Gong et al. (2026) Stage-specific water-heat mismatches and cumulative risk of extreme hydroclimatic events to double-season and mid-season rice yields in subtropical China

Identification

• Journal: Agricultural Water Management
• Year: 2026
• Date: 2026-09-15
• Authors: Rouyan Gong, Guangsheng Xiang, Yi Gong, Jiahao Wu, Qihang Liu, Jianjun Fu, Wenjuan Guo
• DOI: 10.1016/j.agwat.2026.110774

Research Groups

• School of Water Conservancy and Civil Engineering, Hunan Agricultural University
• The Hunan Engineering Technology Research Center of Precise Control Irrigation for Irrigation Districts
• The Hunan Water Resources Center
• Chenzhou Laboratory

Short Summary

This study evaluates the impacts of extreme hydroclimatic events and stage-specific water-heat mismatches on double-season and mid-season rice systems in subtropical China. A novel Stage-specific Rice Water Deficit Index (SRWDI) was introduced to precisely capture the intensity of hydro-thermal imbalances during specific phenological windows.

Objective

• To reveal the spatiotemporal distribution and interdecadal evolution trends of thermal resources and precipitation across six key phenological stages for early, mid-season, and late rice.
• To extract the detrended relative meteorological yield and evaluate its spatial heterogeneity and interannual variations to isolate pure climate-driven impacts.
• To quantitatively identify the most vulnerable phenological stages to compound water-heat mismatches (characterized by the newly defined SRWDI) via LOOCV-validated stepwise multiple linear regression.

Study Configuration

• Spatial Scale: Hunan Province, southeastern China
• Temporal Scale: 1960–2022

Methodology and Data

• Models used: Multiple linear regression, Stepwise regression, Leave-One-Out Cross-Validation (LOOCV)
• Data sources: National Meteorological Information Center (NMIC) of the China Meteorological Administration (CMA), Department of Agriculture of Hunan Province

Main Results

• The study found that mid-season and late rice are highly vulnerable to meteorological yield risks driven by early-to-mid stage hydro-thermal imbalances.
• The Stage-specific Rice Water Deficit Index (SRWDI) was identified as a critical indicator for assessing agro-climatic risks during specific phenological stages.
• The relative contribution rate of each retained variable in the final model indicates that the transplanting-tillering (TR-TI) and panicle initiation-booting (PI-BO) stages exerted the most significant negative impacts on actual meteorological yields, with relative contribution rates of 42.6% and 21.36%, respectively.

Contributions

• This study provides a robust theoretical basis for optimizing cropping calendars and enhancing adaptive agricultural water management in multi-cropping systems.
• The novel Stage-specific Rice Water Deficit Index (SRWDI) was introduced to precisely capture the intensity of hydro-thermal imbalances during specific phenological windows, providing a critical indicator for assessing agro-climatic risks.

Funding

• This research was funded by the Hunan Engineering Technology Research Center of Precise Control Irrigation for Irrigation Districts.

Citation

@article{Gong2026Stagespecific,
  author = {Gong, Rouyan and Xiang, Guangsheng and Gong, Yi and Wu, Jiahao and Liu, Qihang and Fu, Jianjun and Guo, Wenjuan},
  title = {Stage-specific water-heat mismatches and cumulative risk of extreme hydroclimatic events to double-season and mid-season rice yields in subtropical China},
  journal = {Agricultural Water Management},
  year = {2026},
  doi = {10.1016/j.agwat.2026.110774},
  url = {https://doi.org/10.1016/j.agwat.2026.110774}
}