ABSTRACT
The growth and development of modem commercial swine and poultry production, essential components of our food supply, are being restricted in some countries and will be restricted in other countries if solutions to the problem of manure disposal are not developed and implemented. Because of the high nutrient content of manure, and thus fertilizing value, land application has been the major means of disposal. However, the amount of manure that can be applied to the land is limited because of buildup of nutrients in and on the soil. The potential environmental impact of nutrient contamination of surface runoff and groundwater is perceived as a major issue facing livestock producers (Coffey, 1992; Van Horn, 1992). The impact of very large amounts of manure being produced in a relatively small land area has led to the development of strict legislation to control pollution caused by animal manure in a few countries. The Dutch case was presented by de Haan (1990) and will be described in Chapter 20 by Jongbloed and Henkens (1996). Also, in a recent review of livestock pollution and politics, Hacker and Du (1993) reviewed legislation and guidelines that have been developed in some countries and regions of the world. The pig and poultry industries have generally received the most attention.
