TY - JOUR T1 - Managing manure for sustainable livestock production in the Chesapeake Bay Watershed JF - Journal of Soil and Water Conservation SP - 54A LP - 61A DO - 10.2489/jswc.67.2.54A VL - 67 IS - 2 AU - Peter Kleinman AU - Kristen Saacke Blunk AU - Ray Bryant AU - Lou Saporito AU - Doug Beegle AU - Karl Czymmek AU - Quirine Ketterings AU - Tom Sims AU - Jim Shortle AU - Josh McGrath AU - Frank Coale AU - Mark Dubin AU - Daniel Dostie AU - Rory Maguire AU - Robb Meinen AU - Arthur Allen AU - Kelly O'Neill AU - Lamonte Garber AU - Mark Davis AU - Bobby Clark AU - Kevin Sellner AU - Matt Smith Y1 - 2012/03/01 UR - http://www.jswconline.org/content/67/2/54A.abstract N2 - Manure presents one of the greatest challenges to livestock (dairy and beef cattle, swine, poultry, equine, sheep, llamas, etc.) operations in the Chesapeake Bay Watershed, serving both as resource and liability. The Chesapeake Bay is threatened by excessive nutrient loadings, and, according to the US Environmental Protection Agency (USEPA), manure is the source of 18% of the nitrogen and 27% of the phosphorus entering the Chesapeake Bay annually (figure 1) (Chesapeake Bay Program 2010). Developing economical, practical, and effective manure management options for livestock producers will not only contribute to the restoration of the Chesapeake Bay, but will also provide a model for other areas where water quality and livestock production objectives must be balanced. The 166,000 km2 (64,000 mi2) Chesapeake Bay Watershed is home to 3.2 million animal units (animal unit = 454 kg [1,000 lbs] of livestock) generating roughly 36 million t (40 million tn) of livestock manure per year. In comparison, the 14 million humans who call the Chesapeake Bay Watershed home generate 3.6 million t (4 million tn) of waste annually (Brosch 2010; Blankenship 2005). The livestock manure contains approximately 259,000 t (285,000 tn) of nitrogen and 70,000 t (77,000 tn) of phosphorus. Most manure is… ER -