 15 7.8km2 ;潜在沙漠化土地增加 15 30 km2 ,年均增加 170 km2 ,土地沙漠化呈现正过程的加速发展。更多还原

【Abstract】 The eco environment is very fragile in headstream region of Yellow river in recent years, the eco environment of headstream region degrades very quickly unfluenced by natural factor together with human being factor,in which desertification is main aspect of environment changing in this region. The eco environmental informatiom system in headstream region of Yellow river is worked out supported by GIS and RS,as well as outdoor investigation and indoor analysis, based on knowledge the classification is worked out and multi source data is gathered.The result indicates that from 1987 to 1996, during this decade, the area of desertificated land extended about 4113km 2,in which the very severe desertificated land increased 770km 2,85.6km 2 annualy. The severe desertificated land increased 393km 2,43.7km 2 annually. The ongoing desertifcated land increased 1420 km 2,157.8 km 2 annually. The potential desertificated land increased 1530km 2,170km 2 annually. Thus it can been seen that desertification extended very quickly in this region. The eco environment degrades very quickly because not only the degradation of all ecological factors are interrelated and interact on each other, each ecological ractor is derived and stimulated during the course of interaction,but also irrational activities of human intensify increasingly.更多还原