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Soil Microorganisms and Nematodes for Bioremediation and Amelioration

1.3.1.2.4 Phytoremediation

Phytoremediation is an efficient process, and it is cheap and environmental

friendly in the removal of heavy metal and toxic material from the soil. This

method requires the involvement of plant and their part which is supported

by the allied rhizospheric microorganism to extract and remove the pollutant

(Hooda, 2007). Generally, a heavy metal such as Cd, Se, and As is used to be

removed from the soil (contaminated soil) which are generally present in the

form of metal and metalloid (Hooda, 2007). This sustainable and inexpensive

process is evolving rapidly as a viable alternative to traditional remediation

approaches and would be the most acceptable for developing countries like

India. Despite this feasibility, phytoremediation has yet to become a potential

commercial technology available in India (Ghosh & Singh, 2005).

1.3.1.2.5 Subsurface Bioremediation

Bioremediation did at the subsurface region of soil where both organic and

inorganic pollutants. Ethylbenzene and xylenes (BTEX), benzene, toluene,

bioremediation is done by this method (Shim & Yang, 1999).

1.3.1.2.6 Free Enzyme Bioremediation

This is a newly developed technology allowing the rapid detoxification of

residues of pesticides in surface waters, such as irrigation water, and prob­

ably from other wettable products, such as soil and product surfaces (Scott

et al., 2011).

1.3.2 EX SITU BIOREMEDIATION

1.3.2.1 SOLID-PHASE SYSTEM

Composting is a method that involves the mixing of organic compounds

such as agricultural waste with polluted soil. The presence of the organic

material in the soil leads to the creation of a higher microbial population in

the soil which might lead to a higher compositing temperature (Shilev et al.,

2007). However, this method is a more controlled and extended version of

the land farming.