Economic and environmental implications of a phosphorus standard: 160-sow representative farm in Montgomery County, Missouri

Agricultural standards in Missouri dictate how operators of animal operations may land apply manure. Missouri has a nitrogen standard that limits the application of manure to 150 pounds of nitrogen-N per acre. To further protect Missouri's water quality, several proposed regulations for other nutrients have been talked about. Phosphorus is often the limiting nutrient for algal growth that causes eutrophication of surface waters. In order to protect Missouri's waters from eutrophication by nonpoint sources, Missouri Department of Natural Resources is considering the implementation of phosphorus-based regulations on the land application of manure. The phosphorus standard would set the maximum amount of phosphorus that would be allowed to be land applied in manure. This study evaluated the proposed standard for its economic and environmental impact on a 160-sow (366 aue) farm in Montgomery County, Missouri.; A farm-level modeling system was developed to provide policy-makers and farmers with information on the impacts that the phosphorus standard would have on this size of operation. The modeling system included environmental simulation model APEX, a financial simulation model FLIPSIM, and a linear programming, mathematical optimization model that optimized the spreading activities restricted by soil moisture limitations on spreading and labor hours.; The LP model showed that the farm with a 6-month pit capacity and 7.5 acres of cropland per sow was able to spread all the manure produced without having to resort to shipping manure off-farm to keep the pit from overflowing. Assuming a 20% debt level, the financial implications of a phosphorus standard were relatively minor, costing approximately {dollar}0.70/acre. Improvements in water quality from implementing a phosphorus standard on the representative farm modeled in this analysis would be negligible. Since the goal of the phosphorus standard is to improve water quality, it would appear that the phosphorus standard would not contribute much more than the current nitrogen standard. There were only marginal improvements in water quality measures simulated for this farm.