Degradation of permafrost carbon in the Kolyma River ...

• Main Authors: Keskitalo, Kirsi, Bröder, Lisa, Jong, Dirk, Zimov, Nikita, Davydova, Anya, Davydov, Sergey, Tesi, Tommaso, Mann, Paul, Haghipour, Negar, Eglinton, Timothy I., Vonk, Jorien
• Format: Text
• Language: English
• Published: ETH Zurich 2020
• Subjects: kolyma river; permafrost; Thermokarst
• Online Access: https://dx.doi.org/10.3929/ethz-b-000456969; http://hdl.handle.net/20.500.11850/456969

Soil temperatures in permafrost (i.e. perennially frozen ground) are rising globally. The increasing temperatures accelerate permafrost thaw and release of organic carbon, that has been locked in permafrost soils since the last glacial period, to the contemporary carbon cycle. The potential remineralisation of organic carbon to greenhouse gases can contribute to further climate warming. Particulate organic carbon (POC) in the Kolyma River is older than dissolved organic carbon (DOC) thus serves as a good tracer for abrupt permafrost thaw (i.e. river bank erosion and thermokarst) that dominantly releases old POC. While dissolved organic carbon (DOC) mobilised from the old Yedoma outcrops on the banks of the Kolyma River is shown to be highly labile, vulnerability of POC to biodegradation is not yet known. In this study we aim to constrain degradation rates for POC in the Kolyma River. To capture seasonal variability of the POC pool and its degradation rate the incubation was conducted both during the spring ... : EGUsphere ...