关键词: 西安地区, 河谷侵蚀, 侵蚀量, 计算公式

Abstract: On the basis of investigation and measurement in field and history data of erosion of river valley,the total erosion amount of the Bahe river valley in Xi'an region was studied,and the calculative formula of erosion amount of symmetric and nonsymmetrical river valley was given.The results show that the five terraces and relating flood plains of the Bahe river represent the six erosive stages,and there are differences on the erosion amount of every stage.From old to new,the first and the third stage are more intensive in erosion than the other four stages.The erosion amount is about 6.5 km³ in the area of 57.3 km² nearby Lantian county,Shanxi province.The erosion amount produced by side erosion of river is more than that produced by vertical erosion.The formula for calculating the erosion amount of Bahe river valley is applicable for other river valleys.The study has considerable significance for calculating the total erosion amount and the erosion amount of every stage and further to find out the regularity of erosion intensity change.

Key words: Xi'an region, erosion of river valley, erosion amount, formula for calculating