Location: Botucatu, São Paulo State/Brazil.Experimental design : completely randomized block, with subdivided plots and eight replications.Plots: I SEASON-FALLOW: soybean/fallow/maize/fallow; II SEASON-OFF SEASON: soybean/white oat /maize/common bean; III SEASON-GREEN MANURE: soybean/millet/maize/cowpea; IV SEASON-LIVESTOCK: soybean/B. ruziziensis/maize/B. ruziziensis.

Subplots: superficial liming and Ca-Mg silicate application, to raise base saturation up to 70%, and a control without any correction source.

Determinations: Aggregate stability, soil density, macro, micro and total porosity, soil penetration resistance and moisture.

Data analyses: Means were compared by the t test (LSD) at a probability level of 5%.

This research was conducted aiming to evaluate the effects of crop systems and materials for acidity correction on soil physical attributes.

MATERIAL AND METHOD

RESULTS

CONCLUSION

INTRODUCTION

Superficial application of materials for acidity correction increases soil total porosity, accentuated down to 0.20 m and 0.10 m after silicate and lime application, respectively. B. ruziziensis cultivated between summer crops increases aggregate stability-index down to 0.10 m the soil profile. Soil structuring is harmed by the cultivation of only a crop per season, decreasing aggregate stability and increasing penetration resistance in superficial soil layers.

GUSTAVO SPADOTTI AMARAL CASTRO & CARLOS ALEXANDRE COSTA CRUSCIOL Department of Plant Production/Agriculture

FCA/UNESP-BOTUCTU, SP. gsacastro@hotmail.com

Soil physical attributes affected by crop systems and materials for acidity correction

OBJECTIVE

Support:

Organic soil

Tillage soil

water infiltration

water retention

Carbon accumulation

Nutrient

Cycling