Title Nitrous oxide production in boreal soils with variable organic matter content at low temperature-snow manipulation experiment
Author Maljanen, M.; Virkajarvi, P.Y.; Hytonen, J.; Oquist, M.; Sparrman, T.; Martikainen, P.J.
Author Affil Maljanen, M., University of Kuopio, Department of Environmental Science, Kuopio, Finland. Other: Agrifood Research Finland, Finland; Finnish Forest Research Institute, Finland; Swedish University of Agricultural Sciences, Sweden; Umea University, Sweden
Source Biogeosciences, 6(11), p.2461-2473, . Publisher: Copernicus GmbH on behalf of the European Union, Katlenburg-Lindau, International. ISSN: 1726- 4170
Publication Date 2009
Notes In English. Part of special issue no. 59, Greenhouse gas exchanges, carbon balances and processes of northern ecosystems, edited by Lindroth, A., et al, http://www.biogeosciences.net/special_issue59.h tml; published in Biogeosciences Discussions: 27 May 2009, http://www.biogeosciences- discuss.net/6/5305/2009/bgd-6-5305-2009.html; accessed in Feb., 2011; abstract: doi:10.5194/bg-6-2461-2009. 44 refs. GeoRef Acc. No: 308336
Index Terms ecosystems; experimentation; freezing; geochemistry; global change; global warming; ice; moisture; peat; sediments; snow; soils; soil chemistry; soil freezing; soil temperature; soil tests; statistical analysis; temperature; thawing; Finland-- Eastern Finland Province; Finland--Kannus; Finland--Maaninka; Finland--Western Finland Province; boreal environment; carbon dioxide; clastic sediments; denitrification; Eastern Finland Province; Europe; experimental studies; field studies; Finland; greenhouse gases; Kannus Finland; laboratory studies; Maaninka Finland; nitrates; nitrous oxide; One-Way Anova; organic compounds; sand; Scandinavia; seasonal variations; soil gases; terrestrial environment; Western Europe; Western Finland Province
Abstract Agricultural soils are the most important sources for the greenhouse gas nitrous oxide (N2O), which is produced and emitted from soils also at low temperatures. The processes behind emissions at low temperatures are still poorly known. Snow is a good insulator and it keeps soil temperature rather constant. To simulate the effects of a reduction in snow depth on N2O emission in warming climate, snow pack was removed from experimental plots on three different agricultural soils (sand, mull, peat). Removal of snow lowered soil temperature and increased the extent and duration of soil frost in sand and mull soils. This led to enhanced N2O emissions during freezing and thawing events. The cumulative emissions during the first year when snow was removed over the whole winter were 0.25, 0.66 and 3.0 g N2O-N m-2 yr-1 in control plots of sand, mull and peat soils, respectively. In the treatment plots, without snow cover, the respective cumulative emissions were 0.37, 1.3 and 3.3 g N2O-N m-2 yr-1. Shorter snow manipulation during the second year did not increase the annual emissions. Only 20% of the N2O emission occurred during the growing season. Thus, these results highlight the importance of the winter season for this exchange and that the year-round measurements of annual N2O emissions from boreal soils are integral for estimating their N2O source strength. N2O accumulated in the frozen soil during winter and the soil N2O concentration correlated with the depth of frost but not with the winter N2O emission rates per se. Also laboratory incubations of soil samples showed high production rates of N2O at temperatures below 0C, especially in the sand and peat soils.
URL http://www.biogeosciences.net/6/2461/2009/bg-6-2461-2009.pdf
Publication Type journal article
Record ID 65004966