Disponibilidade de nutrientes e metais pesados em milho cultivado com lodo de lavanderias industriais em latossolo vermelho distrófico

Abstract

The Northwest Region of Paraná State contains the largest textile pole of Southern Brazil. The laundry industries produces sludge which contains high COD, color, and some microelements that do not permit direct disposal to the soil or rivers, although it can become a source of plant nutrients and can be used as soil organic matter amendment. The present work evaluates in a competition essay of 3 industrial laundries sludge, their effect on the dry matter production and heavy metal content using corn as test plant. The corn crop was conducted for 120 days. The sludges were characterized in their chemical attributes, heavy metal content and by X-ray diffraction (XRD). The dry matter productions of the corn allowed classifying the sludges in three categories. All sludge samples analyzed had low content of extractable heavy metals, whose average concentration was, for Fe, Cr, Co and Ca, 1,48; 0,61; 0,76 and 1,70 mg kg-1, respectively. The average available content of microelements Ni, Fe, Co, Zn and Mn was 3,68; 279,64; 4,48; 70,83 and 761,49 mg kg-1, respectively. Titanium, common in dyes, did not present available content, although total content was determined up to 24364,14 mg kg-1. The plant tissue data analysis, shoot and grain, did not present Cr, Ti, Ni, Co and Cd concentrations The Xrays diffraction data for raw samples showed, mostly, the presence of an amorphous phase and quartz reflexes.