Hanxiang Xiong , Yi Li , Ruihan Xiong , He Xiong , Jiayao Tan , Shilong Yang , Hanting Liu , Xiaoqing Song , Xu Guo
{"title":"Integrating aquifer vulnerability and explainable machine learning for spatial prediction of groundwater fluoride","authors":"Hanxiang Xiong , Yi Li , Ruihan Xiong , He Xiong , Jiayao Tan , Shilong Yang , Hanting Liu , Xiaoqing Song , Xu Guo","doi":"10.1016/j.gsd.2025.101517","DOIUrl":null,"url":null,"abstract":"<div><div>Groundwater fluoride (F<sup>−</sup>) contamination has serious risks to public health and environmental sustainability. This study enhances spatial prediction of fluoride concentration (SPFC) in the Ordos Basin, northwest China, by applying a Light Gradient Boosting Machine (LGBM) model integrated with SHapley Additive exPlanations (SHAP) analysis. A total of 26 hydrological, geological, environmental, climatic, hydro-chemical, and anthropogenic indicators were incorporated. Key findings reveal that high fluoride concentrations (>1 mg/L) cover approximately 17.48 % of the basin, while moderate (0.5–1 mg/L) and low (<0.5 mg/L) concentrations account for 39.05 % and 43.47 % of the area, respectively. The LGBM model demonstrated high predictive accuracy with R<sup>2</sup> values of 0.9180 for the training set and 0.7579 for the validation set, and RMSE values of 0.0582 and 0.0748, respectively. SHAP analysis identified significant contributors to F<sup>−</sup> contamination, including hydro-chemical indicators (CMSH: 9.09 %, SAR: 5.45 %, TDS: 5.97 %, Na<sup>+</sup>: 5.71 %, pH: 4.94, Ca<sup>2+</sup>: 4.68 % and CAI: 4.68 %), socio-economic factors (population density: 5.19 % and GDP: 5.19 %), topographic factors (elevation: 4.42 %, TWI: 7.53 % and proximity to rivers: 6.75 %) and NDVI (4.94 %). Finally, an innovative matrix-based sustainable groundwater management (SGWM) framework was developed, integrating SPFC, IAV and groundwater storage (GWS) to delineate seven distinct management zones. This comprehensive approach from SPFC to SGWM significantly enhances the predictive accuracy and practical applicability of groundwater management strategies, providing a robust tool for addressing F<sup>−</sup> contamination and supporting the achievement of global health and environmental sustainability goals under the sustainable development goals (SDGs).</div></div>","PeriodicalId":37879,"journal":{"name":"Groundwater for Sustainable Development","volume":"31 ","pages":"Article 101517"},"PeriodicalIF":4.9000,"publicationDate":"2025-09-24","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"0","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Groundwater for Sustainable Development","FirstCategoryId":"1085","ListUrlMain":"https://www.sciencedirect.com/science/article/pii/S2352801X25001146","RegionNum":0,"RegionCategory":null,"ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q2","JCRName":"ENGINEERING, ENVIRONMENTAL","Score":null,"Total":0}
引用次数: 0
Abstract
Groundwater fluoride (F−) contamination has serious risks to public health and environmental sustainability. This study enhances spatial prediction of fluoride concentration (SPFC) in the Ordos Basin, northwest China, by applying a Light Gradient Boosting Machine (LGBM) model integrated with SHapley Additive exPlanations (SHAP) analysis. A total of 26 hydrological, geological, environmental, climatic, hydro-chemical, and anthropogenic indicators were incorporated. Key findings reveal that high fluoride concentrations (>1 mg/L) cover approximately 17.48 % of the basin, while moderate (0.5–1 mg/L) and low (<0.5 mg/L) concentrations account for 39.05 % and 43.47 % of the area, respectively. The LGBM model demonstrated high predictive accuracy with R2 values of 0.9180 for the training set and 0.7579 for the validation set, and RMSE values of 0.0582 and 0.0748, respectively. SHAP analysis identified significant contributors to F− contamination, including hydro-chemical indicators (CMSH: 9.09 %, SAR: 5.45 %, TDS: 5.97 %, Na+: 5.71 %, pH: 4.94, Ca2+: 4.68 % and CAI: 4.68 %), socio-economic factors (population density: 5.19 % and GDP: 5.19 %), topographic factors (elevation: 4.42 %, TWI: 7.53 % and proximity to rivers: 6.75 %) and NDVI (4.94 %). Finally, an innovative matrix-based sustainable groundwater management (SGWM) framework was developed, integrating SPFC, IAV and groundwater storage (GWS) to delineate seven distinct management zones. This comprehensive approach from SPFC to SGWM significantly enhances the predictive accuracy and practical applicability of groundwater management strategies, providing a robust tool for addressing F− contamination and supporting the achievement of global health and environmental sustainability goals under the sustainable development goals (SDGs).
期刊介绍:
Groundwater for Sustainable Development is directed to different stakeholders and professionals, including government and non-governmental organizations, international funding agencies, universities, public water institutions, public health and other public/private sector professionals, and other relevant institutions. It is aimed at professionals, academics and students in the fields of disciplines such as: groundwater and its connection to surface hydrology and environment, soil sciences, engineering, ecology, microbiology, atmospheric sciences, analytical chemistry, hydro-engineering, water technology, environmental ethics, economics, public health, policy, as well as social sciences, legal disciplines, or any other area connected with water issues. The objectives of this journal are to facilitate: • The improvement of effective and sustainable management of water resources across the globe. • The improvement of human access to groundwater resources in adequate quantity and good quality. • The meeting of the increasing demand for drinking and irrigation water needed for food security to contribute to a social and economically sound human development. • The creation of a global inter- and multidisciplinary platform and forum to improve our understanding of groundwater resources and to advocate their effective and sustainable management and protection against contamination. • Interdisciplinary information exchange and to stimulate scientific research in the fields of groundwater related sciences and social and health sciences required to achieve the United Nations Millennium Development Goals for sustainable development.