Phosphorus Losses through Agricultural Tile Drainage in Nova Scotia, Canada.

This article discusses how field application of manure can significantly elevate phosphorus concentrations in tile drainage to levels with the potential to cause eutrophication. The authors found that mean total phosphorus concentrations exceeded environmental guidelines at most of their monitored fields. The proportion of soluble phosphorus tended to be greater when total phosphorus concentration was high under coarse-textured soils. Dairy manure was most often applied on permanent cover crops, which did not show as much drainage phosphorus concentration variability as crop rotations. Poultry manure was found to contribute to the highest concentrations