Hydrochemical assessments and driving forces of water resources in coal mining areas: a case study of the Changhe River Basin, Shanxi

• Published in: Environmental earth sciences 2023-10, Vol.82 (19), p.447, Article 447
• Main Authors: Yan, Zixuan, Li, Zhanbin, Li, Peng, Zhao, Chenxu, Xu, Yaotao, Cui, Zhiwei, Sun, Hu
• Format: Article
• Language: English
• Subjects: Anion exchanging; Anions; Arid regions; Arid zones; Biogeosciences; Calcium ions; Carbonate rocks; Carbonates; Cation exchange; Cation exchanging; Cations; Coal; Coal mining; Correlation analysis; Dissolution; Dissolving; Earth and Environmental Science; Earth Sciences; Environmental Science and Engineering; Geochemistry; Geology; Groundwater; Groundwater mining; Hydrochemicals; Hydrology/Water Resources; Ion sources; Mining accidents & safety; Original Article; Qualitative analysis; Quality assessment; Quality control; River basins; Rivers; Semi arid areas; Semiarid lands; Semiarid zones; Silicates; Surface water; Surface-groundwater relations; Terrestrial Pollution; Water analysis; Water management; Water quality; Water quality assessments; Water resources; Water resources management; Water sampling; Water security; Weathering
• ISSN: 1866-6280; 1866-6299
• DOI: 10.1007/s12665-023-11146-0

Explore the hydrochemical characteristics of surface water (SW) and groundwater (GW) under coal mining activities and controlling factors is essential to ensure water security. This research concentrates on the Changhe River Basin (CRB). Water samples were collected from 27 sites within the CRB in May, July and December 2022. A qualitative analysis of hydrochemical characteristics and major ion sources was conducted based on Piper plots, Gibbs plots, Pearson correlation analysis and ion ratio methods. The PCA ~ RSR model was used to assess the current status of SW and GW quality in the CRB. We found that the hydrochemical type of SW and GW is HCO 3 –Ca, with HCO 3 − accounting for 62.2% ~ 87.9% of the total anions and Ca 2+ accounting for 27.4% ~ 31.3% of the total cations. Rock weathering is the main factor affecting the hydrochemical of CRB. SW is affected by the weathering and dissolution of both silicate and carbonate rocks, while GW is mainly affected by the weathering and dissolution of silicate. The cation exchange also has influence on GW. The cations in the water are mainly derived from rock weathering dissolution and exchange reactions, while SO 4 2− in anions is mainly imported from outside. The results of the water quality assessment showed that water quality in the midstream of the study area is poor and coal mining has seriously affected water safety issues. The study reveals the impact of coal mining on hydrochemical. It provides a scientific basis for the protection and management of water resources under coal mining activities in arid and semi-arid regions.