2 - Environmental Resources
-
Upload
aneeshajaiswal -
Category
Documents
-
view
212 -
download
0
Transcript of 2 - Environmental Resources
-
7/30/2019 2 - Environmental Resources
1/10
LESSON 2
ENVIRONMENTAL RESOURCES
INTRODUCTION: Forests are natural renewable resources to the mankind on planet
earth. The total forest cover of the country has been estimated to be 19.39% of the
geographical area. Forests comprise mainly trees which provide wood that may be
converted into solid, liquid, and gaseous fuels. They are important for the climate of the
Earth, they act as filters of carbon dioxide, they are habitats and shelters to millions of
species, and they are also important for their aesthetic appeal. Forests provide raw
material for various wood-based industries, viz., pulp and paper, composite wood, rayon
and other man-made fibers, sport goods, furniture, boat building, matches etc. Timber is
an important material in building construction. Miscellaneous products, like bamboos,
resins, gums, some oils, fibers, medicines, katha, lac, shellac etc. are obtained from
forests.
CONTENTS
IntroductionUses of forestsFunctions of forestsDeforestationCauses of deforestationEffect of deforestation on tribal people
Dams and forestsDisplacement of people by miningReferencesSelf Evaluation
-
7/30/2019 2 - Environmental Resources
2/10
The forest cover of the country has
been estimated to be 637,293 Sq.Km.
which is 19.39% of the geographic area
of the country. The dense forest, open
forest and mangrove constitute 11.48%,
7.76% and 0.15% of the geographic area
respectively.
USESOFFORESTS:
Uses are broadly classified into three categories:
1. Protective functions: These include the protective role of forests against soil
erosion, droughts, floods, intense radiation.
2. Productive functions: Forests are the source of wood and many other products
like gums, resins, fibres, medicines, katha, honey, bidi wrappers, pulp, paper.
3. Accessory functions: These include the role of forests in recreation, aesthetics,
and as habitat of diverse wildlife.
FUNCTIONSOFFORESTS:
Atmospheric regulation:
- Absorption of solar heat during evapo-transpiration
- Maintaining carbon dioxide levels for plant growth
-
Maintaining the local climatic conditions
Water shed production:
- Reducing the rate of surface run-off of water
- Preventing flash floods and soil erosion
-
7/30/2019 2 - Environmental Resources
3/10
- Producing prolonged gradual run off and thus safeguarding against drought.
Erosion control: Holding soil by preventing rain from directly washing soil away.
Land bank: Maintaining soil nutrients and structure
Local use(consumptive use):
- Food: gathering plants, fishing, hunting from the forest
- Fodder for cattle
- Fuel wood and charcoal for cooking and heating
- Poles for building homes especially in rural and wilderness areas
- Timber for household articles and construction
- Fiber for weaving baskets, ropes, nets, string etc.
- Sericulture for silk
- Apiculture or rearing bees for honey
- Medicinal plants for traditional medicines
Market use (Productive use)
- Most of the above forest products are sold as a source of income for supporting
the livelihoods of forest-dwelling people- Minor forest produce like fuel wood, fruit, gum, fiber etc., which are collected and
sold in local markets as a source of income for forest dwellers
- Major timber extraction for construction, industrial uses, paper pulp etc.
DEFORESTATION:
Deforestation is the permanent destruction of
indigenous forests and wood lands. One of the
serious environmental problems is forest degradation
due to timber extraction and dependence on fuel
wood. Trees on our planet are being depleted at a
very fast rate.
-
7/30/2019 2 - Environmental Resources
4/10
Although humans have been practicing deforestation since ages, it was in the
mid-1800s that forests began to be destroyed at an unprecedented rate According to
some estimates, more than 50 percent of the tree cover has disappeared due to human
activity.
One of the most worrying factors today is the massive destruction of the rainforests of
the world, which is affecting the biodiversity adversely.
Over the last half century, forests have been subjected to overexploitation,
degradation and encroachment due to several reasons:
- Collection of firewood and charcoal
- Overgrazing and long traveling distances
-Construction of dams and roads
- Forest fires
- Mangrove felling for building materials
- Farming and agriculture
- Mining
- Urbanization, industrialization, population growth
- Poverty illicit trade
- Certain government policies
CAUSESOFDEFORESTATION:
The destruction of the forests is occurring
due to various reasons, one of the main
reasons being the short term economic benefits.
Given below are some more common causes of
deforestation:
Used for Urban and Construction
Purposes: The cutting down of trees for
lumber that is used for building materials, furniture, and paper products. Forests
are also cleared in order to accommodate expanding urban areas.
-
7/30/2019 2 - Environmental Resources
5/10
To Grow Crops: Forests are also cut down in order to clear land for growing
crops.
To Create Grazing Land: Forests are cut down in order to create land for
grazing cattle.
Used for Fuel: Trees are cut down in developing countries to be used as
firewood or turned into charcoal, which are used for cooking and heating
purposes.
Some of the other causes of deforestation are: clearing forests for oil and mining
exploitation; to make highways and roads; slash and burn farming techniques; wildfires;
and acid rain.
EFFECTOFDEFORESTATIONONTRIBALPEOPLE
One person out of every 20 on earth belongs to indigenous cultures found in
about 70 countries. Many of earths tribal peoples, representing 5,000 cultures, are
vanishing as their lands are taken for economic development. Large dams are being
constructed on environmentally sensitive sites, as in the Himalayas, or in heavily
forested areas, and are creating more ecological problems in the long term and
displacing large tribal population. Silent valley and Bedthi projects have already been
given up by the Kerala and Karnataka governments respectively due to anti-dam
campaigns.
DAMSAND FORESTS
The forest is being cleared for approach
roads, offices, and residential quarters and forstorage of construction material due to the
construction of dams. With the reduction in forest
cover and the entry of people, the pressure on the
remaining forest increases. Their need for
-
7/30/2019 2 - Environmental Resources
6/10
firewood leads to further denudation. There is a recurring loss in terms of timber and
firewood yield per year and degradation of environment.
Case study:
182 villages in Madhya Pradesh will be affected due to the construction of
reservoir while dam is in Gujarat. 60 to 80 thousand people will be displaced. It is
believed that larger areas of Gujarat will be irrigated and many more thousands of
people will be benefited by Sardar Sarovar dam. But people of Madhya Pradesh had to
make sacrifices out of which many of them are ancient tribals.
DISPLACEMENTOFPEOPLEBYMINING:
Most mining work leads to water and air pollution, despoliation of land and
deforestation, noise and ground vibration problems etc. Mining operations affected
forest and cultivated land areas mainly in U.P., Bihar, M.P., Orissa and A.P. The use of
land on large scale for townships, communication, excavation and transport affected the
socioeconomic and geology of these areas.
REFERENCES:
1. Surinder Deswal and Anupama Deswal, 2002, Energy Ecology, Environment
and Society, Dhanpat Rai and Company, New Delhi, pp-8.21
2. P.D. Sharma , 1996, Ecology and Environment, Rastogi Publications,
Meerut , (New Delhi), pp-326
SELF EVALUATION:
FILL IN THE BLANKS:
1. Anything we get from environment to meet our needs and desires is called
____________________(resource)
2. When soil is washed away into streams, transported into rivers and finally lost to
the sea is defined as ________________________( soil erosion)
-
7/30/2019 2 - Environmental Resources
7/10
MULTIPLE CHOICES:
1. An extended period of deficient rainfall relative to the statistical multiyear average
for the reason is called
a. Drought
b. Flood
c. Deforestation
d. Soil erosion
2. Forest degradation is due to
a. Timber extraction
b. Construction of dams
c. Overgrazing
d. All the above
Additional information
ADVERSEEFFECTSOFDEFORESTATION:
Erosion of Soil: When forest areas are cleared, it results in
exposing the soil to the sun, making it very dry and
eventually, infertile, due to volatile nutrients such as nitrogen
being lost. In addition, when there is rainfall, it washes away
the rest of the nutrients, which flow with the rainwater into
waterways. Because of this, merely replanting trees may not
help in solving the problems caused by deforestation, for by the time the trees
mature, the soil will be totally devoid of essential nutrients. Ultimately, cultivation
in this land will also become impossible, resulting in the land becoming useless.
Large tracts of land will be rendered permanently impoverished due to soil
erosion
-
7/30/2019 2 - Environmental Resources
8/10
Disruption of the Water Cycle: Trees contribute in a large way in maintaining
the water cycle. They draw up water via their root, which is then released into the
atmosphere. A large part of the water that circulates in the ecosystem of
rainforests, for instance, remains inside the plants. When these trees are cut
down it results in the climate getting drier in that area.
Loss of Biodiversity: The unique biodiversity of various geographical areas is
being lost on a scale that is quite unprecedented. Even though tropical
rainforests make up just 6 percent of the surface area of the Earth, about 80-90
percent of the entire species of the world exist here. Due to massive
deforestation, about 50 to 100 species of animals are being lost each day. The
outcome of which is the extinction of animals and plants on a massive scale
Flooding and Drought: One of the vital functions of forests is to absorb and
store great amounts of water quickly when there are heavy rains. When forests
are cut down, this regulation of the flow of water is disrupted, which leads to
alternating periods of flood and then drought in the affected area.
Flood Drought
Climate Change: It is well known that global warming is being caused largely
due to emissions of greenhouse gases like carbon dioxide into the atmosphere.
-
7/30/2019 2 - Environmental Resources
9/10
However, what is not known quite as well is that deforestation has a direction
association with carbon dioxide emissions into the atmosphere. Trees act as a
major storage depot for carbon, since they absorb carbon dioxide from the
atmosphere, which is then used to produce carbohydrates, fats, and proteins that
make up trees. When deforestation occurs, many of the trees are burnt or they
are allowed to rot, which results in releasing the carbon that is stored in them as
carbon dioxide. This, in turn, leads to greater concentrations of carbon dioxide in
the atmosphere.
FORESTDEGRADATIONIN INDIA:
India is the second most populous and
seventh largest country in the world having
population over 1 billion with only 1.8% of the
worlds forest cover. The degradation of
forests in India is due to the construction of
dams, fuel, fodder, valley projects, industrial
uses, road construction, urbanization,
industrialization etc. Destruction of biotic potential of land leads to desertification. Such
problems arise due to overgrazing, indiscriminate felling of trees and over exploitation of
land resources. The effects of deforestation in India include soil, water and wind
erosion. Deforestation has a major impact on the productivity of croplands in two ways:
a) soil erosion leads to floods and drought b) increased dependency on cow dung and
crop wastes due to shortage of firewood affects crop productivity due to loss in soil
fertility.
SOLUTIONSFORDEFORESTATION:
The safe keeping of our precious planet lies with each and every member of its
human population. We are the ones accountable for our actions even though it is
ourselves we are accountable too. We have the power and knowledge to turn this
planet to a green and pleasant place to live or to completely destroy all life.
Deforestation is one of the major pressing environmental issues we face and one we
must address the solutions to and quickly if we are to restore the damage we have done
-
7/30/2019 2 - Environmental Resources
10/10
to the environment. Although forests may seem a small and insignificant part of the
world landscape. When seen as a whole they play a vital role in maintaining the
atmosphereand there is a real possibility that we could be left with nothing but waste
land if they were to disappear. So plant the trees, avoid the cutting of trees.
The limits of reserve strategy aimed to preserve the soil and prevent erosion
once the land was cleared did not really address the issue of deforestation.
Instead of protection to the soil it should have concentrated on protecting the
forest itself.
Planting different types of trees.
Overgrazing of animals should be prevented.
Forests play crucial role in regulation of global climate and temperature as the
forest cover absorbs the solar energy for primary production of food and energy.
Forests also regulate the flow of water from mountain highlands to croplands and urban
areas, and reduce the amount of sediment washing into streams, lakes, and reservoirs
by restricting soil erosion as the forests enrich soil binding capacity. Forests are fast
vanishing due to urbanization, industrialization and population growth. Deforestation
and over-grazing have been causing tremendous land erosion and landslides. Overgrazing is causing damage to the regenerating seedlings. More and more dams
construction and mining operations is leading to the displacement of tribal people.