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MANNAM FOUNDATION CENTRE FOR
EDUCATION TECHNOLOGY
PORUVAZHY, EDAKKAD P.O.,
KOLLAM
ONLINE ASSIGNMENT
SUBMITTED TO: SUBMITTED BY:
RINTU CHACKO Name : AKHILA K NADH
Optional : NATURAL SCIENCE
Reg. No : 18114373002
SUBMITTED ON : 28/10/2015
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INDEX
1. Topic : 3
2. Introduction : 4-5
3. Deforestation : 6
4. Causes of Deforestation : 7 - 9
5. Impacts of Deforestation : 10-12
6. Measures to control or check
Deforestation : 13
7. Conclusion : 14
8. Reference : 15
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TOPIC:
DEFORESTATION
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INTRODUCTION
Forests are the dominant terrestrial ecosystem of earth. A forest is a large
area of land covered with trees or other woody vegetation. According to
environmental science, 25% of a country’s land area should be covered with
forests for a balanced ecology. Now a days deforestation is a serious problem.
Deforestation means the indiscriminate removal/destruction of the forest
cover or the vegetation of an area. It includes repeated lopping, felling,
annual removal of forest litter, browsing, grazing and trampling of seedlings.
Anthropogenic destruction of forests (deforestation) began thousands of
years ago. The initial needs for fuel wood and construction materials
continued to increase as populations expanded. With the progress in
industrialization, mining, grazing, commercial plantation and urbanization the
indiscriminate felling of trees and denudation of forests continued with
accelerated pace. Construction of dams and hydroelectric projects also
contributed to the large scale destruction of forests, over the years much of
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the original forest cover disappeared due to clear felling and large scale
destruction mainly for making land for cultivation.
In ancient India, the tree was regarded as sacred, and the forest was a place
of pilgrimage. The artists give even greater significance to the tree. They
believe that the tree gifted art to mankind. The flute, the drum, the lute, the
pen- all comes from the tree. For the philosophers of ancient India the forest
was a symbol of an idealized cosmos. They found the forest to be self
sufficient and regenerative. Despite the importance of trees, today trees are
being cut down at a disastrous pace. Much of the Himalayan forest has been
already destroyed. The forests of India are the cradle of Indian civilization.
Every attempt has therefore to be made to preserve our trees and forests.
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DEFORESTATION
Deforestation (clearance/clearing) is the removal of a forest or stand of trees
where the land is thereafter converted to a non-forest use. “Deforestation
refers to the cutting, clearing and removal of rainforest or related ecosystems
into less bio- diverse ecosystems such as pasture, cropland or plantations”
(Kricher, 1997). Examples of deforestation include conversion of forestland to
farms, ranches or urban use. In temperate mesic climates, natural
regeneration of forest stands often will not occur in the absence of
disturbance, whether natural or anthropogenic.
Deforestation is actually the destruction of biotic potential of land that leads
to a formidable threat to the economy, quality of life and future of the
environment. According to a global estimate, forests have dwindled from
about 7,000 million hectares in 1900 to 2890 million hectares in 1975. In the
year 2000, only about 2370 million hectares are left. Tropical rain forest,
which incidentally are the most productive forests in the world, have been the
worst affected. These have been reduced from 1600 million hectares to 938
million hectares. At the time of independence the country had 75 million
hectors under forest cover. This comprised about 22% of our total area. Today
this has been reduced to just over 10% against the minimum requirement of
33%. India has been losing 10 million trees every 24 hours. The entire
Himalayan ecosystem is threatened and under severe imbalance as perennial
springs have dried u owing to devastation of forests, Kerala has lost not less
than half of the forests it had at the time of its formation in 1956.
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CAUSES OF DEFORESTATION
The following are the main causes of Deforestation
Agricultural practices: Land under forest coverage is converted into
agricultural land and used for cultivating crops. As the land is cleared
for agriculture, biomass is burned, and the resultant ash enriches the
soil. Without protecting layer of tree cover, the heavy downpours fall
on the bare soil. This leads to soil erosion and nutrients are flushed
away into rivers and out to the sea. Besides that, the decreasing
amount of organic matter in the soil and loss of vegetation cover
binding the soil also reduce the moisture retention capacity of the soil
considerably. Moreover, nutrient depletion also occurs due to the
cultivation and harvest of two or three crops.
Development projects: The scientific and technological advancements
had their impact on the forests. Development projects like the
hydroelectric projects, large dams and reservoirs, lying down of railway
lines and roads, establishment of industries, etc. are linked with several
environmental problems. Many of these projects require immense
deforestation. Infrastructural facilities like buildings, townships, electric
supply, etc. necessitate clearing the land. The forest products are used
on a large scale in the implementation of this project themselves.
Deforestation begins much before the actual commissioning of the
projects and continues even after the completion of the project.
Fuel requirements: the increasing demand for fuel wood is one of the
major factors leading to the degradation of the forest ecosystem. Fuel
wood is of such major importance that about one-half of all the wood
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cut in the world is used for lighting, cooking or heating purposes. Even
today more than one third of humanity. Still relies on wood for fuel. In
the recent years, the oil crisis and the sharp increase in the prices of oil
have further escalated the demand for wood as fuel. The increasing
demand for firewood with every passing year means greater pressures
on the forests, which also means increased intensity of deforestation.
Raw materials for industry: Wood is not only used as fuel, but it also
has a variety of other uses, it is used for making boxes, crates, and
packing cases, match boxes , furniture, paper and plywood. Paper
industry consumes about 2 per cent of the country’s annual
consumption of wood. A major share of raw material for paper industry
comes from bamboo. This exerted tremendous pressure on the
bamboo plantations of the country. Packing cases made of ply wood
are used extensively in several industries. Softwood of various types
from forests or plantations is used for this purpose. Industries that
manufacture drugs, scents and perfumes, resin, gums, waxes,
turpentine, latex and rubber, tannis, alkaloids, bees’ wax, all obtain
their raw materials from plants, exerting tremendous pressure on
plants, ultimately leading to their destruction. Thus, a large number of
industries are dependent on forests. The thoughtless and unrestricted
exploitation of forest for various raw materials is the main cause of
degradation of the forest eco system.
Other Causes: Floods and forest fires have a devastating effect on the
forests. Very often, forest fires are caused by the deliberate burning of
trees by poachers and smugglers. Natural enemies like termites, pests
and several kinds of diseases affect the forests adversely. Defense
activities like preparation of ditches and bunkers movement of heavy
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armoury and their use also affect the forest ecosystem considerably.
Major wars fought in the past have resulted in untold damage to
the forest ecosystems. The best example for this kind of destruction is
the Vietnam War. During the war period (1962-71), about 71 million
liters’ of defoliant chemicals were sprayed over the coast, which
resulted in the destruction of 1, 04,000 hectares of mangrove forest.
In addition to the above causes, deforestation also results from
overgrazing, agriculture, mining and urbanization.
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IMPACTS OF DEFORESTATION
Forests are the most important natural resource on our planet upon
which the living beings, especially the human beings rely for their
existence. Deforestation would definitely deprive the man of the
economic benefits and environmental quality enjoyed by him from
nature. Large scale deforestation if continued unabated, will lead to
dangerous consequences, which will threaten the normal existence of
man on earth. Some of the adverse effects of deforestation are the
following:
Reduction of food and space for wild life: The deforestation has
resulted in drastic reduction of the habitable space and food of
wild animals. This leads to gradual decrease in the population and
ultimate extinction of several species of animals. Species
extinction may lead to severe ecological imbalance.
Imbalance in atmosphere: Since green plants remove CO2 from
the air and add O2 during photosynthesis, decrease in vegetation
causes increase in CO2 and decrease in O2 concentration of
atmosphere. This tipping the balance in favour of CO2 creates a
grave situation for living beings. Increase in CO2 concentration
tends to make the atmosphere very hot leading to severe
consequences.
Soil erosion: When vegetation becomes scanty, the root system
will not form a tight network in the soil. As a result the soil
becomes loose. It can be easily washed away by wind and flowing
waters. As a result of deep massive soil erosion, extensive systems
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of gullies, called ravines are formed. Forests with deep-rooted
trees resist soil erosion and land slide.
Flood: In the absence of trees atmosphere becomes hot and
humus formation becomes adequate. As a result, the top soil
becomes loose, dry and hard, with only poor powers of absorbing
water. Consequently, most of the rain water flows away, causing
flash floods and soil erosion.
Silting of rivers and reservoirs: Extensive flood and soil erosion
consequent on deforestation result in washing away of large
amounts of topsoil. The fertile soil thus removed gets deposited in
rivers, canals and reservoirs of dams. This results in the
overflowing of rivers and canals on flooding and reduction in the
capacity of the dams.
Humidity, temperature and rainfall: Deforestation causes a
decrease in humidity, an increase in atmospheric temperature
and a reduction in rainfall. Trees increase humidity and thereby
make the atmosphere cool. In fact the evapo-transpiration from
the plants has a moderating effect on precipitation. Deforestation
naturally decreases humidity and renders atmosphere hot and
this in turn results in decreased rainfall.
Water resources: Deforestation reduces surface water and
ground water resources. In the denuded land, as the run off
increases, water percolation into the soil decreases. It results in
reduction of water resources available during dry season.
Reduction in soil fertility: Reduction in humus formation and
washing away of the topsoil due to increased soil erosion result in
the reduction of soil fertility.
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Desertification: Increase in CO2 concentration and decrease in
humidity and rainfall bring about adverse climatic changes. In the
long run the entire area may turn into an arid land or at the
extreme a desert. Thus, deforestation may ultimately lead to
desertification.
Deforestation leads to scarcity of food, fuel and other requirements of
the native people. This forces them to migrate to the nearby urban
areas. This migration causes over-population in the urban areas and
hereby undue stress on the urban environment.
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MEASURES TO CONTROL OR CHECK DEFORESTATION
1. People should not be allowed to cut young and healthy trees
2. Afforestation or planting more and more trees on waste land and hill
slopes.
3. People should be educated to concentrate on other sources of energy
other than fuel wood.
4. People should be educated against the hazards of deforestation.
5. People should not be allowed to throw burning match sticks, cigarettes
and beedies in the forest areas.
6. Forest Protection Force should be fully trained and equipped with latest
technology to check deforestation.
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CONCLUSION
Deforestation is the permanent destruction of forests in order to make the
land available for other uses. Deforestation occurs around the world. There
are many causes of deforestation. Some reasons are: to make more land
available for housing and urbanization, to harvest timber to create
commercial items such as paper, furniture and homes, to create room for
cattle ranching …etc. These tactics leave the land completely barren and are
controversial practices. Clear cutting is when large swaths of land are cut
down all at once. A forestry expert quoted by the Natural Resources Defense
Counsil describes clear cutting as “an ecological trauma that has no precedent
in nature”. Deforestation is considered to be one of the contributing factors
to global climate change. Eco forestry, Green business, Land use planning
Community forestry etc can be applicable as remedial measures.
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REFERENCES
1. Ecology, Ethology, Evolution, Zoogeography; K Vijayakumaran
Nair, M Jayaprakash, Meera George ; Academica publishers;
Pageno:150-153.
2. https://en.m.wikipedia.org/wiki/Deforestation
3. http://ayazraina.wikispaces.com/Measures+to+control+Deforest
ation.
4. https://ronzusgreenworld.wordpress.cm/disasers-and-
controls/assignment-on-deforestation/
5. http://science.howstuffworks.com/environmental/green-
sciencce/deforestation3.htm