Unstable carbon sink growth in alpine grasslands of the Qinghai–Tibet Plateau
Abstract
IntroductionAlpine grasslands on the Qinghai–Tibet Plateau (QTP) are central to regional carbon cycling and climate regulation. Although warming and increasing precipitation have driven widespread greening and greater carbon uptake, it remains uncertain whether these gains are accompanied by greater ecosystem stability.MethodsWe examined carbon sink capacity and temporal variability using net ecosystem productivity (NEP) and proportional variability (PV), and assessed recovery resilience indirectly using lag-one autocorrelation (TAC) as a conditional proxy. Grasslands were classified into eight types based on the trend directions of NEP, PV, and TAC. Multivariate spatial regressions were used to examine hydroclimatic associations with these trends.ResultsAnnual NEP increased across 81.7% of the grassland area between 2000 and 2024, with significant increases (p < 0.05) across 31.7%. Plateau-scale mean annual NEP increased significantly at 0.553 g C m⁻² yr⁻² (p = 0.006). Regional mean PV and TAC also increased, indicating greater temporal fluctuations and potentially slower recovery under the assumptions underlying TAC. Robust sinks (T1), with increasing NEP and declining PV and TAC, covered 20.2% of grasslands, whereas 61.6% belonged to T2–T4, where increasing NEP co-occurred with rising PV, TAC, or both. Vulnerable sinks were the largest category (32.6%) and were concentrated in semi-arid alpine steppes and alpine deserts, whereas robust sinks occurred mainly in eastern alpine meadows. Mean annual precipitation was the strongest predictor associated with NEP trends, and vapor pressure deficit was the strongest predictor associated with PV and TAC trends.DiscussionStronger carbon uptake does not necessarily translate into a more stable ecosystem. Evaluating carbon uptake together with temporal variability and conditional resilience indicators can inform assessments of QTP alpine grasslands under climate stress.
Related
- Combined Return Synergizes Aboveground Photosynthesis and Subsurface Soil Organic Carbon Stock to Boost Spring Wheat Yield in the Qinghai–Tibet Plateau
- Evolutionary genomics of ancient and endangered Achnatherum breviaristatum on the Qinghai-Tibet Plateau
- Predicting the Potential Climatic Suitability of Typical Poisonous Weeds on the Qinghai–Tibet Plateau Under Climate Change Using Biomod2 and a Single Global Climate Model
- Hydrodynamics rather than water temperature shapes the macroinvertebrate communities in alpine rivers on the Qinghai–Xizang Plateau
- Mapping and dynamic monitoring of desertification on the Qinghai-Tibetan Plateau using surface Albedo and Solar-Induced Chlorophyll Fluorescence
BibTeX
@article{zhou2026unstable,
title = {{Unstable carbon sink growth in alpine grasslands of the Qinghai–Tibet Plateau}},
author = {Anqi Zhou and Meng Li and Chuhan Li and Yunfei Feng and Yuting Yang},
journal = {Frontiers in Plant Science},
year = {2026},
month = nov,
doi = {10.3389/fpls.2026.1993299},
url = {https://www.frontiersin.org/articles/10.3389/fpls.2026.1993299},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Unstable carbon sink growth in alpine grasslands of the Qinghai–Tibet Plateau
AU - Anqi Zhou
AU - Meng Li
AU - Chuhan Li
AU - Yunfei Feng
AU - Yuting Yang
PY - 2026
DA - 2026/11/04
JO - Frontiers in Plant Science
DO - 10.3389/fpls.2026.1993299
UR - https://www.frontiersin.org/articles/10.3389/fpls.2026.1993299
AB - IntroductionAlpine grasslands on the Qinghai–Tibet Plateau (QTP) are central to regional carbon cycling and climate regulation. Although warming and increasing precipitation have driven widespread greening and greater carbon uptake, it remains uncertain whether these gains are accompanied by greater ecosystem stability.MethodsWe examined carbon sink capacity and temporal variability using net ecosystem productivity (NEP) and proportional variability (PV), and assessed recovery resilience indirectly using lag-one autocorrelation (TAC) as a conditional proxy. Grasslands were classified into eight types based on the trend directions of NEP, PV, and TAC. Multivariate spatial regressions were used to examine hydroclimatic associations with these trends.ResultsAnnual NEP increased across 81.7% of the grassland area between 2000 and 2024, with significant increases (p < 0.05) across 31.7%. Plateau-scale mean annual NEP increased significantly at 0.553 g C m⁻² yr⁻² (p = 0.006). Regional mean PV and TAC also increased, indicating greater temporal fluctuations and potentially slower recovery under the assumptions underlying TAC. Robust sinks (T1), with increasing NEP and declining PV and TAC, covered 20.2% of grasslands, whereas 61.6% belonged to T2–T4, where increasing NEP co-occurred with rising PV, TAC, or both. Vulnerable sinks were the largest category (32.6%) and were concentrated in semi-arid alpine steppes and alpine deserts, whereas robust sinks occurred mainly in eastern alpine meadows. Mean annual precipitation was the strongest predictor associated with NEP trends, and vapor pressure deficit was the strongest predictor associated with PV and TAC trends.DiscussionStronger carbon uptake does not necessarily translate into a more stable ecosystem. Evaluating carbon uptake together with temporal variability and conditional resilience indicators can inform assessments of QTP alpine grasslands under climate stress.
SN - 1664-462X
ER -