Under wetland system, soil and local microorganisms affect
removal potential. Microorganisms can also enhance in the phytoremediation system. These microbes can be contaminant degraders and/or can promote plant growth under stress. DGGE, a culture-independent genetic
fingerprinting technique, is a faster method for describing microbial community structure and diversity in environmental samples,
either at a gross taxonomic level or at a more refined, e.g. genus level. The major advantage of this technique is that it allows the direct determination of microbial genetic diversity. However, this does not exclude the latter techniques from identifying the key microorganisms