Phytoremediation

Post-mining site at Okayama Prefecture of Japan

Phytoremediation is one of remediation technology that uses the plant to clean contaminated sites. The impact of Industrial Revolution introducing amount hazardous compounds into the environment. This hazardous pollutants consist of a variety of organic compounds and heavy metals, which pose serious risks to human health. Phytoremediation technique has developed because of it the low-cost application, natural cleanup technique methods using solar energy transport which are most useful at shallow sites, and low levels of contamination. The mechanisms of phytoremediation depend on the type of contaminant, bioavailability and soil properties. Primarily, the uptake of contaminants in plants occurs through the root system, which the principal mechanisms for preventing toxicity are found. In particularly mechanisms on phytoremediation are varied, including phytoextraction, rhizofiltration, phytovolatilization, phytostabilization, phytodegradation, hydraulic control, and rhizodegradation.

Phytoextraction also called phytoaccumulation, it refers to the uptake and translocation of metal contaminants in the soil by plant roots into the above-ground portions of the plants. This mechanism becomes primarily used for the contaminated soils treatment. Rhizofi
ltration is similar to phytoextraction, but the plants are used primarily to address contaminated ground water rather than soil. Phytovolatilization mechanism involves the use of plants to take up contaminants from the soil, transforming them into volatile forms and transpiring them into the atmosphere. Phytostabilization is the use of certain plant species to immobilize contaminants in the soil and ground water through absorption and accumulation by roots, adsorption onto roots, or precipitation within the root zone of plants (rhizosphere). Phytodegradation also referred to as phytotransformation. It involves the degradation of complex organic molecules to simple molecules or the incorporation of these molecules into plant tissues. In hydraulic control mechanism of groundwater contamination by plant canopies through increased transpiration reduces infiltration of precipitation or increases transpiration of groundwater, thus reducing contaminant migration from the site in groundwater plumes. The last scheme of phytoremediation mechanism is Rhizodegradation also referred to as phytostimulation refers to the breakdown of contaminants within the plant root zone or rhizosphere. It is believed to be carried out by bacteria or other microorganisms whose numbers typically flourish in the rhizosphere. It can also be seen as plant-assisted bioremediation, the stimulation of microbial and fungal degradation by the release of exudates/enzymes into the root zone (rhizosphere).