Shen et al. (2026) Enhanced understanding of dominant drivers of Water Yield change across China through the improved coupled carbon and water model

Identification

• Journal: Hydrology and earth system sciences
• Year: 2026
• Date: 2026-07-03
• Authors: Hanbo Yang, Changming Li
• DOI: 10.5194/hess-30-4175-2026

Research Groups

• Department of Hydraulic Engineering, Tsinghua University
• State Key Laboratory of Hydroscience and Engineering, Tsinghua University
• School of Civil Engineering and Transportation, South China University of Technology

Short Summary

This study improved the coupled carbon and water (CCW) model by integrating dynamic water use efficiency to capture CO2 physiological effects. The results showed that climate change was the dominant driver of water yield changes across China from 1982 to 2017.

Objective

• Investigate the attribution of water yield changes in China using a scenario-based analysis framework.
• Quantify the individual and combined effects of climate, vegetation, and CO2 change on water yield.

Study Configuration

• Spatial Scale: National scale, with a spatial resolution of 0.1°.
• Temporal Scale: Annual to multi-year scales, covering the period from 1982 to 2017.

Methodology and Data

• Models used: Coupled Carbon and Water (CCW) model, improved by integrating dynamic water use efficiency.
• Data sources:
  • Vegetation data (NDVI)
  • Climate data (precipitation, temperature, relative humidity, solar radiation, atmospheric pressure)
  • Land use and land cover (LULC) data
  • CO2 concentration data from Mauna Loa Observatory

Main Results

• The improved CCW model showed strong linear correlations between observed and simulated annual water yield.
• Climate change was the dominant driver of water yield changes across China, accounting for over 70% of the total changes.
• Vegetation structural change was the second largest factor, with relative contributions reaching up to 40%.
• CO2 effects had limited direct absolute impacts but exerted 10%-40% relative influences through stomatal closure mechanisms.

Contributions

• This study provides a novel framework for attributing water yield changes in China using scenario-based analysis.
• The improved CCW model explicitly links vegetation dynamics and CO2 effects to actual evapotranspiration at grid scale.
• The results highlight the importance of considering climate, vegetation, and CO2 change when managing water resources in China.

Funding

• This research was funded by the National Natural Science Foundation of China (Grant No. 51879219).
• The study also received support from the State Key Laboratory of Hydroscience and Engineering, Tsinghua University.

Citation

@article{Shen2026Enhanced,
  author = {Shen, Huilan and Yang, Hanbo and Li, Changming},
  title = {Enhanced understanding of dominant drivers of Water Yield change across China through the improved coupled carbon and water model},
  journal = {Hydrology and earth system sciences},
  year = {2026},
  doi = {10.5194/hess-30-4175-2026},
  url = {https://doi.org/10.5194/hess-30-4175-2026}
}