Manure Use for Fertilizer and for Energy. Report to Congress

摘要

The Food, Conservation, and Energy Act of 2008 directed the U.S. Department of Agriculture to evaluate the role of animal manure as a source of fertilizer, and its other uses. About 5 percent of all U.S. cropland is currently fertilized with livestock manure, and corn accounts for over half of the acreage to which manure is applied. Expanded environmental regulation through nutrient management plans will likely lead to wider use of manure on cropland, at higher production costs, but with only modest impacts on production costs, commodity demand, or farm structure. There is widespread interest in using manure as a feedstock for energy production. While current use is quite limited, expanded government support, either direct or indirectly, could lead to a substantial increase in manure use as a feedstock. However, current energy processes are unlikely to compete with fertilizer uses of manure, because they leave fertilizer nutrients as residues, in more marketable form, and because manure-to-energy projects will be most profi table in regions where raw manure is in excess supply, with the least value as fertilizer