Estudo da presença de nitrato em folhas de alface irrigada com água residuária e com diferentes tipos de adubação.

Abstract

The environmental impacts originated by incorrect disposal of urban organic residuals in the environment have problems with its control and, as a consequence, big expenses are used to give a solution to the damages made by them, The wrong usage of natural sources like water and soils of areas now known as disturbed by the launching of liquid effluents and solid organic residuals reflects the indifference and lack of capacity of recognizing the environmental problems we have, and the inversion given to the multiple resources which are these two basic possessions to man, soil and water, 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 leaves 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.