SISTEMAS E SUCESSÕES DE CULTIVOS NA FERTILIDADE DE UM SOLO DA REGIÃO DA AMAZÔNIA.

Soil management, featuring techniques that make possible great sustainability, aims at soil recuperation and sustainability, greater productivity and greater economic gain to the producer. Soil fertility (phosphorus, potassium, organic matter, pH) is evaluated with regard to depth of samples and soil and crop preparation systems. Experiment was undertaken in Red-Yellow Latisol and a sub-subdivided split scheme was adopted. Soil preparations comprised (1) PRT - traditional preparation (plowing grid and two level grids); (2) PRA - alternative preparation (subsoil); (3) PDA - zero tillage with alternative preparation every four years; (4) PDC - continuous zero tillage. Crop sequence was the second factor employed, namely: (1) SF: soybean - beans; (2) MF: corn - bean; (3) SM: soybean - corn; 4) MM: corn - corn. PRT and PDC presented lower fertility rate at the soil surface layer. PRT presented less amounts of phosphorus, potassium and organic matter; pH had lower rates in PDC and PRT. [ABSTRACT FROM AUTHOR]