Details zur Publikation |
| Kategorie | Textpublikation |
| Referenztyp | Zeitschriften |
| DOI | 10.1007/s10533-008-9262-z |
| Volltext | Shareable Link |
| Titel (primär) | Denitrification and nitrous oxide effluxes in boreal, eutrophic river sediments under increasing nitrate load: a laboratory microcosm study |
| Autor | Silvennoinen, H.; Liikanen, A.; Torssonen, J.; Stange, C.F.; Martikainen, P.J. |
| Quelle | Biogeochemistry |
| Erscheinungsjahr | 2008 |
| Department | BOPHY |
| Band/Volume | 91 |
| Heft | 2-3 |
| Seite von | 105 |
| Seite bis | 116 |
| Sprache | englisch |
| Keywords | Stable isotopes; Eutrophication; NO3- removal; N2O/N-2 ratio; Bothnian Bay; River sediment |
| Abstract | Intact sediment cores from rivers of the Bothnian Bay (Baltic Sea) were studied for denitrification based on benthic fluxes of molecular nitrogen (N-2) and nitrous oxide (N2O) in a temperature controlled continuous water flow laboratory microcosm under 10, 30, 100, and 300 mu M of N-15 enriched nitrate (NO3 (-), similar to 98 at. %). Effluxes of both N-2 and N2O from sediment to the overlying water increased with increasing NO3 (-) load. Although the ratio of N2O to N-2 increased with increasing NO3 (-) load, it remained below 0.04, N-2 always being the main product. At the NO3 (-) concentrations most frequently found in the studied river water (10-100 mu M), up to 8% of the NO3 (-) was removed in denitrification, whereas with the highest concentration (300 mu M), the removal by denitrification was less than 2%. However, overall up to 42% of the NO3 (-) was removed by mechanisms other than denitrification. As the microbial activity was simultaneously enhanced by the NO3 (-) ! load, shown as increased oxygen consumption and dissolved inorganic carbom efflux, it is likely that a majority of the NO3 (-) was assimilated by microbes during their growth. The N-15 content in ammonium (NH4 (+)) in the efflux was low, suggesting that reduction of NO3 (-) to NH4 (+) was not the reason for the NO3 (-) removal. This study provides the first published information on denitrification and N2O fluxes and their regulation by NO3 (-) load in eutrophic high latitude rivers. |
| dauerhafte UFZ-Verlinkung | https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=1468 |
| Silvennoinen, H., Liikanen, A., Torssonen, J., Stange, C.F., Martikainen, P.J. (2008): Denitrification and nitrous oxide effluxes in boreal, eutrophic river sediments under increasing nitrate load: a laboratory microcosm study Biogeochemistry 91 (2-3), 105 - 116 10.1007/s10533-008-9262-z |
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