三峡大学学报（自然科学版）2026，Vol.48Issue(1)：32-40,9.DOI:10.13393/j.cnki.issn.1672-948X.2026.01.005
三峡水库典型支流水化学变化特征及成因分析
Characteristics and Causes of Water Chemistry in Typical Tributaries of the Three Gorges Reservoir
摘要
Abstract
In order to explore the characteristics of hydrochemical changes in the tributaries of the Three Gorges Reservoir area and the influence of the backwater of the main stream on the hydrochemistry of the tributary reservoir bays,the reservoir bays of the three typical tributaries of the Three Gorges Reservoir were sampled and analyzed in April 2022.The results showed that the dominant anions and cations in the three tributaries were HCO3-and Ca2+.The average concentration of HCO3-was 155.50 mg·L-1,152.20 mg·L-1,and 171.50 mg·L-1,accounting for 67%,93%and 95%of the total anion content respectively.The mean concentrations of Ca2+were 34.70 mg·L-1,49.40 mg·L-1,and 47.00 mg·L-1,accounting for 58%,61%and 60%of the total cationic content respectively.The hydrochemical type of Xiaojiang and Xiangxi River reservoir bays was HCO3--Ca2+,while the hydrochemical type of Daning River reservoir bays was HCO3-·SO42--Ca2+.The results of Gibbs diagram and end member diagram showed that the dissolution of carbonate rocks dominated by rock weathering was the main mechanism controlling water chemistry.Since the intensity of evaporate of salt rocks in the Daning River basin was higher than those of Xiaojiang and Xiangxi river,and there existed a scenic spot of small Three Gorges in Daning River with significant disturbance of human activities,the concentration of Cl-(26.60 mg·L-1)was 9～12 times higher than that in the reservoir bays of Xiaojiang(2.90 mg·L-1)and Xiangxi River(2.00 mg·L-1).By the conservative ion(such as Cl-and Na+)tracer method,the contribution rates in the backwater area of the three tributaries of Xiaojiang,Daning River and Xiangxi River were about 49.0%,70.5%and 71.9%,respectively.The influence of the main stream backwater on the reservoir bay of the three tributaries was related to the distance from the Three Gorges Dam and the flow of the tributaries,and the recharge and dilution degree of the tributary reservoir bay depended on the material difference and the size of the water mass from the main and tributaries.关键词
三峡水库/离子浓度/离子来源/贡献率/回水区Key words
Three Gorges Reservoir/ion concentration/ion source/contribution rate/backwater area分类
资源环境引用本文复制引用
杨紫剑,刘佳,肖尚斌,朱良辰,陈敏,康满春,李世剑,高婷..三峡水库典型支流水化学变化特征及成因分析[J].三峡大学学报（自然科学版）,2026,48(1):32-40,9.基金项目
国家自然科学基金项目(52130903) （52130903）
