Liu et al. (2026) Depth-dependent lag, persistence, and hydro-thermal coupling of soil moisture in a basin of Northern China

Identification

• Journal: Journal of Hydrology
• Year: 2026
• Date: 2026-08-08
• Authors: Quanshan Liu, Ningbo Cui, Shunsheng Zheng, Daozhi Gong, Zhihui Wang, Fei Chen
• DOI: 10.1016/j.jhydrol.2026.136178

Research Groups

• State Key Laboratory of Hydraulics and Mountain River Engineering & College of Water Resource and Hydropower, Sichuan University, China
• Xiamen University of Technology, China
• Institute of Environment and Sustainable Development in Agriculture, Chinese Academy of Agricultural Sciences, China

Short Summary

This study investigates the depth-dependent lag, persistence, and hydro-thermal coupling of soil moisture in a basin of Northern China using multi-site observations at five depths. The results show that SM persistence increases with depth, accompanied by stronger spatial heterogeneity.

Objective

• Investigate the temporal dynamics, vertical propagation, persistence, SM–ST coupling, and environmental controls of soil moisture at different depths

Study Configuration

• Spatial Scale: Basin scale (Shandian River Basin) in Northern China
• Temporal Scale: Non-frozen periods from 2019 to 2022

Methodology and Data

• Models used: Not specified
• Data sources: Multi-site observations at five depths (3, 5, 10, 20, and 50 cm)

Main Results

• SM persistence increases by 164 % from 14 d at 3 cm to 37 d at 50 cm
• Vertical coupling between adjacent layers weakens downward, with the median maximum correlation decreasing from 0.93 in shallow intervals (3–5 and 5–10 cm) to 0.76 in the 20–50 cm interval
• SM–ST coupling shows positive hydrothermal co-variation at deeper soil, while shallow soil shows weak evaporation-related decoupling

Contributions

• Provides profile-scale observational evidence for representing depth-dependent soil moisture memory, vertical transmission, and SM–ST coupling in hydrological and land-surface studies

Funding

• Not specified

Citation

@article{Liu2026Depthdependent,
  author = {Liu, Quanshan and Cui, Ningbo and Zheng, Shunsheng and Gong, Daozhi and Wang, Zhihui and Chen, Fei},
  title = {Depth-dependent lag, persistence, and hydro-thermal coupling of soil moisture in a basin of Northern China},
  journal = {Journal of Hydrology},
  year = {2026},
  doi = {10.1016/j.jhydrol.2026.136178},
  url = {https://doi.org/10.1016/j.jhydrol.2026.136178}
}