Fu Tengfei, Li Chenzhe, Wang Zhenyan, Qi Chen, Chen Guangquan, Fu Yushan, Su Qiao, Xu Xingyong, Liu Wenquan, Yu Hongjun
Key Laboratory of Coastal Science and Integrated Management, First Institute of Oceanography, Ministry of Natural Resources of the People's Republic of China, Qingdao 266061, China; Laboratory for Marine Geology, Qingdao National Laboratory for Marine Science and Technology, Qingdao 266061, China.
MOE Key Laboratory of Groundwater Circulation and Environment Evolution and School of Water Resources and Environment, China University of Geosciences (Beijing), Beijing 100083, China; State Key Laboratory of Biogeology and Environmental Geology, China University of Geosciences (Beijing), Beijing 100083, China.
Mar Pollut Bull. 2023 Mar;188:114564. doi: 10.1016/j.marpolbul.2022.114564. Epub 2023 Feb 2.
Groundwater is a main source of water supply in Guangxi Province, China. The urbanization expansion and ocean dynamic may change the groundwater quality, which is an important issue due to its effects on human health. In this paper, the influence of seawater intrusion and anthropogenic activity on the Guangxi coastal aquatic environment was assessed by geochemical and multivariate statistical methods. The result indicated that the chemical composition of groundwater in the study area is obviously associated with seawater and the main groundwater types were Ca·Na-Cl, Ca·Na-HCO, and Ca-HCO·Cl The groundwater evolution path from land to sea in Guangxi is Ca-HCO3 → Na·Mg-Cl. The origin of salts in the study area is mainly controlled by mineral weathering, the hydrogen and oxygen isotopes contents point to the aqueous source of atmospheric precipitation. According to the results of PCA, seawater intrusion and pollution caused by human activities play an increasingly important role in the evolution of groundwater characteristics. Seawater intrusion is the main factor for the increase of groundwater salinity in Guangxi, while domestic sewage, industrial waste, fertilizers, and pesticides may contribute to the nitrate pollution of groundwater, especially in Beihai. The degree of groundwater nitrate pollution is as follows: Fangchenggang < Qinzhou < Beihai, which is associated with the degree of urbanization in the coastal area. Finally, the results of the water quality index (WQI) assessment show that 82.8 % of the samples were classified as excellent, while there is still a need to be vigilant about groundwater pollution caused by seawater intrusion and groundwater pollution. The results will be valuable for sustainable groundwater resource management in Guangxi coastal zone.
地下水是中国广西省的主要供水水源。城市化扩张和海洋动力可能会改变地下水水质，由于其对人类健康的影响，这是一个重要问题。本文采用地球化学和多元统计方法评估了海水入侵和人为活动对广西沿海水环境的影响。结果表明，研究区地下水的化学成分与海水明显相关，主要地下水类型为Ca·Na-Cl、Ca·Na-HCO和Ca-HCO·Cl。广西从陆地到海洋的地下水演化路径为Ca-HCO3→Na·Mg-Cl。研究区盐分的来源主要受矿物风化控制，氢氧同位素含量表明其水源为大气降水。根据主成分分析结果，海水入侵和人类活动造成的污染在地下水特征演化中发挥着越来越重要的作用。海水入侵是广西地下水盐度增加的主要因素，而生活污水、工业废物、化肥和农药可能导致地下水硝酸盐污染，尤其是在北海。地下水硝酸盐污染程度如下：防城港<钦州<北海，这与沿海地区的城市化程度有关。最后，水质指数（WQI）评估结果表明，82.8%的样本被评为优良，但仍需警惕海水入侵导致的地下水污染和地下水污染。研究结果将对广西沿海地区可持续地下水资源管理具有重要价值。
