Author
Submitted to: Elsevier
Publication Type: Book / Chapter Publication Acceptance Date: 9/1/2013 Publication Date: 12/13/2013 Citation: Rotz, C.A., Veith, T.L. 2013. Integration of air and water quality issues. In:Kebreab, E. editors. Sustainable Animal Agriculture. Oxfordshire, UK: CABI. p. 137-156. Interpretive Summary: An intepretive summary is not required. Technical Abstract: Managing farms to reduce or control the various nutrient losses affecting air and water quality is complex. There are many interactions among farm components, so reducing one source or type of emission may exacerbate others. For example, reducing ammonia emissions from manure leads to greater concentrations of N in manure during long-term storage and field application, which can cause greater nitrate leaching losses to groundwater and greater nitrous oxide formation and emission to the atmosphere. Simultaneous reduction of all environmental impacts requires comprehensive evaluation and management of all aspects of the farm including profitability for the producer. This type of evaluation is best done through process-level modeling and simulation of farming systems. To demonstrate the effects of management on farm profitability, the environment and the interactions between air and water quality, several farm simulations were done with the Integrated Farm System Model. These simulations consisted of alternatives for animal, manure and crop management in dairy and beef farming systems. The simulations included predictions for the major pathways of nutrient losses, whole farm balances of the major nutrients and the environmental footprints of reactive N loss, energy use and carbon emission. Within each management group, strategic changes were compared to illustrate the resulting environmental effects along with the producer’s costs and profit. Process level simulation provides perhaps the only feasible method for conducting a comprehensive environmental and economic assessment of management options for improving the sustainability of farming systems. For a more comprehensive evaluation of livestock agriculture’s effect on the environment, farm models need to be integrated with watershed and air shed models to track the filtering and transformation of nutrients to their final destination. |