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United States Department of Agriculture

Agricultural Research Service

Research Project: GRACENET: AN ASSESSMENT OF SOIL CARBON SEQUESTRATION AND GREENHOUSE GAS MITIGATION BY AGRICULTURAL MANAGEMENT

Location: Soil Plant Nutrient Research (SPNR)

2008 Annual Report


1a.Objectives (from AD-416)
1. Evaluate the soil C status and direction of change of soil C in existing typical and alternative agricultural systems.

2. Determine net GHG emission (CO2, CH4 and N2O) of current agricultural systems in existing typical and alternative agricultural systems.

3. Determine the environmental effects (water, air and soil quality) of the new agricultural systems developed to reduce GHG emission and increase soil C storage.

Note: All participating units will address Objective 1. Those units with the capacity to measure trace gases will also address Objective 2. While those with the capacity to measure other environmental parameters will also address Objective 3. Scenarios 1 and 2 correspond to Objective 1, Scenario 3 corresponds to Objective 2 and Scenario 4 corresponds to Objective 3.


1b.Approach (from AD-416)
The GRACEnet experimental concept is based on four location-specific scenarios or treatments: What is the C accumulation rate under typical agricultural management practices? These business as usual systems should be economically viable or at least used by the majority of producers that are able to continue in production agriculture in that area of the country. Each unit will determine the number of sub-treatments it will research, since there may be many variations on typical practices within a geographic area. Maximizing C sequestration rate. What has to be done to achieve the highest rate of sequestration in that production system? These treatments may be either economically feasible or technically feasible. The only constraint is that they remain in a agriculturally feasible production system. Each unit will determine the number of sub treatments it will research, since there will be many variations on practices to potentially maximize C sequestration.

Minimizing net GHG emission: This system differs from #2 because N2O and CH4 emission must also be considered. How does this management scenario compare with #2? What is the sequestration rate and net GHG balance when all GHG emission are considered? Agriculture is the main source of N2O and CH4 to the atmosphere. Therefore, data will be collected by the units that have the capability and capacity to determine N2O and CH4 on the treatments under study in scenarios 1 and 2. Practices will be developed to decrease the emission of N2O and CH4. Each unit that addresses this scenario will determine the number of sub treatments it will research, since there will be many variations on practices to potentially maximize C sequestration.

Maximizing environmental benefits: Carbon sequestration may well become part of a larger conservation benefit package. Land managers and policy makers will be interested in tradeoffs among management options. With careful management, how can soil C sequestration and GHG emission be balanced with water quality, air quality, and soil quality goals? Units capable of evaluating environmental benefits and C sequestration will be encouraged both to study the individual issue or issues that they can address (water quality, air quality, or soil quality goals) and to collect data that may contribute information that is consistent with the needs of the ‘larger conservation benefit package’ that may be implemented by USDA or other action agencies.

Particpant CRIS #'s: 1265-21660-002-00D; 1275-11210-001-00D; 1265-12130-002-00D; 3625-11000-004-00D; 3645-11000-003-00D; 3640-12000-007-00D; 3602-12220-006-00D; 6420-12610-003-00D; 6420-11120-005-00D; 1915-62660-001-00D; 1902-13000-010-00D; 5407-12130-006-00D;1935-12000-010-00D; 5447-12620-002-00D; 5402-66000-005-00D;5402-11000-008-00L; 5409-11000-003-00D; 5440-12210-050-00D; 5445-11120-001-00D; 5436-13210-004-00D; 1932-12000-004-00D; 5358-21410-002-00D; 5368-12000-008-00D; 5354-21660-001-00D; 5356-12000-009-00D; 5247-11000-008-00D; 5348-11120-003-00D; 5342-13610-007-00D; 6615-11000-007-00D; 6657-12000-005-00D; 6602-13000-024-00D; 6612-11120-003-00D; 6208-12000-009-00D; 6206-11120-004-00D.


3.Progress Report

GRACEnet formalized: The Greenhouse gas Reduction through Carbon Enhancement network, which represents 60-plus ARS scientists at 30 locations across the United States following the same set of protocols, was formally recognized as a CLR (Cross Location Research project). The work plan, milestones and products were finalized during a planning workshop held at Fort Collins (Oct 2005). This network of research locations, works together to better characterize management practices that would limit greenhouse gas emissions from agriculture. Information from this network approach will benefit policy makers, farmers, and all of society by maintaining a food production system that has less impact on the global atmosphere. This research contributes directly to the ARS Global Change Program National Program (NP-204); specifically contributing to the Carbon Cycle and Carbon Storage and Trace Gases Problem Areas and contributes to Soil Resource Management National Program (NP-202) Problem Area 3 (Soil Carbon).

NOTE: Scientific Publications: Log 115: Thirty four peer-reviewed journal, proceedings, and book chapters are reported by GRACEnet scientists during the 2007-2008 reporting period. Various additional popular press and other articles were also released about GRACEnet and GRACEnet related activities. Publications are reported in ARIS by each of the individual locations under their own base CRIS’s rather than under this CRL CRIS.


4.Accomplishments
1. Final draft of the U.S. Agriculture and Forestry Greenhouse Gas Inventory:1990-2005. Global Change Program Office, Office of the Chief Economist, U.S. Department of Agriculture. Technical Bulletin No. 1921. 159 pp. August, 2008 submitted to the USDA Global Change Program Office and for printing by the GPO. This 112 page report and the included appendices inventories the emissions of the three most important long-lived greenhouse gases (GHG) have increased measurably over the past two centuries. Carbon dioxide (CO2), methane (CH4), and nitrous oxide (N2O) concentrations in the atmosphere have increased by approximately 35%, 155%, and 18%, respectively, since 1750. In the U.S., agriculture accounted for close to 7% of total GHG emissions (7260 Tg CO2 eq.) in 2005. Livestock, poultry, and crop production contributed a total of 481 Tg CO2 eq. to the atmosphere in 2005. This total includes an offset from agricultural soil carbon sequestration of roughly 32 Tg CO2 eq. The primary agricultural sources are N2O emissions from cropped and grazed soils (263 Tg CO2 eq.), CH4 emissions from enteric fermentation (112 Tg CO2 eq.), and CH4 emissions from managed livestock waste (41 Tg CO2 eq.). Forests in the United States contributed a net reduction in atmospheric GHG of approximately 787 Tg CO2 eq. in 2005, which offset total U.S. GHG emissions by approximately 11%. In aggregate, the U.S. agricultural sector (including GHG sources for crop, poultry, and livestock production and GHG sinks for forests and wood products) was estimated to be a net sink of 306 Tg CO2 eq. in 2005.


5.Significant Activities that Support Special Target Populations
none.


Last Modified: 10/1/2014
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