8.5.2 Biomineralization/Biocrystallization
In this technique, microbes generate the ligands which cause the precipitation of
heavy metals as biomass-bound crystalline deposits.
8.5.3 Biostimulation
Biostimulation technique includes the stimulation of the indigenous microbes
present in the contaminated soil by employing the necessary nutrients required.
Necessary nutrients may supply through the mineral application as well in the
form of manure, compost, etc.
8.5.4 Bioattenuation
This technique includes monitoring the process of natural degradation to ensure the
decrease of the contaminant with time at the relevant sampling point is done.
8.5.5 Bioventing
It is an in situ bioremediation technique which is a relatively passive technique. In
this method oxygen is supllied to the soil in order to stimulate aerobic soil microbial
growth and degradation activity. It works for simple hydrocarbons and can be used
where the contamination is deep under the surface (Vidali 2001). The monitoring
difficulty is there (Zaidi et al. 2012).
8.5.6 Biofilters
Biofilters technique includes the use of microbial stripping columns to treat air
emissions. The microbes generally break the toxic substances into a non-toxic
compound e.g., carbon dioxide (CO 2 ), water (H 2 O), and salts.
8.5.7 Bioreactors
This process involves the use of a container/reactor for the treatment of the liquid or
slurries. The advantage of the bioreactors is rapid degradation kinetics, optimized
8 Bioremediation of Polluted Soil by Using Plant Growth–Promoting Rhizobacteria
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In this technique, microbes generate the ligands which cause the precipitation of
heavy metals as biomass-bound crystalline deposits.
8.5.3 Biostimulation
Biostimulation technique includes the stimulation of the indigenous microbes
present in the contaminated soil by employing the necessary nutrients required.
Necessary nutrients may supply through the mineral application as well in the
form of manure, compost, etc.
8.5.4 Bioattenuation
This technique includes monitoring the process of natural degradation to ensure the
decrease of the contaminant with time at the relevant sampling point is done.
8.5.5 Bioventing
It is an in situ bioremediation technique which is a relatively passive technique. In
this method oxygen is supllied to the soil in order to stimulate aerobic soil microbial
growth and degradation activity. It works for simple hydrocarbons and can be used
where the contamination is deep under the surface (Vidali 2001). The monitoring
difficulty is there (Zaidi et al. 2012).
8.5.6 Biofilters
Biofilters technique includes the use of microbial stripping columns to treat air
emissions. The microbes generally break the toxic substances into a non-toxic
compound e.g., carbon dioxide (CO 2 ), water (H 2 O), and salts.
8.5.7 Bioreactors
This process involves the use of a container/reactor for the treatment of the liquid or
slurries. The advantage of the bioreactors is rapid degradation kinetics, optimized
8 Bioremediation of Polluted Soil by Using Plant Growth–Promoting Rhizobacteria
209