The swine industry has grown rapidly in North Carolina in the past decade, with the majority of the growth occurring in a few counties in the Coastal Plain region of the state. With this expansion has come the problem of swine waste disposal. Mr. Blevins, a local farmer in this region, has been raising swine since 1985. The swine waste on his farm is collected in an anaerobic lagoon and then irrigated onto a bermudagrass (Cynodon dactylon(L.) Pers.) pasture where cattle are fed using intensive rotational grazing techniques. A study of Mr. Blevins' farm revealed very high nitrate concentrations in the groundwater(> 110 mg N03-N L-1) and high nitrate levels(> 15 mg N03 kg) in the bermuda grass forage. The soil concentrations of other nutrients such as P, K, Zn, and Cu were also increasing. A case study of Mr. Blevins' operation was developed to encourage classroom discussion and small group analysis of waste disposal issues. The case was the central focus for subsequent lectures in class involving the N cycle. The students were shown a video recording of Mr. Blevins discussing his operation and his concerns for the future. A video of an interview with the administrator for the state regulatory agency was also shown to provide a public policy perspective. The students were asked to make a nutrient management recommendation for Mr. Blevins. A follow-up session was held to discuss the recommendations and review the use of a decision tree for systematically organizing the available information.
- case study,
- swine waste,
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