摘要
石羊河流域下游自汉代以来逐渐沙漠化,生态环境退化。其自然因素主要有:地形特征构筑了封闭的内陆河流域;水蚀是内陆河流域沙漠化的开始,上游集流区为中、下游提供了丰富的沙源;水资源的减少使得中、下游大面积湖积沙沙漠化。人为因素主要有:农业开发是引起水资源减少的关键,巩固边塞是引起河西走廊农业开发和耕地面积扩大的主要原因;战争对石羊河流域生态退化的影响不可忽视。石羊河下游民勤县在自汉代以来沙漠化和生态环境退化的漫长历史过程中,人为因素不断增强。20世纪中期以来,尤其是1958年红崖山水库建成以来,沙漠化过程中的人为因素占据了主导地位。
The lower reaches of Shiyang River Basin has been threatened desertification and ecological degeneration from Han Dynasty.The natural factors of causing desertification are as follows:the closed drainage system is constructed by the landform;the water erosion is the origin for sandy desertification;the upper area has provided richen sand source for the middle and lower reaches;the decrease of water resources from upper reaches has caused the desertification in lower reaches areas.The artificial factors are as follows:the agricultural exploitation is the key role for decreasing water resources,and it is a key causation that agricultural area was expanded for consolidating frontier defense in Hexi Corridor;the influence of historical war on ecological degeneration of Shiyang River Basin should not be ignored.In lengthy course of desertification and ecological degeneration from Han Dynasty,the artificial factors are ceaselessly strengthened in Minqin county in Shiyang River Basin lower.Since In middle period of 20 centuries,especially the Hongyashan Reservoir has been build in 1958,the artificial factors in sandy desertification have inhabited the dominant status.
出处
《干旱区地理》
CSCD
北大核心
2005年第2期150-155,共6页
Arid Land Geography
基金
国家"十五"重点攻关项目(2002BA517A-09)资助
