Zhou Shengfang, Long Hao, Chen Weizhe, Qiu Chunjing, Zhang Can, Xing Hang, Zhang Jingran, Cheng Liangqing, Zhao Cheng, Cheng Jun, Ciais Philippe
Key Laboratory of Lake and Watershed Science for Water Security, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China.
State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing, China.
Nat Commun. 2025 Jan 26;16(1):1049. doi: 10.1038/s41467-025-56399-4.
Organic carbon burial (OCB) in lakes, a critical component of the global carbon cycle, surpasses that in oceans, yet its response to global warming and associated feedbacks remains poorly understood. Using a well-dated biomarker sequence from the southern Tibetan Plateau and a comprehensive analysis of Holocene total organic carbon variations in lakes across the region, here we demonstrate that lake OCB significantly declined throughout the Holocene, closely linked to changes in temperature seasonality. Process-based land surface model simulations clarified the key impact of temperature seasonality on OCB in lakes: increased seasonality in the early Holocene saw warmer summers enhancing ecosystem productivity and organic matter deposition, while cooler winters improved organic matter preservation. The Tibetan Plateau's heightened sensitivity to climate and ecosystem dynamics amplifies these effects. With declining temperature seasonality, we predict a significant slowdown or reduction in OCB across these lake sediments, leading to carbon emissions and amplified global warming.
湖泊中的有机碳埋藏（OCB）是全球碳循环的关键组成部分，其埋藏量超过了海洋中的有机碳埋藏量，然而，人们对其对全球变暖及相关反馈的响应仍知之甚少。利用来自青藏高原南部年代测定良好的生物标志物序列，并对该地区湖泊全新世总有机碳变化进行综合分析，我们在此证明，整个全新世湖泊有机碳埋藏量显著下降，这与温度季节性变化密切相关。基于过程的陆面模型模拟明确了温度季节性对湖泊有机碳埋藏的关键影响：全新世早期季节性增强，夏季变暖提高了生态系统生产力和有机质沉积，而冬季变冷则改善了有机质的保存。青藏高原对气候和生态系统动态变化的高度敏感性放大了这些影响。随着温度季节性下降，我们预测这些湖泊沉积物中的有机碳埋藏量将显著放缓或减少，从而导致碳排放和全球变暖加剧。
