6.3.2.3 Biological Method
Microorganisms (MO) and plants are used to degrade harmful contaminants, and this
process called biological treatments. The beneficial effect of plant roots is dual:
firstly—root execrations can provide energy for microorganisms, secondly—the
presence of roots can alter the physical and chemical conditions in polluted soil in
a manner that promotes microbial degradation (Malachowska-Jutsz and Kalka
2010).
But the above two techniques, physical and chemical methods, of bioremediation
have some limitation or other side effect on environment. The selection of any
method might rely upon the form of pollutant to be remediated, the proposed use
of the contaminated area, required time periods and money (Chibuike 2013). But
biological method is a unique system used for the elimination and/or recovery of
contaminant from spoiled environments. The technique utilizes microorganisms and
plants, or their products, to recover spoiled environments to their original condition
(Tak et al. 2013; Mani and Kumar 2014). These methods are eco-friendly and cheap
for the elimination/recovery of toxic metal, when compared to the conventional
chemical and physical techniques, which are often more costly and unsuccessful,
especially for low metal concentrations (Akcil et al. 2015; Verma and Verma 2016).
6.4 Importance of Biological Method
Biotechnology has amazing capability to cater for the need and holds hope for
environmental safety, sustainability, and manageable (Hatti-Kaul et al. 2007;
Azadi 2010). Therefore, bioremediation and phytoremediation are also an application of biotechnology (Koenigsberg et al. 2005). Because, they are able to metabolize, immobilize, or absorb toxic compounds from the surrounding. However,
principal benefits of systems are that they are much less dangerous to surroundings
with minimum or no through-products (Dowling and Doty 2009).
Hyperaccumulators are plants that are able to accumulate, degrade, or render less
poisonous pollutants present in ecosystem such as soils, water, and air.
Bioaccumulation of Cs was observed by Lasat et al. (1998). In case of bioremediation, the consortia or microbial (bacteria and fungi) processes are used to degrade
and detoxify environmental toxins (Dixit et al. 2015; M’rassi et al. 2015). This
method has been used for decontamination of different horizon of soils and different
types of water body (freshwater and marine) (Baker et al. 1994). It has positive
effects upon soil composition and fertility. Another biological method of heavy
metal removal is phytoremediation. Plants are used in phytoremediation techniques
to remove, sequester, and/or detoxify toxic from polluted soil (Meagher 2003;
Raskin et al. 1997). The method is completely cost-effective, green technology,
and efficiently eliminate contaminants like metals, hydrocarbons, and chlorinated
6 VAM: An Alternate Strategy for Bioremediation of Polluted Environment
163
Microorganisms (MO) and plants are used to degrade harmful contaminants, and this
process called biological treatments. The beneficial effect of plant roots is dual:
firstly—root execrations can provide energy for microorganisms, secondly—the
presence of roots can alter the physical and chemical conditions in polluted soil in
a manner that promotes microbial degradation (Malachowska-Jutsz and Kalka
2010).
But the above two techniques, physical and chemical methods, of bioremediation
have some limitation or other side effect on environment. The selection of any
method might rely upon the form of pollutant to be remediated, the proposed use
of the contaminated area, required time periods and money (Chibuike 2013). But
biological method is a unique system used for the elimination and/or recovery of
contaminant from spoiled environments. The technique utilizes microorganisms and
plants, or their products, to recover spoiled environments to their original condition
(Tak et al. 2013; Mani and Kumar 2014). These methods are eco-friendly and cheap
for the elimination/recovery of toxic metal, when compared to the conventional
chemical and physical techniques, which are often more costly and unsuccessful,
especially for low metal concentrations (Akcil et al. 2015; Verma and Verma 2016).
6.4 Importance of Biological Method
Biotechnology has amazing capability to cater for the need and holds hope for
environmental safety, sustainability, and manageable (Hatti-Kaul et al. 2007;
Azadi 2010). Therefore, bioremediation and phytoremediation are also an application of biotechnology (Koenigsberg et al. 2005). Because, they are able to metabolize, immobilize, or absorb toxic compounds from the surrounding. However,
principal benefits of systems are that they are much less dangerous to surroundings
with minimum or no through-products (Dowling and Doty 2009).
Hyperaccumulators are plants that are able to accumulate, degrade, or render less
poisonous pollutants present in ecosystem such as soils, water, and air.
Bioaccumulation of Cs was observed by Lasat et al. (1998). In case of bioremediation, the consortia or microbial (bacteria and fungi) processes are used to degrade
and detoxify environmental toxins (Dixit et al. 2015; M’rassi et al. 2015). This
method has been used for decontamination of different horizon of soils and different
types of water body (freshwater and marine) (Baker et al. 1994). It has positive
effects upon soil composition and fertility. Another biological method of heavy
metal removal is phytoremediation. Plants are used in phytoremediation techniques
to remove, sequester, and/or detoxify toxic from polluted soil (Meagher 2003;
Raskin et al. 1997). The method is completely cost-effective, green technology,
and efficiently eliminate contaminants like metals, hydrocarbons, and chlorinated
6 VAM: An Alternate Strategy for Bioremediation of Polluted Environment
163