@article{Maljanen_Virkajärvi_Martikainen_2012, title={Dairy cow excreta patches change the boreal grass swards from sink to source of methane}, volume={21}, url={https://journal.fi/afs/article/view/5016}, DOI={10.23986/afsci.5016}, abstractNote={<p>We studied methane (CH<sub>4</sub>) flux rates from experimental excreta patches on a dairy pasture with a chamber technique during snow free seasons and with a gas gradient technique during winter from timothy-meadow fescue sward with mineral N fertilization (220 kg ha<sup>-1</sup>) and from grass-white clover mixture without fertilization. The dung and urine patches were applied in June or August two consecutive grazing seasons and the measurements were carried out for a year following each application. There were no significant differences in CH<sub>4</sub> fluxes between plant species and emissions originated mainly from the fresh dung pats. The average annual CH<sub>4</sub> fluxes from the control sites without excreta were -0.60±0.1 and with the excreta 0.47±0.3 kg CH<sub>4</sub> ha<sup>-1</sup>. Thus, excreta originating from dairy cows can turn boreal swards from weak sinks to small sources of CH<sub>4</sub>. However, these emissions are only 0.2% of the total CH<sub>4</sub> emissions from a dairy cow.</p>}, number={2}, journal={Agricultural and Food Science}, author={Maljanen, Marja Elisa and Virkajärvi, Perttu and Martikainen, Pertti J.}, year={2012}, month={Jun.}, pages={91–99} }