Ren Shuai, Wang Tao, Ji Xinhui, Wei Liang, Wei Jianjun, Cao Yingfang, Ding Jinzhi
State Key Laboratory of Tibetan Plateau Earth System, Environment and Resources (TPESER), Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing, China.
University of Chinese Academy of Sciences, Beijing, China.
Nat Commun. 2025 Jul 30;16(1):6978. doi: 10.1038/s41467-025-62332-6.
Soil carbon stocks on the Tibetan Plateau are widely considered to be increasingly threatened by drastic climate warming and intensified livestock grazing. But it remains elusive due to unconstrained model projections. Here we integrate large-scale soil campaigns, soil incubation with paired grazing experiments to project impacts of climate change and grazing on soil carbon stocks in a three-pool soil carbon model. While Tibetan soils will act as a carbon sink, over half of the gains occur in active or unprotected pools, making them vulnerable to extreme events and grazing. Although thermokarst processes may not reverse this trend, continued livestock grazing at current levels, or even a transition to a forage-livestock balanced state, could nearly offset climate-induced benefits. We highlight the critical need to optimize grazing to sustain soil carbon sinks on the Tibetan Plateau, and emphasize the importance of incorporating grazing impacts on soil carbon stocks into Earth system models.
青藏高原的土壤碳储量被广泛认为正日益受到气候急剧变暖和牲畜放牧强度增加的威胁。但由于模型预测不受限制，其情况仍不明朗。在此，我们整合大规模土壤调查、土壤培养以及配对放牧实验，通过一个三库土壤碳模型来预测气候变化和放牧对土壤碳储量的影响。虽然青藏高原土壤将成为碳汇，但超过一半的碳增加发生在活性或未受保护的库中，这使其易受极端事件和放牧的影响。尽管热喀斯特过程可能不会扭转这一趋势，但以当前水平持续放牧，甚至向草畜平衡状态转变，几乎可以抵消气候带来的益处。我们强调了优化放牧以维持青藏高原土壤碳汇至关重要，同时强调将放牧对土壤碳储量的影响纳入地球系统模型的重要性。
