Abstract

"The present study had the objective of evaluating the potential of a biofertilizer and bovine manure as agents to improve soil physical properties. The applied biofertilizer came from residues produced by a Batch biodigestor and the manure came from a dairy. A soil amendment was made in plots of 6 x 3 m with four treatments and three replicates. The treatments, in a volumetric ratio, were: control without amendment; soil:biofertilizer mixture on a 3:1 ratio. Soil:biofertilizer mixture on a 1:1 ratio; soil:manure mixture on a 1:1 ratio. In the second year, the plots were divided in two, leaving subplots of 6 x 1.5 m, one of which had a second amendment with the same organic material and the same ratio. The effects of the treatments were evaluated at one month, one year and two years after the first application. The soil parameters evaluated were: bulk density, specific weight, water retention, water infiltration rate and aggregate stability. A cactus pear (Opuntia ficus - indica (L.) Mill.) plantation was established as a test plant. The application of organic material in great volume provoked a decrease on soil bulk density in the short run; consequently, total porosity increased, particularly the coarse pores (reflected in the pF curve). The specific weight and available water were not different between treatments, while the water infiltration rate increased with amendments. There was an increase in the aggregate stability in the short term, but with successive applications the effect disappeared. Finally, the biofertilizer applications promoted cactus growth of shoots and production of DM."