The lagged and cumulative effects of permafrost and seasonally frozen soil on water use efficiency in the Qilian Mountains, Northwest China
Abstract
Permafrost in the Qilian Mountains is highly sensitive to climate change, affecting ecosystem energy, water, and carbon cycling. Using MODIS data and the self-calibrated Palmer Drought Severity Index (scPDSI), we analyzed WUE dynamics and drought responses in permafrost and seasonally frozen soil regions during 2001-2020. WUE showed an overall gradual decline and an intra-annual increase-decrease-increase pattern, with growth rates peaking in November and the lowest values occurring in June. A threshold of 0.6 gC m-2 mm-1 demarcated the two frozen-soil types. Delayed drought responses occurred in 50.77% of vegetation, with a mean lag of 6.82 months; seasonally frozen soil mainly showed non-lagged and long-term responses, whereas permafrost mainly showed non-lagged and short-term responses. Cumulative effects affected 40.49% of vegetation, with a mean duration of 5.06 months. These findings provide a mechanistic basis for understanding drought impacts on vegetation WUE across contrasting frozen-soil environments.
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BibTeX
@article{li2026lagged,
title = {{The lagged and cumulative effects of permafrost and seasonally frozen soil on water use efficiency in the Qilian Mountains, Northwest China}},
author = {Lili Li and Yu Guo and Yao Zhang and Duni Jia and Jia Du and Yong Gu and Tianxu Luo and Jinshan Li and Dawei Wang},
journal = {iScience},
year = {2026},
month = oct,
doi = {10.1016/j.isci.2026.117973},
url = {https://www.cell.com/iscience/fulltext/S2589-0042(26)03356-0},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - The lagged and cumulative effects of permafrost and seasonally frozen soil on water use efficiency in the Qilian Mountains, Northwest China
AU - Lili Li
AU - Yu Guo
AU - Yao Zhang
AU - Duni Jia
AU - Jia Du
AU - Yong Gu
AU - Tianxu Luo
AU - Jinshan Li
AU - Dawei Wang
PY - 2026
DA - 2026/10/29
JO - iScience
DO - 10.1016/j.isci.2026.117973
UR - https://www.cell.com/iscience/fulltext/S2589-0042(26)03356-0
AB - Permafrost in the Qilian Mountains is highly sensitive to climate change, affecting ecosystem energy, water, and carbon cycling. Using MODIS data and the self-calibrated Palmer Drought Severity Index (scPDSI), we analyzed WUE dynamics and drought responses in permafrost and seasonally frozen soil regions during 2001-2020. WUE showed an overall gradual decline and an intra-annual increase-decrease-increase pattern, with growth rates peaking in November and the lowest values occurring in June. A threshold of 0.6 gC m-2 mm-1 demarcated the two frozen-soil types. Delayed drought responses occurred in 50.77% of vegetation, with a mean lag of 6.82 months; seasonally frozen soil mainly showed non-lagged and long-term responses, whereas permafrost mainly showed non-lagged and short-term responses. Cumulative effects affected 40.49% of vegetation, with a mean duration of 5.06 months. These findings provide a mechanistic basis for understanding drought impacts on vegetation WUE across contrasting frozen-soil environments.
SN - 2589-0042
ER -