Establishing Relationships Between Organic Carbon Storage, Soil Water Content, and Vegetation Cover With Freeze-Thaw Deformation in the Arctic

In this study, we jointly analyzed InSAR data and 202 soil core samples collected at various sites across ∼7,500 km
²
area near the Toolik Field Station. To compare point-wise field measurements with regional InSAR estimation, we derived PDFs from our field and lab measurements to better characterize regional soil properties and applied a Monte Carlo-based simulation. The joint analysis allowed us to prove that the InSAR-observed seasonal thaw subsidence measures the amount of water stored in the saturated soil active layer above permafrost. In the Toolik area, 95% of the soil water equivalent depth estimates range from 0 to 66 cm in the Toolik area. Field data was then used to study the interrelationship between soil properties, land cover types, seasonal thaw subsidence, and soil carbon storage. We found that the land cover type with thicker catotelm tends to store more soil carbon and produce greater seasonal thaw. As a result, we highlight the importance of land cover type and catotelm thickness in predicting the amount of thaw subsidence and soil organic carbon storage.