Chemical and mineralogical soil atributes from Comperj area due to variations in lithotype, landscape position and vegetation cover

Abstract

Establishing Comperj (petrochemical complex Petrobras and partner companies at Itaboraí city, Rio de Janeiro State, Brazil) involves a great impact on natural environment, while it is an opportunity for actions of environmental compensation. The objectives of this study were to characterize soil chemistry and mineralogy of Comperj
area, based on landscape, particle size distribution and soil morphology, also considering different parent materials, landscape positions (shoulder, backslope and footslope at the hillslope and toeslope at floodplain) and vegetation cover groups. Different landscape positions, comparing toeslope and average hillslope, have differential behavior on several chemical attributes, besides those associated with landscape position itself (topography and water regime). Along the hillslope, differences on surface soil samples also occurred, considering studied attributes, among different parent materials and vegetation cover
groups. Sites of both vegetation cover groups (forest and pasture) along the hillslope showed differences on many chemical attributes, except for organic C average values
that were not differentiated among them. Soil mineralogy on all samples was extremely kaolinitic and there were small differences among parent material groups. Soil
consistencies observed were very to extremely hard on both soil parent material groups, Proterozoic and Tertiary.