2026-05-31 AGRICULTURAL WATER MANAGEMENT 2026 329(卷), null(期), (null页)
Intensive agriculture in arid and semi-arid Northwest China leads to severe nitrate leaching, posing a serious threat to groundwater quality and ecosystem health. To investigate its driving factors, we applied four machine learning algorithms-Support Vector Machine (SVM), Random Forest (RF), Extreme Gradient Boosting (XGBoost), and Convolutional Neural Network (CNN)-to a synthesis of 43 published studies from the region. Results revealed that vegetable systems (44.75 kg ha(-1) season(-1)) leached 67% more nitrate than field crop systems (26.76 kg ha(-1) season(-1)). Among the models, XGBoost achieved the best performance (R-2 >= 0.75). SHAP analysis further identified irrigation and nitrogen input as the primary drivers, while soil organic matter played a key modulating role, particularly in vegetable systems. Nitrate leaching increased significantly when irrigation rates exceeded 300 mm or when nitrogen inputs surpassed 200 kg ha(-1) for crops and 680 kg ha(-1) for vegetables. These findings provide an empirical, data-driven foundation for agroecological risk assessment and support the design of precision nitrogen management practices in water-limited farming systems.