The packing condition of the soil is important for providing direction for land management. In soils developed from recent sediments, the tendency to packing may be related to inherited characteristcs from sedimentation conditions. In a soil toposequence from sandy sediments of Barreiras geological group, in Caravelas city - Bahia, eight soil profiles were selected, five of them from a eucalypt plantation. The soils were allocated in five great groups: Fluvaquent (P1),Duraquod (P2, P8), Haplorthod (P3), Hapludult (P4, P5, P7) and Plintaquult (P6) according to the 7th approximation of USA soil taxonomy. Soil bulk density was determined in 41 horizons along with minimum and maximum soil bulk densities. Values of soil bulk densities were located between the two other densities, thereby obtaining the relative densities. The sand was subdivided into 21 size classes by standard sieves and the data were used to determine mean size, inclusive graphic standard deviation, inclusive graphic skewness and graphic kurtosis. It was observed that higher fine sand content combined with unsorted sand grains enhanced closer packing of soil particles, inducing increments of relative density in soil horizons more resistant to penetration.
bulk density; particle size distribution; sand size; sedimentology; relative density