Parâmetros Físicos e Químicos de Referência em Solos de Unidades de Conservação Florestal da Bacia do Paraná 3, Brasil (Physical and Chemical Parameters of Reference Soils in Forest Conservation Units of the Paraná Basin 3, Brazil)

Abstract

The characterization of standard pedological parameters in forest soils, free of anthropogenic contamination, is important, since it allows the variables analyzed to serve as the natural base level of a given region. In a country as large as Brazil, with different climates, reliefs and vegetation, each state should independently seek its own reference values in relation to the characteristics of the soils. In order to obtain basic information about soil physical and chemical properties in the Paraná Basin 3 (BP3), 73 soil samples were collected in Conservation Units and Forest Remnants. The samples were air dried, texture and chemical attributes, pH in water; organic carbon (OC), K + , Na + , Ca 2+ , Mg 2+ , Al 3+ , H+Al, and P were determined (EMBRAPA, 1997). From the results obtained, the cation exchange capacity (CEC) at pH 7 and base saturation percentage (V%) were calculated. The data obtained were statistically evaluated through Principal Component Analysis, which showed the separation of the samples into three distinct groups according to their similarities. Among the characteristics studied, it was possible to verify the predominance of the Latosol, Nitosol and Neosol classes, which together added up to 92% of the total samples. The pH of the samples ranged from extremely acidic to almost neutral. Most of the samples showed a negative association between clay content and CEC. BP3 soils had a mean OC content of 23.60 g / kg and a positive association with CEC.