Ji et al. (2026) Contrasting feedback mechanisms drive basin-scale vegetation vulnerability to drought in cold-arid northern China

Identification

• Journal: Journal of Environmental Management
• Year: 2026
• Date: 2026-02-11
• Authors: Jianguo Ji, Yixuan Wang, Tingxi Liu, Limin Duan, Long Ma, Shiyu Zhang, Xuan Zhang, Wenbo Song
• DOI: 10.1016/j.jenvman.2026.128929

Research Groups

• State Key Laboratory of Water Engineering Ecology and Environment in Arid Area, Inner Mongolia Agricultural University, Hohhot, 010018, China
• College of Water Conservancy and Civil Engineering, Inner Mongolia Agricultural University, Hohhot, 010018, China
• Inner Mongolia Key Laboratory of Ecohydrology and High-Efficient Utilization of Water Resources, College of Water Conservancy and Civil Engineering, Inner Mongolia Agricultural University, Hohhot, 010018, China
• Autonomous Region Collaborative Innovation Center for Integrated Management of Water Resources and Water Environment in the Inner Mongolia Reaches of the Yellow River, Hohhot, 010018, China

Short Summary

This study developed a basin-scale framework using the Standardized Precipitation Evapotranspiration Index (SPEI) and a Composite Vegetation Index (CVI) to assess vegetation vulnerability to drought in cold-arid northern China, revealing spatially differentiated vulnerability driven by contrasting negative and positive feedback mechanisms.

Objective

• To establish a basin-scale framework for assessing vegetation vulnerability to drought in cold-arid northern China, overcoming limitations of static drought-vegetation response assumptions, and to systematically quantify vegetation resistance, resilience, vulnerability, and critical drought thresholds.

Study Configuration

• Spatial Scale: Five representative basins in the cold-arid regions of northern China, including the Hailar River Basin (eastern), Heihe River Basin (central), and Tarim River Basin (western).
• Temporal Scale: Growing seasons over an unspecified recent period, focusing on vegetation-anomaly-inducing drought events.

Methodology and Data

• Models used: Standardized Precipitation Evapotranspiration Index (SPEI), Composite Vegetation Index (CVI).
• Data sources: Not explicitly detailed in the provided text, but involves precipitation, evapotranspiration, and vegetation data used to derive SPEI and CVI.

Main Results

• The duration of vegetation-anomaly-inducing drought events gradually increased from 2.1 months in the eastern basin to 3.8 months in the western basin, while the peak intensity declined from 1.37 to 1.21.
• Vegetation anomalies in eastern meadow and typical steppe basins are associated with shorter-duration but more intense drought events, whereas western desert and desert-steppe basins are linked to longer-duration droughts of moderate peak intensity.
• From the eastern Hailar River Basin to the central Heihe River Basin and further to the western Tarim River Basin, both vegetation resistance and resilience exhibited a decreasing-then-increasing trend, resulting in a corresponding rise and subsequent decline in vulnerability (from 0.36 to 0.66 and then to 0.37).
• Drought severity and duration thresholds were generally higher in the eastern basin (0.89 and 0.68 months, respectively) but lower in the western basin (0.61 and 0.57 months, respectively).
• Spatial differentiation in vulnerability is driven by contrasting feedback mechanisms: low-vulnerable eastern basins exhibit a self-regulating negative feedback where hydrological improvements promote vegetation recovery, while high-vulnerability western basins show a self-reinforcing positive feedback where moisture depletion leads to vegetation degradation and intensified drought stress.

Contributions

• Established a novel basin-scale framework for assessing vegetation vulnerability to drought in cold-arid regions, moving beyond static drought-vegetation response assumptions.
• Systematically quantified vegetation resistance, resilience, vulnerability, and critical thresholds for drought severity and duration across diverse cold-arid basins.
• Identified and explained the dominance of contrasting threshold-dependent feedback mechanisms (negative in the east, positive in the west) as key drivers of spatial differentiation in vegetation drought vulnerability.

Funding

• Not explicitly detailed in the provided text.

Citation

@article{Ji2026Contrasting,
  author = {Ji, Jianguo and Wang, Yixuan and Liu, Tingxi and Duan, Limin and Ma, Long and Zhang, Shiyu and Zhang, Xuan and Song, Wenbo},
  title = {Contrasting feedback mechanisms drive basin-scale vegetation vulnerability to drought in cold-arid northern China},
  journal = {Journal of Environmental Management},
  year = {2026},
  doi = {10.1016/j.jenvman.2026.128929},
  url = {https://doi.org/10.1016/j.jenvman.2026.128929}
}