PHYSICAL-HYDRIC ASSESSMENT OF RED OXISOL CLAY TEXTURE: SUBSIDIES FOR WATER RESOURCES MANAGEMENT IN THE PIRAPÓ-PR-BASIL

Abstract

The assessment of physical and hydric attributes of the soils is important to indicate the active processes in a river basin. In this context, the objective of this study is to assess the physical-hydric behavior of the red Oxisol clay texture for different uses in Pirapó river basin. We collected samples of the red Oxisol clay texture soil surface (Ap) and subsurface (until 20 cm deep) for grazing, temporary crops and native forest according to the criteria in the manual to soil description and collection in the field (LEMOS and SANTOS, 1996). For each type of soil and use, was determined soil density, particles density and total porosity according to criteria in the manual to methods of soil analysis (EMBRAPA, 1997). Permeability was established using Guelph permeameter with the method of one hydraulic load and the resistance to penetration with impact penetrometer.  We found the worst conditions were found in the red Oxisol under temporary crops requiring measures to improve the physical and hydric attributes of the soil.