Tuesday, November 6, 2007
222-17
Simultaneous Measurements of Ammonia, Nitrous Oxide and Odour Emissions from Surface Applied Swine Manure.
Erin Smith, PO Box 550 20 Tower Road, Nova Scotia, Dept. of Agr. & Mktg., Nova Scotia Agricultural College, Department of Agriculture & Marketing, Truro, NS B2N 5E3, CANADA, R. Gordon, Nova Scotia Agricultural College, Truro, NS B2N 5E3, Canada, Charles Bourque, Forestry and Environmental Management, University of New Brunswick, P.O. Box 4440, Fredericton, NB E3B 5A3, Canada, and Allan J. Campbell, Agriculture and Agri-Food Canada, 440 University Avenue, Charlottetown, PE C1A 4N6, Canada.
Swine manure when applied to cropland has the potential to generate ammonia (NH3), nitrous oxide (N2O) and odour. Limited studies have simultaneously examined their emissions in support of development of improved management strategies. Field trials were conducted to examine NH3, N2O and odour emissions from both surface applied liquid and solid swine manure. Swine manure was surface applied to an acidic grain stubble field. The effect of manure type (liquid and solid), application rate (1x: 30,000-36,000 L ha-1, 2x: 60,000-72,000 L ha-1 and 5x: 180,000 L ha-1) and rainfall (50-150 mm) before and after manure application were examined. Compared to solid manure, liquid manure had 13% less odour emissions and 32% reduced NH3 emissions. Increasing manure application rates enhanced both odour and NH3 emissions and applying manure before a rainfall event reduced odour, as well as NH3 by 7% and 36%, respectively. Ammonia and odour emissions were similar in their dependence on atmospheric conditions with increased emissions at higher air and soil temperatures, net radiation, VPD and windspeed. Nitrous oxide emissions from all trials were low in magnitude and dependence, suggesting that management strategies to reduce both odour and NH3 were not enhancing N2O emissions when applied to an acidic soil consisting of low soil NO3--N. More effort should therefore be placed on reducing overall NH3 and odour emissions.
Keywords: ammonia, nitrous oxide, odour, swine manure, management strategies