Duration: 10/01/2005 to 09/30/2010

Administrative Advisor(s):

NIFA Reps:

Non-Technical Summary

Statement of Issues and Justification

Dairy and beef production are major contributors to the economy of the US, but increasing costs of production, the decline of real prices towards a world market price, and environmental issues are jeopardizing the long-term sustainability of these farms. This is causing a continuing trend toward larger farms concentrated in certain geographic locations. More efficient, economical, and environmentally sound production systems are needed to maintain a viable agricultural industry. Integrated research and technology transfer programs are needed to help dairy and beef farmers manage their farms in a cost effective and environmentally acceptable manner and to comply with new farming regulations. Integrated crop, pasture, and livestock farms form very complex physical and biological systems. Most research focuses on one or relatively few components of the system, providing a narrow view of the potential effects of strategic production changes and an inadequate assessment of the farm-level issues of environmental impact and profitability. Modeling and computer simulation provide an effective research strategy for integrating component-level effects and interactions to predict farm level or higher outcomes. Recently, attention has focused on animal production systems as non-point sources of pollution affecting the quality of air and water resources. In particular, nitrogen and phosphorus may contaminate water following the application of manure or chemical fertilizer to soils (Morse, 1995). Some nitrogen becomes volatilized as ammonia from manure or soils, and eventually contributes to acid rain that endangers forests and water bodies (Luebs et al., 1973). Some nitrogen may be lost from the farm by conversion to atmospheric N2 or nitrous oxides through denitrification, but the majority is normally lost through the other pathways. Phosphorus largely accumulates on farms, mainly as an accumulation in soil, which in turn contributes to accelerated P runoff and the eutrophication of surface waters. On many farms where manure is applied to soil surfaces without incorporation, such as in no-till or pasture fields, potential runoff loss of P can be substantially elevated because much of the manure P is water soluble and thus susceptible to subsequent loss to the environment (Dou et al., 2000, 2002, 2003). Several technology and incentive programs are aimed at reducing the risk of environmental damage from animal agriculture while maintaining farm productivity. However, in order to better direct these resources, there is a need for routine assessment of which farm management practices are most effective on specific farms. Modeling supported by experimental research provides tools for such assessments. These tools may lead to farm management decision support aids that help producers and their consultants identify the most appropriate strategies for managing nutrients on a farm-by-farm basis. In addition, there is a need to collect and analyze data in the field, so as to identify the most appropriate technology transfer programs to address the problems associated with nutrient pollution in a cost effective manner. Because the environmental impact of a farm management decision depends on farm characteristics (e.g., size, soil type, climate) and other management selections (e.g., crop rotations, tillage practices, manure storage), the only way to calculate the benefit of a farm practice is to model the changes in nutrient flows through the entire system. Development of integrated mathematical models enables calculation of the environmental benefit from one or more management or infrastructure changes in any management subsystem (crops, soils, feed, and animal). The development of such an integrated understanding of the farm nutrient cycle requires participation by scientists in a number of diverse disciplines. The NE-132 project has brought together a broad range of disciplines, which led to the development of quantitative models including the GRAzing Simulation Model (GRASIM: http://danpatch.ecn.purdue.edu/~grasim/grasim.html), the Dairy Forage System Model (DAFOSYM : http://pswmru.arsup.psu.edu/software/dafosym.htm), a second generation model called the Integrated Farm System Model (IFSM: http://pswmru.arsup.psu.edu/software/ifsm.htm), the Dairy Nutrient Planner (DNP: http://library.scc.wa.gov/?viewCat=142), and the Whole Farm Balance Nutrient Education Tool (WFBNET: http://www.puyallup.wsu.edu/dairy/data/joeharrison/software/Dairy%20WFNBET%20ver%204.0%20with%20N%20&%20P%20linked%20protected.xls) and FarmSoft. These models are currently being used as tools to evaluate N and P flows through dairy farm systems by university extension and government regulatory agencies. These models integrate years of collaborative research and enable an enhanced understanding of nutrient flows in the farm system. These models need to be further evaluated, validated with real farm data, and adapted to address the immediate needs in the field across the nation related to nutrient management on dairy and beef farms. In the new project, models that were previously developed will be evaluated under diverse farm conditions to identify improved strategies for management of nutrients on farms. The collaborative modeling effort of the group has been critical in identifying knowledge gaps in our understanding of N and P flows in ruminant animal/cropping systems. The models have also helped identify directions for future field/lab research. The broad and diverse research background and expertise of the group has been and will continue to be integrated by the modeling effort. To advance whole-farm model evaluation and application, a coordinated effort is needed at several levels. First, field studies of nutrient dynamics and cropping systems are needed to calibrate predictions for different geographic locations and to evaluate model components. Second, model refinements and software development are needed to enable use of the models on individual farms throughout the U.S. Third, model prediction capacity must be expanded to more accurately partition nutrient losses into those from volatilization, leaching, runoff and denitrification, and consequences of alternative feeding or crop management systems must be expanded. Finally, models must be applied to planning of dairy and beef production systems to reduce or eliminate problems associated with nutrient management and profitability.

Related, Current and Previous Work

The proposed work will build upon and integrate research in several disciplines to make maximal use of previous research. Major areas include crop growth, crop conservation, animal nutrient utilization, manure handling, pasture and grazing, and systems analysis of dairy and beef farms. Each of these areas is addressed in the attachment Related.doc.

Objectives

1. Enhance cropping, grazing, and feeding management systems to improve animal nutrient utilization and reduce nutrient excretion. . (Muck, ARS,WI; Fick, Cornelll, Dou, UPenn; Kohn, UMD; Knowlton, VaTech; Harrison, WA;Combs, WI; Mohtahr, Purdue; Rotz, ARS,PA; Sanderson, ARS;Felton, Wva). Additional details provided in the objectives.doc attachment.
   
2. Evaluate and develop efficient animal, manure, and cropping systems for reduced nutrient flow, cycling, transformation and loss to the environment. (Rotz, ARS,Pa; Herbert, UMass, Dou, UPenn,;Miller, UT; Harrison, WA; Powell, WI; Moreira, LA; Erickson, NE; Knowlton, VaTech). Additional details provided in the objectives.doc attachment.
   
3. Refine, evaluate, and apply integrated quantitative models of dairy and beef farms to predict profitability and nutrient losses to the environment. (Rotz, ARS, PA;Rayburn, WV, Karsten UPenn;Grabber, WI; Moriera, LA;Mohtahr, purdue; Randhir, UMass). Additional details provided in the objectives.doc attachment.
   
4. Develop science-based tools and educational materials to promote environmental stewardship in US dairy and beef industries. Additional details provided in the objectives.doc attachment.
   

Methods

To read the entire Methods section, please refer to the attachment 'Methods.doc.'

Measurement of Progress and Results

Outputs

• Completion of specified experiments in each cooperator state.
• Public release of new models or new versions of current models maintained by project collaborators.
• Publication of results in lay proceedings and scientific publications.
• Presentations at conferences and scientific meetings.
• Linkages with environmental agencies, NRCS, and conservation districts.
• Output 6 Funding to conduct research that meets these objectives.

Outcomes or Projected Impacts

• Increased awareness of whole farm nutrient management by producers, NRCS, conservation districts and environmental agencies.
• More economically and environmentally sustainable systems for dairy and beef production.

Milestones

(2005): Begin objective work in each cooperator state.

(2006): Begin reporting results of experiments and the development and validation of model components.

(2007): Continue with integration of research data and model development. Focus on outreach efforts.

(2008): Continue with integration of research data and model development. Focus on outreach efforts.

(2009): Finalize project objectives and plan for ongoing regional research activities.

Projected Participation

View Appendix E: Participation

Outreach Plan

Please refer to Objective 4: (Outreach) in the attachment Methods.doc, for specific outreach plans and activities. Outreach activities of this project will be targeted to dairy and beef producers, producer organizations, university extension, state and federal agricultural and environmental agencies, NRCS field staff, undergraduate and graduate education, agricultural professionals and elected officials. The models, IFSM and GRASIM, are available and can be downloaded from the web. They will continue to be updated as new knowledge is integrated into the models. In addition, education and extension tools based on excel spreadsheets will be developed that will help producers and ag professionals better understand how nutrition, manure management, livestock housing and management, cropping decisions and herd expansion impact N and P dynamics on dairy and beef farms. Spreadsheets that help producers understand better how forage quality affects profitability and nutrient flows on-farm will also be developed and made available. These tools will be made available through websites, journal publications and conference proceedings. Workshops and seminars will be held in cooperator states that highlight the integrated nature of nutrient management on farms. The WPBNET has been selected as an educational tool to be incorporated into the National Comprehensive Nutrient Management Planning Curriculum project led by Robert Burns of Iowa State and a cooperative project with the Natural Resources Conservation Service. The software and other publications generated in the proposed work will be useful to farmers, educators, policy makers, regulators, commodity groups, politicians, and other researchers. The information will aid farmers as they make strategic plans for crop production and manure management. Extension Specialists will obtain useful information for extension workshops and other forms of teaching or consulting with farmers on issues related to grazing, manure management, and cropping systems. The results will provide a better understanding of the costs, benefits, and potential impact of legislation on the dairy industry.

Organization/Governance

The voting membership of the technical committee consists of a technical representative from each participating USDA unit or state agricultural experiment station (SAES) as designated by the SAES director. Non-voting members include the regional administrative adviser, the CSREES representative, and additional representatives from participating SAES and USDA units. All voting members are eligible to hold an office on the technical committee. These officers are the chair and the secretary. The chair, in consultation with the administrative advisor, notifies the technical committee members of the time and place of meetings, prepares the agenda, and presides at the annual meeting of the technical committee. The chair also prepares the annual report of the regional project. The secretary records and distributes the minutes of the technical committee meeting. A new secretary is elected at the annual meeting of the technical committee and succeeds to chair position at the time the annual report is filed with the administrative advisor.

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Land Grant Participating States/Institutions

CA, IL, LA, MA, MD, MI, NJ, NY, OR, UT, VA, WA, WI, WV

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University of Pennslyvania, USDA-ARS/Pennslyvania, USDA-ARS/Wisconsin