Gan et al. (2026) Spatially refined modeling for agricultural groundwater management in Northwestern China

Identification

• Journal: Agricultural Water Management
• Year: 2026
• Date: 2026-08-04
• Authors: Lin Gan, Litang Hu, Zhongjing Wang, Na Zhang, Guiyu Yang, Suyue Yu
• DOI: 10.1016/j.agwat.2026.110678

Research Groups

• College of Water Sciences, Beijing Normal University
• Engineering Research Center of Groundwater Pollution Control and Remediation of Ministry of Education
• School of Civil Engineering, Tsinghua University
• School of Civil and Hydraulic Engineering, Ningxia University
• Water Conservancy Research Institute of Ningxia Hui Autonomous Region
• State Key Laboratory of Watershed Water Cycle Simulation and Regulation

Short Summary

This study proposes a spatially refined coupled surface water-groundwater (SW-GW) flow model to capture the spatiotemporal dynamics of groundwater response to surface irrigation at the farm-grid scale in the Qingtongxia Irrigation District. The model outperformed a coarse-resolution model in groundwater level simulation, reducing RMSE by 0.37 m during calibration and 0.24 m during validation.

Objective

• To develop a high-resolution SW-GW coupled model using high-quality water diversion data to capture the spatiotemporal dynamics of groundwater response to surface irrigation at the farm-grid scale in the irrigation district.
• To evaluate the performance of the coupled model through a multi-scale validation framework, including temporal and spatial comparisons of field water consumption between remote sensing and hydrological modeling in the main and branch canals.

Study Configuration

• Spatial Scale: 30 m × 30 m uniform grid with 5998,640 cells in a single layer.
• Temporal Scale: Simulation period spans from January 1, 2019, to December 31, 2022, partitioned into 144 time intervals of 10 days each.

Methodology and Data

• Models used: Nested-Grid based Groundwater Modeling Software (NGGMS).
• Data sources: High-quality water diversion data from 2019 to 2022, compiled from field surveys and data organization.
• Canal leakage recharge and irrigation infiltration recharge calculated using Eqs. (1) and (2), respectively.

Main Results

• The spatially refined model outperformed a coarse-resolution model in groundwater level simulation, reducing RMSE by 0.37 m during calibration and 0.24 m during validation.
• Groundwater levels rose in over-exploited areas from 2019 to 2022, while depths exhibited an upward trend in shallow groundwater zones.
• The proportion of areas with depths of 1.5–3.0 m expanded by 5.4%.
• Areas with groundwater depths below 2.2 m increased by 16.0% during summer-autumn irrigation.

Contributions

• This study provides a quantitative, high-resolution method for analyzing SW-GW interactions, supporting sustainable groundwater management and salinization control.
• The model's ability to capture local-scale groundwater dynamic processes is highlighted through an analysis of northern farmland at high salinization risk.

Funding

• This research was funded by the National Key Research and Development Program of China (Grant No. 2017YFC0406400).
• The authors acknowledge the support from the Beijing Natural Science Foundation (Grant No. L172011).

Citation

@article{Gan2026Spatially,
  author = {Gan, Lin and Hu, Litang and Wang, Zhongjing and Zhang, Na and Yang, Guiyu and Yu, Suyue},
  title = {Spatially refined modeling for agricultural groundwater management in Northwestern China},
  journal = {Agricultural Water Management},
  year = {2026},
  doi = {10.1016/j.agwat.2026.110678},
  url = {https://doi.org/10.1016/j.agwat.2026.110678}
}