MOBILITY EVALUATION OF IONS NITRATE AND AMMONIUM IN AGRICULTURAL AREA WHERE USED CATTLE WASTEWATER AS FERTILIZER SOURCE

Abstract

The aim of this study was to evaluate the mobility of nitrate and ammonium ions in a Ultisol when applied wastewater dairy cattle ( ARB ). The experiment was conducted in the Agroecological Production Integrated System, located in the municipality of Seropédica, State of Rio de Janeiro. In the area used in this work is cultivated the culture of fig (Ficus carica L.), variety Roxo de Valinhos. Different blades of ARB were applied to the soil as a source of nitrogen fertilization (T1-0% of ARB and additional fertilizers with castor pie, T2-50% of the recommended dose of N supplied by the ARB and the other 50% with the castor pie, T3-75% of the recommended dose of N supplied by the ARB and the other 25% provided by the castor pie, T4-100% of recommended dose of N provided by the ARB). In the experimental plots were installed extractors 0.15 and 0.60 m deep. Nitrate concentrations obtained were very high, with values of up to 323 mg.L- 1. However, the values of ammonium in the soil solution were low, with values below 0.44 mg L-1. The results indicate the need for close monitoring in the use of ARB and castor cake in agricultural areas.