Monday, November 13, 2006
47-1
Effect of Application of Composted Swine Manure on Nitrous Oxide Emissions from Agricultural Soils.
Kumudinie Kariyapperuma A.1, A. Furon1, C. Wagner-Riddle2, R. Fleming3, D.G. Louttit2, and M. MacAlpine4. (1) Univ. of Guelph, Dept. Land Resource Sc, Richards Bldg, Guelph, ON N1G 2W1, Canada, (2) Univ of Guelph, Dept. Land Resource Sc, Richards Bldg, Guelph, ON N1G 2W1, Canada, (3) Ridgetown Campus, Univ of Guelph, Ridgetown, ON N0P 2C0, Canada, (4) Ridgetown Campus, Univ of Guelph, Ridgetown, ON N0P 2C0, Canada
Livestock industry is one of the significant sources of agricultural greenhouse gas emissions. The current estimate of global nitrous oxide (N2O) emissions from this source is 2.1Tg of N2O-N per year. Aerobic composting of manure before storage is believed to have potential for mitigating the release of greenhouse gases, but N2O emissions from soils after field application of composted swine manure have not been well quantified. A field experiment was conducted at the Arkell Research Farm, Ontario, Canada from November 2004 to June 2005 to quantify N2O emissions after field application of liquid swine manure and composted swine manure. Treatments were no manure (control), composted swine manure (NH4+-N 80 mg/kg, dry matter 17%) and liquid swine manure (NH4+-N 1424 mg/kg, dry matter 1%). Application of composted manure and liquid manure was carried out in fall/2004 at a rate of 70 kg of total N/ha followed by chisel ploughing (80% stubble left on the field). Before corn planting in 2005, all plots were fertilized with 80 kg of total N/ha. Emissions of N2O from the system were monitored using Tunable Diode Laser Gas Analyser (TDLGA), which measured the mean concentration on an hourly basis. Vertical fluxes of N2O were calculated with the flux gradient method, using sonic and cup anemometer data. All plots showed a significant increase in emissions of N2O (31 – 157 ng/m2/s) during spring thaw period (Day 85 – 95). The average N2O emission from liquid manure-applied plot was 29.1 ± 3.20 ng/m2/s while the emission from compost-applied plot was 13.8 ± 2.93 ng/m2/s for the period of day 36 to 161 in 2005. Application of manure has been repeated in fall/2005 at the rate of 70 kg total N/ha and the measurement of N2O is on going.