Heavy metal and fertility in a Tropical Oxisol amended with sewage sludge under Eucalyptus plantation

Abstract

The objectives of our study were to evaluate i) the soil fertility and fractionation of Ba, Cd, Cu, and Zn in the topsoil layer (0-0.20 m depth); and ii) production and concentration and accumulation of Ba, Cd, Cu, and Zn in the components of Eucalyptus trees at 36 months after sewage sludge (SS) application, with or without mineral P fertilizer, compared to mineral fertilization. Application of SS (at N criteria) with P increased soil organic matter and heavy metal concentrations, which were mostly bound to the oxidic and organic matter fractions. SS provided Eucalyptus production and heavy metal concentrations and accumulation in the trunk, branches, and leaves similar to mineral fertilization for high wood production. The application of SS (at N criteria) supplied with P increased soil heavy metal, fertility, and Eucalyptus production, without risk of environmental contamination.