影响祁连山区域地貌-水文系统各地理要素的主成分分析

祁连山区域地貌复杂，从而引起水文系统以及生态系统的复杂性。水文系统是引起生态系统复杂的重要原因之一。对影响祁连山区域地貌——水文系统的9个重要地理要素：即流域盆地的总高度、流域的海拔高度、流域周长、河道总长度、河道总数、平均分叉率、河谷最大坡度(度)、河源数以及流域面积进行了综合分析，将其归为3类，即流域盆地的规模，流域侵蚀状况和流域河系形态。在此基础上，认为若要在以后对影响祁连山区域地貌——水文系统地理要素进行分析时，可以直接选取流域面积，流域盆地出口的海拔高度和河道分叉率作为3类地理要素的代表，进行区域地貌——水文系统分析，从而能够降低分析问题的疑难程度与复杂性。

Principal component analysis of geological factors related to landforms-hydrological system of Qilian mountain region

Landforms in Qilian Mountain is very complex.This leads to the complex of hydrological system and ecological system.Hydrological system is one of the major reason that caused the complex of ecological system.Nine major geological factors,the total altitude of water catchment,elevation of water catchment,circumference of water catchment,the total length of the river course,the total number of the river course,the average branch rate of the river course,the maximum slope of river valley,the number of source of the river and the area of the water catchment,were analyzed in this paper.We consider that these nine geological factors were divided into three types,namely the scale of water catchment,the situation of water catchment erosion and river system formation.Based on this,if one do some analysis about the factors that effect the landforms hydrological of Qilian mountain,they may elect directly the area of water catchment,elevation altitude of the outlet of the water catchment and the branch rate of river course and research on the landforms hydrological system of Qilian mountain.Therefore,the difficulties and complexity in dealing with some problem will be decreased.This result has some practical significance.