Lu et al. (2026) Dynamic hazard assessment of compound drought and heat events in maize based on a soil-temperature-integrated index in Songliao Plain

Identification

• Journal: European Journal of Agronomy
• Year: 2026
• Date: 2026-01-07
• Authors: Xianwei Lu, Sicheng Wei, Ying Guo, Cha Ersi, D. Chen, Ziyuan Zhou, Yue Cong Li, Yuping Dong, Zhijun Tong, Xingpeng Liu, Jiquan Zhang, Chunli Zhao, Yanxia Zhao
• DOI: 10.1016/j.eja.2026.127984

Research Groups

• School of Environment, Northeast Normal University, Changchun 130024, China
• State Environmental Protection Key Laboratory of Wetland Ecology and Vegetation Restoration, Changchun 130024, China
• Jilin Province Science and Technology Innovation Center of Agro-meteorological Disaster Risk Assessment and Prevention, Changchun 130024, China
• Key Laboratory for Vegetation Ecology, Ministry of Education, Changchun 130024, China
• College of Forestry and Grassland, Jilin Agricultural University, Changchun 130024, China
• Department of Atmospheric and Oceanic Sciences & Institute of Atmospheric Science, Fudan University, Shanghai 200438, China

Short Summary

This study developed a novel soil-temperature-integrated Compound Drought and Heat Event Index (CDHEI) to dynamically assess the hazard of compound drought and heat events (CDHEs) in maize in the Songliao Plain, revealing their increasing frequency and intensity since 2000 and a strong correlation with maize yield loss, particularly highlighting the dominant role of soil temperature.

Objective

• To develop a soil-temperature-integrated Compound Drought and Heat Event Index (CDHEI) for dynamic hazard assessment of compound drought and heat events (CDHEs) in maize.
• To systematically assess the spatiotemporal characteristics and hazard levels of CDHEs in the Songliao Plain.
• To evaluate the role of soil temperature in CDHE occurrence and crop stress.

Study Configuration

• Spatial Scale: Songliao Plain, China
• Temporal Scale: 1982–2021 (40 years)

Methodology and Data

• Models used:
  • Compound Drought and Heat Event Index (CDHEI) (newly developed)
  • Run theory for event identification
  • Random forest for importance assessment
• Data sources:
  • ERA5-Land dataset
  • SPEI-GD datasets

Main Results

• Compound drought and heat events (CDHEs) were mainly concentrated in the northwest and southwest regions of the Songliao Plain.
• A critical breakpoint was identified around the year 2000, after which CDHE frequency and intensity significantly increased in the 21st century.
• The developed CDHEI showed a strong correlation with maize yield loss, with a maximum correlation coefficient of 0.749 (p < 0.05), particularly in the southwestern and northwestern regions.
• Compared to existing indices, CDHEI improved correlation with yield loss by 13 % to over 100 %.
• Dynamic hazard assessment identified Baicheng, Songyuan, and surrounding areas as high-hazard-level zones.
• Soil temperature (SSTI) had the highest importance in event evolution, underscoring its dominant role in CDHE intensification.

Contributions

• Development of a novel soil-temperature-integrated Compound Drought and Heat Event Index (CDHEI) that significantly improves the assessment of CDHE impacts on maize yield.
• Highlighting the indispensable role of soil temperature and soil processes in monitoring compound extreme events and their agricultural impacts, a factor largely overlooked previously.
• Providing a scientific basis for agricultural risk assessment and regional adaptation strategies in the Songliao Plain.

Funding

• Not specified in the provided text.

Citation

@article{Lu2026Dynamic,
  author = {Lu, Xianwei and Wei, Sicheng and Guo, Ying and Ersi, Cha and Chen, D. and Zhou, Ziyuan and Li, Yue Cong and Dong, Yuping and Tong, Zhijun and Liu, Xingpeng and Zhang, Jiquan and Zhao, Chunli and Zhao, Yanxia},
  title = {Dynamic hazard assessment of compound drought and heat events in maize based on a soil-temperature-integrated index in Songliao Plain},
  journal = {European Journal of Agronomy},
  year = {2026},
  doi = {10.1016/j.eja.2026.127984},
  url = {https://doi.org/10.1016/j.eja.2026.127984}
}