Location: Natural Resource Management Research2011 Annual Report
1a. Objectives (from AD-416)
Objective 1: Determine the environmental and economic impacts of cover crop and cover crop mixtures in semiarid cropping systems. Objective 2: Develop dynamic cropping systems to help meet bio-energy production needs and increase economic returns while enhancing natural resource quality. Objective 3: Develop multiple enterprise systems that integrate crops and livestock to economically optimize the quality and quantity of agricultural products while maintaining or enhancing soil quality indicators.
1b. Approach (from AD-416)
Multiple methodologies will be used depending on the specific objectives because of the complexity of this integrated agricultural systems research project. Objective 1 will use a modified crop matrix where different cover crops are seeded into a common residue to evaluate the above- and below-ground impact of cover crops on subsequent crops. Objective 2 will use economic analysis, and modeling techniques to develop economically feasible management strategies for biofuels and an Eddy Covariance System to measure CO2 flux as a surrogate for environmental impact of biomass crops. Integration of crops and livestock, Objective 3, will compare the performance of livestock when grazing annual crops in the fall to livestock performance when grazing perennial grasses in the fall. In the first 3 objectives, common data collected will include soil properties, biomass accumulation and soil water use. In addition, data on the impact of bio-char will be collected in Objective 2 and livestock production data will be collected in Objective 3. Economic analysis will be conducted as appropriate.
3. Progress Report
Termination of an earmark linked to the Integrated Agricultural Systems for the Northern Great Plain research project resulted in a loss of funding. A new PDRAM was developed and reflected the funding loss by eliminating Sub-objective 2.1 and Objectives 4 and 5 from the project. All milestones relating to these objectives will be eliminated for FY11, 12 and 13. The location hired a Headquarters funded post-doc to evaluate spatial and temporal changes in crop diversity. The location is continuing work on evaluating the use of cover crops and cover-crop mixtures in cropping systems on the Northern Great Plains (Objective 1). An outreach tool, the ‘Cover Crop Chart’ was developed and organizes information about cover crops in an easy to understand chart patterned off the periodic table. Objective 2 focuses on developing dynamic cropping systems to meet bio-energy production needs while maintaining environmental quality and enhancing economic returns. The loss of one key personnel and the termination of earmark funding resulted in the elimination of Sub-Objective 2.1 Determine appropriate bioenergy crops for optimizing biofuel production capacity in conjunction with ecological sustainability. Work is continuing on the remaining objectives. Location scientists are involved with the ARS BioChar working group and also the Renewable Energy Assessment Project (REAP), a multi-location project looking at developing sustainable biomass harvesting rates while maintaining our critical soil resource. Objective 3 retains the locations emphasis on developing integrated crop-livestock production systems. This research requires a long-term commitment and some project aspects have been in place for over ten years. Data collection is continuing and a paper comparing water infiltration rates between integrated crop-livestock systems and grass pastures was published. Objective 4 and 5 were eliminated because of the earmark termination.
1. Water infiltration is maintained in integrated crop-livestock systems. Integrated crop-livestock systems may have significant agronomic and environmental benefits compared with single-enterprise systems; however, livestock in integrated systems may cause soil compaction, thereby decreasing infiltration of water into soil. ARS scientists at Mandan, ND, conducted a long-term field study to quantify differences in soil infiltration rate between perennial grass pastures and pastures comprised of annual forage crops as part of integrated crop-livestock systems. They determined that water infiltration rates were highly variable over time, but not different between the integrated crop-livestock and perennial grass pastures. Thus, water infiltration rate in the integrated crop-livestock system was not compromised by grazing livestock suggesting integrated systems may be better adapted to a more vigorous hydrological cycle from the standpoint of water capture and storage. This feature of integrated systems offers an increased system resiliency and potential adaptation to future climate change.
Schmer, M.R., Mitchell, R., Vogel, K.P., Schacht, L.C., Marx, D.B. 2010. Determining switchgrass biomass supplies for cellulosic biorefineries. Natural Resources Research Update (NRRU). Vol. 2, page 1.