title: Soil greenhouse gas emissions affected by irrigation, tillage, crop rotation, and nitrogen fertilization.
abstract: Management practices, such as irrigation, tillage, cropping system, and N fertilization, may influence soil greenhouse gas (GHG) emissions. We quantified the effects of irrigation, tillage, crop rotation, and N fertilization on soil CO, NO, and CH emissions from March to November, 2008 to 2011 in a Lihen sandy loam in western North Dakota. Treatments were two irrigation practices (irrigated and nonirrigated) and five cropping systems (conventional-tilled malt barley [ L.] with N fertilizer [CT-N], conventional-tilled malt barley with no N fertilizer [CT-C], no-tilled malt barley-pea [ L.] with N fertilizer [NT-PN], no-tilled malt barley with N fertilizer [NT-N], and no-tilled malt barley with no N fertilizer [NT-C]). The GHG fluxes varied with date of sampling and peaked immediately after precipitation, irrigation, and/or N fertilization events during increased soil temperature. Both CO and NO fluxes were greater in CT-N under the irrigated condition, but CH uptake was greater in NT-PN under the nonirrigated condition than in other treatments. Although tillage and N fertilization increased CO and NO fluxes by 8 to 30%, N fertilization and monocropping reduced CH uptake by 39 to 40%. The NT-PN, regardless of irrigation, might mitigate GHG emissions by reducing CO and NO emissions and increasing CH uptake relative to other treatments. To account for global warming potential for such a practice, information on productions associated with CO emissions along with NO and CH fluxes is needed.
authors.affiliation: USDA-ARS, Sidney, MT, USA. Upendra.sainju@ars.usda.gov
authors.forename: Upendra M
authors.initials: UM
authors.lastname: Sainju
authors.forename: William B
authors.initials: WB
authors.lastname: Stevens
authors.forename: Thecan
authors.initials: T
authors.lastname: Caesar-Tonthat
authors.forename: Mark A
authors.initials: MA
authors.lastname: Liebig
mesh_terms: D057914:Agricultural Irrigation; D000383:Agriculture / Q000379:methods*; D002245:Carbon Dioxide / Q000737:chemistry; D003247:Conservation of Natural Resources; D018556:Crops, Agricultural; D004784:Environmental Monitoring; D005308:Fertilizers / Q000032:analysis; D005740:Gases / Q000737:chemistry*; D017752:Greenhouse Effect; D008697:Methane / Q000737:chemistry; D009584:Nitrogen / Q000737:chemistry*; D009609:Nitrous Oxide / Q000737:chemistry; D012987:Soil / Q000737:chemistry*; D013696:Temperature; D013997:Time Factors
chemical_list: D005308:Fertilizers; D005740:Gases; D012987:Soil; D002245:Carbon Dioxide; D009609:Nitrous Oxide; D009584:Nitrogen; D008697:Methane