Treat, Claire C; Fuchs, Matthias; Laurent, Mélissa (2023): Below-ground carbon stocks, soil properties, and potential CO2 and CH4 production in the central Lena River Delta, Kurungnakh and Samoylov Islands from 12 permafrost profiles sampled in 2018 [dataset bundled publication]. PANGAEA, https://doi.org/10.1594/PANGAEA.959669

Arctic warming increases the degradation of permafrost soils but little is known about floodplain soils and other permafrost soils in the permafrost region. This dataset present soil properties from twelve analyzed cores located in the northeastern Siberian Lena River Delta within the continuous permafrost zone in northern Yakutia, Russia that were sampled in 2018. The cores represent intact yedoma, yedoma thaw slumps, and floodplain profiles. The soil coring and sampling was carried out in August 2018 for a total of 30 soil cores, 35 soil profiles, and 341 sediment samples. First, vegetation and other characteristics of the plots were described. Then, the active layer soils were excavated, described, and sampled with a fixed volume cylinder (250 cm³). Then the permafrost layers were sampled with a modified, snow, ice, and permafrost (SIPRE) auger to a depth of 1 m (core diameter of 7.62 cm) and visually described in their characteristics. Each core was divided into subsamples with 5-10 cm length according to its facies horizons, transported frozen to Alfred Wegener Institute in Potsdam, and stored at -20 °C until analysis. A subset of these sediment samples (n=105 from 12 cores) were later analyzed in the laboratory for physical and chemical properties; this data is presented here. The analysis from these samples includes: water content, dry bulk density, gravimetric ice content, pH, conductivity, total organic carbon content, total inorganic carbon content, total carbon content, total nitrogen content, carbon density, TOC storage, and TN storage. Selected samples were further analyzed for radiocarbon, grain size analysis, and potential CH4 and CO2 production using aerobic and anaerobic soil incubations for 356-days at 20 °C.