The purpose of this paper is to provide a broad overview of …

• Abstract
• Introduction
• Federal standards and legislation
• Nitrogen
• Greenhouse gas emissions
• Phosphorus: Relative Availability of Phosphorus...
• Summary and research needs
• References
• Figures
• Tables

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Table 1. Alum effects on ammonia flux and poultry production.

All treatment effects are significant at the 0.05 probability level. Data from Moore et al. (2000).

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Table 2. The effect of crop rotation and manure application history on nitrate leaching and the economically optimum N rate.

Crop rotation Manure application history NO3–N leached Economically optimum N rate     kg N ha–1 Continuous corn no 20 140 Continuous corn yes 41 100 Continuous corn,   alfalfa no 34  53 Continuous corn,   alfalfa yes 56  40

Values represent the average over two years and two N rates. Data from Andraski et al. (2000).

The amount of N leached was calculated from estimated soil drainage based on water balance and the mean monthly soil water NO₃–N concentrations.

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Table 3. The influence of injection on N₂O fluxes (±SD) from land-applied cattle slurry.

Data from Flessa and Beese (2000).

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Table 4. The influence of alum amendments to poultry litter on dissolved reactive and total P concentrations in runoff from surface applications of litter to pasture.

All treatment effects are significant at the 0.05 probability level. Data from Moore et al. (2000).

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Table 5. The effect of diet modification on swine manure composition.

Diet Total P Dissolved reactive P Phytic acid P   g kg–1 Control 25.5a 11.9a 3.9a PHY 21.2b 11.6a 2.0b HAP 20.7b 10.8a 1.6b PHY + HAP 15.2c  7.9b 0.7b

Data from Baxter et al. (2003).

All diets contained approximately the same total P content. PHY, phytase-amended; HAP, high-available-P corn.

Means with the same letter within a column are not significantly different at the 0.05 probability level.

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