Chemical properties of a soil cultivated with two forage crops fertigated with treated domestic sewage

Abstract

In order to evaluate the chemical changes in soil cultivated with forage crops Tifton 85 (Cynodon spp) and Marandu grass (Brachiaria brizantha), fertigated with treated domestic sewage, an experiment was conducted in a split plot, in 2x5 factorial design with five replications. The factors consisted of two forage (grass and Tifton 85 Marandu) crops in plots and five treatments in the subplots, one fertilized with mineral fertilizers with application of 40 kg ha^-1 of nitrogen and four fertigated with treated domestic sewage with doses of 20, 40, 60 and 80 kg ha^-1 nitrogen. There have been three cuttings of forage plant material always at 30 days after the completion of the application of treatments. After each harvest treatments were applied again. At the end of the third cutting soil samples were collected from each experimental unit to determine the levels of the chemical attributes. The results showed that in short periods, the application of treated domestic sewage in relation to mineral fertilization in forage crop production systems with Tifton 85 and Marandu grass only increased potassium, sodium, sodium adsorption ratio and exchangeable sodium percentage.