BIOAVAILABILITY OF ELEMENTS FOR EFFECTIVE PHYTOREMEDIATION AND PHYTOMINING: THE ROLE OF RHIZOSPHERE PROCESSES

Abstract

The success of phytoremediation (especially phytoextraction) and phytomining depends heavily on the bioavailability of target elements, which, among others, is a function of soil mineral phases, soil organic matter, pH and redox potential. The use of soil additives which, e.g., change soil pH or increase the amount of chelating compounds, has been propagated in the past in order to desorb the target elements from the soil matrix. These additives, however, may have negative environmental consequences by causing leaching of toxic elements from the soil due to enhanced mobility in the soil solution. For this reason less dangerous alternatives are necessary which use the natural capacity of plants to increase availability of target elements in their root environment.