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NATURAL RESOURCES
NATURAL RESOURCES
By G.SwethaVIII -‘A’
LAND RESOURCESLand is the most fundamental resource
required to support life. But only a small percentage of the land surface is suitable for habitation. On the basis of the characteristics
and utilization of the land, the country determines its land use pattern. But land
distribution is quite uneven throughout the world.
AUSTRALIA CANADA FRANCE BRAZIL INDIA0
20
40
60
80
100
120
OTHER USEFORESTPASTURECROPLAND
MOUNTAINS MOUNTAINS COVER ONE-FIFTH OF THE
WORLD’S LANDSCAPE. MOUNTAINS BLOCK PATH OF RAIN-BEARING WINDS AND CAUSES
OROGRAPHIC RAINFALL. ROKY MOUNTAINS OF NORTH AMERICA,THE ANDES MOUNTAINS OF
SOUTH AMERICA, ATLAS MOUNTAINS OF AFRICA,THE GREAT HIMALAYAS OF ASIA,THE GREAT
DIVIDING RANGE OF AUSTRALIAARE SOME EXAMPLES OF MOUNTAINS.
PLATEAUS
Plateaus are large elevated tableland separated from its
surroundings areas by steep slopes. They have a fairly level land on the top. Plateaus are quite widespread and are found all over the earth.
Plateaus have been subjected to erosion over the years by agents of
gradation. plateaus are rich in mineral deposits so mining
activities are carried out in these regions. The Deccan plateau in India,
The plateau of Tibet in Asia, the Colorado plateau of north America, are some examples
of plateaus.
PLAINSPlains are broad and leveled stretches of land mostly found in low altitude regions
and is most suitable for agriculture. Rivers that carry fertile silt and water from the
mountains make it fertile.ganga-brahmaputra plains of india,nile plains of
Africa are some examples of plains.
SOIL RESOURCES
Soil is the uppermost layer of the earth. It originates from parent rock and
contains both organic and inorganic substances. Fertility of a soil depends
on depth.
SOIL PROFILE
* Soil profile refers to a vertical cross section of the soil from the surface to the parent rock. *The O-Horizon is the upper most layer of the soil. It is dark in color due to humus present in the soil. *The second layer is the A-Horizon or top soil. It experiences leaching and also contains humus which provides plants with nutrients. * The next layer is the B-Horizon. It contains minerals. It has lesser amount of humus * C-Horizon consists mostly of weathered parent rocks. *The last layer is the R-Horizon or the parent rock.
F
SOIL PROFILE
FORMATION OF SOIL The formation of the soil depends on the following factors:*Parent material *Relief*Climate*Time*Flora, Fauna and Microorganisms
PARENT MATERIAL: These are the from which the soil is formed due to weathering. These are of two types:
*Transported: This is formed by the river alluvium glacial deposits, wind blown deposits etc and has no relationships with the region of deposition is called transported soil. This Is also called ex-situ. Eg: Alluvial soil.*sedentary: This has a strong correlation with the parent rock and is not transported by the agents of gradation is called as sedentary soil.It is also known as in-situ e.g.: blackSoil.
RELIEF: Altitude and the slope of the
land determine the rate of accumulation of soil.
CLIMATE: soil formation mainly depends
on the climate of a region especially, its temperature and rainfall. Few centimeters of soil takes nearly a thousand years to form
DIFFERENT TYPES OF SOIL
ALLUVIAL SOIL BLACK SOIL RED SOIL LATEREITE SOIL ARID SOIL MOUNTAIN SOIL SALINE AND ALKALINE SOILS PEATY AND MARSHY SOILS
ALLUVIAL SOIL
Alluvial soil is formed by the alluvial deposits of various rivers. It consists of sand, silt and clay. This soil is light to dark in colour and is porous and rich in humus. There are two kinds of alluvial soil bhangar soils-older alluvial soil and khadar soils-newer alluvial soil. This soil is most fertile & suitable for the growth of rice and jute. Eg: Punjab, Uttar Pradesh, river ganga-brahmaputra.
BLACK SOIL This soil is formed due to weathering of basaltic lava rocks. It is black to grey in colour due to presence of iron oxide. Black soil is rich in clay content and can retain moisture. It is found Maharashtra, Andhra Pradesh etc. The soil suitable for cultivation of cotton. This black soil is known as black cotton soil and as regur soil.
RED SOIL
This soil is red in colour due to the presence of iron oxides. It is mostly available in low rainfall region. The red soil is sandy in nature. Red soil is rich in iron content and has very less humus. This soil is located in the periphery of the black soil region in the states of Tamilnadu, Madhya Pradesh, Maharashtra and West Bengal. Red soil is suitable for the growth of millets, potatoes, wheat, etc.
LATERITE SOIL
This soil is mostly available in high temperature and heavy rainfall regions. Laterite soil is infertile in nature as the soil nutrient due to soil are washed away or percolate downwards due to heavy rainfall. This process is also called leaching. The Laterite soil is good for the growth of tea,coffee,cashew rubber and coconut.This is found in the states of Assam, Tamilnadu etc.
ARID SOIL
This soil is red to brown in colour. It forms mostly in the dry regions, such as deserts. It has sandy texture and is saline in nature and also lacks in humus and moisture. Its fertility can be improved by use of irrigation. It is mostly found in Rajasthan, Punjab Haryana and Northern Gujarat.
MOUNTAIN SOIL Mountains are rich source of
minerals natural forests and rivers.It is found on the hill slopes and high altitude regions. It is generally thin in the mountanious region and is rich in humus content. The type of soil varies according to the altitude.Tea,coffee,spices and fruits are grown in these regions. These areas are found in the northern and northeast areas in india.these are predominant in the states Assam Sikkim etc.,
SALINE AND ALKALINE SOIL These soils are unfit for
cultivation as they contain various salts like sodium, calcium magnesium etc., in higher concentrations. They are sandy to loamy in texture. They are found in Gujarat, Haryana, Uttar Pradesh.
PEATY AND MARSHY SOILSThese soils are found in humid regions
they are formed by accumulation of organic matter and are generally black in colour.
Peaty and marshy soils are acidic in nature. These are mostly found in coastal areas of kerala,odissa,sunderbans regions of
the west bengal.
SOIL EROSIONIt is the removal of topmost layer of the soil. It occurs
due to natural factors and human activities. Various human activities deforestation river erosion etc.,It causes loss of fertility and decrease cultivity.Rivers cut through the soil and form deep channels called gullies sometimes layers of soil over a large area are moved by running water. This is known as sheet erosion. Land which becomes unfit for cultivation is known as bad lands. Soil eroded by the rivers causes heavy silting and may even divert or change the course of a river. This affects the water table, plants, animals and human beings alike.
*CONTOUR PLOUGHING:It is done to decelerate the flow
of water.*TERRACE CULTIVATION:
It is done by cutting steps on the slopes of hilly areas making terraces*STRIP CROPING:
It involves growing of strips of grass between crops.*Tress are planted to check the wind velocity also called as shelter belts.
SOIL CONSERVATION
WATER RESOURCES
Earth is a watery planet. It is the most important natural resources. Water is a renewable resource. Nearly 71% of the earth is covered with water and about 96.5% of the total volume of water. Water is used for various purposes.The availability of water varies with space and time. Wateravailability is mainly during the monsoon seasons. When the rainfall fails in monsoon season there will be scarcity of water. Many dams were built to use water storage of water. The water is also stored in reservoirs for various purpose.These dams are called multipurpose dams. Eg: damodar valley project on river damodar.
SCARCITY OF WATER
*Large growing population.*Growing demand of water.*Drying up of water sources.*Continuous lowering of water table.*Variation in seasonal and annual precipitation.*Due to social inequality.*Overuse of industrial effluent, chemical fertilizer, contaminate water.*Low awareness about water pollution.
CONSERVATION OF WATER
*Rain harvesting: Rain is the main form of
water for us. Rainwater harvesting system methods is most important natural methods. In the process rainwater is collected from the rooftops of houses and reservoirs where it is stored. It recharges the groundwater for drinking as well as for irrigation. Rooftop rainwater harvesting is widely practiced in Rajasthan.
OTHER WAYS TO CONSERVE WATER
*Sprinkle and drip irrigation reduce wastage of water and helps in conservation mainly in the dry areas.
*Afforestation is an important method to conserve water. It increases percolation and recharge the underground water table.
*mulching is a protective covering usually of organic matter such placed around the plant to prevent evaporation of moisture. This is another way to conserve water.
*Water pollution can be controlled by treating industrial effluents.