Changes in animal production have occurred in response to the need for greater production efficiency and to the changes in per capita consumption. These changes include confinement feeding of livestock and increased animals per production unit. The accumulated wastes at these confined feeding operations have become point sources of potential pollution more amenable to both environmental complaints and regulation, and to better waste management and control. Solutions for satisfactory animal waste treatment and disposal will not be direct extensions of approaches that have been successful for industries and municipalities. Although no one treatment or disposal system will be the solution for all operations, there are a number of approaches that can minimize flagrant pollution problems. The most satisfactory solutions for animal wastes include some type of initial treatment followed by disposal on the land. Possible initial treatment methods include aerated liquid systems, natural drying systems, runoff control measures, and waste holding units. For over-all animal waste management, all aspects of the production scheme should be evaluated for interactions and tradeoffs so that an acceptable environment for the public and an adequate profit for the producers can be obtained. Interdisciplinary approaches are required for successful methods of animal waste management. The paper discusses feasible technical approaches and suggests interdisciplinary approaches that may be desirable.

Plant parasitic nematodes occur naturally in undisturbed soils. Establishment of an agroecosystem promotes the rapid increase of endemic pathogenic species and allows introduction of nonendemic species that quickly establish dominance. Nematodes now cause about 10% loss of yields of crops in the United States. About 20 highly effective nematicides are available to control nematodes and associated plant diseases in a number of crops. Nematode populations can be regulated by a number of soil management practices, including clean transplant, seed production, and crop rotations. Biological control can be achieved by addition of various types of organic matter to soil, some of which are not presently utilized, especially biodegradable solid waste. Over 152 nematode-resistant crop varieties representing 17 major crops are available with resistance from one to three species of the 10 most destructive nematode types. Physical methods of control, including quarantine, sanitation, and crop destruction, are not vigorously applied. All methods available for nematode control have not been utilized in integrated control systems. Further research and development will allow use of integrated management systems, using several basically different approaches to nematode control, with nematicides used to supplement other control methods.