A 1ĝ€¯km resolution soil organic carbon dataset for frozen ground in the Third Pole

Abstract

Soil organic carbon (SOC) is very important in the vulnerable ecological environment of the Third Pole; however, data regarding the spatial distribution of SOC are still scarce and uncertain. Based on multiple environmental variables and soil profile data from 458 pits (depth of 0-1ĝ€¯m) and 114 cores (depth of 0-3ĝ€¯m), this study uses a machine-learning approach to evaluate the SOC storage and spatial distribution at a depth interval of 0-3ĝ€¯m in the frozen ground area of the Third Pole region. Our results showed that SOC stocks (SOCSs) exhibited a decreasing spatial pattern from the southeast towards the northwest. The estimated SOC storage in the upper 3ĝ€¯m of the soil profile was 46.18ĝ€¯Pg for an area of 3.27×106ĝ€¯km2, which included 21.69 and 24.49ĝ€¯Pg for areas of permafrost and seasonally frozen ground, respectively. Our results provide information on the storage and patterns of SOCSs at a 1ĝ€¯km resolution for areas of frozen ground in the Third Pole region, thus providing a scientific basis for future studies pertaining to Earth system models. The dataset is open-access and available at 10.5281/zenodo.4293454 (Wang et al., 2020).