ABSTRACT
Renewed interest in using legumes to provide nitrogen for cash crops is just one of many indications that the stress of nonpoint pollution on regional and global life-support systems is bringing about a major change, almost an about-face, in the philosophy and technology of management—not just for agricultural systems but for all production systems (see Figure 13.1). Contamination of surface and groundwater by agricultural chemicals, soil erosion fromboth urban and rural landscapes, increases in greenhouse gases, and acid rain from power plants currently pose the greatest threats to the earth's life-supporting atmosphere, soil, and water bodies. Such nonpoint pollution sources, unlike point sources, cannot be controlled from the output side of a production system; they can only be controlled from the input side by what I call input management.
