Abstract: The changes of river system in the Arid Area are major aspects of env ironmental evolvement and are related to other aspects closely. To research the process of rivers system changes is the first step to study the environmental evolvement of the Arid Area. The watercourse location of Santun River and Hutubi River was reconstructed in different historical periods by re-analysis on historic al materials, historical maps, historical files, being combined with the modern scientific achievements on climatology, hydrology and remote sensing images. The main results are (1) Santun River and Hutubi River belonged to one river system, which was one of inpouring rivers to Manas Lake before 20^thcentury; (2) Santun River and Hutubi River were apart in the first 20 years of 20^thcentury due to the reduction of the two rivers' current and the change of the rivers' courses; (3) all courses of Santun River and Hutubi River were fixed by Human being in the last 50 years; (4) precipitation changes in the north slope of Tianshan Mountain play the main role in the river system changes of Santun River and Hutubi River in the end of 19^thcentury and at the beginning of 20^thcentury; (5) human activiy is the main cause of the river system changes of Santun River and Hutubi River in the last 50 years.

Key words: Manas Lake, Santun River, Hutubi River, river system changes

摘要： 利用历史文献记载、历史地图、大比例尺地形图、各类地理考察成果、卫星影像资料，结合实地考察，采用历史地理学溯源法、地名学分析法、历史文献和历史地图解读等方法，对一直未引起学术界足够重视的天山北坡三屯河与呼图壁河水系的历史变迁问题进行了深入的论证研究，提出了近300年来玛纳斯湖群的历史变迁与三屯河、呼图壁河水系的历史变迁密切相关，复原了近300年来三屯河与呼图壁河水系河道变迁、水流空间分布过程及其与玛纳斯湖群历史变迁的密切关系，并且结合新疆近350年来的气候变化与人类社会经济活动变化的特点，分析了不同时间阶段河流水系变迁的主导因素。

关键词: 玛纳斯湖, 三屯河, 呼图壁河, 河道变迁