甘肃河西走廊西大河中游湿地成因与保护对策研究

干旱的河西走廊永昌县境内分布有弥足珍贵的刘克庄、焦家庄、北海子、圣容寺等4块面积达20.38 km²的湿地，均分布于西大河中游的永昌盆地。湿地的形成是地貌-构造所控制的水文地质条件及地表水、地下水（泉水）相互转化共同作用的结果。受20世纪以来气候变暖趋势及人类过度开发利用水资源的影响，西大河中游湿地面积呈逐步减少的萎缩状态，目前较大的泉眼仅有879个，近30年来湿地面积减少40%以上。加强西大河上游祁连山径流形成区和水资源涵养区的生态环境保护，减少出山地表水的引用量，控制中游地下水开采量及地下水位，是保护有限湿地资源的主要对策措施。

Causes and protective strategy of wetlands in the middle reaches of the Xida River in Hexi Corridor,Gansu Province

In arid regions,such as Hexi Corridor in Gansu Province,Northwest China,wetland is rare and valuable especially.There are four wetlands in the middle reaches of the Xida River in Yongchang County of the corridor,i.e.,Liukezhuang,Jiaojiazhuang,Beihaizi and Shengrongsi,with an total area of 20.38 km2.Formation of the wetlands results from hydrogeological conditions,which are controlled by landform-structure,and intertransformation and interaction of surface water and groundwater (spring water).Since the 20th century,wetland area has been gradually reducing and shrinking in the middle reaches with climate warming and the overuse of water resources.The main counter measures to protect the limited wetland resources of this area are to reinforce the ecological environment protection in runoff formation and water conservation areas in the upper reaches of the Xida River and to reduce the use of surface water and exploitation groundwater in the middle reaches.