The soil physical quality is fundamental for the sustainability of citrus production. The objective of this study was to evaluate the homogeneity of soil physical quality in-between the rows of an orange orchard with groundcover management systems. The study was performed in an experimental field with groundcover systems in-between the rows of 'Pêra orange' on 'Rangpur' lime rootstock on a Typic Paleudult, in 1993, in Alto Paraná, in the northwestern region of the state of Paraná, Brazil. An experimental design of random blocks was used, with tree replications. The following groundcover treatments between the rows were studied: bahiagrass (Paspalum notatum), perennial peanut (Arachis pintoi), and the usual management in which weeds of spontaneous vegetation are herbicide-controlled. In May 2003, 216 undisturbed soil samples were collected from the mid 0-15 cm layer in two sampling positions: under and in-between tractor wheel tracks. Soil samples were used to measure: water content at different matric potentials, soil bulk density, total porosity, and soil penetration resistance. Pore size distribution, air capacity, and S index were also calculated. The inclusion of the soil air capacity and S index associated to pore size distribution broadened the understanding of the soil physical alterations caused by perennial groundcover management types in-between rows of orange orchard. The greater drained pore volume under the leguminous perennial peanut reduces water availability to plants, corroborated by higher air capacity and S index. The physical soil quality in-between rows of orange orchard covered with bahiagrass is more homogeneous that the usual management or perennial peanut.
pore size distribution; soil bulk density; soil compaction; soil management; soil quality
