Yan et al. (2026) Projecting the changes in streamflow components based on the generalized proportionality hypothesis

Identification

• Journal: Journal of Hydrology
• Year: 2026
• Date: 2026-01-02
• Authors: Xin Yan, Qi Feng, Wei Liu, Xiaohua Wei, Meng Zhu, Lianmei Yang, Zhi Li
• DOI: 10.1016/j.jhydrol.2025.134902

Research Groups

• State Key Laboratory of Ecological Safety and Sustainable Development in Arid Lands, Northwest Institute of Eco-Environment and Resources, Chinese Academy of Sciences, Lanzhou, China
• State Key Laboratory of Soil Erosion and Dryland Farming on the Loess Plateau, College of Natural Resources and Environment, Northwest A&F University, Yangling, Shaanxi, China
• Department of Earth, Environmental and Geographic Sciences, University of British Columbia (Okanagan), Kelowna, Canada

Short Summary

This study developed a two-stage runoff model based on the generalized proportionality hypothesis to project the differential responses of surface runoff and baseflow to climate change across China's Loess Plateau. It found distinct sensitivities of these streamflow components to precipitation and evapotranspiration changes under future climate scenarios.

Objective

• To systematically project the differential responses of streamflow components (surface runoff and baseflow) to climate change across China's Loess Plateau.
• To develop a novel analytical framework (a two-stage runoff model based on the generalized proportionality hypothesis) for coupled streamflow component assessment.

Study Configuration

• Spatial Scale: 56 hydrological stations nested in 13 basins of China’s Loess Plateau.
• Temporal Scale: Projection period from 2021 to 2050.

Methodology and Data

• Models used: A two-stage runoff model developed in this study, based on the generalized proportionality hypothesis.
• Data sources:
  • Trend-preserving bias-corrected climate data from five regional climate models under RCP4.5 and RCP8.5 scenarios.
  • Observed data for model validation.

Main Results

• The developed model demonstrated satisfactory performance during validation, with R² values of 0.898 for surface runoff and 0.902 for baseflow when compared to observed data.
• Under the RCP4.5 scenario, increased precipitation (ranging from 0.57 meters per year to 4.63 meters per year) led to an increase in surface runoff at 95% of stations and an increase in baseflow at 80% of stations.
• Under the RCP8.5 scenario, enhanced evapotranspiration (ranging from 1.36 meters per year to 1.88 meters per year) significantly reduced baseflow at 30% of stations, a proportion notably higher than the 11% observed for surface runoff.
• This differential response is attributed to inherent hydrological characteristics: rapid surface runoff generation triggered by storm rainfall versus slower soil water-to-groundwater transformation processes.

Contributions

• Developed a novel two-stage runoff model based on the generalized proportionality hypothesis, providing a unified analytical framework for integrating surface and subsurface runoff generation.
• Offers a systematic understanding of the differential responses of streamflow components (surface runoff and baseflow) to climate change, addressing a significant research gap.
• Provides a valuable tool for coupled streamflow component assessment and informs adaptive water resource management strategies in changing environments.

Funding

• No explicit funding projects, programs, or reference codes were provided in the paper text.

Citation

@article{Yan2026Projecting,
  author = {Yan, Xin and Feng, Qi and Liu, Wei and Wei, Xiaohua and Zhu, Meng and Yang, Lianmei and Li, Zhi},
  title = {Projecting the changes in streamflow components based on the generalized proportionality hypothesis},
  journal = {Journal of Hydrology},
  year = {2026},
  doi = {10.1016/j.jhydrol.2025.134902},
  url = {https://doi.org/10.1016/j.jhydrol.2025.134902}
}