ABSTRACT
The increase in productivity of currently cultivated land and the opening of new areas for agricultural purposes are essential to maintain or improve food and fiber supplies. South America is the continent with largest potential to advance its agricultural frontiers to new areas of savannas and forests. An increase in present needs and aspirations or an increase in the need to maintain the ability of the system for the future break the balance and the sustainability of a given agricultural system. The two ecosystems that predominate in tropical South America are rain forests and savannas. This chapter presents results and advances of research on sustainable agricultural systems for the Amazon rain forest and the Brazilian Cerrados. The population of the Amazon plains is around 15 million people. Though Oxisols and Ultisols are dominant in the Amazon plain, Inceptisols, Entisols, and Alfisols predominate in the high jungle.
