Wang Qi, Yu Shi, Jiang Ping-Ping, Sun Ping-An
Guangxi Key Laboratory of Environmental Pollution Control Theory and Technology, College of Environmental Science and Engineering, Guilin University of Technology, Guilin 541004, China.
Key Laboratory of Karst Dynamics, Ministry of Natural Resources/Guangxi, Institute of Karst Geology, Chinese Academy of Geological Science, Guilin 541004, China.
Huan Jing Ke Xue. 2021 Oct 8;42(10):4687-4697. doi: 10.13227/j.hjkx.202012040.
To explore the influence of human activities on the Yangtze River water chemistry, water samples were obtained from a representative section the main river stem/branch in wet and normal seasons in 2016. Ion ratio analysis, principal component analysis(PCA), and chemical ion balance calculations were performed, and carbonate rock dissolution rates were determined based on carbonate and exogenous acids. The result show that HCO-Ca is the dominant hydrochemistry type, indicating that the dissolution of carbonate rocks in the basin is the main process affecting hydrochemistry, and carbonate acid is significant in the weathering of carbonate rocks. In addition, the proportion of carbonate acid dissolution in the wet and normal seasons accounted for 60.33% and 59.14% of the total dissolution, respectively. The dissolution ratio among the different sampling points was notable, which indicates that the carbon sink effect of exogenous acid cannot be ignored. In addition, cation exchange some influence on hydrochemistry but was not the main reaction process. Compared with hydrological monitoring data for the last few years, the weathering of rocks by sulfuric and nitrate acids has strengthened, and the negative effects of anthropogenic pollution in the Yangtze River have increased.
为探究人类活动对长江水化学的影响，于2016年在长江干流/支流的一个代表性断面采集了丰水期和正常水期的水样。进行了离子比值分析、主成分分析（PCA）以及化学离子平衡计算，并基于碳酸盐和外源酸测定了碳酸盐岩溶解速率。结果表明，HCO-Ca是主要的水化学类型，这表明流域内碳酸盐岩的溶解是影响水化学的主要过程，碳酸在碳酸盐岩风化中作用显著。此外，碳酸溶解在丰水期和正常水期分别占总溶解量的60.33%和59.14%。不同采样点间的溶解比例存在显著差异，这表明外源酸的碳汇效应不容忽视。另外，阳离子交换对水化学有一定影响，但并非主要反应过程。与过去几年的水文监测数据相比，硫酸和硝酸对岩石的风化作用增强，长江流域人为污染的负面影响增大。
