Material From Original Gov't Discussion Paper
[ Intro to excessive manure application as a concern from original discussion papersource#1, "Common Concerns" section p.6 ]Manure is an excellent natural fertilizer. However, over-application can result in excessive levels of nitrogen in soil, leading to problems such as crop lodging and delayed ripening. Too much manure can also aggravate problems in saline soils.
Over-application may also cause excessive build-ups of nitrates. These accumulations can leach downward and contaminate aquifers, or may run off into surface waters.
Manure application is regulated under the Environment Act through the Livestock Manure and Mortalities Management Regulation. The regulation establishes maximum nitrate levels for soils and requires large-scale livestock production operations to register annual manure management plans. (For further detail, see "Manitoba Regulations and Guidelines.")
Although manure application regulations are based on nitrate concentrations and requirements, phosphorus is the nutrient most often implicated in surface water pollution. Phosphorus is not readily transported by water from the application site because it binds tightly to Manitoba soils. However, even minute amounts of phosphorus carried to surface water can have serious environmental consequences.
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Material From "Common Ground" Government Report
Other Material and References