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iii) During the day, land gets hot faster than the sea.
At night, the land gets cool earlier than the sea. Therefore, temperature is
moderate in coastal areas, and the landlocked areas have extreme
temperature.

iv) Ocean currents are mainly of two types: Warm currents and
cool currents. Warm currents are responsible for the warm climate of the
coast as they pass from that region. Due to this phenomenon, the flow of
warm Gulf Stream along the North-East European coast does not freeze the
region even during winter.

v) Mountains are the barriers for the movement of winds. The
cold winds blowing in China are stopped from entering into India in winter by
the Himalayas. That’s why, Canton of China is much cooler than Kolkata in
winter.

ATMOSPHERIC PRESSURE AND WINDS

When the air above the atmosphere exerts pressure due to its weight on a
surface from all sides, it is called atmospheric pressure. Pressure and
temperature are inversely related to each other. The air pressure is low in areas
of high-temperature as hot air is always light and exerts less pressure. Wind is
the moving air. The winds naturally blow from an area of high-pressure to a low-
pressure area.

i) This area is near the equator and is the hottest
zone. The air becomes lighter and goes up. This belt is also known as the
doldrums or the region of calm conditions.

ii) Near 30°N and 30°S lies the Subtropical high-
pressure belt which is also known as the horse latitude. The wind here is very
light and variable. Generally the weather here is dry. Almost all the hot
deserts of the world are located here.

iii) The belt that lies around 60°N and 60°S, is the
Subpolar low-pressure belt. The presence of landmasses in the Northern
Hemisphere, keeps the land very cool. High pressure is there at many places.
Due to this, the stretch of the low-pressure belt breaks in the Northern
Hemisphere.

iv) This belt is located at the poles. Near the pole, the air is cold and
heavy and thus the temperature is low.

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PERMANENT WINDS

Permanent winds are the winds that blow all through the year and in a
definite direction. These winds blow from the high-pressure regions to the low
pressure regions. These winds move towards right in the Northern Hemisphere
and towards left in the Southern Hemisphere due to Coriolis force of the Earth
i.e. the rotation of the Earth.

i) The calm and variable winds of the equatorial belt are called
Doldrums. This belt is in between the trade winds of the Northern and
Southern Hemispheres and is thus called the Inter Tropical Convergence Zone
(ITCZ).

ii) The winds that blow in the belt between 5° and 30° north and
south are the Trade Winds which originate due to the pressure gradient of
the subtropical belts (high pressure area) to the equatorial belt (low pressure
area). They are known as the northeast trade winds in the Northern
Hemisphere, and are called the southeast trade winds in the Southern
Hemisphere.

iii) These winds blow in the area between 30° and 60°
latitudes of each hemisphere. They travel from the poles towards subtropical
high-pressure zone. They vary in both direction and intensity. Absence of the
landmasses in the Southern Hemisphere makes the westerlies very strong
and are called by various names like roaring forties, howling fifties and
screeching sixties.

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PRESSURE GRADIENT
The rate of change in atmospheric pressure in between
two regions is called the Pressure Gradient.
iv) These winds are present at the poles. They travel from a
polar high-pressure zone to a sub-polar low-pressure zone.

PERIODIC WINDS

These are the seasonal winds that are seen due to differential heating of land
and sea. Some of them are:
i) The word monsoon is originated from the Arabic word

'mausim' which means season. In every six months, these winds reverse their
direction. The Indian sub-continent is highly affected by these monsoon
winds. A low pressure is generated on the land because of the excessive
heating of land in summer. Because of this pressure gradient, the winds move
from a high pressure zone at Arabian Sea, Indian Ocean and Bay of Bengal,
towards low pressure areas in the interior of India. These are the winds, full
of moisture. This is the reason for rain in northern plains which is considered
to be very important for Indian agriculture. This is known as south-west
monsoon.
ii) During the day near the coasts, the land becomes
hotter compared to the sea. This results in low pressure on the land and
higher pressure on the sea. The Cool wind thus blows from the sea to the
land. This is known as sea breeze. During night, the opposite process
happens and the winds move from land to sea. This is due to the fact that
the land gets cooler earlier than the sea. This is known as land breeze.

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LOCAL WINDS

Winds that generate because of some local factors and the effect of which is
restricted to a small region are called local winds. Examples of some of them
are:

i) Winds produced due to the advection of hot air from a warm
source region, are hot local winds.

a) Foehn: On a mountain range, the warm dry winds are originated on the lee
side (rain shadow). These commonly occur in Alps in Switzerland.

b) Chinook: These are the warm and dry winds on the eastern side of the
rocky mountains in Wyoming and Montana (western USA).

c) Sirocco: Hot and dry wind blowing from the region of Sahara Desert is
known as the sirocco.

ii) Cold winds that originate due to the local factors are:

a) Mistral: The northwest cold winds
blowing into the western
Mediterranean basin from higher
elevated northern areas are known as
Mistrals.

b) Blizzard: Violent and extremely cold
winds common in the Antarctic region
are called Blizzards.

Blizzard

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PRECIPITATION

Precipitation is the falling of water in the form of droplets or ice or snow on the
Earth's surface. Very common forms of precipitation are:
i) Fine drops of water are the composition of fairly uniform precipitation.
ii) Precipitation of white and opaque grains of ice.
iii) A mixture of rain and snow.
iv) Precipitation in the form of small balls or pieces of ice.

i)
Heating of the land
surface causes air to rise
rapidly. The hot air here
actually expands and
becomes lighter. The
vertical movements and
turbulence as well as the
obstructions on surface
probably provide an
upward thrust resulting in the formation of clouds which causes rainfall.

ii)
Mountains or highlands
are barriers to the
moisture-laden winds,
which cause rainfall. This
is orographic rainfall.
Here, one side of the hill
that receives rainfall is
known as windward side
and the dry side is called the rain shadow or leeward side.

iii) The warm air mass rises upward, when the warm
fronts meet the cold fronts. This forms the clouds and results in rainfall by
hitting an elevated area. The border zone in between the two air masses of
different temperatures, is known as Front.

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Cyclonic or frontal
rainfall

 The thrust exerted on a surface from all
directions due to the weight of the air above it.

 It is the average weather conditions of a large area for a
long stretch of time.

 The heat emitted by the Earth's surface into the
atmosphere.

 The degree of hotness or coldness of an object.

 The state of atmosphere at any time denoting the short-
term changes of the atmosphere, relating to the temperature,
pressure, wind, moisture, cloudiness, precipitation and visibility.

 Winds that blow throughout the year in a
definite direction.

 The transmission of heat through the contact of any
other body.

 These are the seasonal winds that change their
direction in six months.

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 Weather is the state of atmosphere at any particular
time denoting the short-term variations of the
atmosphere in reference to the temperature, pressure,
wind, moisture, cloudiness, precipitation and visibility.
Climate is the average condition of weather of a large area
over a long period of time.

 Heat energy is transferred by four processes, namely
radiation, conduction, convection and advection.

 The three main Heat Zones are: Torrid (the hottest),
Temperate (the moderate) and Frigid (the coldest).

 Falling of water in the form of droplets or ice or snow to the
Earth's surface is known as precipitation. The three different
types of rainfall are: Convectional, orographic and frontal.

 The air pressure is a force on all directions because of the
weight of all the air just above it. The world can be classified
into four pressure belts, namely Equatorial low-pressure
belt, Subtropical high-pressure belts, Subpolar low-pressure
belts and Polar highs in both the Northern and Southern
Hemispheres.

 Permanent winds are the winds that blow throughout the
year in a particular direction. A few types of permanent
winds are: Doldrums, trade winds, westerlies and polar
easterlies.

TEST YOURSELF

A. Tick the correct answer:

1. The range of the torrid zone is from:

a. 30°Nto60°N b. 23 1/2°N to 23 1/2°S
c. 66 V2°N to661/2°S d. 90°N and 90°S

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2. Due to the heating of the land surface, the type of rainfall that occurs, is:
a. Orographicb. Cyclonic c. Convectional d. Sleet
3. In Switzerland, the warm dry winds of the Alps are called:
a. Sirocco b. Blizzard c. Chinook d. Foehn
B. Write in one-word:
1. At night the cool winds the blow from sea to land: __________
2. The study of climate: __________
3. Due to the movement of wind, the transfer of heat: __________
4. The study of weather: __________
C. What are the differences between:
1. Conduction and Convection
2. Weather and Climate
3. Trade Winds and Westerlies
4. Periodic Winds and Permanent Winds
D. Give reasons of why:
1. The Torrid Zone is the hottest zone?
2. In the Southern Hemisphere, the westerlies are strong?
3. Coastal area has a moderate temperature?
4. Canton of China is much cooler than Kolkata in winter?
E. Answer the following in brief:
1. What is the meaning of the term 'monsoon'?
2. How does the orographic rainfall occur?
3. What is lTCZ?
F. Answer the following in detail:
1. Which factors influence the temperature of an area?
2. What do you know about the pressure belts of the world?
3. Discuss about the different types of rainfall?

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G. Tick the diagram showing land breeze:

H. Activity:
1. Either suggest one experiment or give a real-life example to explain the

following:
a. On the Earth, the pressure is exerted.
b. With altitude, temperature increases.
c. Oxygen is necessary for life.
d. The direction of the wind.
2. Read todays wWather Report from the newspaper and write the details.

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The Earth's surface is occupied almost by 71% of water. 97% of this water is
found in the oceans and only 3% is fresh water which is found in the form of
snow and ice, rivers and lakes. The Earth is called the blue planet because of the
presence of water. Water is found in various forms.

WATER: A CYCLIC RESOURCE

Water always changes its
form. It evaporates from
the water bodies and goes
into the atmosphere as
water vapour, where it
again changes from vapour
to clouds due to the
condensation and then
again comes back to the
Earth as rainfall. Water
flows into rivers and then it
freezes to form the snow on the mountain peaks. This change of form of water,
following a regular process in all spheres of the environment, is known as water
cycle or hydrological cycle. This cycle involves three processes:

1. The water on the Earth's surface changes to water vapour and is
called evaporation. The water can also evaporate from the surface of the
leaves. This is called transpiration.

2. Condensation is the conversion of water vapour to its liquid
form. The water vapour becomes cooler as it rises upward in the air. This
vapour then condenses with the dust particles or any other matter present in
the atmosphere, and forms clouds.

3. The falling of water on the Earth's surface in either liquid or
solid form is called precipitation. When the cloud particles get too heavy to
stay suspended in the air, it falls down as precipitation. Due to this process,
the water once again reaches rivers, lakes, sea and under the ground. This
cycle of evaporation, condensation and precipitation is a continuous process
which is known as the water cycle.

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WATER SOURCES

There are mainly two types of water found on the Earth's surface:

1. Fresh Water
2. Saline Water

Freshwater lakes, rivers, atmosphere and underground are the
sources of fresh water. It has low contents of dissolved salts and is available in
very limited quantity. It meets the needs of living beings. Saline water cannot be
drunk by us. The demand for fresh water has rapidly increased due to the
increasing population.

The demand of water has led to a fall in the level of water table. Water pollution
is also a thing to think about. Water pollution is caused by the contamination of
water bodies. The agricultural and industrial waste disposal in the river is
another main cause of water pollution.

The seas and the oceans are the sources of Saline water. This
water cannot be used for drinking purposes as it contains dissolved salt. 97% of
the water is available in this form.

IMPORTANCE OF OCEANS

Saline water though not fit to drink, has its own importance. It is the basic
necessity of the aquatic life. Various species of aquatic plants and animals are
found in the sea. Seafood is the staple diet in the coastal areas. It is also the
source of one of the oldest modes of transportation. Sea is also the source of
salt. Why do the oceans have salt? Salt or sodium chloride, comes from the land.
While the rivers flow through land and rocks, they carry the sediments and
deposit them to oceans and seas. The sunrays are strong in the ocean and so the
salinity is high as the water gets evaporated and leaves the salt in the ocean. This
salinity gets reduced around the equator due to heavy rainfall which also results
in addition to the fresh water into the sea and the ocean.

About 35 grams of salt is dissolved in every kilogram of sea water.
The Dead Sea situated in Asia has the highest salinity in the world.

The five oceans in the world are the Pacific Ocean, the Atlantic Ocean, the Indian

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Ocean, the Arctic Ocean and the Southern Ocean. The largest ocean in the world
is the Pacific Ocean whose ocean surface is unstable. The surface of the ocean
water experiences continuous movements which can be broadly classified as
follows:
1. Ocean currents, 2. Waves, 3. Tides

The ocean currents are the continuous movements of water due to the wind
movement, pressure gradient, coriolis force because of the rotation of the Earth
and temperature variation and salinity.
The ocean currents travel long distances and they result in climatic impact. Most
of these are narrow and as swift as about 10 km/hour. The drifts are very broad
ocean currents. Based on the temperature, there are two types of ocean
currents:

i) These currents normally travel from the warm equatorial
regions to the cold polar regions. For instance, the Gulf Stream is a strong
warm water current generating from Mexico which goes into the Atlantic.

ii) These currents travel from the cold regions of poles to the
warm equatorial regions. For instance, the Humboldt Current which
originates from the southern tip of Chile and moves to North Peru along the
western coast of South America.

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Ocean currents play a very important role in
climatic distribution and other different economic activities:
 They affect the temperature of the coastal regions.
 Warm currents increase the moisture content in the winds and they result in

heavy rainfall. Cold currents on the other hand make the climate dry. That is
why most of the deserts are found in the western parts of the continents,
where the cold currents flow.
 The regions where cold and warm currents meet:
 Develop fog, which creates problems in navigation.
 Are the best fishing areas of the world.
 These Ocean currents also aid the sailors, sailing along the current. This
actually assists them to move much more faster.

The rise and fall of water on the surface of the oceans are called waves. The rise
is called the crest and the fall is known as the trough. Wavelength is the
horizontal gap between two crests. On the other hand, the wave height is the
vertical gap between the crest and the trough. Huge amount of energy is
generated by these waves and they are known as wave energy.

Tsunamis are the waves which are very massive in height, almost 20-30 metres
high. They result from the volcanic eruption or the earthquakes, originating from
under the sea or ocean. 'Tsunami' is a Japanese word which means harbour
wave. Tsunami occurs frequently in Japan due to the tectonic activities on the
ocean floor.

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CASE STUDY: JAPAN DEVASTATED: EARTHQUAKE

FOLLOWED BY TSUNAMI (11 MARCH 2011)

An undersea earthquake,
which measured almost 8.9
on the Richter scale, hit
Japan's northeast coast and
created Tsunami. The waves
were almost 23 feet high. In
few minutes, towns,
buildings, cars, roads and
other infrastructure were all
wiped away. The nuclear power plant in Fukushima Daiichi Nuclear Power
Station failed due to this. On 12 March 2011, the situation got worse because of
the explosion in the reactors of the Power Plant. 30 km area around it was
immediately evacuated. Japan was in major crisis due to the huge death toll and
loss of infrastructure.

At a news conference on 13th March 2011, Sunday, Prime Minister
Naoto Kan explained the importance of the situation. "I think that the
earthquake, tsunami, and the situation at our nuclear reactors make up
the worst crisis in the 65 years since the war. If the nation works
together, we will overcome," he said. To aid in the relief effort, 100,000
troops were called by the government. It was the largest deployment
seen after the World War II.

The ocean tides are the rise and fall in the level of sea water alternatively
because of the gravitational pull of the Moon and the Sun and also because of
the rotation of the Earth. The sea water rises and falls twice every day at a
regular gap of time. There can be high tides, when the level of water rises or
there can be low tides, when the level of water level falls. Tides are of two kinds:

i) The gravitational pull of the Moon and the Sun gets combined
during a New Moon or Full Moon, when the Sun, the Moon and the Earth are
in a straight line. Because of the gravitational pull of both the Sun and the
Moon, the high tides are formed which are called spring tides.

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Spring tide & Neap tide

ii) During a Half-Moon day, the Moon and the Earth come at a right
angle when the impact of the gravitational pull is not very high. So the tides
do not rise very high during this time and are called neap tides.

The first tidal power station was built at France
in the name of Ranee Tidal Power Plant.

The tides are very important for navigation and are also helpful in catching fish.
At the time of high tides, the fish comes near the coast which makes easier for
the fishermen to catch them. Salt is made during the period of high tides.
Nowadays, electricity is also generated from the tidal energy. So, High tide is also
used to generate electricity. Japan, U.K., Canada, etc. have set up many tidal
power stations.

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 71% of the Earth's surfaces is occupied by water and
thus it is so called the "blue planet".

 The change of form of water and its distribution in all
the spheres of the environment is called the water cycle.

 Fresh water is found in freshwater lakes, rivers, and
atmosphere and even from under the ground which has a
very low concentration of dissolved salts.

 The seas and the oceans are the sources of saline water.

 Ocean currents are formed from the continuous movement
of water due to: wind movement, pressure gradient, Coriolis
force because of the rotation of the Earth and temperature
variation and salinity.

 Depending on the temperature, there are two types of
ocean currents: warm currents and cold currents.

 The wave can be termed as something like a water ridge in
between the two depressions.

 The alternate rise and fall in the level of sea water is
because of the gravitational pull of the Moon, the Sun and
the rotation of the Earth.

 The change of water into vapour due to heat.

 The procedure of cooling of the vapour into liquid
form.

 Large water bodies of saline water on the Earth's surface.

 Rise and fall of water on the ocean surfaces.

 Very high waves caused due to the tectonic activity
under the Earth's surface.

 High tides caused due to the gravitational pull of the
Sun and the Moon during the New Moon.

 Low tides caused due to the gravitational pull of the
Sun and the Moon during the Half-Moon.

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TEST YOURSELF

A. Tick the correct answer:

1. The water level which is under the Earth's surface, is called

a. water table b. wells c. saline water d. wave

2. Another name for the harbour wave is

a. current b. tsunami c. port d. tide

3. Water that is moving from the polar region to the equator, is called

a. cold current b. tides c. tsunami d. warm current

4. On the Earth, the percentage of available fresh water is

a. 3 b. 97.25 c. 5.25 d. 11

5. Due to the gravitational pull of the Moon and the Sun and rotation of the
Earth, the alternate rise and fall in the level of sea water is called

a. tides b. waves c. tsunami d. currents

B. What are the differences between:

a. Fresh water and saline water

b. Warm currents and cold currents

c. Springtides and neap tides

d. Current and tide

C. Give reasons of why:

1. The salinity of ocean water decreases at the equator?

2. On the western part of continents, the deserts lie?

3. The high tides are caused by the New Moon?

D. Answer the following in brief:

1. What are the sources of freshwater?

2. What do you mean by the term "tsunami"?

3. Define ocean current.

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4. Which factors affect the movement of currents?
5. How are the tides formed?
E. Answer the following in detail:
1. What is the importance of the oceans?
2. Describe different types of currents.
3. With the help of a diagram, give the structure of waves.
4. What is the significance of ocean currents?
5. Discuss the statement, "Water is the basis of survival".
F. Label the water cycle:

G. Activity:

1. Gather some information about Japan Tsunami of 2011 with the help of
newspaper cuttings and internet and make a collage of it.

2. Show the processes of evaporation and condensation with the help of an
experiment.

3. On the outline map of the world, label the major oceans.

4. Write a brief essay on the pollution of the Yamuna River and the necessary
steps to clean it. Do not forget to give a suitable title to your essay.

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Trees or plants that grow naturally in a region without the human interference,
makes up the Natural vegetation. This can be classified into three categories,
namely forests, grasslands and shrubs. The existence of natural vegetation has a
very vital necessity of our planet.

HOW PLANTS ARE USEFUL

1. To form food, the plants take in carbon dioxide. So, removal of plant would
mean presence of the excess of carbon dioxide in air.

2. Plants are the source of many essential things like wood, timber, rubber,
medicines etc.

3. Plants help in rainfall by the process of transpiration, when the water gets
evaporated from the plants’ surface.

4. Animals and humans depend upon the plants for food.
5. Animals live in forests.
Various physical and climatic factors like soil, slope, rainfall, temperature and
humidity work behind the existence of the plants. For example, the forests grow
well and are generally found in the hot and humid climate. In dry climate, one
can find only shrubs. Again, grasslands are found in the regions of moderate
rainfall.

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FOREST

Forest is an area of high concentration of trees which comprises of trees,
shrubs, herbs and also animals. The existence of natural vegetation and wildlife
at the same time in the same geographical and climatic area is called a biome.

The world comprises of the following biomes, which have different types of tree
and animal species:
1. Tropical Evergreen Forests / Rainforest
2. Tropical Deciduous Forests
3. Temperate Evergreen Forests
4. Temperate Deciduous Forests
5. Mediterranean Forests
6. Tropical Grasslands
7. Temperate Grasslands
8. Desert Vegetation
9. Tundra Vegetation

The evergreen forests always remain green because all the trees here, do not
shed their leaves at the same time.

i) These forests are found in between 10°N and 10°S latitudes like in
the areas of Amazon and Orinoco river basins in South America, the Zaire
Basin of Africa and the Southeast Asian countries like Malaysia, Indonesia,
Vietnam, New Guinea and parts of Philippines.

ii) The climate here is hot and humid and the average annual rainfall
here is 65-75 inches.

CANOPY
It is the upper layer of a group of
trees, formed by the crown of trees.

iii) Hardwood and
broad leaves are the main features of
the trees found here. They form a thick
canopy. The types of trees found here
are: Ebony, mahogany, rubber,
rosewood, etc. As the forests are dense
and many varieties are found

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intermixed in a small area of land, the plants here cannot be easily exploited
for commercial use. These forests are known as "Earth's lungs" because they
are the source of 28% of the world's total oxygen turnover.

iv) Different species of fauna are also found in
these forests. Animals like Monkeys, apes, bats,
lizards, pumas, jaguars, etc. are seen here. Amphibians
like alligators, crocodiles, turtles and snakes are found
in these swampy areas.

i) These forests can be seen in the tropical region, ranging from 5°N/S
to 20°N/S latitudes. These forests spread over the countries like India,
Pakistan, Bangladesh, Sri Lanka, Myanmar, Central America, some parts of
Brazil, east Africa and northern Australia.

ii) These forests are commonly known as the monsoon forests as they
spread over the Indian subcontinent and receive monsoonal rains. The
average rainfall here is 150 cm and the temperature here ranges between 20°
C and 45°C.

iii) These types of forests are

always less dense here than the evergreen forests.

As the sunlight easily penetrates into the forest due

to the absence of canopy these forests are

characterized by the dense undergrowth of small

trees and shrubs. Because of the less intermixing of Sunderban Forest
plant species, such forests have high commercial

value. Teak, sal, sandalwood, bamboo, shisham, etc. are the types of tress

found here. The mangrove forests can mainly be seen in marshy and wet

delta area of Sunderbans. These are also known as tidal forests as they are

found in the abundance of inter-tidal zones near the

delta regions. These forests shed off their leaves in the

dry season.

iv) Monkeys, bears, deer, rhinoceroses,
leopards, snakes, elephants, etc. are the main animals
found here.

i) Along the eastern coastal lines of the continents, the temperate
evergreen forests are found which actually lie in the temperate regions of

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south-eastern areas of China, Japan, USA, Brazil, Uruguay, Australia and New
Zealand.

ii) Dry summers and wet winters are the types of climate that prevails
here.

iii) Both hardwood and softwood
trees can be seen here. They are valuable in terms
of production of timber. The typical type of trees
found here are Oak, pine, eucalyptus, acacia,
camphor, bamboo and mulberry.

iv) The animal species found here are Rodents like
mice, squirrels, porcupines, beavers, etc. These are the
common species of animals seen here. Animals like deer,
monkeys, and antelopes are also found here. Forests of China
are famous for the giant panda.

i) North-western USA, north-eastern China, western Europe, New
Zealand and southern Chile are the cool climatic regions which are famous for
the Temperate Deciduous Forests.

ii) As already said, the climate here is cool and experiences moderate
rainfall of 70-80 cm and has an average temperature of 20°C.

iii) These are not very tall trees
but they have thick trunk and broad leaves. The
special features of these trees here are that
after shedding their leaves in the autumn, they
remain leafless throughout the entire winter
season. Oak, ashes, maple, sweet gum, cherry,
etc. are the main trees found here. It is also noteworthy
that shrubs like rhododendrons and huckleberries are also
found here.

iv) Animal species that are found here are mainly
foxes, deer, wolves, wild cats, etc.

i) Located between 30° and 45° latitudes in both the hemispheres, are

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the Mediterranean Forests. They are mainly spread over the coastal parts of
Europe, Africa and Asia, surrounding the Mediterranean Sea, and also in
some areas of California, Chile and Western Australia.

ii) Dry summers and mild wet winters make the main climate of this
region.

iii) Dense forests of evergreen
trees of medium height having small but broad
waxy leaves with thick barks and long roots are
the characteristics of these forests. Due to this,
they can withstand the dry summers. The trees
found here are mainly Oak, fig, pine, cedar, fir,
etc.

This region is also famous as the Orchard of the Earth because of the fruit-
bearing trees like, oranges, olives, etc. and also for the cultivation of grapes.

iv) Varieties of animals like deer, rabbits,
squirrels, foxes, lizards, snakes, etc., are found here.
Most of the forests have been cut down to make land
for agricultural and non-agricultural uses for which
not many wild animals are found here. In fact, more
of domestic animals like cattle and sheep are found here.

i) Coniferous forests can be found in the United States, Canada, Europe,
and Asia. The northern Eurasian coniferous forest is called the Taiga, or the
boreal forest. Other types of coniferous forest occur at various elevations in
the Rocky Mountains of North America, in Central America, and in eastern
Asia. They are known as subalpine and montane forests. The light-coloured,
usually acidic soils of coniferous forests are called podzols (podsols).

ii) Temperate coniferous forests are found in the temperate regions of
the world with warm summers and long winters and moderate to high annual
precipitation to sustain a forest.

iii) These are mostly evergreen
forests consisting of the cone-bearing or
coniferous trees, e.g., spruces, hemlocks, pines
and firs, with needle-like or scale-like leaves with
a waxy coating to protect from the damage due to

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snowfall. These softwood trees are able to survive in cold temperatures and
in acidic soil. Mosses, liverworts, and lichens cover the forest floor.

iv) A few cold-blooded vertebrates, such as
snakes and frogs, are present because of the low
temperatures. The birds here include woodpeckers,
crossbills, warblers, kinglets, nuthatches, waxwings,
grouse, hawks, and owls. The prominent mammals
include shrews, voles, squirrels, martens, moose,
reindeer, lynx, and wolves. Mosquitoes, flies, and other insects are common
inhabitants of the coniferous forest. A number of invertebrates such as the
earthworms and the leech are abundant in the soil.

Deciduous trees Coniferous trees

They shed their leaves in autumn. They are mostly evergreen trees.

They are hardwood trees. They are softwood trees.

They have broad leaves. They have small, waxy and cone-
shaped leaves.
Some examples are: Oak, beech,
apple, etc. Some examples are: Pine, fir and
spruce, etc.

GRASSLANDS

The huge areas covered with short and tall grasses having few trees are called
the grasslands.

i) Ranging between 10° and 20° latitudes is the area of Tropical
Grasslands which are also known as the Savannas. They are generally found in
the regions of northern Africa, northern Australia, the Brazilian plateau,
Colombia and Venezuela.

ii) The climate is hot here and the
temperature does not fall more than 20° C,
even in winters. The region has an annual
rainfall ranging from 25 cm to 75 cm.

iii) These are populated with

Savannas

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the thick and the coarse grasses about 3-5 metres long. Here the trees are
scattered and widely spaced so that one can easily move in these grasslands.

iv) The tall grasses here help the animals to
camouflage easily. Grasshoppers, termites and beetles are
some of the insects found here. Also, African elephants
and African cats in Africa; Kangaroos and Wallaby in
Australia; and Asian water buffalo and Asian elephant, etc.
in India; are very common here.

i) Found in the interior of the continents

like in Central Asia, North and South America

and South Australia, are the Temperate

Grasslands. They have different names in

different places. For example, in Eurasia they

are called steppes, in Argentina and Uruguay

they are known as pampas, in North America

they are named as prairies, while they are Pampas

known veldts in South Africa and in Australia they are famous as the downs.

In India, they are found in the high mountain fields of the Himalayas.

ii) Hot in summers and cold in winters are the feature of these areas.
The annual average rainfall here is in between 10 and 20 inches.

iii) The grasses here are normally short but some are as tall
as nearly 2 metres. Being rich in nutrients, they provide good grazing grounds
for cattle. As it is a dry area where sufficient moisture is not available for the
growth, the trees are rarely found here.

iv) These regions are famous for the
extensive cultivation and dairy farming, so cattle
and sheep are mainly found here. Zebra,
antelopes, buffaloes, hyenas and snakes are
other animals seen here.

SHRUBS

The plants that are smaller than the trees, are known as Shrubs.

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i) Desert vegetation can be seen in the
areas of hot deserts like Sahara, Kalahari,
Atacama, Great Australian Desert, Arabian
Desert and the Thar Desert.

ii) These areas have hot summers and Kalahari
dry winters and the rainfall is very scanty.

iii) The presence of only shrubs and scrubs are the main
feature of this type of vegetation where tall and medium-sized trees are
almost absent. Here the bushes are characterized by the thorny leaves, long
roots, waxy stems and thick barks which help them to adapt to the typical hot
and dry conditions of this place. Cactus, acacia and date palms are the
examples of little vegetation found here.

iv) The camel are commonly known as
'the ship of the desert'. The have padded feet
which enable them to walk on sand. It also has a
hump to store water. Desert fox, antelopes,
snakes, lizards, rodents, etc. are the other
animals, found here.

Meerkats

i) The Tundra is spread over the Arctic
Circle in the areas of northern part of
Canada, Alaska, Greenland and northern
Europe.

ii) The climatic conditions here are Tundra Region, Greenland
very severe as the temperature is very low
here. Throughout the year, the snow covers
the whole ground in this region.

iii) These areas do not possess much of vegetation. The
small flowering plants, mosses, lichens and common plants like Arctic willow
grow here in tundra region. They are of only a foot high and have a shallow
root system to sustain in the windy situations.

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iv) The animals of this region usually have a
thick layer of fat on their body, which protects them
from the severe cold. Reindeer, polar bear, musk dogs,
etc. can be seen here.

DEFORESTATION

Deforestation is the depletion of tree cover from the earth’s surface which is a
big threat to the world forests. The trees are being cut. The forest land is cleared
for different reasons like setting up and developing residential areas, commercial
areas, industrial areas, road and, rail networks, etc. The environment of these
areas as well as the animals are facing a massive threat due to this factor. The
natural habitat of the area is destroyed.

As forests are the lifeline of our planet, there is always a great need to save the
forests. It is important to reforest i.e., to replant trees in respective places after
cutting down trees. Planting trees in new areas are also necessary which is
known as afforestation. "Save trees, Save humanity" was rightly said by the
famous activist and environmentalist, Sunderlal Bahuguna.

 Trees, grasslands and shrubs which grow
naturally on the Earth’s surface.

 Huge area covered with trees, plants and other natural
vegetation which is also a shelter to the animals.

 The co-existence of natural vegetation with wildlife in one
and same geographical and climatic region.

 An area covered mainly with short and tall grasses and
very few trees.

 Cutting down and removal of the forest trees for
different uses.

 The forest which remains green all over the year,
due to the availability of enough moisture.

 A stunted tree or shrub.

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 The natural vegetation can be classified into three main
categories : forests, grasslands and shrubs.

 The dense population of trees in an area is called a
forest.

 The existence of both the trees and the animals in a same
geographical and climatic area is called a biome.

 Evergreen forest remains green throughout the year because
all the trees do not shed their leaves at the same time
together in the same season.

 The various types of natural vegetation in the world can be
classified into Tropical Evergreen Forest, Tropical Deciduous
Forest, Temperate Evergreen Forest, Temperate Deciduous
Forest, Mediterranean Forest, Tropical Grasslands,
Temperate Grasslands, Desert Vegetation and Tundra
Vegetation.

 The forest land is cleared for various purposes like
developing residential and commercial areas, setting of
industries, building of roads and rail networks, etc.

TEST YOURSELF

A. Tick the correct answer:

1. Which of the following can be called the lungs of the Earth

a. Tropical Evergreen b. Temperate Evergreen
c. Tropical Deciduous d. Tundra

2. The forests that are found in the Amazon and Zaire Basin, are

a. Tropical Evergreen b. Tundra
c. Temperate Deciduous d. Temperate Evergreen

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3. Tropical grasslands can be found between

a. 10° and 20° latitudes b. 20° and 40° latitudes
C. 30° and 50° latitudes d. 20° and 50° latitudes

4. The high steep rocky coast which rises vertically above the sea water is
known as

a. sea cave b. sea cliff c. valley d. barchans

5. The Pampas are seen in

a. Argentina b. Australia c. Uruguay d. South Africa

B. Answer in one-word:

1. A huge land that is covered under the natural vegetation: _____________

2. In desert areas, the vegetation found: _____________

3. The animals’ process of self-protection: _____________

4. Depletion of the forest cover: _____________

5. The tropical grasslands: _____________

C. Give reasons of why:

1. The tropical evergreen forests cannot be commercially exploited?

2. Mediterranean forests are known as the "Orchards of the Earth".

3. Most of the bushes have thorny leaves, long roots, waxy stems and thick
barks in the desert

4. Animals have fur and layer of fat on their body in Tundra?

D. Answer the following in brief:

1. Define biome.

2. Name the different types of trees that are found in a tropical evergreen
forest.

3. Which common animals are found in the tropical grasslands?

4. Write the location of Mediterranean forest.

5. What do you mean by a tidal forest?

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E. Answer the following in detail:
1. What is the importance of trees?
2. What are the characteristics of a tropical deciduous forest?
3. Define deforestation. What are its causes?
4. What do you know about the natural vegetation of hot and cold deserts?
5. Discuss the features of temperate forests.
F. Activity:
1. Write the differences between temperate and tropical grasslands.
2. Show deforestation by preparing a model.
3. Visit a zoological garden or a wildlife area. Now write about the animals you

have identified there.

Giant Pandas: an almost extinct species

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The early men wanted to sleep in
peace. They needed protection from
the animals. He also wanted to cook
tasty food. Not only from the animals,
he also needed the protection from the
natural calamities.

A settlement is such a place which has
been previously uninhabited but later
people have established a community
out there. The human settlements have
evolved over a period of time. The early
men were gatherers and wanderers.
They started living a sedentary life with the beginning of agriculture. They used
locally available materials to build their houses. But these settlements got
destroyed because of the natural calamities like floods, earthquakes, volcanoes
etc. These settlements were built, got destroyed and then again rebuilt. Near the
river valleys, most of the early civilizations have developed. The reasons behind
the development of the civilizations beside the river valleys are mainly because
the fertile soil and enough availability of water. Even the existence of older
civilizations and their settlements are found through the excavations of various
sites. The suitable example can be the Indus Valley civilization. The occupants of
this civilization were excellent town-planners. The city had a rectangular pattern
with well-ventilated houses. The well-planned drainage and sanitation facilities
were the main features of these houses. They also had large dockyards and high
citadels.

In every decade, the Census of India conducts a population survey.
Numerous data on population and their characteristics are operated
by it.

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SETTLEMENT

A settlement can have both kutcha and pucca houses. The kutcha houses have
weak structures. They are made up of locally available materials like mud, straw,
thatch, cloth etc. The pucca houses, on the other hand, are made up of bricks,
wood, iron and other concrete materials.

On the basis of the type of structures and their nature of existence, the
settlements can be classified into two types - the permanent settlements and the
temporary settlements. The permanent settlements are built with a proper
layout plan. Most of the modern world settlements are the permanent
settlements. The settlements which are occupied for a short period of time are
known as the temporary settlements. These settlements are generally built in
hilly, forest and desert areas.

On the basis of population, economic activities and the available facilities,
settlements again can be classified into two types. According to the census of
India, the settlements are classified as The rural settlements and The urban
settlements.

Rural settlements are those
areas which have low population and have
kutcha or semi-pucca houses. People, living in
rural settlements are engaged in primary
activities. They also get very limited facilities.
Villages and hutments are considered to be
rural settlements. Hamlets III are also the rural
settlements which are smaller than villages.

According to the
Census of India, those areas are
considered as urban when:

It is a statutory place where
municipality, corporation, cantonment
board or notified town area committee
are available.

Its population is more than 5000. Mora than three fourths of the male
population is engaged in non-agricultural activities.

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Urban areas consist of pucca houses, road, electricity, transport and
communication facilities, etc.

A small town, a city or a mega polis can be considered as the urban settlements.

Settlement is not just about people. It also counts houses, markets, economic
activities, schools, hospitals and other facilities available in an area.

NATURE OF RURAL SETTLEMENT

Rural settlement generally means village. There are many green fields where
crops, vegetables and fruits are grown. Many commercial flowers also can be
found there. It has either pucca or semi-pucca houses and the roads are very
narrow. Some rural settlements have electricity too. But it cannot provide
enough scope for higher studies and enough job opportunities.

The types of rural settlements depend upon various factors. The prime one is the
physical factor of an area. The types are determined by the slope, soil, climate,
and fertility. There are mainly three types of settlement:

i) These settlements are also known as
agglomerated settlements. They consist of the houses which are closely
located to each other. The roads in these settlements are narrow and
winding. These settlements are found in plain and fertile areas. These
settlements are typical in the river valleys. Most of the river plains of
monsoon Asia present compact settlements. In these settlements, all houses,
farm structures and other buildings are closely settled.

ii) Semi-clustered settlements are also known as
partially agglomerated settlements. In these settlements, the houses are
situated along a road or stream. Such settlements are found along the
streams in Manipur and in Mandla, Raigarh and Balaghat Districts.

Clustered Settlement Semi-clustered Settlement: Scattered Settlement

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iii) These settlements are also known as
isolated settlements. In these settlements, the houses are scattered and
dispersed over a large area. Such settlements are found in hilly, desert and
forested areas. Such patterns are also common in the hills of Jammu and
Kashmir, Tamil Nadu and Kerala.

The houses in rural areas are arranged in different patterns. Mainly four patterns
can be found in rural areas:

i) A linear pattern is common along main
roads or rivers. It has a single row of houses arranged in
the main artery. The houses are located in this way
because people prefer to live along the transport routes
and where there is the availability of enough water.

ii) In this pattern, houses develop along a
number of streets that radiate from the villas. Generally,
such patterns occur around a well or around the sources
of water (like ponds).

iii) The most common pattern in rural
settlements in India is the rectangular pattern. It
generally evolves around the rectangular shape of fields.

iv) These patterns are found around
ponds, chaupal or well. Even, it is found near the oasis
of a desert area. An oasis is a fertile spot in a desert
where water is found.

URBAN SETTLEMENT

An urban area is a location characterized by high population density. Urban areas
are the cities, towns or conurbations. People living in Urban areas get enough
scope for higher studies and job opportunities.

A metropolis is an urban area which is a significant, economic, political and
cultural centre for a country and an important hub for international
communications. Delhi is a metropolis and the capital city of India. An urban area
has more than one million populations and Delhi has almost one million
residents. The Census of India classifies the towns in six categories on the basis of
population. They are:

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 Class 1 towns: Population is more than 100,000
 Class 2 towns: Population is in between 50,000 to 99,999
 Class 3 towns: Population is in between 20,000 to 49,999
 Class 4 towns: Population is in between 10,000 to 19,999
 Class 5 towns: Population is in between 5,000 to 9,999
 Class 6 towns: Population is less than 5,000

The towns are classified into five types on the basis of dominant functions or
activities. They are:
i) All the capital cities where most of the administrative

buildings are set up and all administrative functions take place come under
this category. Delhi, Mumbai and Ahmedabad are considered as the
Administrative towns.
ii) Towns like Dehradun, Meerut, Vishakapatnam, etc. have
defence facilities, cantonments and armed forces. So, these are called the
defence towns.

Nalanda was the world’s biggest university. The
eminent Buddhist monk and celebrated Chinese
traveller, Hiuen Tsang studied at Nalanda in 633 AD.

iii) Educational and cultural towns include
Haridwar, Varanasi, Roorkee etc. They are famous for education, religion and
culture.

iii) Towns that have manufacturing industries are called
industrial towns. For example, Jamshedpur is famous for locomotives and
Rourkela is famous for steel plant.

iv) The junction towns are those towns which are located on the
railway junctions or crossroads of major roads. A famous example is Mughal
Sarai, a town in Uttar Pradesh.

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TRANSPORT

Transport or transportation is the movement of people, goods and animals
from one place to another. Animals were the earliest modes of transport.
Animals like horses, donkeys, mules, etc. used to carry both people and goods.
The usage of the carts began with the invention of the wheel. Transport became
faster with the invention of steam and oil-powered vehicles. There are four
modes of transport like Roadways, Railways, Airways and Waterways.

ROADWAYS

The most common mode of transport is the roadways. It includes trucks, buses,
private cars, taxis, auto-rickshaws, two-wheelers, etc.

i) They are easily available in almost every place.

ii) They are the faster and cheaper mode of transport for short distances.

iii) They give door-to-door services.

iv) In hilly, forested and desert areas, roads are
difficult to construct.

Roads can be classified as follows:

i) Road rollers and coal
tar are used to make the pucca or metalled
roads. These roads are broad are built in
towns and cities.

ii) These roads are
not properly made. They are made by clearing
the forest lands. These roads are generally
narrow and are built in villages.

The longest road of the world is located in India.
It is 4000m above the sea level. It is connected
from Manali to Leh in Himachal Pradesh.

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Roads can also be classified on the basis of their connectivity:

i) They connect the state capitals.

ii) The remote areas along the borders of the country are
connected by the border roads.

iii) These highways connect the districts as well as the state
capitals.

iv) Various towns in a state are connected by it.

v) Villages are connected through the village roads.

RAILWAYS

Another popular means of land transport is
railway.

i) They are the most common land
transport, mainly for the long distances.

ii) They cover long distances in lesser time
than buses.

iii) A lot of passengers and goods at a time can be carried by these railways.

iv) The stations are connected to each other by these railways.

v) They do not give door-to-door services like the roadways.

The railways can be classified into two like steam engines and Electricity or Diesel
or Trackside systems (like lasar radar type) on the basis of fuel.

On the basis of transported things, the railways are classified into: Passenger
trains and Freight trains. While the Passenger trains carry people, freight rains
carry goods.

It can also Be divided into two - Narrow gauge and Broad gauge on the basis of
gauge. While in narrow gauge, the distance between the two rails is very less, in
broad gauge, the distance is wider. Narrow gauge can be easily constructed.
They are even cheaper. The Standard gauge,i.e.,1435 mm broad rail tracks are
used by nearly 60% of the world.

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The railways which connect one end of the continent to another end , are called
trans-continental railways. Some of them are:

i) The Trans-Siberian Railways connect St. Peterburg with Vladivostok.

ii) The Australian Trans-Continental Railways connect Sydney with Perth.

iii) The Orient Express connects Paris with Istanbul.

iv) The Canadian-Pacific Railway connects
Vancouver with Montreal.

The fourth largest network of railways in the world
is found in India. Even cities like Delhi, Kolkata and
Bengaluru have the metro facility.

AIRWAYS

Wright brothers, Orville and Wilbur
have invented the aero plane in
December, 1903. This brought a
strong revolution in the transport
industry and global economy.

i) This is the fastest mode of transport.

ii) It is an expensive mode of transport, much more expensive than the
roadways and railways.

iii) As it is difficult to construct airport in hilly or mountainous areas, this facility
is not available in every places.

iv) Lesser number of goods or persons than railways is carried by this mode.

v) For international travel, it is the most preferred means of transport.

vi) It helps to reach the remotest and most inaccessible areas.

On the basis of the carried goods, the aero planes can be classified into three:
Passenger planes, freight planes, and cargo planes. In many countries, the
government own and operate the airlines. These are called National airlines.
Indian Airlines and Air India in India are the two examples of national airlines.

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The private airlines are operated and owned by the private entrepreneurs. Some
examples are Airways, Spice jet, Kingfisher, etc.

On the basis of the area of operation, the flights are again classified into two -
Domestic flights and International flights. While domestic flights operate within
a country, international flights operate across the national borders.

WATERWAYS

One of the oldest ways of transportation is
the waterway.

i) They are the most cheapest and widely
used means of transport.

ii) Only along the navigable water bodies,
they are available.

iii) A bulk of goods across the seas is carried by the waterways.

There are two types of waterways:

i) Navigable rivers, lakes and canals are included in it. The
navigable rivers are Nile, Amazon, Ganga etc. The busiest inland waterways
are the Great Lakes between the USA and Canada.

ii) The major trade routes in today’s world are the sea-routes. The
busiest routes in UK are the Far East (Japan and China) via the Mediterranean
Sea, Suez canal and Malacca Strait. The other one that connects Western
Europe, the USA and Canada is the North Atlantic route.

COMMUNICATION

Communication is a process of exchanging information and ideas. Man as a social
being, interacts with others to gain knowledge and also to spread ideas and
information. In ancient times, people were informed by beating drums. Letters or
messages were first sent by the pigeons and then by the men on the horses
(doots).The ways have been developed over the years. The developed
technology and the invention of televisions and computers have made the
communication much more easier and effective. Today, we can communicate
with the others, living far away from us or may be in other countries through

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telephones or internet. Mass communication is a common medium which
spreads information, news and ideas. It is a popular mode by which the masses
are informed. Mass communication includes the print media like newspapers,
magazines etc. and also the electronic media like television, radio and internet.

The revolution in the field of information technology had occurred with the
invention of satellites. The speed of information flow has been upgraded
because of the satellite technology. Through the television, people get the daily
news. Television and radio become more popular than the newspapers because
of its audio-visual facility. Moreover, newspapers are only for the educated
people whereas the television is enjoyed by everyone and even the illiterates.
The e-world is also gaining rampant popularity. e-world indicates the electronic
world of internet where a lot of online services can be availed. For example, e-
learning, e-commerce, e-trading, internet banking and even the e-newspapers
which are easily available for everyone. People can perform different activities
through internet like mailing, chatting, downloading movies, reading news and
listening to the music, etc. These facilities have made our life easier. With the
help of technology, we can save time and do a lot of things in lesser time.

We have come to know from the early chapter that the world today has become
a global village. Now a days, it has become very easy to send messages and
information to any part of the world at any time. It has brought the world closer.
Transport and the communication are the real pillars of development.

 A colony that is newly established.
 Related to the city life.
 Related to the village life and pertaining to be less-

populated.
 Modes of movement of people and the goods.
 A process of exchanging information and ideas.

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 A settlement is such a place which has been previously
uninhabited but later people have established a
community out there. It is of two types: Permanent
settlement and Temporary settlement.

 Settlements are classified into two by the Census of India:
Urban settlements and rural settlements.

 Rural settlements are the villages where population is less
than 5000.Here most of the people are engaged in
agriculture or in other primary activities.

 The population of urban areas is more than 5000.Most of
the people are engaged in non-agricultural activities.

 The four modes of transport include: Roadways, Railways,
Waterways and Airways.

 Communication is a process of exchanging information and
ideas.

 Mass communication is a common which spreads
information, news and ideas either through print media or
through electronic media.

 Transport and communication are the real pillars of
development.

TEST YOURSELF

A. Tick the correct answers:

1. The settlements that are found in hilly, forest and desert areas are called:

a. Permanent settlements b. Rural settlements
c. Urban settlements d. Temporary settlements

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2. Pillar of development is: c. Schools d. Technology
a. Computer b. Communication

3. Which among the following is not a defence town?

a. Dehradun b. Meerut c. Varanasi d. Vishakapatnam

4. Which is the biggest university in the world?

a. Nalanda b. Jaharlal Nehru University

c. Benaras Hindu University d. Jadavpur University

5. Which is the fastest mode of transport?

a. Aero plane b. Express trains c. Taxis d. Buses

B. Fill in the Blanks:

1. The electronic world of internet is called _____________.

2. One of the busiest sea routes of the world is via ___________.

3. ____________ ways are the cheapest means of transport.

4. ____________ is the name of a private entrepreneur which owns the private
airlines.

5. The busiest inland waterways are the ____________ between the USA and
Canada.

C. Differentiate the following terms:

1. Permanent and Temporary settlements

2. Compact and Scattered settlements

3. Metalled and Unmetalled roads

4. Roadways and Railways

D. Answer the following questions in brief.

1. Which cities in India get the facility of metro?

2. Define settlement.

3. Classify Roads on the basis of connectivity.

4. How many types of settlements are there on the basis of population?

5. What do you mean by the junction town? Give an example of it.

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6. How many modes of transport are there? Name them.
7. Classify the railways on the basis of fuel.
8. Name two major trans-continental railways.
9. What do you mean by the domestic and international flights?
10. Classify the towns on the basis of functions. Name them with atleast one

example.
E. Answer the following questions in detail.
1. What are the patterns of rural settlement? Explain.
2. Classify towns on the basis of functions or activities.
3. Write the differences between the metalled and non-metalled roads.
4. Write the characteristics of Railways.
5. What are the different types of airways? Discuss with examples.
6. How many types of waterways are there? Discuss them with examples.
7. What is mass communication? How much it is essential in today’s life?
F. Activity:
1. Name two early civilizations and their settlement patterns.
2. Name three industrial towns in India.
3. What do you know about Golden Quadrilateral?
4. What are the advantages of trackside system?
5. Name any three ways by which you can communicate with your friends and

relatives who stay far away from you.
6. According to you, which is a better means of communication-print media or

electronic media? Answer with enough logic.
7. Collect information on modern means of communication with the help of

newspaper cutting and internet.

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The natural vegetation and the animal life of a region are completely dependent
on climate. Let us now study the tropical and subtropical regions and their
dependence on the climate. We should also study how the vegetation and
climate are interrelated.

THE TROPICAL REGION

Near the equator, the tropical region lies. From 10 degree North to 10
degree South of the equator, it is extended. It is also named as the rainy tropic.
The rainy tropic is extended over the northern part of South America, the
northern part of Africa and south-east Asia. Over the Amazon Basin, the largest
tropical rainforest is extended.

In this region, the main keywords to the climate are warm, wet and
humid. As the rays of the Sun fall vertically on the equator throughout the year,
the temperature is very high. The prime features of this region are high humidity
and heavy rainfall. The average annual rainfall fluctuates. It varies between 60-
120 inches. The soil is not fertile enough because the top layer of the soil gets
washed away because of the heavy rainfall.

A CASE STUDY OF AMAZON REGION

The word Amazon is derived from a Spanish word which means “destroyer of
boats”. Now let us see why the area is named “Amazon”. Over the Amazon basin
of South America, this region is extended. The main feature of this region is the
dense forests with broad-leaved trees. It is spreaded over Brazil, Peru, Colombia,
Venezuela, Ecuador, etc. Almost 60% of the rainforests are there in Brazil.

In the Amazon river, there are almost eleven hundred
tributaries. In length, about ten tributaries exceed the Rhine
river. They carry more than double its volume of water.

The Amazon River drains the entire region. In the world, it is the second largest
river. This river rises from the Andes and it flows into the Atlantic Ocean. Your

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work is to find out the name
of the longest river in the
world. The Amazon river has
the largest river basin in the
world. This basin is about
70,00,000 square km.

The largest and the thickest
forests in the world are the
tropical rainforests of
Amazon. These forests have
evergreen broad-leaved
trees. There is thick
vegetation in this area
because of the constant rainfall and humidity. The average height of the trees is
between 100 feet and 150 feet. Here, the forests are dense and the trees form a
canopy over it. For this reason, the sunlight is not allowed to enter the forest
floor and thus limits the growth of grass and other vegetative cover. Moreover,
the interior of the forest is gloomy. In the daytime also, it is nearly dark. As the
forests are dense and impenetrable, they have little economic value.

These forests are rich in species both of
flora as well as fauna. The estimate says
that there are 2.5 million insect species,
10,000 of plants and around 2,000 birds and
mammals.

Some of the important trees which can be Palm Trees

found here include ebony, palm, rubber and cane. These

trees are the sources of hardwood timber. The tree, Balsa is

also found here. Balsa has the lightest wood. These forests

also provide rubber, cocoa, nuts, gum, wax, resins, etc.

Creepers and climbers are commonly found here.

Scarlet Macaw The animals like monkeys, jaguars, tapirs, pumas etc. are
included in the rich variety of wildlife. In these forests, many
reptiles like anaconda, giant turtles, alligators and crocodiles
are found. Varieties of birds like toucan, humming bird,

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scarlet macaw etc. are also seen in this forest.

Rainy tropics are actually very thinly populated

areas. In the Amazon Basin, the density is nearly 2

persons/sq km. The major population of Amazon Giant Turtles

lives in cities but a little native population still lives in the forest. It completely

depends upon forest and the production of forests for its living. It also depends

on fishing, hunting and gathering to get its food. The shifting cultivation is

practiced here. In this practice, the land is cleared first and then it is cultivated.

This practice is done in a very traditional way. The commercial framing is not

engaged in it. The whole crop is consumed. Seringueiros are the rubber tappers.

Latex is collected from the rubber tree and is converted into usable products.

Some tribes, living here are cattle ranchers.

A lot of cultural diversity is shown in the Amazon

Basin. The native people reside in simple wooden

houses or thatched huts of beehive shape. These

huts are named as maloca. The maximum numbers

of the Amazon tribes are highly influenced by the

Europeans. The Bororo tribes live in Southern

Maloca Hut Amazonia. The weather conditions are

comparatively dry here. As they are in contact with the Brazilian people, they can

speak Portuguese or Spanish and have also developed the material culture. Most

of the Korubu tribes still live in isolation. They are mainly hunters and they use

bows and arrows.

The scattered settlements in the

forested area are connected to the

Trans-Amazon Highway. Its length

is 5,3000 km. It is the third longest

highway in Brazil. Various isolated Bororo Tribes
regions with the rest of the country

are integrated to it. It is an additional development of the area. It has made

timber transport easier. At the same time, it has led to massive deforestation in

the area.

Density of Population = (Total Population of an
Area) / (Total Land Area in Square Miles /Square Km)

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SUBTROPICAL REGION

The subtropical region is extended from 10 degree North to 30 degree
South latitude. On the eastern sides of the continents, the wet subtropical
regions lie. Along with the Ganga and the Brahmaputra Rivers, the largest region
lies in Asia. This is named as the “Ganga-Brahmaputra Basin”.

In the wet zone, it is lied. In the monsoon period, most of the rainfall
takes place. From the east to the west, the rainfall gets decreased. The western
part of the region receives 60-80 inches of rainfall in each year and the eastern
part receives 80-120 inches of rainfall in each year. While the winters are cold
and dry in this region, the summers are hot and humid.

A CASE STUDY OF THE GANGA-BRAHMAPUTRA BASIN

The Ganga-Brahmaputra Basin is spreaded over India, Nepal, Bangladesh and
Tibet. It is the largest fertile plain in the world. The Ganga and the Brahmaputra
are the two main rivers of the basin.

In the Western Himalayas, the Ganga River is originated from the Gangotri
glacier. The two major streams named Bhagirathi and Alaknanda meet at
Devaprayag and they form the main stream of the Ganges. The Ganga is 2510 km
long. It passes through the mountains and the plains of northern India and it
finally enters to the Bay of Bengal. The Ganga basin is spreaded over the states of
Haryana, Uttar Pradesh, Uttarakhand, Bihar, Madhya Pradesh and West Bengal.
In Tibet, the Brahmaputra river is called Tsangpo. It is originated in the
southwestern Tibet. It passes from Arunachal Pradesh in India and here, it is
known as Dihang. Then it enters to Bangladesh and merges with River Ganga to
form the famous delta, called Ganga-Brahmaputra Delta. It is the largest delta in
the world.

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The Hindu mythology says that the Ganga was brought down to the
Earth from Heaven by the prayers of a famous king, Bhagiratha. The
Ganga was born from Lord Shiva’s jata. It came to the Earth to make
the land fertile and to wash away all the sins of people. This is why ,
the Ganga is called a holy and sacred river.

The main feature of this region is that it has tropical deciduous forests. These
forests are not very dense. Here, the trees shed their leaves annually. They do
not have the canopy. That is why, shrubs, herbs and grasses like floor vegetation
are found here. The trees like Sal, Peepal and Banyan are commonly found here.

In the delta region, the mangrove forests can be found. They are also known as
Sunderban forests. The trees like Sundari, bamboo, mangrove, date palm etc.
are widely found here. In Uttarakhand, Sikkim and Arunachal Pradesh, the
coniferous forests are found.

A variety of animal species like pythons,
elephants, leopards and crocodiles are noticed
here. Rhinoceros and tigers are widely seen.
Around 30,000 deer stay in the Sunderban delta.
The birds like eagles, kingfishers, woodpeckers,
etc. are found here. Fishes like rohu, catla and
hilsha are also available here. Two varieties of
dolphins like Irrawady dolphin and the Ganga River dolphin can also be seen
here.

The world’s most densely populated region is the Ganga basin. Around 400
million people are the resident of this region. Along the rivers, most of the big
cities and towns are located. Cities like Varanasi, Kanpur, Allahabad, Patna,
Kolkata and Guwahati are situated here. The rural population dominates this
area. The most common economic activity in the plain areas is agriculture. Soil,
here, is very fertile in nature. The availability of water throughout the year
encourages agriculture in the Ganga plains. Here, rice, wheat, grains, vegetables,
fruits and tea are widely grown. Some cash crops like cotton, jute, sugarcane,
oilseeds etc. are also grown here.

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Agro-based industry-Agro-based industries are those industries that
depend upon the agricultural output for raw materials like sugar mills,
textile mills, etc.

Apart from this agriculture, this region has also a huge industrial base. Different
industries, especially the agro-based industries, are found here. This area also
has jute mills, cotton textile mills, sugar mills, etc. As the area has conductive
agricultural conditions, the agro-based industries are located here.

The transport and communication network were well developed in the Ganga-
Brahmaputra Basin. A very common means of transport is the roadway. The
navigable channels are available in both the Ganga and Brahmaputra rivers. The
rail network connects most of the areas in this region. Kolkata is a busy port on
the Hooghly river. Most of the cities in this region have airports.

 The tropical region is extended from 10 degree North to
10 degree South of the equator.

 Warm, wet and humid climatic conditions are the main
features of this tropical region.

 Over the Amazon Basin, the largest tropical rainforest is
extended.

 The Amazon River has the largest river basin (70 lakh sq km)
in the world.

 Tropical forests are marked by the broad-leaved evergreen
trees.

 The Trans-Amazon Highway is the third largest highway
(5,3000 km long) in Brazil.

 The Subtropical region is extended from 10 degree north
latitude to 30 degree south latitude.

 While the winters are cold and dry in the subtropical region,
the summers are hot and humid.

 The Ganga-Brahmaputra Basin is spreaded over India, Nepal,
Bangladesh and Tibet.

 The world’s most densely populated region is the Ganga
Basin. Cities like Varanasi, Kanpur, Allahabad, Patna, Kolkata
and Guwahati are situated here.

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 The forests which consist of those trees that
retain their green foliage throughout the year.

 An area that is drained by a river and its tributaries.
 The plants which need support to grow upright.
 A dense crown which is created by the closely located

trees and their branches.
 A triangular alluvial that is deposited by a river before

entering into a sea.

TEST YOURSELF

A. Tick the correct answers:

1. Thick vegetation is found in the:

a. Tropical region b. Subtropical region c. Hilly areas d. Amazon basin

2. “Destroyer of boats” is the other name of:

a. Ganga basin b. Amazon c. Greece d. Ganga basin

3. Bird Toucan is found in:

a. The Amazon Basin b. Sunderban c. Thar desert d. Himalaya

4. Ganga Brahmaputra basin is not spreaded over this country:

a. India b. Nepal c. Pakistan d. Tibet

5. Bhagiratha is the name of a:

a. King b. Monk c. River d. Mountain

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