Neyshabouri, Sepideh Zeraati , Khashei-Siuki, Abbas , Akbari, Mohammad Ghasem
2026-08-01 JOURNAL OF HYDROLOGIC ENGINEERING 2026 31(卷), 4(期), (null页)
While advanced models for groundwater level (GWL) forecasting have proliferated, their reliance on extensive auxiliary data and computationally intensive hyperparameter tuning limits real-world deployment, particularly in data-scarce arid regions. To bridge this, the present study introduces the synergistic autoregressive fuzzy-support vector machine (SAR-FSVM) framework for monthly GWL forecasting in the Birjand aquifer, Iran, and comparing its performance against conventional approaches, including multiple linear regression (MLR), support vector machine (SVM), and autoregressive SVM (AR-SVM). The proposed framework uniquely integrates three complementary components: the temporal dependency modeling of autoregressive (AR) models, the uncertainty quantification of fuzzy logic, and the nonlinear pattern recognition of SVMs within a single, end-to-end architecture that operates exclusively on historical GWL data. Using monthly data from 11 observation wells (1998-2017), the model was developed and validated. Results showed that SAR-FSVM outperforms conventional models, achieving a Nash-Sutcliffe efficiency coefficient (NSE) of 0.937 (training) and 0.907 (testing), a root-mean-square error (RMSE) of 0.228 m (training) and 0.267 m (testing), and a mean absolute error (MAE) of 0.166 m (training) and 0.190 m (testing). The fuzzy logic component effectively managed input variability, while SVM captured nonlinear dynamics. Analysis revealed that 1-3-month lags (p=3) were the most influential predictors, capturing the memory effect, where previous water levels influence current conditions, inherent in the Birjand aquifer's groundwater system. Overall, SAR-FSVM offers a data-efficient and accurate decision-support tool for sustainable groundwater management in an arid environment and holds strong potential for application to other hydrogeological systems worldwide.