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TNPSC Geography Free Notes – Natural vegetation &Soils and Agricultural pattern of India

இந்தக் கட்டுரையில், TNPSC குரூப் 1, குரூப் 2, குரூப் 2A, குரூப் 4 மாநிலப் போட்டித் தேர்வுகளான TNUSRB, TRB, TET, TNEB போன்றவற்றுக்கான  முறைகள் இலவசக் குறிப்புகளைப் பெறுவீர்கள்.தேர்வுக்கு தயாராவோர் இங்குள்ள பாடக்குறிப்புகளை படித்து பயன்பெற வாழ்த்துகிறோம்.

Natural vegetation &Soils and Agricultural pattern of India

Natural Vegetation

Green Cover in India
 Total Forest & Tree cover – 8,02,088 sq. k.m – (24.39%)
 Total Forest cover – 7,08,273 sq.km
 Tree cover – 93,815 sq km
Types of forests in India are
 Tropical Evergreen Forest
 Tropical Deciduous Forest
 Tropical Dry Forest

 Tropical Thorn Forests
 Mountain or Montane Forest
Tropical Evergreen Forest
 Annual Rainfall is 200 cm or more
 Annual average Temperature is 22˚C more
 Humidity exceeds 70%
 Growing Trees are Rubber, Ebony, Rosewood, Coconut, Bamboo, Cinchona, Cedar
Tropical Deciduous Forest
 Annual Rainfall – 100 to 200cm
 Annual average Temperature – 27˚C
 Humidity – 60 to 70 %
 Monsoon Forests
 Growing trees are Teak, Sal
Tropical Dry Forest
 Annual Rainfall – 50 to 100 cm
 Growing trees are Mahua, Banyan, Amaltas, Palas, Haldu, Bamboo, Babool
Semi-desert Vegetation
 Tropical Thorn Forests
 Annual Rainfall is less than 50 cm
 Low Humidity & High Temperature
 Growing Trees – Babool, Kikar, wild palms

Mountain Forest
Eastern Himalayan forest
 Annual Rainfall more than 200 cm
 Height – 1200-2400 m
 Growing trees are Sal, Oak, Laurel, Amura, Chestnut
 Oak, birch, silver, fir, fine, spruce and juniper are the major trees found at the altitude of
2400 to 3600m
Western Himalayan Forest

 Upto 900 m – semi desert vegetation
 900 – 1800 m – chir tree
 1800 – 3000 m – semi temperate coniferous forests
Alpine Forest
 It occurs all along the Himalayas with above 2400 m altitude. These are purely having
coniferous trees.
 The Eastern parts of the Himalayas have a large extent of these forests.
 Growing trees are Oak, Silver, Fir, Pine, Juniper
Tidal Forest
 Delta or Swamp forests
 Deltas, Estuaries and Creeks prone
 Delta of the Ganga-Brahmaputra
Coastal Forest
 Growing trees are Casurina, Palm and Coconut
 The coasts of Kerala and Goa
Riverine Forest
 Khadar Areas
 Growing trees are Tamarisk & Tamarind Trees
India has a rich and diversified wildlife. The Indian fauna consists of about 81,251 species of
animals out of the world’s total of about 1.5 million species.
Species 81,251
Invertebrates 6500
Molluscs 5000
Fishes 2546
Birds 1228
Mammals 458
Reptiles 446
Amphibians 204
Panthers 4
Insects 60,000

The Indian Board for Wildlife (IBWL)
 It was constituted in 1952 to suggest means of protection, conservation and
management of wildlife to the government.
 The Government of India enacted Wildlife (Protection) Act in 1972 with the objective of
effectively protecting the wild life of the country and to control poaching, smuggling and
illegal trade in wildlife and its diversities.
 To preserve the country’s rich and diverse wildlife a network of 102 National Parks and
about 515 Wildlife Sanctuaries across the country have been created.
Biosphere Reserves in India
 Biosphere reserves are protected areas of land coastal environments
 The Indian government has established 18 Biosphere Reserves
 In India Project Tiger was launched in April 1973 with the aim to conserve tiger
population in specifically constituted “Tiger Reserves” in India.
 Eleven of the eighteen biosphere reserves (Gulf of Mannar, Nandadevi, the Nilgiris,
Nokrek, Pachmarhi, Simlipal, Sundarbans Agasthiyamalai, Great Nicobar, Kanjanjunga
and Amarkantak) of India fall under the list of Man and Biosphere programme of
S.No. Biosphere reserves state
1 Achanakmar-Amarkantak Madhya Pradesh, Chattisgarh
2 Agasthyamalai Kerala
3 Dibru Saikhowa Assam
4 Dihang Dibang Arunachal Pradesh
5 Great Nicobar Andaman and Nicobar Islands
6 Gulf of Mannar Tamil nadu
7 Kachch Gujarat
8 Kanchenjunga Sikkim
9 Manas Assam
10 Nanda Devi Uttarakhand
11 The Nilgiris Tamil nadu
12 Nokrek Meghalaya
13 Pachmarhi Madhya Pradesh
14 Simlipal Odisha
15 Sundarbans West Bengal
16 Cold desert Himachal Pradesh
17 Sesahachalam hills Andhra Pradesh

18 Panna Madhya Pradesh

Soil is the uppermost layer of the land Surface

Types of Soils
The Indian Council of Agriculture Research (ICAR) set up in 1929 divides the Soils of India into
the following eight major Groups.
They are,
 Alluvial soil
 Black soils
 Red soils
 Laterite soils
 Forest and mountain soils

 Arid and desert soils
 Saline and alkaline soils
 Peaty and marshy soils
Alluvial soil
 Khadar – light coloured, more siliceous.
 Bhangar – the older alluvium composed of lime nodules and has clayey composition. It is
dark in colour.
 Formation – sediments deposited by streams and rivers when they slowly loose
 Chemical properties – rich in potash, phosphoric acid, lime and carbon compounds but
poor in nitrogen
 Nature –Sandy-loam-silt-clay profile shows no marked differentiation
 Distribution Ganga and Brahmaputra river valleys
 Crops growing Rice, Wheat, Sugarcane and Oilseeds
Black soils
 Formation – Derived from basalts of Deccan trap.
 Colour – black colour, due to presence of titanium, iron.
 Nature – Sticky when wet with high degree of moisture retentivity
 Crops growing Cotton, Millets, Tobacco and Sugarcane
Red soils
 Formation – decomposition of ancient crystalline rocks like granites and gneisses and
from rock type
 Chemical properties – rich in minerals such as iron and magnesium. Deficient in
nitrogen, humus, phosphoric acid and lime.
 Crops growing Wheat, Rice, Cotton, Sugarcane and Pulses
Laterite soils
 Formation – formed in the regions where alternate wet and hot dry conditions prevail.
It is formed by the process of leaching
 Chemical properties – Composed mainly of hydrated oxides of iron and aluminium,
 Nature – More acidic on higher areas poor in high level, cannot retain moisture
 Crops growing Coffee, Rubber, Cashewnut and Tapioca
Soil types

Forest and Mountain Soils
Differ from region to region depending on Climate.
 Formation – due to mechanical weathering caused by snow, rain, temperature variation
 Chemical properties –Deficient in potash, Phosphorus and lime.
 Nature – light, sandy, thin and found with the pieces of rock.
 Crops grown: Coffee, Tea, Rice, Maize, potato, Barley, Tropical Fruits and various types
of Spices.
Desert soils
 Formation – Due to prevalence of the dry Climate, high temperature and accelerated
evaporation, the soil is dry, it also lacks humus content due to the absence of vegetative
 Chemical properties –High Percentages of soluble salts, alkaline with varying degree of
calcium carbonate and are poor in organic matter; rich enough in Phosphate though
poor in nitrogen
 Nature – light in colour, low humus, friable structure, low in moisture
 Crops grown – Millets Barley, Cotton, Maize and Pulses (with irrigation)
Saline and Alkaline Soils

 Formation – formed due to ill drainage which Causes water logging, injurious salts are
transferred from subsurface to the top soil by the capillary action, it causes the
salinisation of soils
 Chemical properties – Liberate Sodium, Magnesium and calcium salts and sulphurous
 Nature – It consists of an excess of sodium salts and mineral fragments which are
Peaty and Marshy Soils
Formation – formed in humid regions from the Organic matter.
Chemical properties – Deficient in potash and Phosphate.
Nature – Contain considerable amount of Soluble salts and 10-40 per cent of organic
matter and high proportion of vegetable matter.
 The agriculture in India employs more than 50 percent of the population of the country
and accounts for about 25 percent of the national income.
 Agriculture in India is determined by a set of factors. Some of the important factors:
1. Physical factors: relief, climate and soil.
2. Institutional factors: Size of farm holdings, land tenure, and land reforms.
3. Infrastructural factors: Irrigation, power, transport, credit, market, insurance and
storage facilities.
4. Technological factors: High yielding varieties of seeds, chemical fertilisers,
insecticides and machinery.

Types of Farming
a) Subsistence Farming
Preference is given to food crops. In addition to the food crops, sugarcane, oilseeds, cotton,
jute and tobacco are also cultivated. Traditional farming method results in low productivity.
b) Shifting Agriculture
 Once the land is cleared, crops are grown for two to three years.
 It is also called as “Slash and burn” cultivation.
Different names of shifting agriculture in different regions in India

Name Place
Jhum Assam
Poonam Kerala
Podu Andhra Pradesh, Odisha
Beewar, Mashan, Penda, Beera Various Parts of Madhya Pradesh
c) Intensive Farming
Aims to Maximise yields from available land, through various means such as heavy use of
pesticides and chemical fertilizers.
d) Dry Farming
Most of the areas under dry cultivation entertain only one crop per year
e) Mixed Farming Agriculture
Mixed farming is defined as a system of farm which includes crop production, raising livestock,
poultry, fisheries, bee keeping etc. .
f) Terrace Cultivation
This type of cultivation is practiced specially in hilly areas
Cropping Seasons in India

Northern States- Major crops

Southern States- Major crops

Kharif Season

Rice, Cotton, Bajra,
Maize, Jowar, Tur

Rice, Ragi, Maize,
Jowar, Groundnut

Rabi Season

Wheat, Gram, Rapeseeds,
Mustard, Barley

Rice, Maize, Ragi,
Groundnut, Jowar

Zaid Season

Vegetables, Fruits,

Rice, Vegetables,

 Watering of agricultural plants through artificial means is called irrigation.
 Being a hot country with seasonal and irregular rainfall, it always needs irrigation to
carry out agricultural activities during dry period.
Sources of Irrigation

 Canal irrigation
 Well irrigation
 Tank irrigation
Canal Irrigation
 It is the second most important source of irrigation in our country.
 Percentage of area under canal irrigation in our country is 24%.
 The canals are of two types:
 Inundation Canals: In this, water is taken out directly from the rivers without making
any kind of barrage or dam
 Perennial Canals: These are developed from perennial rivers by constructing barrage
to regulate the flow of water.
 About 60 percent of the canal irrigated area falls in the northern plains of India.
Well Irrigation:
 A well is a hole or trough, usually vertical, excavated in the earth for bringing Ground
water to the surface.
 Wells are of two types:
 Open wells: This type of irrigation is widely practiced in the areas where
groundwater is sufficiently available.
 Tube Wells: Tube wells are developed in the areas of low water table, sufficient
power supply and soft subsurface geological units.
 Well irrigation is the most important source of irrigation as it contributes about 62
percent of net irrigated area in India.
 The top of percentage of areas under well irrigation -Uttar Pradesh.
Tank Irrigation:
 Irrigation by tanks is a very old system in India.
 The tank irrigation is popular in the peninsular India due to the following reasons:
 The undulating relief and hard rocks make difficult to dig canals and wells.
 Natural depressions serve as reservoirs.
 Top state of tank Irrigation-Tamil Nadu
Modern irrigation methods:
Drip System: This is introduced by Israel country.70% of water can be saved by this
irrigation system
Rain Gun: used to serve for crops which used to grow up to 4 feet or high also typical
usage of Rain guns are in sugarcane, maize crop.

Central-pivot irrigation: It is also called waterwheel and circle irrigation. It is a method
of crop irrigation in which equipment rotates around a pivot and crops are watered with
 2015-Prime Minister Krishi Sinchayee Yojana: Improve On-farm water use efficiency to

reduce wastage of water.


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