Amazon Soils. A Reconnaissance of the Soils of the Brazilian Amazon Region

Abstract

The study deals with soils of the Brazilian part of the Amazon basin. Most soils are Latosols, some with soft or hardened plinthite. The Latosols are characterized by a latosolic B horizon as defined in Brazil. Plinthite, its formation and morphology were extensively described. Five main types of hard plinthite were distinguished. The rather uniform soils of the Amazon Planalto proved to be mainly Kaolinitic Yellow Latosols. Various intergrades toward Groundwater Laterites and Red Yellow Podzolic soils were shown to exist. Special attention was given to the relation between the soil conditions and vegetative cover. The mean gross timber volume and the presence of specific tree species were discussed. The suitability was assessed of the soils for agricultural production, especially vegetables, cash crops and some perennials such as oil palms.