关键词: 离子径流量, 离子总量, 离子径流模数, 侵蚀强度, 时空变化

Abstract: Erosion at the upper reaches of Changjiang River is intensive.It is of significance to study the chemical flow and the corrosion in this area for analysing the composition and the chemical characteristics of the suspended materials in the Changjiang River and the Chemical and physical processes in this river system.The annual average content of ions at the upper reaches of Changjiang (Yichang Station)is estimated to be 202.7mg/1. The discharge of ions is 2898.kg/s. The total amount of transported ions is 91.403 million tons, accounting for 61.7% of the total amount in the Changjiang River Basin and 26.5% of the total amount of transported ions in China. The intensity of corrosion can be reflected by the modulus of chemical flow. The average modulus of chemical flow at the upper reaches of Changjiang River is 90.9t/km²·a, which is higher than the country's average.The highest value occurs in the wujiang River Basin in the southern section of the studied area, which is 133t/km²·a. The smallest value, which is only 62t/km²·a, occurs in Jinshajiang River and yagongjiang River basins in the western part of the studied area.

Key words: chemical flow, corrosion, total amount of transported ions, modulus of chemical flow