ONLINE ASSIGNMENT 2014
TOPIC: NATURAL RESOURCES
SUBMITED ON:23/6/2014
SUBMITED TO,
SUBMITED BY,
Mrs.Radha
Saranya Viswan
Natural science Natural
science
R.NO:125
INDEX
Introduction
Resources are the “source of supply or
support,generally held in reserve”. They include useful information ,materials
or services.Resourses are of two type ,human resources and natural resources
.Human resources include the wisdom,knowledge, experience labour etc. of
mankind.Natural resources are the naturally occurring substances of the
biosphere ,which can support and sustain life.They include the goods and
services provided by natural environment.
The survival and success of
mankind depends upon the availability,conservation,recycling and replenishment
of natural resources.solar energy,pond forest, wind,soil etc. are vital natural
resourses.The disturbances lead the destruction of eco system .
CONTENT DEVELOPMENT
Natural resources are the naturally
occurring resources.That is very beneficial for our life.The survival and
success of mankind depends upon the availability ,conservation and recycling
.Many of the resources are only limited in stock so that they may run down due
to constant use.To make the situation worse,modern civilization demands the
over exploitation and overwastege of natural resources.This leads irreversible
qualitative degradation of natural environment
ABIOTIC AND BIOTIC
Based on origin ,natural resources are classified into abiotic and
biotic resources .Abiotic resources include the non living matter,not obtained
from or produced by living organism .Land,water,air,minerals etc. are
examples.Biotic resources include living organisms and their products.
Based on utility ,natural resources are classified into food
resources ,raw material resources and
energy resources
Principal natural resources
Natural resources ,
important to human welfare, include energy resources, mineral resources, food
resources, forest resources, land resources, water resources, edaphic ( soil)
resources etc.
Forest resources and their conservation
Forests are large treasure houses of a
huge wealth of natural resources. They significantly contain nearly 50% of the
terrestrial species of plants and animals. Right from his emergence on earth
man has been using forests as his habitat and also as a source of food and
other basic requirements. Initially , he lived in the forests as a hunter and a
food gatherer, utilizing all the available natural resources. But later on, he
turned to be the main destroyer of forests.
Importance of Forests
Forests are valuable to
us in many ways. They satisfy our needs for timber and other wood products,
favorably influence the climate atmosphere and water resources and protect the
soil from wind erosion. The tranquility and the scenic beauty of the wilderness
always arouse our aesthetic imaginations and fine sentiments. Forests are also
useful for recreational purposes, such as observations of wild life and
camping, for meeting our cultural requirements.
Economic or commercial values of forests
(1)
Provide fuel wood for domestic and industrial uses, and timber for
buildings, furniture, boats, railway sleepers and several other purposes
(2)
Supply raw materials for wood pulp in the manufacture of paper, rayon,
motion picture films, plywood, cardboards, etc.
(3)
Provide food items in the form of roots, tubers, leaves, fruits, berries,
nuts, spices etc.
(4)
Medicines like quinine and camphor, and products like turpentine,
resins, rosin, oils, dyes, gum, charcoal etc. are obtained from forest trees
(5)
Serve as a source of sustainable income through ecotourism
Ecological values
Apart from
the aesthetic, recreational and economical values, forests have very grate
ecological values too. The major ecological roles of forests are the following
(1) Control atmospheres qualities such as
humidity, temperature, gas composition and air circulation.
(2) Moderation of climate through transpiration: Forest
can make the climate less extreme. Continuous transpiration of plants increase
atmospheric water contents and humidity, decrease atmospheric temperature and
makes the atmosphere cool. A cool atmosphere always promotes rain falls
(3) Oxygenation of atmospheric air through photosynthesis:
The rich flora of forests plays a vital role in increasing the oxygen level and
decreasing the carbon dioxide level of atmospheric air.
(4) Increase soil fertility by promoting humus
formation and nitrification: Forests increase soil fertility in two ways. In
the first case, the decay of fallen leaves and other parts promotes humus
formation and their by increase soil fertility. In the second case forests
promote rain falls. Large amounts of atmospheric oxides of Nitrogen dissolves
in the rain water and get deposited on the soil surface. This nitrogen gets
incorporated with other elements and forms nitrogenous compounds. This
tremendously increases soil fertility.
(5) Control soil erosion and flash flood and
protect top soil and water resources : Forests make the atmosphere cool and
promote humus formation. These two factors makes the top soil moist and spongy
.This ,in turn increases it water holding power, that is the powers for absorbing
and retaining water . The porous soil under a forest cover can easily absorb
rain water or melting snow. This reduces flash flood and soil erosion
(6) Forests conserve water and regulate
water cycle.
(7) Forests regulate the flow of rivers,
prevent their silting and pollution, control their flooding and thus make them
highly serviceable.
(8) Forests provide an extensive natural
habitat for a verity of flora and fauna. These are regularly interacting, and
this interaction maintains the stability of ecosystem and balance of nature.
Distruction
of forests
In the early historic times ,
the extent of the lush and green-clad forest cover was far greater .Over
thousands of years, much of the original forest cover disappeared mainly due to
constant use and overexploitation by man . Large-scale clear –felling and
timber extraction , over grazing, extension of agriculture and commercial crop
plantations, construction of roads , railways , dams and hydro-electric
projects, mining , quarrying, urbanization, industrialization, etc. are some of
the major causes for extensive deforestation. Natural factors, such as flood,
soil erosion wild fire, earth-quake, land-slide, etc. have also contributed to
the destruction of forests. The common causes of deforestation can be
summarised as follows.
(1) Shifting cultivation which involves the
‘slash and burn’ agricultural practice of tribals and landless people who clear
trees for growing subsistence crops
(2) Overgrazing by domestic animals, and the conversion of forests to pastures for
them.
(3) Extensive collection of firewood.
(4) Commercial logging and clear- filling.
(5) Urbanization, industrialization, mining,
quarrying, construction of dams and hydel projects, etc.
(6) Government-sponsored programmes for the re-settlement
of the people who have lost their lands.
(7) Natural calamities, such as volcanic
eruption earthquakes, massive landslides, wildfires, floods, acid rains, etc.
General effects of deforestation
Large-scale destruction of forests
will lead to a very serious situation, dangerous to the normal existence of man
himself .Some of the adverse effects of deforestation are the following.
(1) Reduces the food and space of wild
animals : Senseless deforestation has caused a drastic reduction in the living
space and food of wild animals. This has lead to the local extermination of
several species.
(2) Increase the co2 and
decrease the o2 levels of atmospheric air : Destruction of forests
increase the concentration of co2 and decrease the concentration of
o2 in the atmospheric air.
(3) Decreases humidity, makes the
atmosphere hot, reduces rain fall, adversely affects surface water and ground
water resources, and causes desertification
(4) Increase the severity of soil erosion
and flood: In the absence of trees, atmosphere becomes hot, and humus formation
becomes inadequate.
(5) Reduces soil fertility :
deforestation can considerably reduce soil fertility this happens in three ways
(a)By reducing humus formation
(b) By
reducing rain fall and the deposition of the oxides of nitrogen in the soil
through rain water
(c) By
causing the washing away of the fertile topsoil by run of waters
(6)Genetic erosion, loss of
biodiversity and disturbances in ecological balance
(7) Effects of deforestation on
tribal populations: The tribal people, or the ethinic races, of India are traditionally forest
-dwellers and most of them are still
confined to forest, extensive deforestation causes the shrinkage of their
habitat, displaces them from settled areas, severely hits their
livelihood and causes untold miseries and sufferings to them.
Conservation of forests
Conservation of forests involves the
following important measures
(1) avoid clear- felling and always compensate
tree-felling by tree –planting
(2) protection of forests from wild fire,
flood, and soil erosion
(3) protection from diseases , parasites
and pests by chemical and biological methods
(4) ban on over-grazing
(5) maintenance of forests by
afforestation and reforestation
(6) implementation of social forestry,
urban forestry and agrp-forestry programs by planting and protecting trees.
(2)Water resources
Water is an indispensable requirement for life on earth and
is the only planet known to contain liquid water in substantial quantities.
Water is directly involved in all the life processes of organisms and no
organism can exist on earth without water. It is generally held that life could
not have probably emerged on earth, if water was not present on the primaeval
earth during the pre-biotic periods.
Importance of water
Water is the” elixir of life”,
indispensable for all life activities .In fact, it is a part of life itself,
since it serves as the medium in which all life processes occur. Within the
body of a living organism , water serves as an excellent solvent for the
dissolution of all kinds of molecules, forms an ideal medium for enzymatic
reactions, functions as a powerful ionizing agent acts as a temperature
regulator, actively participate in biochemical reactions, and plays a major
role in transport of substances.
Fresh water resources
There are two major fresh water
resources, namely surface water and ground water, the former includes running
and standing fresh water bodies and the later constitutes 9.8% of the freshwater
bodies. The running or lotic freshwater bodies includes brooks, springs,
rivers, etc. the stagnant or the lentic fresh water bodies include natural and
artificial reservoirs, lakes, ponds, etc.
Ponds
Ponds
are the smallest water bodies found on earth. It should be considered as an eco
system, this is because many organisms like plants, fishes, reptiles,
amphibians, and microorganisms are also live here. Pond helps in the
maintenance of underground water level. In past days there were at least two
ponds in each house. Both have different purposes. One was used for drinking
purposes and other for domestic purposes. The numbers of ponds are decreasing
day by day due to the filling-up of ponds for construction works. This
inversely affects the level of underground water.
River
Rivers are the boon of God. Kerala, one of the smallest state
in India is blessed with comparatively big 44 rivers. They were rich with
abundant water potential in past days, but the situation is diminishing very
fastly. The increasing rate of water pollution, river mining, and construction
of dams adversely affect the natural flow and purity of river. It causes
scarcity of water. River flood-plains are natural ‘safety valves ‘to control
flood. The wet lands in them are
nature’s flood control systems into which the over flowing rivers can spill
large bulks of water. 
Sea
The 97% of water is present in the earth is on the oceans. Sea
provides earnings for many families in Kerala those who are fishermen. It is
the biggest eco system in the world. There are many aquatic plants in sea. They
produce huge amount of oxygen for earth. Verities of plants and organisms exist
in this ecosystem. Some of them are known and others are unknown to human
beings. It has great economic importance.
Today this ecosystem is getting disturbed through the involvement of
human beings. All rivers are merging
with sea by bearing a lot of wastes. It leads to the extinction of many marine organisms.
Sustainable water management
It
is high time that the people all over the world are made aware of the grave
situation of acute water scarcity
through’ save water ‘campaigns and effective measures are taken for sustainable
management of world’s water resources. Some of the measures suggested for this
purpose are the following
·
Construction of as many small reservoirs as
possible, instead of mega projects for trapping and storing the run- off water.
· Construction
of small catchment dams and protection of wetlands.
· Construction
of bunds across hill tops.
· Soil
management, catchment development and afforestation to augment the recharging
of underground aquifers.
· Prevention
of leakage from dams, canals and pipe lines.
· Widespread
rain water harvesting
· Drip
irrigation in agriculture to reduce water use.
· Judicious
utilization of water, avoiding wastage.
·
Total avoidance of freshwater pollution
Conclusion
The
survival and success of mankind depends upon the availability, conservation,
recycling and replenishment of natural resources. Solar energy, soil, air,
wind, water, mineral deposits, fossil fuels and living organisms are vital
natural resources’. Many of these resources’ are only limited in stock so that
they may run down due to constant use. To make the situation worse modern
civilization demands the overexploitation and over wastage of natural resources’
this may cause irreversible qualitative degradation of natural environments
Reference
Environmental
studies, phytogeography- A.R.Ajith Kumar Ramesh, K.K Bhaskran
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