Phytoremediation of soils contaminated with metals: Current outlook and prospects of use of forest species

Abstract

Phytoremediation is a technique that uses plants to recover contaminated soils. This method has advantages because of its permanent nature, combined with low maintenance costs, protection against wind and water erosion and greater soil structure. Currently, most of the researches related to species capable of phytoremediation of soil contaminated with metals work with annual cycle plant species. However, due to limitations found in these species, the possibility of using forest species in phytoremediation programs is increasingly projected. Be suitable for revegetation of contaminated areas and also provide economic return. The purpose of this review was to present the main techniques of phytoremediation used and to analyze the perspectives of the use of forest species in phytoremediation programs. The reports in the literature point out several of these species with real capacity of use, in addition they have been pointed as tolerant to soils in stages of great contamination, and their capacity of fixation of contaminant in their structures for a longer time in relation to vegetal species of annual cycle. The limiting factor in the full use of these species is still the small number of researches, which consequently causes many effective species to no longer be identified for phytoremediation.