Human Population
• Population is a group of individuals of same species that live in the
same area at a particular time.
• The branch of population dealing with the scientific study of human
population is called demography.
Census
• Census is an official count of the people of a country, state or district
with statistic such as age, sex, education, employment etc.
• It is an extensive work & takes on every 10 years. Census help in
planning the developmental programs.
Demography
• Scientific study of human population is known as demography.
• The persons who study the nature of human population change are
called demographers.
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Demography deals with five demographic processes namely fertility,
mortality, marriage, migration and social mobility.
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These five processes continuously function within a population
determining its size, composition and distribution.
Demographic cycle
• Every nation has to pass through the following five stages of the
demographic cycle.
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First stage: both birth and death rate are extremely high.
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Second stage: The death rate tends to fall but birth rate is
stagnant. -
Third stage: The death rate still keeps on falling and the birth rate
is also tending to fall. -
Fourth stage: Both death rate and birth rate are low.
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Fifth stage: The birth rate becomes lower than the death rate. This
stage lasts for a short period of time. -
The rate of increase in natural population varies from one global area
to another.• Growth rate is much lower in the developed countries than in the
under-developed or developing countries. -
Malthus theory of human population growth
• Malthus, British political economist, put forward a theory of human
population growth in 1978. He state that:
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Population multiplies in geometrical ratio where as food resources
multiplies in arithmetic ratio. -
Faster growth of population than that of its requirements creates
an imbalance between the two -
When the imbalance reaches to a certain limit malnutrition,
epidemic diseases, war & environmental factors such as earthquake,
flood, pollution etc reduce the population to a size the available
resources can support.The factors that control the population size were called as positive
checks by Malthus.
Definition of various demographic
terms
• Birth rate(Natality): It refers to the number of offspring produced
per thousand unit of population per year.• Death rate(Mortality): It refers to the number of death per thousand
of individual population per year.• Sex ratio: It is the ratio of male & female in a given population.
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