ABSTRACT
Phytoremediation has been proposed for a "green" biotechnology, facilitating the elimination of environmental pollutants from soil and sediments [1,2]. For the in situ treatment of contaminated surface soils, the use of vegetation appears to be a promising technology, offering ecologically stable bioremediation and soil restoration processes. Basically, this remediation approach depends on the sum of various rhizospheric effects of plants on microorganisms, soil, and contaminants. The rhizosphere, i.e., the soil colonized and influenced by the root system, provides conditions that, compared to bulk soil, lead to increased microbial populations and diversity [3]. For the biodegradation of rccalcitrant or xenobiotic compounds, it is supposed that release of root exudates is of primary significance for the microbial cometabolism of pollutants [4,5J.
