2. Ecological effects of soil pollution
and it’s management
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SIDDU MALAKANNAVAR
PGS17AGR7312
Ph.D. Scholar
DEPARTMENT OF
AGRONOMY
UAS, Dharwad
3. CONTENTS
Soil pollution
Causes of soil pollution
Types of soil pollution
Effects of soil pollution
Control of soil pollution
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4. soil pollution:
Any undesirable changes in the physical, chemical or
biological properties of the soil which is harmful to
environment, living organisms and plants is called ‘‘soil
pollution’’.
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5. Soil Pollution: Global Scenario
• Russia, China and India are among the countries in the world where pollution
of toxic land is spreading rapidly.
• Chernobyl in Ukraine is remembered for the world’s largest nuclear power
accident millions of acres of agricultural land are damaged
• China’s Linfen City’s land has been polluted due to excessive coal mining and
pollution of toxic chemicals like arsenic in the soil.
• Worlds largest chromite mines in Sukinda of Odisha in India, the lives of the
people in this city has become jeopardized.
• Worlds largest chromite mines in Sukinda of Odisha in India, the lives of the
people in this city has become jeopardized.
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6. • In a study conducted in Uttarakhand (2011) where earlier average four
bags of urea were used that has increased to 10 bags.
• According to Global E-Waste Monitoring, United Nations report
released in 2015, India is at the fifth place in the world in spreading e-
waste.
• The Ministry of Forests of the Government of India estimates that
about 47 percent of total area of India is cultivated on agriculture, of
which approximately 56-57 percent of the fertile strength has
decreased.
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7. Causes of soil pollution ….
Use of chemicals:
pesticides, insecticides, fertilizers
Excessive use of these chemical increases salinity of soil
It adversely affects the microorganisms present in it causing soil to lose its
fertility
use of organic chemicals in the last thirty years has increased by more than 11
times. In India alone every year, there is a use of approximately 100,000
tonnes of biochemicals.
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8. Causes of soil pollution ….
Soil erosion:
Deforestation
• It occurs when top soil moves from
one place to a other as a reasult of
various natural and man made
factors
• Leads to decrease in soils capacity to
retain water
• When the soil is eroded, crops are
effected resulting in an indiredct
effect on environment
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9. Causes of soil pollution ….
Salty water
• Use of water with high salinity cause
soil pollution
• Salts present in water accumulates
at the top layer of the soil
• This salty water present in soil
becomes a cause for studded growth
of the crops.
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10. • Causes of soil pollution ….
Urban waste
• Both commercial and domestic
wastes consisting of dried sludge and
sewage.
• It consists of garbage and rubbish
materials like plastics, glasses,
metallic cans, fibres, paper, rubbers,
street sweepings etc
• As rain water runs from top of this
uncovered garbage cause the soil
pollution
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11. Causes of soil pollution ….
Industrial wastes
• Most of industrial waste rejected materials like calcium, magnisium, sulphates
etc.
• Fly ash is a major source of pollution surrounding the industrial area.
• This industrial waste dumped over the soil surface by almost all industries
• This causes toxicity of soil.
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12. Causes of soil pollution ….
Pollution of underground waste
• Deposition of many agricultural chemicals in the underground layers has
disturbed the normal activities.
• Living of earthworms, centipede, millipede, frogs and rats underground has
greatly disturbed the ecological equilibrium.
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13. • Causes of soil pollution ….
Radioactive waste
Radio nuclides of Radium, Thorium, Uranium, isotopes of Potassium (K-40)
and Carbon (C-14) are commonly found in soil, rock, water and air.
Explosion of hydrogen weapons and cosmic radiations include neutron,
proton reactions by which Nitrogen (N-15) produces C-14. This C-14
participates in Carbon metabolism of plants which is then into animals and
human beings.
Radioactive waste contains several radio nuclides such as Strontium90,
Iodine-129, Cesium-137 and isotopes of Iron which are most injurious.
Strontium get deposited in bones and tissues instead of calcium.
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14. Nuclear reactors produce waste containing Ruthenium-106, Iodine-
131, Barium-140, Cesium-144 and Lanthanum-140 along with
primary nuclides Sr-90 with a half life 28 years and Cs-137 with a
half life 30 years.
Rain water carries Sr-90 and Cs-137 to be deposited on the soil
where they are held firmly with the soil particles by electrostatic
forces. All the radio nuclides deposited on the soil emit gamma
radiations.
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15. Causes of soil pollution ….
Waste from mining
Huge holes are dug in the ground waste obtained from mining left on site
in the form of soil heaps
The waste contain toxic and poisonous substances which then leach into
the soil due to rainfall
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16. Causes of soil pollution ….
Leakage of toxins
• Faulty landfills
• Bursting of underground bins
• Seepage from faulty sewage systems.
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17. Causes of soil pollution ….
Oil and petroleum spills
Petroleum spills from gas stations, fuel tanks or other activities can reasult in
elivated levels of contaminants in the soil.
Such as benzene, toluene and xylene.
Oil spills cause poor growth of plants.
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18. Effects soil pollution
• Endangering Human Health
• More than 70% of the soil pollutants are carcinogenic in
nature intensifying the chances of developing cancer in the
humans
• Long-term exposure to benzene and polychlorinated
biphenyls (PCBs) linked to the development of leukemia and
liver cancer
• Causes skin diseases, muscular blockage, and central nervous
system disorders.
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19. • Humans can be affected indirectly due to bioaccumulation or
food poisoning.
• High concentrations of lead and mercury in the soil caused
kidney, liver damage and hamper brain development in
children.
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20. Economic Losses
Heavily polluted soils with metals and chemicals such as lead, asbestos, and
sulfur are unfavorable for crop production and cannot be used to grow crops.
According to China’s agricultural sector about 12 million tons of polluted
grains are subjected to disposal on an annual basis, costing Chinese farmers
economic losses of up to 2.6 billion U.S. dollars.
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21. Air and Water contamination
• Polluted soil discharging volatile compounds into the atmosphere.
So, the more toxic contaminants in the soil, the higher the level of
toxic particles and foul gasses emitted into the atmosphere.
• Soil pollution can also lead to water pollution if the toxic chemicals
and materials like dangerous heavy metals leach into groundwater
which reaches lakes, rivers, streams, or oceans.
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22. Effect on Plant Life:
Soil pollutants interfere with soil chemistry, biology, and structure.
Benefcial soil bacteria, soil microorganisms, soil nutrients, and soil
chemical processes begin to deteriorate to an extent where they diminish
soil fertility.
The ecological balance is lost completely. On this basis, the soil becomes
unsuitable
If the plants die, then animals dependent on the plants will also die. This
leads to migration of the larger animals and predators to other regions
Soil pollution can as well change plant metabolism and lower crop
productivity.
When plants take up the soil contaminants, they pass them up the food
chain, endangering the health of animals and humans this process is called
bio magnifcation and is a serious threat to the ecology.
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23. • Acidification
Soil pollution allows emission of relatively large quantities of nitrogen via
denitrifcation, volatilization of ammonia, and the decomposition of organic
materials in the soil. As a result, this releases sulfur compounds and sulfur
dioxides into the atmosphere, causing acid rain.
Acidic conditions hinder soil ability to cushion, changes in the soil PH,
leading to the death of plants
Changes in the Soil Structure
Increase in Soil Salinity
• Irrigation and agricultural processes that discharge nitrate and phosphate
deposits in the soil are the primary contributors to increasing salt levels in
the soil.
• Difficult for plants to absorb soil moisture and reduces groundwater quality.
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24. Control measures of soil pollution:
• 3 Rs: reduce, reuse, recycle
• The sewage sludge from the factories should be treated before reaching the
ground
• Priority should be given to the waste deposition by the Municipality and the
Municipal bodies
• Reduce the use of chemical fertilizers
• The best way to reduce the use of these chemicals and reduce soil pollution is
by organic farming
• The use of insecticides, fungicides, and herbivorous etc should be minimized
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25. • Prevent the flow of garbage in rivers
• The formulation and implementation of the schemes required to
protect the land which is destroyed by foods
• Controlled grazing and forest management
• Wind breaks and wind shield in areas exposed to wind erosion
• Afforestation and reforestation
• Ban on Toxic chemicals
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26. • Bioremediation:
• Biostimulation: To stimulate the activity of microorganisms by
adding nutrients and electron acceptors (e.g. O2)
• Bioventing: Injecting air through soil to stimulate microbe
growth in unsaturated zone
• Biosparging: Injection of air/nutrients into unsaturated and
saturated zones
• Bioaugmentation: inoculation of soil with microbes or adding
exogenous microbes to the subsurface
34. Laws of soil pollution
There is no specific legislation which deals with regulation of
soil pollution.
Unlike air pollution and water pollution there is no perfect
direct law which deals with soil pollution. Unlike,
environmental protection act act (EPA) which deals with all
aspects of environment.
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