LANZHOU, Dec. 17 (Xinhua) -- A new study on the Qinghai-Tibet Plateau has provided key evidence for evaluating the permafrost carbon feedback in climate change, according to the Northwest Institute of Eco-Environment and Resources (NIEER) under the Chinese Academy of Sciences.
This quantitative research on alpine thaw slumps on the Qinghai-Tibet Plateau is of importance to the global climate change predictions and the alpine ecological protection of China, the NIEER said.
Conducted by NIEER researchers in collaboration with counterparts from multiple universities and research institutions of China and Denmark, the study has been published in the journal Nature Communications.
The Qinghai-Tibet Plateau, the world's largest high-altitude permafrost region, stores a vast amount of soil organic carbon. In recent years, thaw slumps and other thermokarst landforms have expanded amid climate warming and permafrost degradation.
Such conditions will impact the carbon cycle and climate feedbacks of the plateau's alpine ecosystem. Therefore, it is important to investigate the effects of thaw slumps on carbon dynamics in permafrost ecosystems, according to Jiang Guanli, a researcher at the NIEER.
In 2024 and 2025, the study team conducted systematic greenhouse gas flux observations in the hinterland of the Qinghai-Tibet Plateau, as well as quantified the thaw slumps-induced flux changes and the carbon budget of the study areas.
The study results indicated that thaw slumps significantly weakened the carbon-sink function of alpine grasslands on the plateau.
Exposed, vegetation-free surfaces halved respiration but reduced gross primary productivity by approximately four-fifths, producing a large increase in net CO2 release compared with undisturbed ground. Methane (CH4) uptake occurred but was too small to offset these losses, the study showed.
Through flux comparison observations based on the age differences of thaw slumps, the research team found that the impact of thaw slumps on the carbon budget of alpine grassland shows a single-peak trajectory on the timeline.
The results indicated that although all thermokarst landforms arise from the rapid thawing of permafrost, their effects on regional carbon dynamics vary in both direction and intensity, according to Jiang.
"Our study proposes to incorporate thermokarst landforms and their influence trajectories over time into terrestrial and climate models. It is of great significance for enhancing the reliability of global climate change predictions and supporting ecological protection and engineering construction decisions in China's alpine regions," Jiang said. ■
