Feeds imported to support rapidly expanding intensive livestock operations (ILOs) in North Carolina represent significant quantities and proportions of "new" nutrients in local watersheds. The Cape Fear and Neuse River basins include largefractions of total state inventories of hogs, turkeys, chickens, and cattle. Production of hogs, turkeys, and broiler chickens increased substantially in North Carolina during 1985-1995. Due to growth in the demand for feed and declines in feed cropproduction in North Carolina, ILOs must import large fractions of feed grains and soybeans they require from out of state. The corresponding quantities of new nitrogen and phosphorus, including inorganic phosphorus used as a diet supplement, imported inanimal feeds are more than an order of magnitude greater than current annual loads of these nutrients in each river. The eutrophication threat to these river basins and other areas with expanding animal populations from the potential large nutrientloadings, especially phosphorus, associated with ILOs is substantial.
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