Project description DEENESFRITPL The importance of thermokarst-affected permafrost soils in the global nitrogen cycle Global changes are modifying the Arctic regions' climate, where temperatures have risen faster than anywhere else on Earth. These regions store vast amounts of soil organic matter (SOM) in permafrost soils that rapidly release nutrients and greenhouse gases when they thaw. The thawing yields thermokarst processes that occur abruptly, leading to ground surface collapse and to the development of ecosystems (ponds and lakes) where anaerobic environments enhance microbial activity. With Arctic warming, permafrost thawing and thermokarst processes will increase, releasing soluble nitrogen (N) into the environment, thus enhancing microbial decomposition of SOM. The EU-funded NITROKARST project will explore the underlying mechanisms of the N cycle in thermokarst systems, examining how microbial pathways promote N transformation and how thawing controls the operation of these processes. Show the project objective Hide the project objective Objective Global change leads modifications in climate on Arctic regions, where temperatures have risen faster than in any other region on Earth. Those regions store vast amounts of soil organic matter (SOM) in permafrost soils, covering ~25% of terrestrial surface. When they thaw, it leads to rapid release of nutrients and greenhouse gases (GHG). So far, many studies have addressed the importance of permafrost thaw in the carbon cycle. However, little attention has been paid to the nitrogen (N) cycle, despite nitrous oxide (N2O) is a powerful GHG, an ozone-depleting agent and may create an unaccounted permafrost-climate feedback.Permafrost with low ice content suffers a gradual top-down thawing process during seasonal freeze-thaw period. However, thaw of ice-rich permafrost results in thermokarst processes, which occur abruptly and lead to ground surface collapse. Its widespread occurrence affects large areas (~40% of the northern permafrost region) contributing to develop ecosystems like ponds and lakes. In such ecosystems, the presence of anaerobic environments enhances microbial activity. As Arctic warms, permafrost thaw and thermokarst processes will increase, releasing soluble N into the environment and enhancing microbial decomposition of SOM.Hence, mineralization, nitrification and denitrification rates are expected to increase, and thus, N2O emissions to the atmosphere. Unfortunately, the impact of permafrost thaw on N cycling remains understudied, and almost unknown in thermokarst systems. NITROKARST will explore the underlying mechanisms of the N cycle in thermokarst systems, looking at how microbial pathways promote N transformation and how thawing controls the operation of these processes. N cycling will be studied along a thermokarst transect by combining isotope tracing, metagenomics and microcosm incubations. This multidisciplinary approach will increase our knowledge about the importance of thermokarst-affected permafrost soils in the global N cycle. Fields of science natural sciencesbiological sciencesecologyecosystems Keywords Nitrogen cycle Nitrous oxide Permafrost thaw Thermokarst Microbial metabolism Metagenomics Programme(s) H2020-EU.1.3. - EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions Main Programme H2020-EU.1.3.2. - Nurturing excellence by means of cross-border and cross-sector mobility Topic(s) MSCA-IF-2020 - Individual Fellowships Call for proposal H2020-MSCA-IF-2020 See other projects for this call Funding Scheme MSCA-IF - Marie Skłodowska-Curie Individual Fellowships (IF) Coordinator UNIVERSITAT WIEN Net EU contribution € 174 167,04 Address UNIVERSITATSRING 1 1010 Wien Austria See on map Region Ostösterreich Wien Wien Activity type Higher or Secondary Education Establishments Links Contact the organisation Opens in new window Website Opens in new window Participation in EU R&I programmes Opens in new window HORIZON collaboration network Opens in new window Total cost € 174 167,04
