5.To locate places on topo sheets/
topographical maps, an arbitrary network
of vertical and horizontal lines is used. The
vertical lines that run across the topo sheet
are called Eastings. The horizontal lines are
called Northings. The network created by
these intersecting lines is called a grid. The
Eastings and Northings cross at points called
coordinates.
Coordinates are a set of two numbers that
are used to locate any point on a grid. One
number indicates the horizontal distance
and the other, the vertical distance. When
identifying the location of a place, the Easting
that lies immediately to the left of the place
is mentioned first, followed by the Northing
that lies immediately below the place.
Six-figure grid references are used to locate
a place with greater accuracy, or to locate a single point on the map, such as a post office, a police
station, a well, a temple or a bridge. To get the six-figure grid reference, each grid square is further
divided into 100 equal parts and the vertical and horizontal lines within the grid square are
numbered from 1 to 9. In a six-figure grid reference, the first three figures refer to Eastings and the
last three figures refer to Northings. In the given figure, the grid square 2314 has been divided into
100 equal parts, and the vertical and horizontal lines have been numbered from 1 to 9. Thus, the
six-figure grid reference for the spot height A, located in the grid square 2314, is 232146, where 23
is the Easting, 2 is the value of the line to the left of A, 14 is the Northing, and 6 is the value of the
line below spot height A.
Look and learn:
1. A cliff 2.
POPULATION DYNAMICS
A. 1. population dynamics 2. census 3. migration 4. 500 5. age-sex
B. 1.False. Regions with moderate climatic conditions are more densely populated than regions with
extreme climatic conditions.
2. False. The high population density of Macau is mainly due to immigration.
3. True
4. False. Overpopulation is caused by immigration.
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5. True
6.False. Population pyramids give information about the age structure and the sex ratio of any given
population.
C. 1. d
2. b
3. a
4. d
5. a
6. b
D. 1.Migration does not change the overall size of the world’s population because it is just the
movement of people from one part of the world to another. Neither does it add to the existing
population nor does it reduce the population.
2.Slums are a feature of many major cities in the world because there is a shortage of housing in
these cities as a result of overpopulation.
3.Infrastructure remains underdeveloped in underpopulated regions because the population is too
low to support its funding and maintenance.
4.The dependency ratio of a country tells the economists and government planners what
percentage of the population is dependent on the productive population. A high dependency
ratio would indicate more pressure on the working population and a low dependency ratio
would indicate that the working population can comfortably support the needs of the dependent
group. The dependency ratio helps the government decide the amount of resources that must be
allocated for education, pension and healthcare.
E. 1.The word ‘population’ refers to the total number of people living in a particular area at a given
point of time.
2.The population of a place, its size and composition, is constantly changing. The study of these
changes—how the population grows or declines, its changing composition and the factors
responsible for these changes—is known as population dynamics.
3.
Immigration
Emigration
The movement of people into a particular
place is called immigration.
The movement of people out of a particular
place is called emigration.
When many people immigrate, the population
of the place that they move to increases.
When many people emigrate, the population
of the place that they move out of decreases.
4.Underpopulation can be a result of many factors. • A sudden rise in death rate as a result
of natural catastrophes like earthquakes, droughts or epidemics can cause a place to become
underpopulated. • Lower birth rates due to changing socio-economic conditions, such as an
increase in nuclear and single-parent families and government policies that encourage smaller
families can result in underpopulation. • War and lack of employment opportunities can lead to
a high rate of emigration and result in underpopulation.
5.Place of low population density in Asia: Mongolia; Africa: Western Sahara; North America:
Greenland South America: Suriname, Falkland Islands; Europe: Iceland; Australia: Australia (any
three)
6.Overpopulation is a condition where the number of people living in an area exceeds the carrying
capacity of the land. In other words, the population density of the area increases to a point where
the supply of resources and infrastructure, like water, housing, food and transport, is not enough
to support the population.
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7.A low sex ratio means that the number of females is less when compared to the number of males
in a population. In India, harmful social practices like female infanticide and consistent neglect of
the girl child have kept the female population lower than the male population, resulting in a low
sex ratio.
8.The description of a given population on the basis of different characteristics, namely age
structure, sex ratio, occupation and literacy is known as population composition.
F. 1.Many factors influence the size of the population of a particular place. Some factors are
responsible for an increase in population, while others cause a drop in population.
Birth
rate: Birth rate is the number of live births per 1,000 people per year. Usually, a higher
birth rate leads to an increase in population, while a lower birth rate results in a decrease in
population.
Death
rate: Death rate is the number of deaths per 1,000 people per year. Other factors being
constant, when the death rate increases, the population decreases, and when the death rate
decreases, the population increases.
Migration:
Migration is the movement of people away from or into a place. It can be of two
kinds—immigration and emigration. When many people immigrate, the population of the place
that they move into increases. When many people emigrate, the population of the place that they
move out from decreases.
2.The human population increased steadily between the years 1400 and 1800—growing by around
600 million in 400 years. Then, from the year 1800, the population began to grow rapidly. It
doubled in just 100 years (from 1800 to 1900), and then increased by four times over the next 100
years. Thus, between 1900 and 2000, human population increased by almost 5000 million.
This
rapid and sudden increase in human population is called the Population Explosion. It was
a result of rising birth rates and falling death rates. The decline in death rates was a result of
improved medical care, better management of famines, floods and other natural disasters and
better living conditions.
3. There are many factors that determine the density and distribution of population.
Geographical
factors: Plains and plateaus have a higher population density than mountainous
regions. This is because places with flatter terrain are better suited for agriculture, and the
development of transport networks and industries. The rugged terrain of mountainous regions
makes cultivation and the development of roads, railways and industries difficult. For example, the
Indo-Gangetic Plain has a very high density of population, while the higher reaches of Himalayan
mountains have a low density of population.
Climate:
Regions with moderate climatic conditions are more densely populated than regions
with extreme climatic conditions. For example, the warm regions of Southeast Asia are some of
the most densely populated parts of the world, while the hot and arid Sahara Desert and the
freezing Polar Regions are among the least populated regions.
Availability
of resources: Areas rich in natural resources are thickly populated. For example, the
Ruhr region of Germany has rich deposits of coal and has become the centre of the iron and
steel industry in Germany. It is one of the largest industrial regions and also one of the densely
populated regions of the world.
Infrastructure:
Regions with well-developed facilities like healthcare, education, transport facilities
and housing are densely populated. Regions with good infrastructure also attract industries.
Industries, in turn, draw more people to the region as they provide ample opportunities for
employment.
5.Under population is a condition where there are not enough people living in a place to make full
use of the resources and technological advancements available there. Greenland, Australia and
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Canada are some of the underpopulated countries in the world. Rural areas also often tend to be
underpopulated.
Impact
of under population: Under population has both positive and negative effects.
Its positive effects include: • Ample employment opportunities • Enough space for
comfortable housing, transport and other infrastructure • Low levels of pollution and minimal
environmental degradation The negative effects are: • Without an adequate workforce,
resources are not used to their full potential. • Highly skilled workers do not find enough
opportunities for work. • There is usually a low demand for goods in underpopulated regions.
This acts as a deterrent to the growth of industries in those regions, as there is no market for
the goods. Hence, such regions often remain economically underdeveloped. • Infrastructure
also remains underdeveloped because the population is too low to support its funding and
maintenance.
6.One of the important characteristics of a population is its age-sex composition. This information
is presented in the form of a population pyramid, also called an age-sex pyramid. It reveals
information about the age structure and the sex ratio of any given population.
An
expansive population pyramid shows a population that has a high percentage of younger
age groups. It points to the prevalence of high birth rates. A constrictive population pyramid
shows a low percentage of younger age groups in a population. It indicates declining
birth rates. A stationary population pyramid shows an equal proportion of each group in a
population. It means that the population is relatively stable, with similar numbers of births and
deaths.
[Diagram: Population pyramid—India Population (2001)]
The
population pyramid—India Population (2001) shows that the female population of India
is lower than that of the male population across age-groups. It shows a low sex ratio. It is an
expansive population pyramid indicating that birth rates are high. We can see that the population
in the age groups 15–19, 20–24, 25–29, … 55–59, 60–64 is higher than the combined population
in the age groups 0–14 and the age-groups above 65 years. This means that the size of the
dependent population is lesser than the size of the productive (working) population.
7.Rural-urban composition studies the distribution of population between rural areas and urban
areas. Rural and urban populations vary in many social, economic and cultural ways. People
living in rural areas are generally more closely bound to the natural environment and to each
other. People living in cities and towns are usually better off financially than rural people. They
also have access to better medical and educational facilities. The rural-urban composition of a
population is an indicator of the economic development of a country. Usually, countries that have
a larger percentage of urban population are economically more developed than countries with
predominantly rural population. A rural area is one: • that is at a great distance from towns
and cities • where the population density is comparatively lower • where the settlements
are small (mostly villages) • where activities like agriculture, fishing and mining are the main
occupations • where the infrastructure, such as roads, bridges, concrete buildings and public
transport, is limited
An
urban area is one: • that includes (and surrounds) a city or town • that has a large
population and a high population density—that is, it has many people living close together in
a small place. In India, an area with a minimum population of 5,000 people, with a density of at
least 400 persons per sq. km, is considered to be urban. • where most people are involved
in occupations that are non-agricultural in nature, such as manufacturing, trade, transport and
banking • that has a well-developed infrastructure with large buildings, good roads, pavements,
improved systems of sanitation and well-connected systems of communication
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Look and learn
Dependency ratio: 56.5 approx.
Sex ratio: 952 approx.
MIGRATION
A. 1. push 2. Internal 3. irregular, illegal
4. remittances 5. human capital flight
B. 1. False. Early humans migrated mainly in search of food, and in response to climatic changes and
natural disasters.
2. False. Migrants who are forced to leave their country owing to threats posed to their lives and
freedom are known as refugees.
3. False. Remittances sent by emigrants help the economy of the parent country.
4. False. Immigration leads to a drop in the standard of living in the host country.
5. False. Countries that receive highly skilled migrants experience brain gain.
C. 1. b 2. b 3. a 4. a
D. 1. Tourism is the activity of travelling to a place for pleasure or recreation. Migration, on the other
hand, is the movement of people from their place of origin to another, with the intention of
settling down there temporarily or permanently. It is thus different from tourism.
2. Communal or racial conflicts and war pose a threat to the life, freedom or security of people,
which is why they are push factors for migration.
3. People migrate from urban to rural areas to return to their place of origin, to get away from urban
problems like pollution and lack of space and sometimes for economic reasons.
4. Employment opportunities increase in the parent country as a result of emigration as there are
fewer people competing for jobs.
5. In India, brain drain started around the 1950s when highly skilled people, who found themselves
stagnating because of inefficiency in organisations and lack of jobs and research facilities, began
to leave the country.
E. 1. Migration is the movement of people from their place of origin to another, with the intention of
settling down temporarily or permanently.
2. The earliest known human migration was that of early humans moving out of Africa, millions of
years ago.
3. Two advantages of immigration: • The knowledge and skills of highly skilled immigrants
contributes to the progress of the local economy. • Unskilled immigrants are often willing
to work for a lower pay than the local workforce. They are also willing to take up jobs that the
local people are unwilling to do. Two disadvantages of immigration: • There are fewer job
opportunities for the local workforce when employers choose the immigrant workers over
them. • When entire families immigrate, the pressure on the infrastructure of the host country
increases. This causes a fall in the standard of living and an increase in the cost of living in the
host country. • Money flows out of the economy of the host country as many immigrants
send their earnings to the parent country. • Differences in culture often give rise to conflicts.
Permanent immigrants may find it difficult to blend in. • Immigrants often get exploited and
treated unfairly. (any two)
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