Mishra Umakant, Hugelius Gustaf, Shelef Eitan, Yang Yuanhe, Strauss Jens, Lupachev Alexey, Harden Jennifer W, Jastrow Julie D, Ping Chien-Lu, Riley William J, Schuur Edward A G, Matamala Roser, Siewert Matthias, Nave Lucas E, Koven Charles D, Fuchs Matthias, Palmtag Juri, Kuhry Peter, Treat Claire C, Zubrzycki Sebastian, Hoffman Forrest M, Elberling Bo, Camill Philip, Veremeeva Alexandra, Orr Andrew
Environmental Science Division, Argonne National Laboratory, 9700 South Cass Avenue, Argonne, IL, USA.
Department of Physical Geography and Quaternary Geology, Stockholm University, Stockholm, Sweden.
Sci Adv. 2021 Feb 24;7(9). doi: 10.1126/sciadv.aaz5236. Print 2021 Feb.
Large stocks of soil organic carbon (SOC) have accumulated in the Northern Hemisphere permafrost region, but their current amounts and future fate remain uncertain. By analyzing dataset combining >2700 soil profiles with environmental variables in a geospatial framework, we generated spatially explicit estimates of permafrost-region SOC stocks, quantified spatial heterogeneity, and identified key environmental predictors. We estimated that Pg C are stored in the top 3 m of permafrost region soils. The greatest uncertainties occurred in circumpolar toe-slope positions and in flat areas of the Tibetan region. We found that soil wetness index and elevation are the dominant topographic controllers and surface air temperature (circumpolar region) and precipitation (Tibetan region) are significant climatic controllers of SOC stocks. Our results provide first high-resolution geospatial assessment of permafrost region SOC stocks and their relationships with environmental factors, which are crucial for modeling the response of permafrost affected soils to changing climate.
大量的土壤有机碳（SOC）已在北半球永久冻土区积累，但其当前储量和未来命运仍不确定。通过在地理空间框架中分析结合了2700多个土壤剖面与环境变量的数据集，我们生成了永久冻土区SOC储量的空间明确估计值，量化了空间异质性，并确定了关键的环境预测因子。我们估计，Pg C储存在永久冻土区土壤的顶部3米处。最大的不确定性出现在环极地趾坡位置和西藏地区的平坦区域。我们发现，土壤湿度指数和海拔是主要的地形控制因素，而地表气温（环极地区）和降水（西藏地区）是SOC储量的重要气候控制因素。我们的结果首次提供了对永久冻土区SOC储量及其与环境因素关系的高分辨率地理空间评估，这对于模拟受永久冻土影响的土壤对气候变化的响应至关重要。
