Trace elements in two Oxisols after annual application of sewage sludge for thirteen years

• Main Authors: Maurício Gomes de Andrade, André Suêldo Tavares de Lima, Wanderley José de Melo, Eder José dos Santos, Amanda Beatriz Herrmann
• Format: Article
• Language: English
• Published: Universidade Estadual de Londrina 2014-02-01
• Series: Semina: Ciências Agrárias
• Subjects: Tropical soils; Heavy metals; Soil contamination; Fertilizers; Soil pollution; Urban residues
• Online Access: http://www.uel.br/revistas/uel/index.php/semagrarias/editor/submission/12852

This experiment aim was to evaluate the contamination of the trace elements (TE) arsenic, barium, cadmium, chromium, copper, mercury, molybdenum, nickel, lead, selenium, and zinc considered in the CONAMA resolution 375 after 13 years long using sewage sludge (SS) as fertilizer in two soils: an Eutroferric Clayed Red Latosol (Rhodic Eutrudox – RE) and a Dystrophic Red Latosol (Typic Haplorthox – TH). Experiment in the field under maize cultivation had four treatments (0, 5, 10, and 20 t of SS ha-1, dry weight), five replications and an experimental design in randomized blocks. The agrochemicals (dolomitic limestone, single superphosphate, and potassium chloride), SS, soils, and the certified reference materials were digested according to the USEPA 3051A method and the chemical elements were quantified by ICP OES. The TE contents found in the agrochemicals used should not cause immediate environmental impact. The higher TE values were found in the RE and they did not reach the agricultural (more stringent) Investigation Level (IL) yet, according to 420 CONAMA resolution. Persisting the actual SS fertilization amount applied in the soil and the TE concentration in the SS is foreseen that Ba, Cd, Cr, Cu, Ni, and Zn will be the first elements to reach the IL in the RE.