Treat Claire C, Kleinen Thomas, Broothaerts Nils, Dalton April S, Dommain René, Douglas Thomas A, Drexler Judith Z, Finkelstein Sarah A, Grosse Guido, Hope Geoffrey, Hutchings Jack, Jones Miriam C, Kuhry Peter, Lacourse Terri, Lähteenoja Outi, Loisel Julie, Notebaert Bastiaan, Payne Richard J, Peteet Dorothy M, Sannel A Britta K, Stelling Jonathan M, Strauss Jens, Swindles Graeme T, Talbot Julie, Tarnocai Charles, Verstraeten Gert, Williams Christopher J, Xia Zhengyu, Yu Zicheng, Väliranta Minna, Hättestrand Martina, Alexanderson Helena, Brovkin Victor
Department of Environmental and Biological Sciences, University of Eastern Finland, 70211 Kuopio, Finland;
Land in the Earth System, Max Planck Institute for Meteorology, 20146 Hamburg, Germany.
Proc Natl Acad Sci U S A. 2019 Mar 12;116(11):4822-4827. doi: 10.1073/pnas.1813305116. Epub 2019 Feb 25.
Glacial-interglacial variations in CO and methane in polar ice cores have been attributed, in part, to changes in global wetland extent, but the wetland distribution before the Last Glacial Maximum (LGM, 21 ka to 18 ka) remains virtually unknown. We present a study of global peatland extent and carbon (C) stocks through the last glacial cycle (130 ka to present) using a newly compiled database of 1,063 detailed stratigraphic records of peat deposits buried by mineral sediments, as well as a global peatland model. Quantitative agreement between modeling and observations shows extensive peat accumulation before the LGM in northern latitudes (>40°N), particularly during warmer periods including the last interglacial (130 ka to 116 ka, MIS 5e) and the interstadial (57 ka to 29 ka, MIS 3). During cooling periods of glacial advance and permafrost formation, the burial of northern peatlands by glaciers and mineral sediments decreased active peatland extent, thickness, and modeled C stocks by 70 to 90% from warmer times. Tropical peatland extent and C stocks show little temporal variation throughout the study period. While the increased burial of northern peats was correlated with cooling periods, the burial of tropical peat was predominately driven by changes in sea level and regional hydrology. Peat burial by mineral sediments represents a mechanism for long-term terrestrial C storage in the Earth system. These results show that northern peatlands accumulate significant C stocks during warmer times, indicating their potential for C sequestration during the warming Anthropocene.
极地冰芯中一氧化碳和甲烷的冰期 - 间冰期变化，部分归因于全球湿地范围的变化，但末次盛冰期（LGM，距今21000年至18000年）之前的湿地分布几乎仍不为人知。我们利用一个新编制的包含1063条由矿物沉积物掩埋的泥炭沉积详细地层记录的数据库以及一个全球泥炭地模型，对末次冰期旋回（距今130000年至今）期间的全球泥炭地范围和碳储量进行了研究。模型与观测结果之间的定量一致性表明，在北纬地区（>40°N），末次盛冰期之前存在广泛的泥炭积累，特别是在包括末次间冰期（距今130000年至116000年，MIS 5e）和间冰段（距今57000年至29000年，MIS 3）在内的较温暖时期。在冰川前进和永久冻土形成的冷却期，冰川和矿物沉积物对北方泥炭地的掩埋使活跃泥炭地范围、厚度以及模拟的碳储量较温暖时期减少了70%至90%。在整个研究期间，热带泥炭地范围和碳储量几乎没有时间变化。虽然北方泥炭掩埋增加与冷却期相关，但热带泥炭的掩埋主要受海平面和区域水文变化驱动。矿物沉积物对泥炭的掩埋是地球系统中陆地碳长期储存的一种机制。这些结果表明，北方泥炭地在较温暖时期积累了大量碳储量，表明它们在变暖的人类世具有碳固存潜力。
