Chai et al. (2025) A novel index for evaluating the salinity control effectiveness of winter and spring irrigation during soil freezing−thawing process

Identification

• Journal: Soil and Tillage Research
• Year: 2025
• Date: 2025-10-11
• Authors: Mingtang Chai, Xin Li, Ruomei Wang, Wangcheng Li
• DOI: 10.1016/j.still.2025.106910

Research Groups

• School of Civil and Hydraulic Engineering, Ningxia University, China
• Key Laboratory of the Internet of Water and Digital Water Governance of the Yellow River, Ningxia University, China

Short Summary

This study developed and validated a coupled water-heat-salt model to quantitatively evaluate the salinity control effectiveness of winter and spring irrigation during soil freezing-thawing cycles. It introduced a novel Salt-Time Index (STI) and found that winter and spring irrigation have complementary effects, with winter irrigation providing longer-lasting suppression and spring irrigation achieving deeper desalination.

Objective

• To quantitatively evaluate the salinity control effectiveness of winter and spring irrigation during soil freezing-thawing processes, considering factors such as irrigation volume, groundwater level, and soil texture.
• To develop a novel index (Salt-Time Index, STI) for precisely assessing salt-control effectiveness, overcoming limitations of single concentration metrics.

Study Configuration

• Spatial Scale: Soil profile scale, considering various soil textures (sandy loam, loam).
• Temporal Scale: Seasonal, focusing on freezing-thawing cycles and the duration of irrigation effectiveness (winter and spring periods).

Methodology and Data

• Models used: A coupled water-heat-salt model, incorporating phase change processes and groundwater level fluctuations.
• Data sources: Field monitoring data for model validation.

Main Results

• The developed coupled water-heat-salt model accurately described salt transport patterns during freezing-thawing cycles, incorporating phase change processes and groundwater level fluctuations.
• The novel Salt-Time Index (STI) revealed complementary salinity control effects of winter and spring irrigation:
  • Winter irrigation (300 mm) provided 2.9 times longer-lasting salinity suppression compared to spring irrigation.
  • Spring irrigation achieved 2.5 times deeper desalination compared to winter irrigation.
• Lowering the groundwater level from -0.5 meters to -2.0 meters below the surface significantly enhanced salt control across all soil types.
• Sandy loam and loam soils exhibited optimal salt control performance with irrigation volumes ranging from 150 mm to 225 mm.

Contributions

• Development of the novel Salt-Time Index (STI), which provides a more precise and comprehensive evaluation of salinity control effectiveness compared to traditional single concentration metrics.
• Quantitative analysis of the complementary effects of winter and spring irrigation on salinity control, offering insights into their respective strengths in terms of duration and depth of desalination.
• Identification of the significant role of groundwater level and optimal irrigation volumes for different soil textures in enhancing salt control during freezing-thawing cycles.
• Provides scientific guidance for optimizing irrigation strategies, improving water resource utilization, and regulating soil salinization for sustainable agricultural development.

Funding

• Not available in the provided text.

Citation

@article{Chai2025novel,
  author = {Chai, Mingtang and Li, Xin and Wang, Ruomei and Li, Wangcheng},
  title = {A novel index for evaluating the salinity control effectiveness of winter and spring irrigation during soil freezing−thawing process},
  journal = {Soil and Tillage Research},
  year = {2025},
  doi = {10.1016/j.still.2025.106910},
  url = {https://doi.org/10.1016/j.still.2025.106910}
}