Phytoextraction of Trace Metals: Principles and Applications

摘要: Trace elements (TEs) occur at minor concentration (>1 g kg−1) in the organisms, and some are essential nutrients (Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, B, Cl) for animals plants. As a consequence of human activities such as industrial production, mining, transport, agriculture, they released environment high concentrations. TEs can accumulate over time under specific environmental conditions, thus becoming contaminants (Cs, Cr, W, U, Cd, Hg, Tl, Pb, Sn, As, Sb, Se). The risk is associated with mobility bioavailability metals more than their total concentration. When become environmentally mobile move between media (i.e. soil to water), enter food chain by being taken up plants animals. cannot be degraded or broken down toxic organisms tend bioaccumulate environment. For example, selenium (Se) naturally occurring element wide distribution almost all parent materials on Earth. At low concentration, Se an nutrient but toxic. In western side San Joaquin Valley California, soils contain significant quantities soluble mineral salts trace boron (B) that have been leached into shallow groundwater and/or drainage waters because irrigation practices Kesterson Reservoir California. Soluble bioaccumulated avian resulted disaster mortality reproduction failure migratory birds (Letey et al. 2002; Ohlendorf 1986).