Soil and incubation data of permafrost-affected soils of the northeast Siberian polygonal tundra

The large amounts of soil organic matter (SOM) in permafrost-affected soils are prone to increased microbial decomposition in a warming climate. The environmental parameters regulating the production of carbon dioxide (CO2) and methane (CH4), however, are insufficiently understood to confidently predict the feedback of thawing permafrost to global warming. Therefore, the effects of oxygen availability, freezing and thawing, temperature, and labile organic matter (OM) additions on greenhouse gas production were studied in northeast Siberian polygonal tundra soils, including the seasonally thawed active layer and upper perennially frozen permafrost. Soils were incubated at constant temperatures of 1 °C, 4 °C, or 8 °C for up to 150 days. CO2 production in surface layers was three times higher than in the deeper soil. Under anaerobic conditions, SOM decomposition was 2-6 times lower than under aerobic conditions and more CO2 than CH4 was produced. […]