No abstract

Granate de Sá e Melo Marques(1) Recebido para publicação em abril de 2005 e aprovado em março de 2007.

RESUMO

This study evaluated Cd and Pb accumulation by castor bean (Ricinus communis cv. Guarany) plants grown in nutrient solution, aiming to assess the plant's ability and tolerance to grow in Cd- and Pb-contaminated solutions for phytoremediation purposes. The plants were grown in individual pots containing Hoagland and Arnon's nutrient solution with increasing concentrations of Cd and Pb. The production of root and shoot dry matter and their contents of Cd, Pb, Ca, Mg, Cu, Fe, Mn, and Zn were evaluated in order to calculate the translocation and bioaccumulation factors, as well as toxicity of Cd and Pb. Cadmium caused severe symptoms of phytotoxicity in the plant's root and shoot, but no adverse effect was observed for Pb. Castor bean is an appropriate plant to be used as indicator plant for Cd and tolerante for Pb in contaminated solution and it can be potentially used for phytoremediation of contaminated areas.

Resumo -O objetivo deste trabalho foi quantificar a retenção e a dessorção competitivas dos ânions nitrato, sulfato, silicato e fosfato na fração argila gibbsítica de um Gleissolo Melânico. Amostras da fração argila foram agitadas em tubos de centrífuga com solução de NaCl 30 mmol c L -1 contendo estes ânions em quantidades equivalentes a 30% das respectivas capacidades máximas de retenção exibidas pela argila. Para fins comparativos, as amostras foram agitadas com a mesma solução contendo 1 mmol c L