ABSTRACT
Contamination of the water-soil-plant system with pesticides and fertilizers, in addition to breaking up the soil structure due to inadequate use of machinery and implements, is one of the main problems caused by intensive agriculture. The implementation of integrated cropping systems and the reduction of the external energy requirements have been suggested to minimize these problems. The organic cropping system is defined as a production system that is sustainable in time and space, by means of management and protection of the natural resources, without the use of chemicals that are aggressive to humans and to the environment, retaining fertility increases, soil life and biological diversity. Thus, the use of highly soluble fertilizers, pesticides and growth regulators must be excluded in
this system (Paschoal, 1995). Not only does the system have to satisfy the need for reducing the environmental negative-impact problems caused by intensive agriculture, it must also be economically competitive. In comparing the organic and the conventional cropping systems, an important step is to establish which social, economic and ecological factors influence the production systems the most. Besides, a knowledge of those factors allows for a better understanding of how the production systems are structured and how they work.
