Xiong et al. (2026) Stage-specific drought impacts and the mitigating role of irrigation on maize yield: evidence from satellite remote sensing

Identification

• Journal: Frontiers in Sustainable Food Systems
• Year: 2026
• Date: 2026-03-31
• Authors: Lu Xiong, Long Chen, Chenhui Di, Abbas Ali Chandio, Shengwei Wang, Dayu Liu, Yongen Zhang, Xin Dai
• DOI: 10.3389/fsufs.2026.1783406

Research Groups

• Agricultural Information Institute of CAAS, Beijing, China
• Key Laboratory of Agricultural Monitoring and Early Warning Technology, Ministry of Agriculture and Rural Affairs, Beijing, China
• Laboratory for Intelligent Food Security Governance, Huazhong Agricultural University, Wuhan, China
• School of Economics, Guizhou University, Guiyang, China
• Henan Yunfei Technology Development Co., Ltd., Zhengzhou, China

Short Summary

This study investigated the stage-specific impacts of drought on maize yield and the mitigating role of irrigation investment in Henan Province, China, finding that drought significantly reduces yield, especially during tasseling and maturity, while irrigation acts as crucial climate insurance by sustaining vegetation vigor.

Objective

• To determine whether and how the impact of drought on maize yield varies across specific growth stages, identifying the most sensitive critical windows.
• To assess to what extent irrigation mitigates drought-induced yield losses and whether this mitigation effect is stage-dependent.
• To examine whether satellite-derived vegetation indices (Normalized Difference Vegetation Index - NDVI) can elucidate the physiological pathway through which drought suppresses crop growth and how irrigation moderates this process.

Study Configuration

• Spatial Scale: County-level regions in Henan Province, China, covering approximately 167,000 square kilometers.
• Temporal Scale: 2013 to 2022 (10 years). Maize growth cycle segmented into five distinct phases: Sowing (April 11–April 20), Seedling Emergence (April 21–May 24), Jointing (May 25–June 24), Tasseling (June 25–August 10), and Maturity (August 11–September 30).

Methodology and Data

• Models used: Two-way fixed effects model (county and year fixed effects), hierarchical regression model for moderating effects, and a stepwise approach for mediation analysis. Robustness checks included using a Random Effects (RE) model.
• Data sources:
  • Remote Sensing Data: Daily gap-free Normalized Difference Vegetation Index (NDVI) dataset (2013-2022) derived from NOAA observations, aggregated to county-level.
  • Meteorological Data: Daily records from national weather stations (2013-2022) via the China Meteorological Data Service Center, converted to county-level units using a distance-weighted averaging method. Variables included Munger’s Index (drought severity), heatwave frequency, growing degree days (GDD), and cumulative precipitation (PREC).
  • Production Input–Output Data: Agricultural statistics (crop yields, sown areas, production conditions) and socio-economic variables sourced from the China Statistical Yearbook and the China Rural Statistical Yearbook.

Main Results

• Agricultural drought significantly negatively impacts maize yield, with a one-unit increase in drought severity associated with a yield reduction of approximately 1.46 tonnes per hectare (t/ha).
• Drought impacts exhibit pronounced heterogeneity across growth stages: the Tasseling and Maturity stages were identified as the most vulnerable "critical windows," where yield losses reached 0.79 t/ha and 0.78 t/ha, respectively, per one-unit increase in drought index. Impacts during vegetative stages (sowing, emergence, jointing) were statistically insignificant.
• Irrigation serves as vital "climate insurance," significantly attenuating drought-induced marginal yield losses. A one-unit improvement in irrigation conditions reduced the marginal yield loss attributed to drought by 5.0227 t/ha. This mitigating effect was particularly pronounced during the Tasseling and Maturity stages.
• Satellite remote sensing evidence via NDVI mediation analysis substantiated that drought during critical periods significantly suppresses vegetation vigor (reduces NDVI), which in turn leads to yield loss. Irrigation effectively mitigates this NDVI suppression, thereby maintaining crop physiological activity and buffering yield.
• Vegetation vigor (NDVI) during the Tasseling and Maturity stages showed a significant positive correlation with final maize yield.

Contributions

• Provides large-scale statistical evidence, using high-frequency data, to identify heterogeneous drought impacts across specific maize growth stages in a major agricultural region (Henan Province, China).
• Systematically evaluates the stage-specific efficacy of irrigation in mitigating drought shocks, revealing the physiological pathways (via NDVI) through which irrigation maintains crop health during sensitive phenological phases.
• Offers targeted evidence for precision irrigation scheduling and climate-resilient agricultural planning, providing a crucial hydrological foundation to optimize systemic frameworks like Integrated Soil-Crop System Management (ISSM) by emphasizing synergistic "water-nitrogen coupling."

Funding

• National Key Research and Development Program of China (Grant number: 2023YFD2302800).

Citation

@article{Xiong2026Stagespecific,
  author = {Xiong, Lu and Chen, Long and Di, Chenhui and Chandio, Abbas Ali and Wang, Shengwei and Liu, Dayu and Zhang, Yongen and Dai, Xin},
  title = {Stage-specific drought impacts and the mitigating role of irrigation on maize yield: evidence from satellite remote sensing},
  journal = {Frontiers in Sustainable Food Systems},
  year = {2026},
  doi = {10.3389/fsufs.2026.1783406},
  url = {https://doi.org/10.3389/fsufs.2026.1783406}
}