Extended Biogeochemical Processes during Winter in Degraded Permafrost Soils

The database presents physical and chemical properties of soil, soil pore water and river in Abisko (Sweden), at Stordalen Mire on a natural gradient of permafrost degradation (palsa, intermediate, and degraded palsa sites) between September and November 2021. The air and soil temperatures, and the soil water content (SWC) were monitored continuously with a temporal resolution of 10 minutes. The soil redox potential was monitored every 30 minutes. Samples of soil pore water (n = 270) were collected at palsa, intermediate and degraded palsa sites at 10, 30, and 60 cm depth (except 45 cm depth for the palsa site because the permafrost table reaches 50 cm depth). Downstream river waters (n = 17) were collected every three days. On soil pore water, we measured pH, conductivity, DOC (dissolved organic carbon) concentrations, major cations (Fe, Ca, K, Mg, Mn, Na, P, S, Si) concentrations, silicon isotopic composition (δ30Si), percentage of colloidal Si and SUVA (Specific ultraviolet absorbance) index. On river waters, we measured pH, conductivity, DOC concentrations, major cations (Fe, Ca, K, Mg, Mn, Na, P, S, Si) concentrations, silicon isotopic composition (δ30Si), percentage of colloidal Fe and SUVA (Specific ultraviolet absorbance) index.