Efeito do uso de fertilizantes e da irrigação nos teores de nitrato em diferentes profundidades.

Abstract

The recognition that the quality of groundwaters is almost as important as its amount brings to the actual moment the need of proper attention and protection to the existing reservoirs, because the usage of this possession becomes bigger and bigger and without exploratory control, The groundwater is a renewable natural source and its contamination can transform it into a non-usable source, The research was carried out in the Center of Environmental studies from a State University in São Paulo - Brazil, with the objective of characterizing the contamination of seepage water in a lettuce crop superficially irrigated with water containing urban sewage and treated water, The lettuce was fertilized with mineral fertilizer and organically with cattle and chicken manure and with biofertilizer (cattle manure anaerobically fermented), The experimental parcels were made of amianthus boxes containing 500 liters of soil and superficial area of 1 m2, with casual distribution in green house protected with polietilen, The results demonstrated that occurs contamination of the percolated water by the raising of the analyzed ions concentration (nitrate) in soil solution, coming from the mineralization of organic matter or from the nitrogen fertilizer solution used (ammonium nitrate) as a corrective in the initial manuring and covering manuring.