Artigo Acesso aberto Produção Nacional Revisado por pares

Heavy metals in Oxisols amended with biosolids and cropped with maize in a long-term experiment

2005; UNIVERSIDADE DE SÃO PAULO; Volume: 62; Issue: 4 Linguagem: Inglês

10.1590/s0103-90162005000400012

ISSN

1678-992X

Autores

Katarzyna Wójcik-Oliveira, Wanderley José de Melo, Gener Tadeu Pereira, Valéria Peruca de Melo, Gabriel Maurício Peruca de Melo,

Tópico(s)

Soil Management and Crop Yield

Resumo

Biosolids comprise organic matter and plant nutrients, but are also a source of heavy metals hazardous to soils, plants and humans. The aim of this work was to evaluate accumulation, movement in the soil profile and availability to maize plants of heavy metals in two oxisols amended with biosolids for five years. The experiment was carried out in Jaboticabal, SP, Brazil, under field conditions, using a split-plot design. Biosolids were added to the soils at four different rates, 0.0 (control with mineral fertilization), 2.5; 5.0 and 10.0 t ha-1, dry weight basis, annualy for three years. In the fourth and fifth years, the 2.5 t ha-1 treatment rate was increased to 20.0 t ha-1. In the fifth year, soil samples were collected at 0-20 and 20-40 cm depths and analyzed for Cu, Ni, Mn, Pb and Zn total and extractable (Mehlich 1) contents. Biosolids increased the concentration of Ni and Zn in the Typic Eutrorthox, and of Ni, Pb, Zn and Cu in the Typic Haplorthox, but values did not exceed critical limits established by legislation. The elements generally accumulated in the 0-20 cm depth. Lead and Ni concentrations in grains were below detection limits. In general, heavy metals contents in maize plants were not affected by application of biosolids. Mehlich 1 extractant was not efficient in predicting the availability of Ni, Mn, and Pb to maize plants.

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