Evaluation of the Phytoavailability of Cu(II) and Cr(III) for the Growing of Corn (Zea mays L.), Cultivated in Four Soils of a Toposequence Derived from Basalt

摘要

The environmental contamination, from the pollutants generated by industrial development, has been considered, in the last years, one of the most critical environmental problems and worthy of study, mainly regarding the environmental degradation they cause. The use of areas contaminated by heavy metals for agriculture needs information about the behavior of plants and the dynamics of the metal in the soil, to predict the phytodisposability of these metals, present in these areas and their behavior. The present study consists in verifying whether the chemical and mineralogical characteristics of the soils developed in a basalt-derived toposequence can influence the dynamics of Cu~(2+) and Cr~(3+) ions in the phytodisposability of these metals for commercial crops, such as corn. Increasing the dose of the mentioned copper and chromium salts in the NVef and MTF soils, indicates an increase of Cu~(2+) ion in plants. For the Cr~(3+) ion, it accumulated a large amount in the roots, with no translocation occurring to the aerial part. This indicates the potential of Cr~(3+) ion fixation to the organic and inorganic colloids of the soils and its low mobility in the plant. The concentration and accumulation of metals in plants depend on a number of factors, such as soil class, availability of metal in the soil solution, which is related to the weathering process or to anthropogenic contamination, and plant species.