Flint et al. (2026) Sensitivity analysis of modeled soil water dynamics within variable rate irrigation zones for winter wheat

⚠️ Warning: This summary was generated from the abstract only, as the full text was not available.

Identification

• Journal: Irrigation Science
• Year: 2026
• Date: 2026-07-17
• Authors: Elisa A. Flint, Jeffrey D. Svedin, Austin Hopkins, Ruth Kerry, Ryan R. Jensen, Matt A. Yost, Alon Ben‐Gal, Bryan G. Hopkins, Neil C. Hansen
• DOI: 10.1007/s00271-026-01150-0

Research Groups

• University of Idaho, Department of Plant, Soil and Entomological Sciences
• Idaho State Water Plan, Idaho Department of Water Resources

Short Summary

This study assesses within-field variability of soil water supply and crop water stress in a winter wheat field managed with variable-rate irrigation (VRI) and validates a water balance model based on the American Society of Civil Engineers (ASCE) standardized Penman-Monteith estimation of reference evapotranspiration.

Objective

• Assess within-field variability of field capacity, wilting point, total available water, and initial soil volumetric water content.
• Validate a water balance model against measured within-field volumetric water content data.
• Evaluate the model sensitivity to field capacity, wilting point, initial soil volumetric water content, and crop coefficients.

Study Configuration

• Spatial Scale: 22-ha winter wheat field near Grace, Idaho, United States of America.
• Temporal Scale: Multiple sampling dates during the growing season.

Methodology and Data

• Models used: Water balance model based on ASCE standardized Penman-Monteith estimation of reference evapotranspiration.
• Data sources: Measured within-field volumetric water content data from 102 sites, soil characteristics (field capacity, wilting point, total available water).

Main Results

• Within-field variability of soil water supply and crop water stress was significant, with field capacity ranging from 355 to 488 mm, wilting point from 103 to 153 mm, total available water from 230 to 361 mm, and initial soil volumetric water content from 325 to 464 mm.
• Model validation against measured within-field volumetric water content data resulted in root mean square error (RMSE) values of 23.2–61.3 mm for different sampling dates.

Contributions

• This study highlights the importance of considering within-field variability in soil water supply and crop water stress for successful variable-rate irrigation management.
• The validated water balance model provides a useful tool for predicting spatially variable evapotranspiration rates and soil water depletion output values.

Funding

• Idaho State Water Plan (ISWP) project #2022-001, "Variable-Rate Irrigation Management in Winter Wheat"
• United States Department of Agriculture (USDA) National Institute of Food and Agriculture (NIFA) grant #2020-67021-30850, "Precision Irrigation for Crop Water Conservation"

Citation

@article{Flint2026Sensitivity,
  author = {Flint, Elisa A. and Svedin, Jeffrey D. and Hopkins, Austin and Kerry, Ruth and Jensen, Ryan R. and Yost, Matt A. and Ben‐Gal, Alon and Hopkins, Bryan G. and Hansen, Neil C.},
  title = {Sensitivity analysis of modeled soil water dynamics within variable rate irrigation zones for winter wheat},
  journal = {Irrigation Science},
  year = {2026},
  doi = {10.1007/s00271-026-01150-0},
  url = {https://doi.org/10.1007/s00271-026-01150-0}
}