Phase 5 Model NPS Inputs. Methods and Calculations. Overview of Inputs. Attempt is to outline clearly defined input requirements that are easy to update. Nutrient Assimilative Capacity crop uptake, legumes, waste disposal Nutrient Sources
Methods and Calculations
Suitable Crop Rotations / Climate
Modeled as Double-Crop
Chemical fertilizer applications on hay said to vary throughout the basin. Therefore, hay crop nitrogen is calculated with the following information:
α – No breakdown of percentages between species, turkey normally has higher P excretions/unit waste.
β - Pennsylvania submitted results of assessment given by a feed industry representative, est. 90% adoption.
γ - Post-phytase data for West Virginia data was for the period 2001 to 2004, assume phytase adoption overlap.
Reductions when control group in phytase study where animal received ONLY phytase, no other dietary modifications generally do not exceed 23-24%:
Percent of Crop Need N
Nutrient Managed Composite
Non-Nutrient Managed Composite