干旱地区(包括半干旱地区)占世界陆地总面积的1/3。在我国,干旱地区约占全国总面积的1/4。随着我国工农业的发展,干旱地区的需水要求日益殷切。因此,对干旱地区水文特征的分析研究,对工、农、牧业及生活用水都具有重要的意义。

The Tian Shan is a famous mountain range in the arid region in China. Prom its southern and northern slopes, there flow many perennial rivers such as Hi He, manas He, maidu He, Weigan He, aksu He and so on.Total annual runoff volume amounts to 56,300 million m³.One of main features of runoff in the Tian Shan is that its vertical zonation being very prominent. The rivers are mainly fed by alpine glacial meltwater, which is also another main feature of runoff in the arid region in China.