Chemical properties changes of a typical clayey oxisol submitted to different treatments of organic residues

Abstract

The use of organic fertilizers in Brazilian agriculture has been increased recently. With the objective of evaluating the alterations in chemical properties of a typical clayey, oxisol, in Londrina, Londrina PR, Brazil, an experiment was conducted with the application of different organic residues. The following treatments were tested: bovine manure (8 T ha-1), hen manure (3 T ha-1), broiler litter (6 T ha-1), sheep manure (6 T ha-1) and silage residue (8 T ha-1). The experimental design was in randomized blocks with 6 treatments and 3 replications. Each residue was applied twice, in the beginning and 12 months after the experiment installation. Soil samplings were taken at 3, 6, 9, 12, 18, and 24 months after the application of the residues. Each sample was evaluated chemically for the following variables: pH in CaCl2, H + Al, Ca, Mg, K, P, organic matter, CEC and saturation for bases (V). In general way, the organic residues application resulted in alterations in the chemical properties of the soil. The best treatment tested was the sheep manure that promoted a larger increase of exchangeable calcium, organic matter and CEC of the studied soil. The hen manure increased the levels of soil phosphorus.