ABSTRACT
This study aimed at evaluating the effects of pig slurry application with mineral fertilizer on ions leaching from the soil in soybean crop. The experiment was carried out in 24 drainage lysimeters under protection. The soybean cultivar CD 202/COODETEC was sown in a soil that received 0, 100, 200 and 300 m³ha-1of pig slurry in one cycle, with or without mineral fertilizer. There were three samplings of soil throughout the trial to determine the pH, N, NO3-, K+, Ca2+, Mg2+, Na+, Cu+2, Zn+2, OM, CEC, EC and SAR six times during the crop cycle. The yield was determined in the plants. In soil, pig slurry increased the concentrations of pH, NO3-, K+, Zn+2, OM and CEC, while mineral fertilizer increased P and Zn+2concentrations. The limits observed for the leachate parameters did not present environmental problems according to the Brazilian legislation, but in the intermediate and long term, there special attention should be given to NO3-, P, Na+, EC and SAR. Soybean yield was higher with mineral fertilizer and increased with pig slurry application.
ABSTRACT
The objective of this work was to evaluate the environmental effects of the use of pig slurry to irrigate the corn crop grown in a typical Red Distroferric Latosol and in leachate composition. Twenty four lysimeters, filled with soil, in a protected environment, received five doses of pig slurry (0; 112.5; 225; 337.5 and 450 m³ ha-1 per growing cycle) combined with two mineral fertilization doses (50 and 75% of the recommended dose - 80 kg ha-1of nitrogen). Corn height and yield were evaluated, as well as nutrients in the soil and in leachate. From the results obtained in the first year of experiment, it was concluded that the concentrations of nitrate increased by increase of pig slurry application, and thus, it would be necessary to develop further studies in medium and long term.