Face the planosols (Albaqualf) importance to the agricultural activities in the South Region of the State of Rio Grande do Sul, Brazil, the effect of chiselling on physical parameters of this soil was studied. Experiments were carried out at the Agricultural Machines Experimental Area of EMBRAPA - CPACT, in Capão do Leão, RS, November, 1994. It was analysed the effect of chiselling at three operating speeds (4.76; 3.63 and 2.58 km h-1), in two levels of soil moisture content (119.6 and 71.7 g kg-1), on bulk density, porosity and soil aggregation. No significant effects due to interaction between moisture content and operating speed were observed. Except for bulk density and macroporosity, which were not affected by water content, physical conditions were improved when the soil was prepared with the highest moisture level. Geometric mean diameter and aggregate stability showed the best results at the lowest operating speed, but no effects of chisel speed were observed on other physical parameters.
physical properties; soil moisture; chisel operating speed; planosol