西北干旱区水资源开发的水文效应及其利用模式的变化

我国西北干旱区主要分布在新疆、青海和甘肃及内蒙西部。这里气候干旱,水资源对干旱区的经济发展有着决定性意义,在干旱区“没有灌溉就没有农业”。水资源不仅影响到农牧业发展,同时也影响到工矿资源开发和城市的发展。水资源既是宝贵的自然资源,也是干旱区自然环境综合体中最活跃的因素之一。水资源开发利用已引起一系列水文效应和生态环境的变化,尤其是干旱区水资源开发中水循环各要素变化是很强烈的,因此研究干旱区的水资源开发的水文效应不仅具有理论意义,也有重要的实践意义。

HYDROLOGICAL EFFECT OF WATER RESOURCES DEVELOPMENT AND ITS CHANGES OF USED MODELS IN ARID ZONE OF NORTHWEST CHINA

Water resources are not only a valuable natural resources but also one of the most active environmental factors in the arid zone. Water resources brought about, in developing and using them, an important influence on socio-economic development in the arid zone. According to statistics, total amount of annual available water resources in the arid zone is 53,160 million m3, which is 51% of the total water resources of Northwest China. At present, annual available surface water is 49,300 million m3, which is 50.5% of the total surface runoff. Annual amount of groundwater exploitation is 3,850 million m3, which is 9.7% of total amount of groundwater recharge in the plain region of the arid zone.Due to large development of water resources after liberation, the increase in the use of water resources has produced numerous hydrological changes, such as changes of rivers runoff regimes, shortage of groundwater resources, dry up or salify of lake water. Furthermore, it has brought about change of used models and ecologic-environment.In order to use water resources reasonably, it is necessary to pay attention to unified planning of river basin, to sum. up experiences of water resources utilization in different regions and to set up optimum models in different types of water resources utilization. Some suggestions for rationally using and protecting water resources are presented in this paper.