Abrupt permafrost collapse enhances organic carbon, CO 2 , nutrient and metal release into surface waters

摘要: Abstract Thawing of frozen peat in discontinuous permafrost zones may significantly modify the environment at local (slumps and engineering damages) global (greenhouse gases regime) scales. We studied aquatic geochemistry CO2, CH4, dissolved organic carbon (DOC), P, Si, colloidal trace metal from hollows, depressions, subsidences soil waters actively thawing zone Western Siberia Lowland (WSL). This site abrupt collapse is dominated by minerotrophic fens located within flat mound bog. The DOC, major concentrations decreased with increase surface area water body, along hydrological continuum (soil water → hollows → depressions subsidences → thaw ponds → thermokarst lakes). Aqueous Ca, Al, Fe, Nd, U were a factor 4 to 10 higher catastrophic thaw compared steady palsa bog that was previously same region. colloids (1 kDa–0.45 μm) formed hot spots strongly enriched trivalent tetravalent hydrolysates relative carbon. Because thickness depth intensifies input inorganic components deep mineral horizons, enriches Al-rich low molecular weight complexes. As result, WSL's composition shift DOM-rich DOM-Fe-rich DOM-Al-rich, release low-soluble river will increase. hypothesize sites thaw, there direct mobilization network (rivers lakes) minimal transformation autochthonous processes, which unlike case thawing. Therefore, change physical factors, such as pathways residence time, given elementary landscape likely control overall impact on-going on both chemistry greenhouse gas pattern territory. For this, high-resolution (