Physicochemical effects of long-term deposition of sewage sludge on Brazilian Oxisol

The aim of this work was to evaluate the effect of doses of sewage sludge (SS) when applied for sixteen consecutive years to the Brazilian Oxisols Typic Haplothox (sandy) and Typic Eutrorthox (clayey), on the chemical characteristics of soil fertility. The experiment was carried out in a field at Jaboticabal, SP, Brazil, using experimental design in randomized blocks with 4 treatments and 5 replications. Sewage sludge was applied on soil surface and incorporated at the 0–10 cm depth with a light harrow. Sixty days after SS application, soil samples were collected at the depth 0–20 cm (10 simple samples per plot, which were mixed to obtain a composite sample). The treatments were T1 = no SS and mineral fertilization based on soil chemical analysis, T2 = 5