内蒙古西部库布齐沙漠北缘沙漠化特征讨论

Discussion of Desertification on Northern Margin of the Hobq Desert,Western Inner Mongolia

磴口—乌拉特前旗一带,库布齐沙漠北缘前锋带被黄河严格地限制在河道南岸,即向北弧形突出的河道基本上是库布齐沙漠西段的北部边界。库布齐沙漠自19 ka前开始发育,7 ka以来在出现了横贯东西的沙漠覆盖之后,其北缘一直在向北扩展。作者通过历史文献记录、遥感影像解译,结合沉积特征与地貌演变等相关资料的分析,认为库布齐沙漠北缘由南向北不断前行,迫使磴口—乌拉特前旗段最初近东西向延伸的黄河河道向北弧形突出,并导致库布齐沙漠北缘前锋带被严格地限制在黄河南岸展布。库布齐沙漠北缘的持续向北推进,将对位于黄河北岸的河套盆地内大片湿地及农田生态环境安全产生严重的威胁。

The northern margin of Hobq Desert is strictly limited to the south of the Yellow River and the river in arc north basically is the northern border of the west section of Hobq Desert. Hobq Desert developing east—west19 ka ago has always been extending northward since 7 ka ago. By analyzing data such as historical document,remote sensing image and geomorphic sedimentary etc.,this paper holds that the desert from south to north led to the change of Yellow River from extension east—west to bulge in an arc,and caused the situation that Hobq Desert is strictly limited to the south of the Yellow River. Hobq Desert＇s northwest expansion will have a serious threat to the ecological environment safety of wetland to the north of Yellow River in Hetao basin.