such as stem and leaves that can be harvested and finally burnt to gain energy and
recovery as well as recycle of absorbed metals from the ash (Erakhrumen 2017).
Phytostabilization
Phytostabilization is the most suited method for soil, sludge and sediment. It
involves the basic concept that specific chemicals produced by the plants; in place
of their degradation immobilize the contaminants. This is an effective way to prevent
relocation of contaminants to groundwater or their entry into food chain
(Cunningham et al. 1996). In this method, plants act as an impediment of percolation
of water within the soil. Sorption, precipitation, reduction in metal valence etc. are
the important properties of this method which is mainly used to treat metals like Cu,
Zn, Cr, As and Cd (Kunito et al. 2001). By this method one can prevent movement of
contaminants, it is best suited for preserving and restoring our soil and valuable
Ground water resources. It is the safest option to clean the environment as it does not
interfere with the natural obstruct environment. The disadvantage of this method is
that movement of metals like contaminants is restricted but they continue to stay in
the soil (Zeng et al. 2018).
Rhizofiltration
The roots play major role in this method and it makes usage of plants to ad/absorb the
pollutants. Thus, it restricts movement of heavy metals like pollutant in groundwater. Aquatic plants with long fibrous root systems can be used in rhizofiltration since
pH change in the rhizosphere as well as exudate from roots Pbs to precipitation of
heavy metals onto the root surface. This can be productively used for various
industrial effluents, radioactive contaminants and metals. Change or alteration of
pH in the rhizospheric zone and exudates from root helps the heavy metal precipitation on the root surface the (Raskin and Ensley 2000).
Phytovolatilization
In this method, plants after absorbing a contaminant converts into a volatile compound and then transpire them into surrounding atmosphere through stomata and
other transpiring surfaces. This method is more suited for plants like Brassica napus
and Brassica juncea are appropriate species for the phytovolatilization of Se. Hg and
Se are the Heavy metals that can be readily remediated by phytovolatilization
process (Karami and Shamsuddin 2010).
Plants have also evolved highly specific mechanisms to translocate and store
micronutrients. These same mechanisms are also involved in the uptake, translocation, and storage of toxic elements, whose chemical properties simulate those of
essential elements. Plants possess and use a variety of mechanisms to deal with the
contaminations especially heavy metals, hydrocarbon compounds and man –made
chemicals such as herbicides, fungicides, pesticides. Plants sequester them in their
cell walls. Plants chelate these contaminations in the soil in inactive forms or
complex those in their tissues and can store them in vacuoles, away from the
sensitive cell cytoplasm where most metabolic processes occur. Organics may be
degraded in the root zone depending on their properties of plants or taken up,
followed by degradation, sequestration, or volatilization. TEC which is the most
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P. Parikh and K. Unadkat
recovery as well as recycle of absorbed metals from the ash (Erakhrumen 2017).
Phytostabilization
Phytostabilization is the most suited method for soil, sludge and sediment. It
involves the basic concept that specific chemicals produced by the plants; in place
of their degradation immobilize the contaminants. This is an effective way to prevent
relocation of contaminants to groundwater or their entry into food chain
(Cunningham et al. 1996). In this method, plants act as an impediment of percolation
of water within the soil. Sorption, precipitation, reduction in metal valence etc. are
the important properties of this method which is mainly used to treat metals like Cu,
Zn, Cr, As and Cd (Kunito et al. 2001). By this method one can prevent movement of
contaminants, it is best suited for preserving and restoring our soil and valuable
Ground water resources. It is the safest option to clean the environment as it does not
interfere with the natural obstruct environment. The disadvantage of this method is
that movement of metals like contaminants is restricted but they continue to stay in
the soil (Zeng et al. 2018).
Rhizofiltration
The roots play major role in this method and it makes usage of plants to ad/absorb the
pollutants. Thus, it restricts movement of heavy metals like pollutant in groundwater. Aquatic plants with long fibrous root systems can be used in rhizofiltration since
pH change in the rhizosphere as well as exudate from roots Pbs to precipitation of
heavy metals onto the root surface. This can be productively used for various
industrial effluents, radioactive contaminants and metals. Change or alteration of
pH in the rhizospheric zone and exudates from root helps the heavy metal precipitation on the root surface the (Raskin and Ensley 2000).
Phytovolatilization
In this method, plants after absorbing a contaminant converts into a volatile compound and then transpire them into surrounding atmosphere through stomata and
other transpiring surfaces. This method is more suited for plants like Brassica napus
and Brassica juncea are appropriate species for the phytovolatilization of Se. Hg and
Se are the Heavy metals that can be readily remediated by phytovolatilization
process (Karami and Shamsuddin 2010).
Plants have also evolved highly specific mechanisms to translocate and store
micronutrients. These same mechanisms are also involved in the uptake, translocation, and storage of toxic elements, whose chemical properties simulate those of
essential elements. Plants possess and use a variety of mechanisms to deal with the
contaminations especially heavy metals, hydrocarbon compounds and man –made
chemicals such as herbicides, fungicides, pesticides. Plants sequester them in their
cell walls. Plants chelate these contaminations in the soil in inactive forms or
complex those in their tissues and can store them in vacuoles, away from the
sensitive cell cytoplasm where most metabolic processes occur. Organics may be
degraded in the root zone depending on their properties of plants or taken up,
followed by degradation, sequestration, or volatilization. TEC which is the most
326
P. Parikh and K. Unadkat