Greenhouse gas emissions from an irrigated crop rotation utilizing dairy manure

Leytem, A.B. and Moore, Amber and Dungan, R.S. (2019) Greenhouse gas emissions from an irrigated crop rotation utilizing dairy manure. Soil Science Society of America Journal. 83:137-152. 21 February 2019.

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Abstract

Information on greenhouse gas (GHG) emissions from manure application in cropping systems of the irrigated mountain west region is needed. The effects of manure application rate and timing on GHG emissions from a four-year commercial rotation under sprinkler irrigation was investigated. Treatments included dry manure rates of 52 or 18 Mg/ha applied annually or 36 Mg/ha applied biennially as well as fertilizer and control treatments. Cumulative losses of N2O-N over the rotation ranged from 1.4 to 8.4 kg/ha with the 52 Mg/ha manure application losing the greatest amount of N2O-N. Calculated emission factors indicated that 0.13 to 0.24% of total N applied was lost as N2O-N, much less than the emission factor of 1% used by the IPCC. Cumulative CO2-C losses were greater in the manure treatments compared to the fertilizer and controls, with approximately 7% of carbon added lost as CO2-C. These soils acted as a sink for CH4-C with average fluxes ranging from -0.1 to -0.3 kg/ha. Maximum N2O-N flux levels occurred at soil moisture contents ranging from 0.3 to 0.4 m3/m3 and temperature near 25 °C, while CO2-C emissions occurred over broader soil moisture and temperature conditions. The overall global warming potential (GWP) associated with manure application indicated that the manure treatments had a net negative GWP while fertilizer treatment was near neutral. A better understanding of regional soil and climatic conditions that affect GHG emissions will enable the development of emission factors more appropriate for use in GHG inventory efforts.

Item Type:	Article
NWISRL Publication Number:	1649
Subjects:	Air Quality > Air Emissions Air Quality > Air Emissions > Manure Management
Depositing User:	Users 6 not found.
Date Deposited:	17 May 2019 19:42
Last Modified:	17 May 2019 19:42
Item ID:	1693
URI:	https://eprints.nwisrl.ars.usda.gov/id/eprint/1693