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ENVIRONMENTAL ENVIRONMENTAL POLLUTIONPOLLUTION
PollutionPollution• PollutionPollution is the introduction of is the introduction of contaminants into an contaminants into an
environmentenvironment that causes instability, disorder, harm or that causes instability, disorder, harm or discomfort to the discomfort to the ecosystem . .
Types of pollutionTypes of pollution
• Air pollutionAir pollution• Water pollutionWater pollution• Land or soil pollutionLand or soil pollution• Noise pollutionNoise pollution• Thermal pollutionThermal pollution• Marine pollution Marine pollution • Nuclear pollutionNuclear pollution
AIR POLLUTION
• Air pollution is the presence of contaminants in atmosphere in quantities such that it is injurious to human, plant animal life and property.
• Sources of air pollution :– Natural sources : Volcanic eruption, forest fires,
biological decay.– Manmade sources :thermal power plant ,fuel
burning, agriculture activities.
Classification of Air pollutants:
1.Primary air pollutants: CO,NO & SO2.
Emitted directly in the atmosphere.INDOOR AIR POLLUTANTS:
• Radon gas emitted from building materials like bricks,concrete,tiles etc.,
• It is present in natural gas and ground water.• burning of fuel in the kitchen,cigaratte, smoke.
2.Secondary air pollutants:HNO3,H2SO4
Primary pollutant may react with one another to form new pollutants.
Sulphur dioxide:• The combustion of sulphur containing fuels such as
coal and oil.• It can be converted into sulphuric acid.Human Sources :• Coal burning in power plant (88%)• Industrial processes (10%)• Environmental effects :• In humans : it causes eye irritation, cough, lung
diseases including lung cancer and asthma• In plants: it causes damage of leaves, bleaching of
chlorophyll which turns leaves brown, damage to crops and to growth of plants.
Oxides of nitrogen (NOx) Nitric oxide, nitrogen dioxide and nitrous oxide are
the three main oxides of nitrogen found in the atmosphere
Sources: The sources for the oxides of nitrogen are:• Bacterial decomposition of nitrogenous compounds• Combustion during lightning : During lightning, oxygen
and nitrogen in the atmosphere combine to give oxides of nitrogen.
• Industries and automobile exhaust - Air is sucked into the IC engines. At high temperatures, nitrogen and oxygen in the air combine to form nitric oxide.
Effects: The oxides of nitrogen combine with moisture
in the atmosphere to form nitrous and nitric acid. This leads to increase in the acidity of rain water.
Formation of photochemical smog: oxides of nitrogen combine with hydrocarbons present in the atmosphere forming peroxyacyl nitrate.
Control: Using catalytic converter in automobiles,
Catalytic converters use Pt/ Rh catalyst. the presence of these catalysts, the oxides of nitrogen are converted to nitrogen and oxygen .
2NOx ---- N2 + x O2
Carbon monoxide Sources:• Cigarette smoking,incomplete burning of fuels.• Automobile exhaust- carbon monoxide is formed
during the combustion of fuel such as petrol.(77%)• Industries: carbon monoxide is released by industries
such as iron and steel and petroleum . CO2 + C ------- 2CO
2CO2 --------- 2CO + O2
Effects:In humans:• When the atmosphere is polluted with carbon
monoxide, on inhalation, CO combines with the hemoglobin to form car boxy hemoglobin and hence oxygen carrying capacity of the blood decreases.
• This causes, headache, unconsciousness.• When inhaled for a long duration it may cause
even death.• In environment : it increase globe temp.
Lead pollutant:
Sources: The exhaust from automobiles which use lead
tetraethyl as antiknocking agent. Paint pigments : Litharge and red lead ( oxides of
lead ) and lead chromate are used as pigments. These cause lead pollution.
Effects:• It leads to anaemia and blood cancer in human
beings.• Lead enters the blood and various organs of the body
including the brain and the Kidneys leading to dysfunction of the kidney and damage to the brain.
Control of air pollution Source Control:• Use only unleaded petrol.• Use petroleum products and other fuels that have
low sulphur and ash content.• Reduce the no. of private vehicles• Ensure the houses, schools are not located on
busy streets.• Plant trees along busy streets to reduce
particulates, CO and noise.• Industries should be situated outside the city• Use catalytic converters to control CO
&hydrocarbons
Control measures in industries
• The emission rates should be restricted to permissible levels by industries.
• Air pollution control equipments must be made mandatory.
• Continuous monitoring of the atmosphere for the pollutants, to know the pollution levels.
EQUIPMENTS USED TO CONTROL AIR POLLUTION
• Use sufficient supply of oxygen in combustion chamber, so that the combustion is complete.
• Use mechanical devices such as scrubbers, cyclones, bag houses and electro-
static precipitators to reduce particulate pollutants
Electrostatic precipitator
Bag house filter/cyclone separator
Wet scrubber
WATER POLLUTION Any alteration in physical, chemical or
biological properties of water, as well as the addition of any foreign substance makes it unfit for health and which decreases the utility of water, is known as water pollution.
Definition of effluent: Liquid waste flowing out of a factory, farm, commercial establishment, or a household into a water body such as a river, lake, etc.,
Main sources of water pollution are:• Domestic and municipal sewage• Industrial waste• Agricultural waste• Radioactive materials, etc.,POINT AND NONPOINT SOURCES Two types of water pollutants exist; Point source Point sources of pollution occur when harmful
substances are emitted directly into water. e.g.,Oil spillNonpoint source. A non-point source delivers pollutants indirectly
through environmental changes. e.g., Fertilizer from a field is carried into a stream by
rain
Point SourcesPoint Sources
Non Point SourcesNon Point Sources
Types of pollutant:1.Infectious agents: Bacteria, viruses, protozoa
source : animal waste.Effect : variety of diseases
2.Oxygen demanding waste:Dissolved oxygen (DO) is the amount of oxygen dissolved in given quantity of water at a particular P and T. The saturation point 8-15mg/lit.
Sources: Sewage, paper waste, food processing waste.
Effects: affect to water quality, affect fish survival and migration.
3.Inorganic chemicals : Acids, pb, arsenic, selenium,sodium chloride and fluorides.Causes : surface runoff, effluents Effects: Cause skin cancer, damage nervous
system,harm to fish and aquatic life, lower crop yields.
4.Organic chemicals:Oil, gasoline,plastics, solvents ,detergents.Causes: Industrial efflents, surface runoff forms.Effects: Causing effect nervous system ,cancer, harm
fish and wild life.
5.Plant nutrients: Nitrate, phosphate and ammonium ionsCauses: sewage, runoff water from
agriculture,fertillizer.Effects: Excessive growth of algae, lower the oxygen
carrying capacity.
6.Sediment: Soil Causes: Land erosion. Effects: Can reduce photosynthesis, Affect aquatic
food webs.
Sewage treatment In primary treatment, the suspended solids
and floating objects are removed using coarse screens and sieves.
In secondary treatment, the maximum proportions of the suspended inorganic/ organic solids are removed from the liquid sewage. The liquid material passes into the sedimentation tank and finely suspended particles are allowed to settle by adding coagulants like Alum.
Tertiary treatment Remove detergents, metal ions, nitrates and
pesticides, as these are not removed in the earlier treatments.
The phosphates are removed as calcium phosphates by adding calcium hydroxide at pH 10-11. At this pH, ammonium salts are also converted into ammonia.
The effluent is chlorinated to remove pathogenic bacteria's and finally passed through activated charcoal to absorb gases.
Control of water pollution:
• Avoid Pesticides and fertilizers on sloped land areas.
• The nutrient rich water can be used as fertilizer in the fields.
• Separate drainage of sewage and rain water should be provided to prevent overflow of sewage with rain water.
• Planting more trees.
• Use nitrogen fixing plants to supplement the use of fertilizers.
SOIL POLLUTIONSOIL POLLUTION Soil pollution Soil pollution is caused by the presence of is caused by the presence of human-human-made chemicals or other alteration in the natural soil made chemicals or other alteration in the natural soil environmentenvironment..
This type of contamination typically arises from,This type of contamination typically arises from, • Application of Application of pesticides and and fertilizersfertilizers • Percolation of Percolation of contaminated surface water to contaminated surface water to
subsurface strata, oil and fuel dumping.subsurface strata, oil and fuel dumping.• Discharge of industrial wastes to the soilDischarge of industrial wastes to the soil. The most . The most
common chemicals involved are common chemicals involved are petroleum petroleum hydrocarbons, , solvents, pesticides, lead and other , pesticides, lead and other heavy metals. .
Effects of soil pollution:Effects of soil pollution:• Chronic exposure to Chronic exposure to chromium, lead and other chromium, lead and other
metals, petroleum, solventsmetals, petroleum, solvents, and many , and many pesticidepesticide and herbicide formulations can be and herbicide formulations can be carcinogeniccarcinogenic..
• Chronic exposure to Chronic exposure to benzenebenzene leads to leads to leukemialeukemia..(blood cancer)(blood cancer)
• Mercury and cyclodienes Mercury and cyclodienes are known to induce are known to induce higher incidences of higher incidences of kidney damage.kidney damage.
• Sewage sludge has many types of Sewage sludge has many types of bacteria, viruses bacteria, viruses and worms and worms which cause types of diseases and also which cause types of diseases and also emits toxic vapours.emits toxic vapours.
• Radioactive fallout cause abnormalities .eg., Radioactive fallout cause abnormalities .eg., Strontium-90Strontium-90 instead of calcium gets deposited instead of calcium gets deposited in the bones.in the bones.
• Soil contaminants can have significant Soil contaminants can have significant deleterious consequences for ecosystems.deleterious consequences for ecosystems.
• Effects occur to Effects occur to agricultural lands which have lands which have certain types of soil contamination.certain types of soil contamination.
• Alteration of Alteration of metabolism of endemic of endemic microorganisms..
• N & P N & P from fertilizer in soil reach water bodies from fertilizer in soil reach water bodies with agricultural runoff cause Eutrophication.with agricultural runoff cause Eutrophication.
• Chemicals contaminates ground water Chemicals contaminates ground water resources.resources.
• Acids, alkalis, heavy metals affect soil fertility.Acids, alkalis, heavy metals affect soil fertility.
Control of soil pollution :Control of soil pollution :• EffluentsEffluents should be properly should be properly treated treated before before
discharging on the soil.discharging on the soil.• Solid waste Solid waste should be properly collected and should be properly collected and
disposed off by appropriate method.disposed off by appropriate method.• From the waste, From the waste, recovery recovery of useful products of useful products
should be should be done.done.• Cattle dung Cattle dung should be used for should be used for methane methane
generation.generation.• Microbial degradation Microbial degradation of biodegradable of biodegradable
substance for substance for reducing soil pollutionreducing soil pollution..
NOISE POLLUTIONDefinition: Noise Pollution can be defied as unwanted or unpleasant sounds that causes discomfort for all living things.
• The various sources of noises are associated with urban development; road-air and rail transport; Industrial noise.
• In our country, indiscriminate use of loud speakers, generator sets and firecrackers has given new dimensions to the noise pollution problem.
• The commonly used parameter for noise is the sound level in decibel(dB). Human ears are sensitive in the frequency range of 20Hz to 20000Hz
Major Noise Sources: 1. Road Traffic: Road traffic noise is one of the most
widespread and growing environmental problems in urban area. The impact of road traffic noise on the community depends an various factors such as road location and design, land use planning measures, building design, Vehicle standards and deriver behavior. Motor vehicle ownership in India has increased substantially over the last 30 years and general levels of road traffic noise throughout India have increased through out the period.
2. Air Traffic: The extend of aircraft noise impact depends
on the type of aircraft flown, the number of flights and flight paths. The increase in number of flights, an important factor is overall noise levels, the led to an increase in general noise levels associated with air traffic.
3. Rail Traffic: The two main sources of noise and vibration
relating to the operation of the rail network is 1. The operation of trains and the maintenance 2. Construction of rail infrastructure.
4.Neighborhood & Domestic Noise:
Other significant source of noise annoyance is car alarms, building construction and household noise,Celebrations- religious function,social and elections.
5.Noise generated by noise levels of 125dB as per Environmental rules 1999.
Effects: 1. Noise can disturb out work, rest, sleep and
communication. 2. It can damage our hearing and evoke other
psychological, physiological and possibly pathological reactions.
3.It effects health efficiency and behaviour.It may cause damage to heart,brain,kidneys and liver.
4.It causes muscles to contract leading to nervous breakdown, tension.
5.Change in hormone content of blood, which turn increase the rate of heart beat.
6.Recently it has been reported that blood is also thickened by excessive noise.
7. Hearing damage : it can cause permanent hearing loss.
8.Interferences with man’s communication :In noise area communication is affected.
Sound Source Sound LeveldB
Subjective Feeling
of Human BeingsRockets and missiles,heavy explosives
160160 Unbearable
Jet Planes and cannons,explosives
140140 Unbearable
Aircraft Propeller andMachine Guns
130130 Unbearable
Diesel, steam engine andball mills, crackers
120120 Unbearable
Electric saws and looms,heavy trucks
110110 Unbearable
The CPCB-The central pollution control board recommended noise levels.
CONTROL MEASURES OF NOISE POLLUTION:1.REDUCTION IN SOURCE OF NOISE : Heavy vehicles and old
vehicles may not be allowed in populated areas.2. Noise making machines should be kept in containers
with sound absorbing media.3. Proper oiling will reduce the noise from the machinery.4. Use sound absorbing silencers: Silencers can reduce
noise by absorbing sound.5. Planting more trees having broad leaves.
6. Through law:sound production is minimized at various
social function.7. The use of fireworks or fire crackers shall not be
permitted except between 6.00a.m and 10.00p.m.No fireworks or fire crackers shall be used between 10.00p.m and 6.00a.m.
8. Silence zone in area comprising not less than 100meters around hospitals, educational institutions ,courts and religious places.
THERMAL POLLUTIONTHERMAL POLLUTION
• Energy is the basic necessity for the economic Energy is the basic necessity for the economic development of a countrydevelopment of a country. .
• The electrical energy is produced in power The electrical energy is produced in power plants or generating stations. The conventional plants or generating stations. The conventional power plants are:power plants are: - - Steam or Thermal Power station,Steam or Thermal Power station,
- Hydro-electric Power station, - Hydro-electric Power station,
- Nuclear Power station- Nuclear Power station
Steam or Thermal Power station In the thermal power station, In the thermal power station, the steam is the steam is
produced in the boiler, using the heat released produced in the boiler, using the heat released by the combustion of coal, oil or natural gas. by the combustion of coal, oil or natural gas.
The steam is used to The steam is used to rotate the steam rotate the steam turbine (impulse/ reaction).turbine (impulse/ reaction).
The steam turbine drives the alternator, The steam turbine drives the alternator, which which convertsconverts mechanical energy into mechanical energy into electrical energy.10-16electrical energy.10-16ooC C higher than initial higher than initial temp.temp.
Hydro-electric Power stationHydro-electric Power station • HydroelectricityHydroelectricity is the term referring to is the term referring to
electricity generated by electricity generated by hydropower..• The production of electrical power through the The production of electrical power through the
use of the gravitational force of falling or use of the gravitational force of falling or flowing water. flowing water.
• It is the most widely used form of It is the most widely used form of renewable energy. .
Once a hydroelectric complex is constructed, the Once a hydroelectric complex is constructed, the project produces no direct waste, and has a considerably project produces no direct waste, and has a considerably lower output level of the lower output level of the greenhouse gas & & carbon dioxide (CO (CO22).).
Nuclear Power station Nuclear powerNuclear power is produced by controlled is produced by controlled
(i.e., non-explosive) (i.e., non-explosive) nuclear reactions. . Commercial and utility plants currently use Commercial and utility plants currently use
nuclear fission reactions to heat water to reactions to heat water to produce produce steam, which is then used to generate , which is then used to generate electricity..
Effects of thermal pollutionEffects of thermal pollution• Elevated temperature typically decreases the Elevated temperature typically decreases the
level of level of dissolved oxygen (DO) in water. (DO) in water. • Thermal pollution may also increase the Thermal pollution may also increase the
metabolic rate of aquatic animals. rate of aquatic animals.• A large increase in temperature can lead to the A large increase in temperature can lead to the
denaturing of lifedenaturing of life.-barrier for oxygen penetration.-barrier for oxygen penetration into deep cold water. into deep cold water. • Fish migration Fish migration is affected due to formation of is affected due to formation of
various thermal zones.various thermal zones.• Discharge of Discharge of hot water hot water near the shores can be near the shores can be
disturb and even disturb and even kill young fisheskill young fishes..
• Toxicity of pesticides ,detergents and chemicals into the Toxicity of pesticides ,detergents and chemicals into the effluent increases with effluent increases with increase in tempincrease in temp..
• The composition of The composition of flora and fauna flora and fauna changes.changes.Control of thermal pollutionControl of thermal pollution• Thermal pollution from industrial sources is generated Thermal pollution from industrial sources is generated
mostly by mostly by power plantspower plants, , petroleum refineries, , pulp and paper mills, , chemical plants, , steel mills and and smelters..
• Cooling ponds, man-made bodies of water designed for , man-made bodies of water designed for cooling by cooling by evaporation, , convection, and radiation. , and radiation.
• Cooling towers, which transfer waste heat to the Cooling towers, which transfer waste heat to the atmosphere through evaporation and/or heat transfer.atmosphere through evaporation and/or heat transfer.
• Cogeneration, a process where waste heat is recycled Cogeneration, a process where waste heat is recycled for domestic and/or industrial heating purposes. for domestic and/or industrial heating purposes.
RADIO ACTIVE OR NUCLEAR POLLUTION
• The uncontrolled distribution of radioactive material in a given environment.
• Radioactive contamination is typically the result of a spill or accident during the production or use of radionuclide (radioisotopes), an unstable nucleus which has excessive energy.
• Contamination may occur from radioactive gases, liquids or particles
Effects • Radioactive contamination can enter the body
through ingestion, inhalation, absorption, or injection that causes discomfort, diarrhea, nausea or vomiting, and burns skin and hair loss.
• The cumulative damage can cause serious health problems long term, such as cancer, especially leukemia and Thyroid Cancer.
• For this reason, it is important to use personal protective equipment when working with radioactive materials.
Control methods:• It includes the stoppage of leakage from the
radioactive materials including the nuclear reactors, industries and laboratories.
• The disposal of radioactive material must be safe and secure.
• The protective garments must be worn by the workers who work in the nuclear plants.
• The natural radiation must be at the permissible limits and they must not cross it.
SOLID WASTE MANAGEMENT:Each household generates garbage or waste day in and day out. There are different types of solid waste depending on their source
Types of solid waste: Solid waste can be classified into different types depending on their source:Household waste is generally classified as,
• Municipal waste• Industrial waste as hazardous waste• Biomedical waste or hospital waste• E waste-Electronic waste
SOURCES OF URBAN AND INDUSTRIAL WASTE:• Waste from homes:polyethylene bags,Al
cans,glass bottles,waste paper,cloth,food waste,empty metal.
• Waste from shops:Cans,bottles,waste paper,tea leaves,packaging material.
• Biomedical waste : discarded medicines, chemical wastes, disposable syringes, swabs, bandages and body fluids.
• Construction waste :wood,concrete,cement .,
Industrial waste :Packaging meterial,organic waste, acid,alkali and metals.
• Solid waste: Rubber,plastic,paper,glass, wood,oils,paints, dyes,heavy metals, asbestos.Effects of solid waste :• Physicochemical and chemical characteristics
affecting productivity of soils.• Toxic substance contaminate the ground water.• Burning of materials produce dioxins, furans causes
cancer.
TYPES INVOLVED SOLID WASTE MANAGEMENT:1.REDUCE,REUSE,RECYCLE:a.Reduce the usage of raw materials: If usage is reduced,generation of waste also
reduced.b.Reuse of waste materials:1.Refillable containers can be reused2.Discarded cycle tubes can be made into rubber
rings.
c.Recycling of materials:1.Old Al cans and bottles are melted and recast
into new cans and bottles.2.Preparation of cellulose insulation from paper3.Preparation fuel pellets from kitchen waste.Methods of disposal of solid waste:a. Landfill : The bottom is covered with several layers of
clay,plastic & sand –protects ground water contamination.
• Landfill is covered with clay, sand & gravel.• Methane gas is collected and used to produce
electricity.b. Composting: The biodegradable waste is allowed to
decomposed into oxygen rich medium and quality rich environment is formed which improves soil fertility rate.
c. Incineration :Burning of waste at high temp(700oC -1000oC) in combustion chamber and used to produce electricity and incinerate100-150tonnes per hour.
Role of individual in prevention of pollution
Individuals can, however, play an important role in abatement of air, water, soil or noise pollution in the following simple manners: Use low-phosphate, phosphate-free or biodegradable dishwashing liquid, laundry detergent, and shampoo. Use manure or compost instead of commercial inorganic fertilizers to fertilize gardens and yard plant.
• Use biological methods or integrated pest management to control garden, yard, and household pests.
• Don't pour pesticides, paints, solvents, oils, or other products containing harmful chemicals down drain or on the ground.
• Recycle old motor oil and antifreeze at an auto service center that has an oil recycling program.
Test water for lead, nitrates, trihalomethanes, radon, volatile, organic compounds and pesticides.
Support ecological land-use planning in your community.
Get to know your local water bodies and form watchdog groups to help monitor and protect.
Flood
Flood Definition: Whenever the magnitude of water
flow exceeds the carrying capacity of the channel within its bank, the excess of water over flows on the surroundings causes floods.
Types: 1.Slow kinds: Runoff from sustained rainfall
2.Rapid snow melt exceeding the capacity of a river's channel.
3.Fast kinds: sudden release of water from dam, landslide, or glacier.
Effects1.Primary effects Physical damage – Can damage any type of
structure, including bridges, cars, buildings, sewerage systems, roadways, and canals.
2.Secondary effects• Water supplies – Contamination of water. Clean
drinking water becomes scarce.• Diseases – Unhygienic conditions. Spread of water-
borne diseases.• Crops and food supplies – Shortage of food crops can be caused due to loss of entire harvest. • Trees – Non-tolerant species can die from
suffocation.• Transport - Transport links destroyed.
Methods of control: Flood management:1.Diverting excess water through channel or canals
like river ,lake.2.Satelite pictures of preflood,flood and post flood
with other information.3.River networking .4.Optical and microwave data.5.Flood warning given by central water comission.
Cyclone
Definition:
A cyclone is an area of closed, circular fluid motion rotating in the same direction as the Earth.
• Most large-scale cyclonic circulations are centered on areas of low atmospheric pressure.
• Cyclones are powerful destructive and active from days to weak and speed varies 180-500km/hr.
• A broad area of low pressure rotating "counter-clockwise" (cyclonically) is also a cyclone.
Occurrence:
1.Tropical cyclone in the warm oceans are formed,
because of heat and moisture.
2. Sea surface temperature must below 25Oc .
3.It move like spinning top at the speed of 10-30km/hr.
4.Indian cyclone occurs during octo-dec or April – may.
Effects:• Tropical cyclones are responsible for large
amounts of damage to human life,crop,roads, transport, tanks wherever they strike. • Slow down the developmental activities of the
sea.Control:Damage can be reduced but not
completely prevented by doing the following: • Boarding up homes and businesses,
strategically placing sand bags, and building more wind resistant structures.
Cyclone management:• Satellite images are used by meteorological
department.• Radar system is used to detect the cyclone
and for cyclone warning.• For observing exact location of cyclone ,every
half an hour satellite picture are analyzed.• Its difficult to stop the formation of cyclone,
but the effect minimized by planting more trees.
Earthquake
• An earthquake is a sudden vibration caused on the earth’s surface due to the sudden release of tremendous amount of energy stored in the rocks under the earth’s crust.
Causes • Volcanic eruptions, rockfalls, landslides, and
explosions ,hydrostatic pressure of manmade water bodies.
• Under ground nuclear testing.• Decrease under ground water level.• Its measures by Richter scale. less than 4 – insignificant,4-4.9 – minor,5-5.9-
damaging,6-6.9 – destructive,7-7.9 – major,more than 8 – severe damage.
Effects• Earthquakes produce deformation of ground
space.• This includes damage to buildings and in worst
cases the loss of human life. • The effects of the rumbling produced by
earthquakes usually leads to the destruction of structures such as buildings, bridges, and dams.
• They can also trigger landslides.
Control:• To prevent an earthquake hazard the building
should be properly designed. • Do not construct houses on high risk prone
areas. • In case of an earthquake move out of the
building and came in the open but not panic. • Do not use lifts in case of an earthquake.
Tsunami Tsunami is a series of water waves caused by
the displacement of a large volume of a body of water, usually an ocean.
Causes :• Earth quake ,landslide• Deformation of the sea floor due to the
movement of plates.• Ordinary wave – 100,tsunami – 500km.• It travels across the deep sea at very high
velocity of at around 800-900km/hr.• Velocity decreases ,the height and energy of
wave increases.• Its height near the sea shore ranges from 15-
65m
Effects: The effects of the tsunami on the country during this period range from destruction damage, death, injury, millions of dollars in financial loss, and long lasting psychological problems for the inhabitants of the region.Tsunami management :
• Under the water are monitored by sensors.
• If any p changes, sensor send information.
•The information passed through earth stations.
•Warning system are warned of the danger approaching.
•Make the people alert through the media to take all
precautions.
Land slides Land slides are the process of large
differential movement of two land portion. OR
A landslide or landslip is a geological phenomenon which includes a wide range of ground movement.
Causes:• Down hill movement of earth cauesd by
rain,forces either increaing top materials.• Movement of heavy vehicles.• Earthquake ,shocks,vibrations,cyclone creates
landslides.• Erosion in the hilly tract due to runoff water.• Undergroung caves,underground mining
operation.
Effects• Property damage, • injury• death • adversely affect a variety of water supplies, • fisheries, • sewage disposal systems, • forests, dams, and roadways
Control• Soil Conservation: Ways to reduce soil erosion:Terracing: Terracing reduces soil erosion on steep slopes
by concerting the land into a series of broad, level terraces. This retains water for crops at each level and reduces soil erosion by water run off.
Contour Farming: This method is adopted for gently sloped land. This involves planting crops in rows across the contour of gently sloped land.
Agro forestry: In this method crops are planted together in strips or alleys between trees and shrubs that can provide fruits and fuel wood. The trees and shrubs provide shade which reduce water loss by evaporation and preserve soil moisture.
Wind Breaks : Wind breaks and shelter belts or trees are established to reduce wind erosion and also for retaining soil moisture
• Unloading the upper parts of the slope.• Concrete support.• Draining the surface and subsurface water from sloppy
region. • Soil stabilization by using quick lime in weak areas.
