Pedogeomorphological interactions in the Preto River Basin, Southern Espinhaço Range, Southeastern Brazil

Abstract

This paper presents a study of the relationships between relief and soils in the Preto River basin, north central region of the State of Minas Gerais, Southeastern Brazil. This basin is inserted in the Southern Espinhaço Range, which is a geomorphological feature that resulted from compressive tectonic stresses on quartzitic rocks during the Mesoproterozoic. A morphological map was prepared from aerial photographs at 1:40,000 and 1:60,000 scales and was used as a basis for the elaboration of the exploratory soil chart, which was subsequently checked by means of descriptions of soil profiles in the field. The soils of the Preto River basin were classified into three soil systems: Lateritic, Podzolic and Lithodependent, with a very particular distribution. In the upper river course podzolic and lithodependent soil systems predominate. In the middle and lower river courses the lateritic soil system dominates, while lithodependent soils develop on steeper slopes. The relief is affected by major structural and tectonic controls, especially in the upper river course, whereas in the middle and lower river courses erosion and geological structures predominantly model the landscape.