STRUCTURAL POROSITY AS RATIO OF SOIL COMPACTION IN NO-TILLAGE AND MINIMUM TILLAGE SYSTEM

Resumo

Soil tillage systems and traffic of machines modify the soil structural porosity leading to serious changes in the soil compaction, making them still difficult to characterize. Soil conservationist management system creates favorable conditions to the development of the cultures, making possible appropriate conservation of the soil and of the water. Modifications in the soil structure need studies to determine the best management, improving its productivity making its resources naturals economically sustainable. Soil structural porosity was analyzed at no tillage (NT) and minimum tillage (MT) systems, in experimental area in Foz do Iguaçu, Western of Paraná, whose production has been carried out during five years under NT system, at an Alfisol soil. The samples were collected before wheat seeding and after its crop harvest for determination of particles density, soil bulk density, textural density and soil organic carbon content from depths 0.00-0.05, 0.05-0.10, 0.10-0.15 and 0.15-0.20m. No tillage system favored greater structural porosity in the layer depth from 0 to 0.05 m. The structural porosity is altered when this is compared before the seeding and after its crop harvest in the minimum tillage system