This document discusses phytoremediation, which uses plants to remove pollutants from the environment. It notes that increased population, industrialization, and urbanization have led to environmental contamination. Phytoremediation is a form of bioremediation that uses various plant-based mechanisms to contain contaminants in soils, groundwater, sediments, and air. These mechanisms include phytosequestration, phytodegradation, phytovolatilization, phytostabilization, and phytoextraction. The document provides details on each of these mechanisms and how plants can uptake and process various inorganic and organic contaminants.

1. Phytoremediation
• By- Dr. Kamini Roy
• Associate Professor, Agricultural
Chemistry and soil science,
• Lovely Professional University,
Phagwara
• (First ICAR Accredited University)
By Dr. Kamini Roy

2. Phytoremediation through
MPTs of soils
By Dr. Kamini
Roy

3. •Increased population, industrialization and urbanization are
responsible for environmental contamination. Environmental
decontamination is an enigma.
• However, advances in science and technology enabled us to
apply the potential of biological diversity for pollution
abatement which is termed as Bioremediation.
INTRODUCTION
By Dr. Kamini Roy

4. What is responsible for environmental
contamination.
• A. Increased population,
• B. industrialization and
• C. urbanization
• D. All of these
By Dr. Kamini
Roy

5. CONT...
• Bioremediation approach is currently applied to contain
contaminants in soil, groundwater, surface water, and
sediments including air.
• The scope of environmental bioremediation extends to:
Inorganics viz., Arsenic, Mercury, Chromium, Fluoride,
Cyanide, abandoned mines, fly ash disposed sites, biological
permeable barriers; and Organics viz., petroleum
hydrocarbons, pesticides and explosives.
By Dr. Kamini Roy

6. TYPES OF BIOREMEDIATION
IN-SITU :If the process occurs in the same place affected by pollution
then it is called in-situ bioremediation.
EX-SITU: deliberate relocation of the contaminated material (soil and
water) to a different place to accelerate biocatalysis is referred to as ex-
situ bioremediation.
By Dr. Kamini
Roy

7. Fate and transport of
organic/inorganic
contaminants/pollutants and
their harmful effects
By Dr. Kamini
Roy

8. By Dr. Kamini Roy

9. • Bioremediation approach is currently applied to
contain
• A. contaminants in soil,
• B. contaminants in groundwater and surface water,
• C. sediments including air.
• D. All of these
By Dr. Kamini
Roy

10. Phytosequestration
Phytochemical complexation in the root zone: Phytochemicals can be exuded
into the rhizosphere, leading to the precipitation or immobilization of target
contaminants in the root zone. This mechanism of phytosequestration may
reduce the fraction of the contaminant that is bioavailable.
Transport protein inhibition on the root membrane: Transport proteins
associated with the exterior root membrane can irreversibly bind and stabilize
contaminants on the root surfaces, preventing contaminants from entering the
plant. *
Vacuolar storage in the root cells: Transport proteins are also present that
facilitate transfer of contaminants between cells. However, plant cells contain a
compartment (the “vacuole”) that acts, in part, as a storage and waste
receptacle for the plant. Contaminants can be sequestered into the vacuoles of
root cells, preventing further translocation to the xylem.
By Dr. Kamini Roy

11. Phytodegradation
It refers to the uptake of contaminants with the subsequent breakdown,
mineralization, or metabolization by the plant itself through various internal
enzymatic reactions and metabolic processes.
Plants catalyze several internal reactions by producing enzymes with various
activities and functions . Specifically, oxygenases have been identified in plants
that are able to address hydrocarbons such as aliphatic and aromatic
compounds.
Similarly, nitroreductases are produced in some plants that can reduce and
breakdown energetic compounds such as the explosives trinitrotoluene (TNT),
1, 3, 5- trinitroperhydro -1, 3, 5- triazine (RDX) and ,3,5,7- tetranitro -1,3,5,7-
tetrazocine (HMX High melting explosive)
By Dr. Kamini Roy

12. By Dr. Kamini Roy

13. Phytovolatilization
It is the volatilization of contaminants from the plant either from the
leaf stomata or from plant stems.
Chemical characteristics such as the, Henry’s constant, and vapor
pressure dictate the ability of organic contaminants to volatilize.
Certain inorganic constituents such as mercury may be volatilized as
well. Specifically, tobacco plants have been modified to be able to
take up the highly toxic methyl-mercury, alter the chemical
speciation, and phytovolatilize relatively safe levels of the less toxic
elemental mercury into the atmosphere
By Dr. Kamini
Roy

14. Phytostabilization
Phytostabilization refers to the holding of contaminated soils and sediments
in place by vegetation, and to immobilizing toxic contaminants in soils.
Establishment of rooted vegetation prevents windblown dust, an important
pathway for human exposure at hazardous waste sites.
Phytostabilization is especially applicable for metal contaminants at waste
sites where the best alternative is often to hold contaminants in place.
Metals do not ultimately degrade, so capturing them in situ is the best
alternative at sites with low contamination levels (below risk thresholds) or
vast contaminated areas where a large-scale removal action or other in situ
remediation is not feasible. By Dr. Kamini Roy

15. CONTT....
Phytostabilization covers provide a natural barrier and resistance to
erosion and leaching and can be further used to minimize non-point
source (NPS) pollution if the soil or sediment is impacted.
By Dr. Kamini Roy

16. CONTT...
In addition to the ability of cover systems to stabilize soil/sediment and
control hydraulics, densely rooted groundcover plants and grasses can
also be used in bioremediation.
The typical range of effectiveness for phytoremediation groundcovers is
30-60 cms below ground surface; however, depths down to 1.5 meters
have been reported as within the range of influence under some
situations.
By Dr. Kamini Roy

17. Phytoextraction refers to the ability of plants to take up contaminants
into the roots and translocate them to the aboveground shoots or
leaves. For contaminants to be extracted by plants, the constituent
must be dissolved in the soil water and come into contact with the
plant roots through the transpiration stream.
By Dr. Kamini Roy

18. CONTT..
Certain plants called “hyper accumulators” absorb unusually large amounts
of metals in comparison to other plants and the ambient metal concentration.
Some halophytes in tropical and near tropical environments such as salt
cedars take up saline water and exude the excess salt through the stomata
back onto the ground as a means to create the niche.
some plants may produce and exude specific phytochemicals directly into the
soil environment that alter the chemistry and speciation of constituents to
promote the mobilization and uptake into the plant, particularly for
enhancing the uptake of essential nutrients through the release of acidic
phytochemicals.
By Dr. Kamini Roy

19. Acknowledge and Thanks
Author is immensely thankful to all the websites and books
whom I contacted to make these slides more informative and
attractive
By Dr. Kamini Roy

20. WE SHALL OVERCOME
Stay healthy
By Dr. Kamini Roy