Areas near smelters and sewage sludge dumps. The ideal plant used for phytoextraction should have high biomass, a high metal bioaccumulation factor and a high metal tolerance. In contrast, the adequate plant species for phytostabilization should have the characteristics of tolerance to high levels of the metal, a profuse root system, a rapid growth rate and a high biomass in the field
In response to the high metal concentration in the environment, plants would adopt one of these strategy, i.e.,accumulation or exclusion, to cope with excess metal. These plants may be called accumulators and excluders. Many attempts have been made to identify their tolerance and metal accumulation characteristics.