Minimizing yield-based nitrous oxide emission factors on an intensively managed grassland in the Netherlands by fertilizer selection. (S03-kuikman788991-poster)
Authors:
J. Dolfing* - Alterra, Wageningen UR, Netherlands J.W. Van - Groenigen
P.J. Kuikman - Alterra, Wageningen UR, Netherlands
Abstract:
Future legislation to reduce greenhouse gas emissions from agricultural fields may have considerable implications for farmers, since many management decisions will affect emissions of N2O, CH4 and CO2. Prices for emissions are currently ~$ 10 per ton CO2 equivalents, and the global warming potential of N2O is approximately 310 times higher than CO2. Expressing N2O emission factors on a basis of N uptake in the crop, rather than on the amount of N applied, makes it possible to offset the costs of increased N2O emissions to the gains of increased yields. We measured N2O emissions over two years at an intensively managed grassland site in The Netherlands. Emissions were measured from fertilization treatments with (combinations of) ammonium sulfate, ammonium nitrate and manure. Grass yields and cumulative N2O fluxes varied between years and between treatments. In 2001 there was a clear correlation between the amount of N added and the amount of N2O emitted. In 2002 such a correlation (if any) was less distinct. In both years the N2O emission was ~1.9 g N2O-N / kg N uptake in grass produced without animal manure versus ~3.5 g/kg in grass produced with animal manure. The lowest uptake-based emission factors (~1.2 g N2O-N / kg N) were found for Calcium Ammonium Nitrate, at 35 % of the recommended application rate.
Speaker Information: Jan Dolfing, Alterra, Wageningen UR, Netherlands, J.DolfingAlterraP.O. Box 47, Wageningen, 6700 AA; Phone: +31 317 474334; E-mail: [email protected]
Session Information: Monday, November 3, 2003, 4:00 PM-6:00 PM Presentation Start: 4:00 PM (Poster Board Number: 1307) Keywords: climate change; nitrous oxide; grassland; fertilizer
