ENVIRONMENTAL
MANAGEMENT
Introduction
·
Environmental management deals
with the different aspects of environment, its structure, function, its quality
and its maintenance including conservation of its living and non-living
components.
·
The diversified natural resources
on this earth provide the necessities for survival of all forms of life
including man.
·
Resources can be renewed
simultaneously along with their exploitation (forests, crops, wildlife,
groundwater, wind and solar energy).
·
Continuous increase in population
caused an increased demand for resources.
·
Therefore, conservation of
natural resources makes important contributions to the social and economic development
of the country.
Conservation
and Judicious Use of Resources
·
The use of natural resources in
excess and unplanned way leads to imbalance in the environment.
·
A judicious balance should be
maintained between exploitation of resources and its replenishment.
·
Proper utilization and management
of nature and its resources is termed as conservation.
·
We have to build a sustainable world,
which should last forever.
·
It is important that we manage
and use our resources carefully so as to preserve for the future generations.
Forest and its
Importance
Deforestation
·
Deforestation is the destruction
of large area of forests.
·
This happens for many reasons
like intensive agriculture, urbanization, construction of dams, roads,
buildings and industries, hydroelectric projects, forest fires, construction of
mountain and forest roads.
·
It is a threat to the economy,
quality of life and future of the environment. India is losing about 1.5
million hectares of forest cover every year.
Effects of
Deforestation
·
Deforestation gives rise to
ecological problems like floods, drought, soil erosion, loss of wild life,
extinction of species, imbalance of biogeochemical cycles, alteration of
climatic conditions and desertification.
Conservation of
Forests
·
The important measures taken for
conservation of forests are as follows
Afforestation
·
Activities for afforestation
programme (Van Mahotsav) includes planting and protecting trees with multiple
uses which help in restoration of green cover.
·
Destruction of trees should be
curtailed.
Social forestry programme
·
It should be undertaken on a
large scale with active participation of the public and utilization of common
land to produce firewood, fodder and timber for the benefit of the rural
community.
·
This relieves pressure on
existing forests and to safeguard future of tribals.
Forest Conservation through Laws
·
Adopting stringent laws and
policies to conserve and protect forests are through National Forest Policy,
(1952 and 1988) and Forest Conservation Act, 1980.
Wildlife and
its Conservation
·
Wild life refers to the
undomesticated animals living in their natural habitats (forests, grasslands
and deserts) an area without human habitation.
·
They are needed for maintaining
biological diversity.
·
Conservation of forest and
wildlife is interrelated with each other.
Decline in Wildlife Population
·
Wildlife of India is a great
natural heritage.
·
Exploitation of wildlife
resources has decreased global wildlife population by 52% between 1970 and
2014.
·
Over exploitation and shrinking
of forest cover areas has resulted in animals becoming extinct, some are
threatened and some are on the verge of extinction.
·
In recent years, increase in
human encroachment has posed a threat to India’s wildlife.
Aims of Wildlife Management
The main
aim of wildlife conservation are:
v To control and limit exploitation of species.
v To
preserve the plants and animals from extinction.
v Maintenance of threatened species and protect
species which are on the verge of extinction.
v Preserve the endangered species.
v To study the ecological relationship of the
plants and animals in natural habitat.
v Hunting and poaching should be prohibited.
v Establishment
of National parks, Wildlife sanctuaries, protected areas and Biosphere reserves.
The Wildlife protection Act was established in
1972. The provisions of the act are
v Prohibit
killing and hunting of specified animals.
v Constitute
sanctuaries, national parks, and closed areas for wildlife conservation.
v Special
schemes for preservation of endangered species.
v Constitute
Central Zoo Authority and recognition of zoos.
v Restrict,
regulate or prohibit trade in wild animals and products obtained from them.
Organisations Involved in
Conservation of Wildlife
(i) Indian Board for WildLife (IBWL)
(ii) World Wildlife Fund (WWF) for Nature
(iii) World
Conservation Union (WCN)
(iv)
International Union for Conservation of Nature and Natural resources (IUCN)
(v)
Convention of International Trade in Endangered Species (CITES)
(vi) Bombay
Natural History Society
(vii) Wild
life Preservation Society of India, Dehradun
Soil Erosion
•
The top layers of soil contain
humus and mineral salts, which are vital for the growth of plants.
•
Removal of upper layer of soil by
wind and water is called soil erosion.
•
Soil erosion causes a significant
loss of humus, nutrients and decrease the fertility of soil.
Agents of Soil Erosion
Agents of soil erosion are high velocity of wind,
air currents, flowing water, landslide, human activities (deforestation,
farming and mining) and overgrazing by cattle.
Management of Soil Erosion
•
Retain vegetation cover, so that
soil is not exposed.
•
Cattle grazing should be controlled.
•
Crop rotation and soil management
improve soil organic matter.
•
Runoff water should be stored in
the catchment.
•
Reforestation, terracing and
contour ploughing.
•
Wind speed can be controlled by planting trees
in form of a shelter belt.
Renewable and
Non-Renewable Energy Resources
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Renewable Resources |
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Non-Renewable Resources |
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Fossil Fuels
•
Fossil fuels are found inside the
earth’s crust and are energy rich substances formed by natural process, such as
anaerobic decomposition of buried dead organisms, over millions of years.
•
As the accumulating sediment
layers produce heat and pressure, the remains of the organisms are gradually
transformed into hydrocarbons.
•
e.g. petroleum, coal and natural
gas.
Coal and Petroleum
•
Coal and Petroleum are natural
resources. They are called fossil fuels as they are formed from the degradation
of biomass buried deep under the earth millions of years ago.
•
Coal is used for generation of
electricity at Thermal power plants.
•
Petroleum also known as crude oil
is processed in oil refineries to produce petrol and diesel which are used to
run automobiles, trucks, trains, ships and airplanes etc.
•
Kerosene and LPG (Liquefied
Petroleum Gas) obtained from petroleum is used as domestic fuel for cooking
food.
•
The formation of these fossil
fuels is a very slow process and takes very long period of time for renewal.
Steps to
Conserve Coal and Petroleum Resources
v It
is necessary to conserve or save coal and petroleum resources for the future
use, which can be done by reducing their consumption.
(i) If
electricity is saved, it will inturn reduce the use of coal.
(ii) Using
bicycle for covering short distances instead of using cars, scooters or motorcycles.
(iii) Using
pressure cooker can reduce the consumption of kerosene and LPG while cooking
food. Solar cooker and solar heaters can be used wherever possible.
(iv)Motor vehicles should be designed with fuel
efficient engines to increase efficiency and also reduce air pollution.
Non-Conventional
(Alternative) Energy Resources
v The
energy crisis has shown that for sustainable development in energy sector we
must conserve the non-renewable conventional resources from its rapid depletion
and replace them by non-polluting, renewable sources which are environmentally
clean.
v Efforts
are made to develop new sources of energy which is called non-conventional
sources of energy.
Solar Energy
v Solar
energy is the energy obtained from the sun.
v The
sun gives out vast amount of light and heat. It is only a little less than half
(47%) of solar energy which falls on the atmosphere reaches the earth’s
surface.
v The
energy from the sun can be harnessed to provide power. The various devices used
for harnessing sun’s energy are called solar energy devices.
Solar Cells
•
Solar cells (Photovoltaic
devices) is made up of silicon that converts sunlight directly into
electricity.
•
Solar cell produces electricity
without polluting the environment.
•
These can be installed in remote
and inacessible areas (forests and hilly regions) where setting up of power
plant is expensive.
Uses of Solar cells
(i) It can be used for street lighting, traffic
signals, water pumping, battery charging system etc.
(ii) It is used in artificial satellites and space
probes
(iii) It
provides radio and TV transmission to remote areas
(iv) It is used in calculators, electronic toys
and watches.
Solar Panel
Arrangement of many solar cells side by side
connected to each other is called solar panel. The capacity to provide electric
current is much increased in the solar panel. But the process of manufacture is
very expensive.
Solar Cooker
It consist of an insulated metal box or wooden box
which is painted from inside so as to absorb maximum solar radiations. A thick
glass sheet forms the cover over the box. The reflector is the plane mirror
which is attached to the box. The food is cooked by energy radiated by
the sun.
Solar thermal power plant
In solar thermal power plants, many solar panels
are used to concentrate sun rays, to heat up water into steam. The steam is
used to run the turbines to produce electricity.
Advantages of Solar Energy
(i) It is available in abundance in our country
and is free of cost.
(ii) It is
a renewable source of energy.
(iii) It
can be used for generating electricity or heat.
(iv) It
does not cause pollution.
Biogas
Biogas is the mixture of methane (nearly 75 %),
hydrogen sulphide, carbon dioxide and hydrogen.
It is produced by the decomposition of animal
wastes (cow dung) and plant wastes in the absence of oxygen. It is also
commonly called as ‘Gobar gas’ since the starting material used is cow dung
which means gobar in Hindi.
Uses of biogas
(i) It is used as fuel for cooking .
(ii) It is
used to run motors and pump sets.
(iii) It is used to generate electricity.
Advantages of biogas
(i) It burns without smoke and therefore causes
less pollution.
(ii) An excellent way to get rid of organic wastes
like bio-waste and sewage material.
(iii) Left
over slurry is a good manure rich in nitrogen and phosphorus
(iv)It is
safe and convenient to use
(v) It can reduce the amount of greenhouse gases
emitted.
Shale gas
Shale refers to the soft finely stratified sedimentary
rock that is formed from the compaction of small old rocks containing mud and
minerals – such as quartz and calcite, trapped beneath earth’s surface. These
rocks contain fossil fuels like oil and gas in their pores. The fuel is
extracted by a technique called hydraulic fracturing (drilling or well boring
of sedimentary rocks layers to reach productive reservoir layers).
Wind Energy
The kinetic energy possessed by the wind is due to
its high speed, that can be converted into mechanical power by wind turbines.
The wind energy can be used for (i) generating electricity (ii) Run water
pumps, flour mills etc. (iii) Rotatory motion of windmill is used to draw water
from wells.
Windmill
Windmill is a machine that converts the energy of
wind into rotational energy by broad blade attached to the rotating axis.
The rotational movement of the blades operate the
generator and the electricity is produced.
The energy output from each windmill is coupled
together to get electricity on a commercial scale.
Advantages of Wind energy
(i) Wind energy is free, eco-friendly, renewable
source of energy.
(ii) It does not cause pollution.
(iii)
Expenses on periodic maintenance is low when compared to the other power
sources.
Water Energy
Earth’s surface is covered with nearly 71% of
water. Harnessing the energy from the flowing water can be used to produce electricity.
The technique to harness the water energy is called Hydropower.
Hydropower plants converts the kinetic energy of
flowing water into electricity. This is called hydroelectricity.
Tidal Energy
Tidal energy is the energy obtained from the
movement of water due to ocean tides. Tides are the rise and fall of sea levels
caused by the combined effects of the gravitational forces exerted on the
oceans of the earth.
Advantages of tidal energy
(i) Tidal energy does not produce any pollution.
(ii) It does not use any fuel and does not produce
any waste.
(iii) Tides
are predictable, so tidal energy can be produced at any time.
(iv) Water
is denser than air and therefore can generate electricity at lower speeds than
wind turbines.
Rainwater
Harvesting
Rainwater harvesting is a technique of collecting
and storing rainwater for future use. It is a traditional method of storing
rain water in underground tanks, ponds, lakes, check dams and used in future.
The main purpose of rainwater harvesting is to
make the rainwater percolate under the ground so as to recharge ‘groundwater
level’.
Electrical
Energy Management
Electricity or electric power is produced by
generators. The generators are operated by the turbines attached to it. The
turbines are rotated by steam, moving water or wind power to produce
electricity.
Conservation of electrical energy
The following measures can be taken even at home
and school to save electricity
(i) Use energy efficient appliances to save
electricity like Compact Fluorescent Lamps (CFL), Light Emiting Diode (LED)
bulbs and other electric equipments.
(ii) Switch
off the lights and fans, television and other electrical appliances when not in
use.
(iii)
Switch of the mobile phone chargers when not in use.
(iv) Maximise the use of solar radiation. Solar
water heating system can be used instead of electric geysers.
(v) Minimise the use of air conditioners.
E-Wastes and
its Management
E-wastes are generally called as electronic
wastes, which includes the spoiled, outdated, non-repairable electrical and
electronic devices. These wastes contain toxic metals like lead, cadmium,
chromium and mercury, though also contain iron, copper, silicon, aluminum and
gold which can be recovered.
Sources of
e-wastes
Electronic devices:
Computers,
laptops, mobile phones, printers, monitors, televisions, DVD players,
calculators, toys, sport equipments, etc.
Household electrical appliances:
Refrigerators, washing machine, microwave oven,
mixer, grinder, water heater, etc.
Accessories:
Printing
cartridges, batteries and chargers.
Environmental impact of e-wastes :
Disposal of any kind of electrical and electronic
devices without knowledge can become the landfill and water pollutants.
Electronic equipments contain many hazardous heavy metals such as lead, cadmium
that can cause severe soil and groundwater pollution.
Sewage
Management
Untreated sewage or wastewater generated from
domestic and industrial process is the leading polluter of water sources in
India. Sewage water results in agricultural contamination and environmental
degradation.
Sources of Sewage/wastewater
•
Domestic purpose or household
activities
•
Dye and textile industries
•
Leather industries
•
Sugar and breweries industries
•
Paper and pulp industries
The conventional wastewater treatment methods
involve the following steps
(a)
Pre-screening (b) Aeration (c) Sludge Management and (d) Water Reuse.
Pre-screening: Wastewater generated from domestic
and industrial activities is screened to remove soil and solid particulates.
Aeration:
Screened wastewater is then pumped to an aeration tank. Here the microbial
contaminants are removed by the biological degradation that occurs in the
presence of air. Sedimentation process: In this process, the solid particles in
suspension form are allowed to settle. The particles that settle out from the
suspension is known as sludge.
Sludge removal: The sludge generated by the
degradation process is transferred periodically from the tank for safe
disposal.
Disinfection: Chlorination and ultraviolet (UV)
radiation of treated water is required to remove any microorganism
contamination.
Water recycling:
The water will then be supplied for domestic or industrial purposes.
Solid Waste
Management
Methods of solid wastes disposal
(i) Segregation: It is the separation of different
type of waste materials like biodegradable and non biodegradable wastes.
(ii) Sanitary landfill:
Solid wastes are dumped into low lying areas. The layers are compacted by
trucks to allow settlement. The waste materials get stabilised in about 2-12
months. The organic matter undergoes decomposition.
(iii) Incineration:
It is the burning of nonbiodegradable solid wastes (medical wastes) in properly
constructed furnace at high temperature.
(iv)Composting: Biodegradable matter of solid wastes
is digested by microbial action or earthworms and converted into humus.
3R Approach
The 3R
approach such as Reduce, Reuse and Recycle may be followed for effective waste
management.