Reference
- Borken, W., Davidson, E. A., Savage, K., Sundquist, E. T. and Steudler, P. 2006. Effect of summer throughfall exclusion, summer drought, and winter snow cover on methane fluxes in a temperate forest soil. Soil Biol. Biochem. 38, 1388–1395.
- Christensen, S. and Tiedje, J. M. 1990. Brief and vigorous N20 production by soil at spring thaw. J. Soil Sci. 41, 1–4.
- Drebs, A., Norlund, A., Karlsson, P., Helminen, J. and Rissanen, P. 2002. Climatological Statistics of Finland 1971-2000, No. 2002:1, Finnish Meteorological Institute, Edita Prima Oy, Helsinki, 99 p.
- Edwards, A. C. and Cresser, M. S. 1992. Freezing and its effects on chemical and biological properties of soil. Adv. Soil Sci., 18, 59–79.
- Fawcett, J. K. and Scott, J. E. 1960. A Rapid and precise method for the determination of urea. J. Clin. Path. 13, 156–159.
- Gandahl, R. 1957. Bestämning av tjälgräns i mark med enkel typ av tjälgränsmätare. Grundförböttring 10, 7-19. (In Swedish)
- Goodroad, L. L. and Keeney, D. R. 1984. Nitrous oxide emission from soils during thawing. Can. J. Soil Sci. 64, 187–194.
- Groffman, P. M., Hardy, J. P., Scott, N., Fitzhugh, R. D., Driscoll, C. T., and co-authors. 2006. Snow depth, soil freezing and fluxes of carbon dioxide, nitrous oxide and methane in a northern hardwood forest. Global Change Biol. 12, 1748–1760.
- Holtan-Hartwig, L., Dorsch, P. and Bakken, L. R. 2002. Low temperature control of soil denitrifying communities: kinetics of N20 production and reduction. Soil Biol. Biochem. 34, 1797–1806.
- Houghton, J. T., Ding, Y., Griggs, D. J., Noguer, M., van der Linden, P. J., and co-authors. 2001. Climate Change 2001: The Scientific Basis. Contribution of Working Group Ito the Third Assessment Report of the Intergovernmental Panel on Climate Change. Cambridge University Press, Cambridge. 881 p.
- Kammann, C., Grandhage, L., Muller, C., Jacobi, S. and Jager, H. J. 1998. Seasonal variability and mitigation options for N20 emissions from differently managed grasslands. Environ. PolluL 102 Si, 179–186.
- Kammann, C., Grandhage, L. and Jager, H. J. 2001. A new sampling technique to monitor concentrations of CH4, N20 and CO2 in air at well-defined depths in soils with varied water potential. Eur J. Soil Sci. 52, 297–303.
- Koponen, H. T., Flojt, L. and Martikainen, P. J. 2004. Nitrous oxide emissions from agricultural soils at low temperatures: a laboratory microcosm study. Soil Biol. Biochem. 36, 757–766.
- Koponen, H. T., Escude Duran, C., Maljanen, M., Hytönen, J. and Martikainen, P. J. 2006a. Temperature responses of NO and N20 emissions from boreal organic soil. Soil Biol. Biochem. 38, 1779–1787.
- Koponen, H. T., Jaakkola, T., Keinänen-Toivola, M. M., Kaipainen, S., Tuomainen, J., and co-authors. 2006b. Microbial communities, biomass and activities in soils as affected by freeze thaw cycles. Soil Biol. Biochem. 38, 1861–1871.
- Maljanen, M., Liikanen, A., Silvola, J. and Martikainen, P. J. 2003a. Nitrous oxide emissions from boreal organic soil under different land-use. Soil Biol. Biochem. 35, 689–700.
- Maljanen, M., Liikanen, A., Silvola, J. and Martikainen, P. J. 2003b. Measuring N20 emissions from organic soils with closed chamber or gas gradient methods. Eur J. Soil Sci. 54, 625–631.
- Mørkved, P. T., Dorsch, P., Henriksen, T. M. and Bakken, L. R. 2006. N20 emissions and product ratios of nitrification and denitrification as affected by freezing and thawing. Soil Biol. Biochem. 38,3411–3420.
- Öquist, M. G., Nilsson, M., Sorensson, E, Kasimir-Klemedtsson, A., Persson, T., and co-authors. 2004. Nitrous oxide production in a forest soil at low temperatures-processes and environmental controls. FEMS Microbiol. EcoL 46,371–378.
- Öquist, M. G., Petrone, K., Nilsson, M., Persson, and Klemedtsson, L. 2007. Nitrification controls N20 production rates in frozen boreal forest soil. Soil Biol. Biochem. 39, 1809–1811.
- Phillips, R. L. 2007. Organic agriculture and nitrous oxide emissions at sub-zero temperatures. J. Environ. Qual. 36, 23–30.
- Regina, K., Syväsalo, E., Harmukkala, A. and Esala, M. 2004. Fluxes of N20 from farmed peat soils in Finland. Eur J. Soil Sci. 55, 591–599.
- Röver, M., Heinemeyer, O. and Kaiser, E. A. 1998. Microbial induced nitrous oxide emissions from an arable soil during winter. Soil Biol. Biochem. 30, 1859–1865.
- Schmidt, S. K. and Lipson, D. A. 2004. Microbial growth under the snow: Implications for nutrient and allelochemical availability in temperate soils. Plant Soil 259, 1–7.
- Schürmann, A., Mohn, J. and Bachofen, R. 2002. N20 emissions from snow-covered soils in the Swiss Alps. Tellus 54B, 134–142.
- Sharma, S., Szele, Z., Schilling, R., Munch, J. C. and Schloter, M. 2006. Influence of freeze-thaw stress on the structure and function of microbial communities and denitrifying populations in soil. AppL Environ. Microb. 72, 2184–2154.
- Sommerfeld, R. A., Mosier, A. R. and Musselman, R. C. 1993. CO2, CH4 and N20 flux through a Wyoming snowpack and implications for global budgets. Nature 361, 140–142.
- Sparrman, T., Oquist, M., Klemedtsson, L., Schleucher, J. and Nilsson, M. 2004. Quantifying unfrozen water in frozen soil by high-field 211 NMR. Environ. Sci. & TechnoL 38, 5420–5425.
- Syväsalo, E., Regina, K., Turtola, E., Lemola, R. and Esala, M. 2006. Fluxes of nitrous oxide and methane, and nitrogen leaching from organically and conventionally cultivated sandy soil in western Finland. Agricult. Ecosys. Environ. 113, 342–348.
- Teepe, R., Brumme, R. and Beese, E 2000. Nitrous oxide from frozen soils under agricultural, fallow and forest. Soil Biol. Biochem. 32, 1807–1810.
- Teepe, R., Brumme, R. and Beese, E 2001. Nitrous oxide emissions from soil during freezing and thawing periods. Soil Biol. Biochem. 33, 1269–1275.
- van Bochove, E., Jones, H. G., Bertrand, N. and Prevost, D. 2000. Winter fluxes of greenhouse gases from snow-covered agricultural soil: intra-annual and interarmual variations. Global Biogeochem. Cy. 14, 113–125.
- van Bochove, E., Theriault, G. and Rochette, P. 2001. Thick ice layers in snow and frozen soil affecting gas emissions from agricultural soils during winter. J. Geophys. Res. 106, 23061–23071.
- Virkajärvi, P. and Järvenranta, K. 2001. Leaf dynamics of timothy and meadow fescue under Nordic conditions. Grass Forage Sci. 56, 294–304.