Explainable machine learning with ensemble-based uncertainty quantification for groundwater quality indices in the Ganfu Plain, China
摘要
Groundwater quality assessment is essential for sustainable water resource management, particularly in regions experiencing intensive anthropogenic pressures. In this study, we developed a data-driven framework that integrates groundwater quality indices, PSO-optimized XGBoost modeling, SHAP-based interpretability, and ensemble-based quantile uncertainty quantification. This framework enables simultaneous prediction, interpretation, and rigorous uncertainty analysis, and was applied to the Ganfu Plain, China, to predict both the water quality index (WQI) and entropy-weighted water quality index (EWQI) using hydrochemical and spatial parameters. The models achieved strong predictive performance, with nested cross-validation yielding low RMSE values across most folds. SHAP analysis consistently identified Mn, NO