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INTRODUCTION
Natural resources are useful raw materials that we get from the Earth.
Which can support and sustain life in other words, they are nature
resources which support life on earth. They occur naturally, which
means that humans cannot make natural resources. They include the
goods and services provided by natural environment. Solar energy,
soil, air, wind, water, mineral deposits fossil fuels and living organisms
are virtual natural resources. Many of these resources are only limited
in stock so that they may run down due to constant use. Modern
civilization demands the overexploitation and over wastage of natural
resources. This may cause irreversible qualitative degradation of
natural environments. There are several ways to classify natural
resources, including where they come from and if they are renewable
or not. If natural resources come from living things or organic materials,
then they are considered Biotic resources. Biotic resources include
plants, animals, and fossil fuels. Abotic resources originate from
nonliving and inorganic materials. For example, air, sunlight, and water
are abiotic natural resources. Minerals (gold, copper, iron, and
diamonds) are also considered abiotic.
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I. FORESTS
Forests are large treasure houses of a huge
wealth of natural resources. A forest is a complex ecosystem which is
predominantly composed of trees, shrubs and is usually a closed
canopy. Forests are storehouses of a large variety of life forms such as
plants, mammals, birds, insects and reptiles etc. 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.
Forests are valuable to us in many ways. They satisfy our needs
for timber and other wood products, favourable influence the climate,
atmosphere and water resources and protect the soil from wind
erosion.Tranquility and the scenic beauty of the wilderness always
arouse our aesthetic imaginations and fine sentiments.
ECONOMIC AND ECOLOGICAL VALUES OF FORESTS
Provide food items in the form of roots, tubers, leaves, fruits berries,
nuts, spices, etc.
Serve as a source of sustainable income through ecotourism.
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Medicines like quinine and camphor and products like turpentine,
resins, oils, gum, charcoal etc are obtained from forest true.
Control atmospheres qualities, such as humidity, temperature gas
composition and air circulation.
Increase soil fertility by promoting humus formation and
nitrification.
Forests conserve water and regulate water cycle
Control soil erosion and flash flood and protect top soil and water
resources.
CONSERVATION OF FORESTS
Conservation of forests involve the following important measures
I. Avoid clear felling and always compensate tree felling by tree
planting.
II. Protection of forests from wild fire, flood and soil erosion.
III. Ban on over grazing.
IV. Maintenance of forests by afforestation and re-forestation.
V. Protection from diseases, parasites and pests by chemical and
biological methods.
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II. MANGROVES
Mangroves are salt tolerant trees or shrubs, growing
between mean sea-level and the high tide mark of tropical and
sub-tropical coastlines and also along the banks of estuaries and
salt marshes. They form distinct intertidal communities and also
serve as an interface zone between land and sea. Mangrove
ecosystems also called mangrove forests or mangals are thickly
vegetated saline brackish water swamp forests seen mostly
bringing the tropical and subtropical coastlines.
MANGROVE FORESTS OF INDIA
In India, mangroves are more extensive in the rivers deltas,
associated with the Bay of Bengal. The largest mangrove forest in
the world is the Sundarbans in the Ganga-Brahmaputra delta
Thick mangrove forests are also found in Andaman and Nicobar
Islands. In Kerala mangrove forests are very rare. Thin scattered
and fragmented mangrove track are found in Kollam,
Thiruvanthapuram, Alappuzha, Ernakulam, Thrissur, Kozhikode,
Kannur, etc.
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FEATURES OF MANGROVE PLANTS
Mangrove plants in general, are characterized by the presence
of needle-shaped and negatively geotropic roots called
pneumatophores, Stilt-roots and prop roots for fixation and anchorage
viviparous for successful dispersal. The internal structure of mangrove-
plants is somewhat similar to that of desert plants. The stem is mostly
bushy and done shaped due to cymosely branching. Leaves in most
cases are small, thick entire, succulent and often glossy.
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ECONOMIC IMPORTANCE OF MANGROVES.
In many countries mangroves provide a wide range of
products and services to mankind. Some of their economic roles are,
I. Provide green manure for agricultural purpose
II. Provide honey and wax in large quantities
III. Provide high quality fuel wood to the rural folk of the coastal areas
of tropical countries.
IV. The complex root structure of mangroves helps the accumulation of
organic and inorganic materials.
V. Mangroves are important land builders which play a vital role to
form land and to extend shores.
VI. The shallow waters around mangroves provide highly suitable
feeding and breeding places for many estuarine fishes.
VII. The leaf detritus from mangroves supports prolific fish populations
and other organisms.
VIII. Mangrove ecosystems filter surface water runoff .This prevents the
large scale loss of nutrients to sea.
IX. Mangroves support a large number of resident and migratory birds,
providing them enough food, feeding grounds and nesting sites
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III. WETLAND
A patch of land that develops pools of water after a rain storm
would not be considered a wetland even though the land is wet.
Wetlands have unique characteristics, they are generally distinguished
from other water bodies or land forms based on their water level and
on the types of plants that live within them.
Wetlands are a home to many species of migratory and resident birds,
reptiles and amphibians, fish, insects, and plants. They also benefit
society by storing floodwaters, filtering pollutants, serving as a carbon
sink, and providing recreation sites for boating and fishing.
Wetland systems naturally produce an array of vegetation and
other ecological products than can harvested for personal and
commercial use. The most significant of these is fish which have all or
part of their life-cycle occurs within a wetland system.
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HUMAN IMPACT
Overfishing is the major problem for sustainable use of wetlands.
The field of aquaculture within the fisheries industries is eliminating
mass areas of wetland systems through practices seen such as in the
shrimp farming industry’s destruction of mangroves.
CONSERVATION OF WETLAND
Wetland has historically been the victim of large draining efforts
for real stake development or flooding for use as recreational lakes.
Wetlands provide a valuable food control function and very effective at
filtering and cleaning water pollution. To replace this wetland
ecosystem services enormous amounts of money hand to be sprint for
controlling floods.
IV. SACREDGROVE
Sacred Groves, one form of nature worship, are considered as
“Sacred Natural Sites” A sacred grove or sacred woods are many
grove of frees of special religions importance to a particular culture
sacred groves were most prominent in the ancient near east and pre
historic Europe. In India sacred groves are scattered all over the
country. These sacred deities are associated with local Hindu Gods,
sacred groves of Islamic and Buddhist origins are also known sacred
groves occur in a variety of places-from scrub forest in the Tar Desert
of Rajasthan. . A diverse range of ecosystem is preserved in grove
tradition along with its regional and local identities as represented in
name, practices and management of groves.
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Sacred groves have been reported from all over India which acts as
reservoirs of rare fauna and flora: groves include urbanization over
exploitation of resources and environmental destruction from Hindu
religions practices. While many of the groves are looked upon as abode
of Hindu Gods in the resent past a number of them have been partially
cleared for construction of shrines and temples. Sacred groves are
being destroyed as a part of urbanization.
ECOLOGICAL FUNCTIONS AND SERVICES
Water conservation is perhaps the most well documented
ecological service provided by the sacred groves.
Highland groves (Western Ghats and Himalayan region) are
important for their soil and water conservation activities which
are beneficial for the local inhabitants in terms of less soil erosion,
preventing flash flood, supply of water in lean season etc.
The other services are temperature control, fire resistance, plant-
animal interaction.
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CONCLUSION
Forest, wetland, mangroves, sacred groves are the important
natural resources and it provides some important roles in life one of
them provides an extensive natural habitat for a variety of organisms.
These are regularly interacting and this interaction maintains the
stability of ecosystems and the balance of nature from the study
students will able to understand the importance of Natural resources
for better science teaching and learning.
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REFERENCE
1. Bscs, “Biology Teachers handbook” Second edition 1971.
2. Siddiai and siddigil “ Teaching of science” Doaba house Delhi-2006
P.C.Joshi & Namitha Joshi, A Text Book Of Environmental Science,
Balagi Offset Delhi,2009
Checked and Corrected By
RESHMA THULASI T L
Assistant Professor in Natural Science
F.M.T.C, Mylapore, Kollam
