The dynamic North Florida dairy farm model: A user-friendly computerized tool for increasing profits while minimizing N leaching under varying climatic conditions

This paper describes the computer implementation of the Dynamic North Florida Dairy farm model (DyNoFlo Dairy). The DyNoFlo Dairy is a decision support system that integrates nutrient budgeting, crop, and optimization models created to assess nitrogen (N) leaching from North Florida dairy farm systems and the economic impacts resulting from reducing it under different climatic conditions. The decision support system, based on Excel^(R) and Visual Basic^(R) software, responds to dairy-specific environmental (climate and soils) and managerial characteristics (livestock management, waste management, crop systems management) and can be used to study the economic and ecologic sustainability of these systems. The DyNoFlo Dairy model is a dynamic adaptation of the framework ''balance'' of nutrients in dairy farms, commonly used in Florida. The DyNoFlo Dairy model incorporates Markov-chain probabilistic simulation of cow-flows and crop simulation for historical climatic years El Nino southern oscillation (ENSO), automated optimization of managerial options, participatory modeling, and user friendliness. This paper discusses the model components and its computer implementation in a user-friendly application. The model was parameterized for conditions found in North Florida dairy farm systems. It is intended to be a tool for producers, regulatory agencies, and extension services, and because of that, participatory and interdisciplinary work was pursued during model creation, calibration, and validation. A case study for a synthesized North Florida dairy farm using the DyNoFlo Dairy model found substantial differences in the N leaching for different ENSO phases and other managerial factors; and the possibility of decreasing N leaching up to 25% while still maintaining profitability levels.

[1]  Peter B. R. Hazell,et al.  Mathematical Programming for Economic Analysis in Agriculture. , 1987 .

[2]  Gerrit Hoogenboom,et al.  Modifying DSSAT Crop Models for Low‐Input Agricultural Systems Using a Soil Organic Matter–Residue Module from CENTURY , 2002 .

[3]  E. C. French,et al.  Nitrogen removal and nitrate leaching for forage systems receiving dairy effluent. , 2002, Journal of environmental quality.

[4]  C. Alan Rotz,et al.  Economic and Environmental Implications of Small Grain Production and Use on Pennsylvania Dairy Farms , 2002 .

[5]  John O.S. Kennedy,et al.  An adaptive decision-making aid for dairy cow replacement , 1993 .

[6]  Anton Bezuglov,et al.  AFOPro: a nutrient management decision support system for the United States , 2004 .

[7]  W. Parton,et al.  Analysis of factors controlling soil organic matter levels in Great Plains grasslands , 1987 .

[8]  W. Rawls,et al.  Estimating generalized soil-water characteristics from texture , 1986 .

[9]  W. Powers,et al.  Components of dairy manure management systems. , 1994, Journal of dairy science.

[10]  G. R. Bryan,et al.  Optimizing model: insemination, replacement, seasonal production, and cash flow. , 1992, Journal of dairy science.

[11]  Cisca Joldersma,et al.  Methodology for participatory policy analysis , 2001, Eur. J. Oper. Res..

[12]  L. Lanyon,et al.  Dairy manure and plant nutrient management issues affecting water quality and the dairy industry. , 1994, Journal of dairy science.

[13]  Luis Orlindo Tedeschi,et al.  Potential environmental benefits of ionophores in ruminant diets. , 2003, Journal of environmental quality.

[14]  R. Huirne,et al.  Coping with Risk in Agriculture , 1997 .

[15]  C. R. W. Spedding,et al.  Systems theory applied to agriculture and the food chain , 1990 .

[16]  L. A. Hunt,et al.  Data for model operation, calibration, and evaluation , 1998 .

[17]  D. M. Jansen,et al.  Ex-ante assessment of costs for reducing nitrate leaching from agriculture-dominated regions , 1999, Environ. Model. Softw..

[18]  Ruud B.M. Huirne,et al.  The Dutch Mineral Accounting System and the European Nitrate Directive: implications for N and P management and farm performance , 2002 .

[19]  Richard K. Koelsch,et al.  DEVELOPMENT OF STANDARD METHODS TO ESTIMATE MANURE PRODUCTION AND NUTRIENT CHARACTERISTICS FROM DAIRY CATTLE , 2003 .

[20]  A. D. Vries,et al.  Economics of Delayed Replacement When Cow Performance is Seasonal , 2004 .

[21]  A. Moser,et al.  Modelling of growth of , 1997 .

[22]  M. J. McGregor,et al.  Farming systems research/extension in the European context. , 1994 .

[23]  G. Hoogenboom,et al.  Understanding Options for Agricultural Production , 1998, Systems Approaches for Sustainable Agricultural Development.

[24]  L O Tedeschi,et al.  Effect of monensin on the performance and nitrogen utilization of lactating dairy cows consuming fresh forage. , 2001, Journal of dairy science.

[25]  A. Kuipers,et al.  Reducing nutrient losses on dairy farms in The Netherlands , 1999 .

[26]  Earl O. Heady,et al.  Linear Programming Methods , 1958 .

[27]  C. Topp,et al.  Modelling Productivity and Nitrate Leaching in a Simulated Dairy Farm , 2003 .

[28]  James W. Jones,et al.  The DSSAT cropping system model , 2003 .

[29]  James W. Jones,et al.  Decision support system for agrotechnology transfer: DSSAT v3 , 1998 .

[30]  J. R. Kiniry,et al.  CERES-Maize: a simulation model of maize growth and development , 1986 .

[31]  J. B. Dent,et al.  Modelling the growth and utilisation of kikuyu grass (Pennisetum clandestinum) under grazing. 1. Model definition and parameterisation. , 2000 .

[32]  Richard Kilmer,et al.  Florida Dairy Farm Situation and Outlook 2008 1 , 2005 .

[33]  G.W.J. Giesen,et al.  Economic and environmental consequences of different governmental policies to reduce N-losses on dairy farms. , 1994 .

[34]  D. Bouldin,et al.  Impact of dairy farming on well water nitrate level and soil content of phosphorus and potassium. , 1999, Journal of dairy science.

[35]  Cynthia Rosenzweig,et al.  ENSO, seasonal rainfall patterns and simulated maize yield variability in Zimbabwe , 1998 .

[36]  R. A. Nordstedt,et al.  Dairy manure management: strategies for recycling nutrients to recover fertilizer value and avoid environmental pollution , 1991 .

[37]  I. R. Johnson,et al.  Plant and Crop Modelling: A Mathematical Approach to Plant and Crop Physiology , 1990 .