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taken to the flora wherein its miles replaced in place of their water. Those plants are then

planted in a grimy location where the roots take in water and dust in conjunction with it. As
the roots fill with dust, they are harvested.

Sunflower, Indian mustard, tobacco, rye, spinach, and maize are the plants that have been
tested to dispose of lead from water (Smith et al. 1997). Rhizofiltration is a cost-effective era

for treating floor water or groundwater containing low, but crucial concentrations of heavy
metals including Cr, Pb, and Zn (Hamlin 2002)

PHYTOVOLATILIZATION: This system involves the usage of vegetation to choose up

contaminants inside the soil, then convert the metals into vapour forms and the transpiration
of those metals is done by means of plant leaves leaving the surroundings. Toxic metals along

with Se, As and Hg may be bio methylated to molecules that can be lost in environment.

Phytovolatilization might also involve the spread of contaminants from the stems or other
parts of the plant to which the contaminants travels before accomplishing the leaves (Smith et

al. 1997) and (Hamlin 2002).
Brassica juncea and Arabidopsis thaliana plant convert inorganic Se into natural

selenoaminoacids (selenomethionine and selenocysteine) followed by biomethylation to form
dimethyl selenide or dimethyl diselenide flexible and non-risky for the environment (Khalid

etal 2017). This technique reduces the entry of Se into the food chain, because most of the Se

get volatilised below ground in the roots (Zayed and Terry 1994)
PHYTOSTABILIZATION: It is the process of immobilisation of heavy metals by plants in

the soil. Plants absorb heavy metals through roots, accumulate them, and precipitate them in
the root zone, in this way metals get stabilized in the soil (US EPA 2000)..This method

reduces the flexibility or movement of heavy metals within the ground. This technique
reasons the metals to stagnate in the soil matrix main to a reduction in soil bioavailability.

Metallic Immobilization can be carried out by decreasing airborne dirt, through decreasing

soil erosion, and by way of lowering the melting of contaminants or the presence of
bioavailability in the meals chain. With the addition of soil supplements, such as organic

remember, alkalizing retailers, phosphates and biosolids lessen the melting of metals within

the soil and reduce leakage in groundwater. , easy to apply, and gives aesthetic value (Ghosh
and Singh 2005).

At phytostabilization, it's miles highly recommended to apply extracts that allow heavy
metals from the soil to penetrate simplest to their roots, protective their aerial additives from

contamination with those metals. Such metallophyte species are the Agrostis tenius and
Festuca rubra vegetation used for phytostabilization of soil contaminated with Pb, Zn and Cu

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