Location: Soil Dynamics Research2010 Annual Report
1a. Objectives (from AD-416)
The fertilizer industry and the USDA-Agricultural Research Service's (USDA-ARS) GRACEnet project need scientifically sound N2O emissions data from field research plots treated with various N sources across the U.S. The USDA-ARS GRACEnet cross location project has (1) a research network in place; (2) established cross location protocols for greenhouse gas sampling; (3) the facilities and personnel; and (4) the initial instrumentation required to expand its collection of this type of data. GRACEnet objective 2 includes the collection of CO2, N2O and CH4 greenhouse gas data, in addition to soil carbon sequestration. This research project will evaluate the effects of controlled release and stabilized nitrogen sources on nitrous oxide emissions in rainfed and irrigated cropping systems at several ARS research locations compared with the commonly used urea and urea-ammonium nitrate fertilizer sources.
1b. Approach (from AD-416)
Nitrogen source studies will be conducted at five ARS locations (Fort Collins, CO; Ames, IA; St. Paul, MN; Pullman, WA; and Auburn, AL) to collect greenhouse gas emissions data from corn, cotton, wheat, and potato cropping systems (varies with location). Several N fertilizer sources (a controlled release polymer-coated urea (ESN); a stabilized urea source, SuperU or UAN treated with AgrotainPlus; UAN and/or Urea as conventional sources) will be applied as a minimum to a cropping system at each location. Except for the irrigated Fort Collins site and one irrigated site at St. Paul, all sites are rainfed cropping systems, with either conventional tillage or no-tillage management practices, or both. Nitrogen rates at each location will include at least a near optimal N rate (for greenhouse gas data collection) for the crop and cropping system. The N sources will be applied using normal farming practices at each location. Nitrous oxide emissions (and possibly CO2 and CH4 emissions) from each N source treatment and a check (zero fertilizer N applied) treatment will be monitored several times each week during the growing season. Methods used for greenhouse gas measurements will follow those established for the ARS GRACEnet program. Crop yield data, needed soil water and temperature data, and other necessary data needed to interpret the greenhouse gas emissions results will be collected. A scientifically sound experimental design with a minimum of 3 replications will be used at each location. 5402-11000-008-00L: GRACEnet: An Assessment of Soil Carbon Sequestration and Greenhouse Gas Mitigation by Agricultural Management Cross Location Participants listed under 5402-11000-008-00L/411610: 3625-11000-004-00D/409178: Trace Gas Exchanges in Midwest Cropping Systems Dr. Jerry Hatfield: National Soil Tilth Research Laboratory (Ames, Iowa) 3640-12000-007-00D/410684: Farming Practices for the Northern Corn Belt to Protect Soil Resources, Support Biofuel Production and Reduce Global Warming Potential Dr. Rod Venterea: Soil and Water Management Research (St. Paul, MN) 5348-11120-004-00D/411380: Soil Conservation Systems for Sustainability of Pacific Northwest Agriculture Dr. Jeff Smith: Land Management and Water Conservation Research (Pullman, WA) 5402-12130-008-00D/410759: Improving Soil and Nutrient Management Systems for Sustained Productivity and Environmental Quality Dr. Ardell Halvorson: Soil, Plant, Nutrient Research (Fort Collins, CO) 6420-12610-003-00D/410823: Conservation Systems Research for Improving Environmental Quality and Producer Profitability Dr. Allen Torbert: Soil Dynamics Research (Auburn, AL)
3. Progress Report
More information is needed on the effects of nitrogen (N) fertilizer sources on their contribution to greenhouse gas emissions from an irrigated cotton cropping systems. Thus a study was initiated in 2008 to evaluate the impact that controlled release and stabilized N fertilizer have on N use efficiency in agricultural systems. This study evaluates the impacts of several N sources (controlled released polymer-coated urea (ESN); a stabilized urea source, Super Urea (U) or Urea-Ammonium Nitrate (UAN) treated with AgrotainPlus; UAN and/ or Urea as conventional sources). In the second year of study (2009), nitrous oxide emissions were evaluated several times throughout the growing season, with methods of analysis performed according to the ARS GRACEnet protocol. This evaluation started on the day of fertilization (mid June) and continued through the growing season until crop harvest. The nitrous oxide loss was compared to crop yield in order to determine any correlation between crop yield and gaseous loss.