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Historical Development and Applications of the EPIC and APEX Models

Author

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  • Gassman, Philip W.
  • Williams, Jimmy R.
  • Benson, Verel W.
  • Izaurralde, R. Cesar
  • Hauck, Larry M.
  • Jones, C. Allan
  • Atwood, Jay D.
  • Kiniry, James R.
  • Flowers, Joan D.

Abstract

The development of the field-scale Erosion Productivity Impact Calculator (EPIC) model was initiated in 1981 to support assessments of soil erosion impacts on soil productivity for soil, climate, and cropping conditions representative of a broad spectrum of U.S. agricultural production regions. The first major application of EPIC was a national analysis performed in support of the 1985 Resources Conservation Act (RCA) assessment. The model has continuously evolved since that time and has been applied for a wide range of field, regional, and national studies both in the U.S. and in other countries. The range of EPIC applications has also expanded greatly over that time, including studies of (1) surface runoff and leaching estimates of nitrogen and phosphorus losses from fertilizer and manure applications, (2) leaching and runoff from simulated pesticide applications, (3) soil erosion losses from wind erosion, (4) climate change impacts on crop yield and erosion, and (5) soil carbon sequestration assessments. The EPIC acronym now stands for Erosion Policy Impact Climate, to reflect the greater diversity of problems to which the model is currently applied. The Agricultural Policy EXtender (APEX) model is essentially a multi-field version of EPIC that was developed in the late 1990s to address environmental problems associated with livestock and other agricultural production systems on a whole-farm or small watershed basis. The APEX model also continues to evolve and to be utilized for a wide variety of environmental assessments. The historical development for both models will be presented, as well as example applications on several different scales.

Suggested Citation

  • Gassman, Philip W. & Williams, Jimmy R. & Benson, Verel W. & Izaurralde, R. Cesar & Hauck, Larry M. & Jones, C. Allan & Atwood, Jay D. & Kiniry, James R. & Flowers, Joan D., 2005. "Historical Development and Applications of the EPIC and APEX Models," Hebrew University of Jerusalem Archive 18372, Hebrew University of Jerusalem.
    • Handle: RePEc:ags:hebarc:18372
    DOI: 10.22004/ag.econ.18372
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    12. Cortignani, Raffaele & Dono, Gabriele & Doro, Luca & Ledda, Luigi & Mazzapicchio, Graziano, 2010. "An evaluation of the economic impact of Climate Change through a three-stages Discrete Stochastic Programming model," 120th Seminar, September 2-4, 2010, Chania, Crete 109317, European Association of Agricultural Economists.
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    17. Spencer, Daniel S. & Barnes, James N. & Coatney, Kalyn T. & Parman, Bryon J. & Coble, Keith H., 2017. "Property Rights And The Economics Of Non-Point Source Water Regulations In Agriculture: A New Biophysical-Economic Methodological Approach," 2017 Annual Meeting, February 4-7, 2017, Mobile, Alabama 252835, Southern Agricultural Economics Association.
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    21. Hou, Lingling & Hoag, Dana & Keske, Catherine M.H. & Lu, Changhe, 2014. "Sustainable value of degraded soils in China's Loess Plateau: An updated approach," Ecological Economics, Elsevier, vol. 97(C), pages 20-27.
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    24. Gaiser, Thomas & Judex, Michael & Hiepe, Claudia & Kuhn, Arnim, 2010. "Regional simulation of maize production in tropical savanna fallow systems as affected by fallow availability," Agricultural Systems, Elsevier, vol. 103(9), pages 656-665, November.

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