Hydrochemical Characteristics and Quality Assessment of Groundwater under the Impact of Seawater Intrusion and Anthropogenic Activity in the Coastal Areas of Zhejiang and Fujian Provinces, China

作者：Tengfei Fu, Qi Chen, Zhenyan Wang, Chenzhe Li, Wenquan Liu, Yushan Fu, Guangquan Chen, Qiao Su, Xingyong Xu, Hongjun Yu · 发表于：Lithosphere · 年份：2022 · DOI：10.2113/2022/1394857 · 被引用次数：15 · 研究领域：Groundwater and Isotope Geochemistry、Water Quality and Pollution Assessment、Fluoride Effects and Removal

Abstract Coastal groundwater is an important resource in the developed region associated with human health and sustainable economic development. To identify the origins of salinity and evaluate the impact of water-rock interactions, seawater intrusion (SWI), and evaporation on groundwater in the coastal areas of Zhejiang and Fujian provinces, a comprehensive investigation was performed. Meanwhile, nitrate and fluoride indicators resulting from the anthropogenic activity and SWI were also considered. At last, the water quality index (WQI) of coastal groundwater was evaluated with geochemical and multivariate statistical methods. The results indicated that (1) the groundwater in coastal areas of Zhejiang and Fujian provinces has been affected by SWI to varying degrees. The analysis of selected ion ratios (Na+/Cl− and Br−/Cl−) and isotopic compositions showed that SWI is the predominant cause of increasing salinity in the groundwater of Zhejiang Province, while the cause is water-rock interactions (ion exchange and mineral weathering) in Fujian Province. The hydrochemical evolution path of groundwater in Zhejiang Province is Ca/Mg-HCO3 to Na-Cl, while a different pattern of Ca/Mg-HCO3 to Na (Mg/Ca)-Cl occurs in Fujian Province. However, the trend of SWI development in both provinces was freshening. (2) Nitrification, sewage infiltration, and SWI increased the NO3− content in groundwater. Some of the NO3− concentration in Fujian Province exceeds the standard, and the nitrogen pol...