Ma et al. (2026) A composite ecological drought index integrating multi-source water and heat stress with time-lag effects: Insights from the Yellow River Basin

Identification

• Journal: Journal of Environmental Management
• Year: 2026
• Date: 2026-02-13
• Authors: Jingtian Ma, Lianqing Xue, Yuanhong Liu, SaiHua Liu, Ruoshi Xu
• DOI: 10.1016/j.jenvman.2026.128938

Research Groups

• College of Hydrology and Water Resources, Hohai University, Nanjing 210098, China
• School of Hydraulic Engineering, Wanjiang University of Technology, Anhui 243031, China

Short Summary

This study proposes a Composite Ecological Drought Index (CEDI) using a trivariate copula framework to integrate multi-source water and heat stress with time-lag effects. Applied to the Yellow River Basin, CEDI effectively characterizes ecological drought and vegetation resistance, revealing a general weakening of drought over the past two decades despite regional vulnerabilities.

Objective

• To develop a Composite Ecological Drought Index (CEDI) that integrates precipitation, soil moisture, and evapotranspiration deficit within a trivariate copula framework, explicitly accounting for time-lag effects during drought propagation.
• To apply CEDI to the Yellow River Basin (YRB) to examine the spatiotemporal evolution of ecological drought and vegetation resistance across different climatic regions and land-use types.

Study Configuration

• Spatial Scale: Yellow River Basin (YRB)
• Temporal Scale: Past two decades (approximately 20 years)

Methodology and Data

• Models used: Composite Ecological Drought Index (CEDI) based on a trivariate copula framework.
• Data sources: Integrates precipitation, soil moisture, and evapotranspiration deficit (implied from the variables used in the CEDI framework).

Main Results

• CEDI provides a superior characterization of ecosystem drought responses compared to traditional indices, effectively capturing multi-source stressors and time-lag effects.
• Ecological drought in the Yellow River Basin has generally weakened over the past two decades, coinciding with widespread vegetation greening.
• Climate region I consistently remains the most drought-prone area within the YRB, exhibiting the highest drought severity.
• Vegetation resistance shows significant spatial and seasonal heterogeneity, with higher resistance observed in climate region II and lower resistance in region I, and distinct seasonal variations among land-use types influenced by irrigation and management.

Contributions

• Introduction of a novel Composite Ecological Drought Index (CEDI) that comprehensively integrates multi-source water and heat stress (precipitation, soil moisture, evapotranspiration deficit) and explicitly incorporates time-lag effects using a robust trivariate copula framework.
• Provides a physically informed and statistically robust framework for integrated ecological drought assessment, addressing limitations of existing indices.
• Enhances the understanding of drought propagation mechanisms and ecosystem resistance dynamics in heterogeneous landscapes, specifically within the Yellow River Basin.

Funding

• Not mentioned in the provided text.

Citation

@article{Ma2026composite,
  author = {Ma, Jingtian and Xue, Lianqing and Liu, Yuanhong and Liu, SaiHua and Xu, Ruoshi},
  title = {A composite ecological drought index integrating multi-source water and heat stress with time-lag effects: Insights from the Yellow River Basin},
  journal = {Journal of Environmental Management},
  year = {2026},
  doi = {10.1016/j.jenvman.2026.128938},
  url = {https://doi.org/10.1016/j.jenvman.2026.128938}
}