GLOBAL
POPULATION GROWTH
Ÿ 1830 the world’s population
reached ONE BILLION
Ÿ 1930, just 100 years later the
population reached 2 billion.
Ÿ 1960 it reached 3 billion
Ÿ 15 more years later in 1975,
it climbed to 4 billion.
Ÿ 12 years later in 1987,
it crossed the 5 billion mark.
Ÿ 12 years later in 1999
the world’s reached 6 billion
Ÿ By 2029, the world’s population is
estimated to be 10.4 billion
DISTRIBUTION
OF WORLD’S POPULATION:
1. East
Asia: Approximately one-fourth of the
world's population lives in the East Asia region comprising eastern parts of
China, Japan, the Korean Peninsula and the island of Taiwan. Five-sixths of the
people in this region live in China.
2. South
Asia has
the second largest concentration of people. The region comprises India, Pakistan,
Bangladesh, and Sri Lanka. More than 20% 0f the world's population lives in
South Asia and India, the world's second most populous country contains more
than three-fourths of the people in this region.
3.
South-East Asia: A third Asian population cluster, and the world's fourth largest
comprise series of islands that lie between Pacific and Indian Oceans. The
largest concentration is on the island of Java (Indonesia) inhabited by more
than 100 million people. Indonesia consists of more than 13,677 islands and is
the fourth most populous country in the world. Included in this region is
Philippines.
4. Europe:
The world's third largest
population cluster encompasses about two dozen countries that occupy much of
Europe from the United Kingdom to western Russia. Approximately 15% of the
world's people live in this cluster.
5. North
America: The largest concentration
of people in the Western Hemisphere is in the Northeastern United States and
South Eastern Canada. Approximately 150 million people live in this region and
like the Europeans, most Americans are urban dwellers and fewer than 5% are
farmers.
Sparsely
Populated Areas: Harsh environments such as
deserts and very cold tundra or hot and wet tropical regions are sparsely
populated. The largest desert region of the world extends from North Africa to
Southwest and Central Asia and includes Sahara, Arabian, Thar, Makan and Gobi
deserts. The largest desert region in the Southern Hemisphere is found in
Australia.
THEORIES
ABOUT POPULATION GROWTH:
1. Malthusian Theory: Population growth and
Food production: Thomas Malthus (1798)
2. Population as an Asset: Esther Boserup (1965, 1981) and others.
3. Poverty, (not Population growth) is the
Problem: by
Karl Marx,
THE
DEMOGRAPHIC TRANSITION THEORY
Demographic
transition refers to changes in population growth that occur when a country
moves from high birth and death rates to low birth and death rates as the
country embarks upon industrialization. The changes take place in 4 stages of a
nations development:
Stage
1: Pre-Industrial Stage: the country is in the pre-industrial state, high birth and high but fluctuating death rates
death rates are experienced.
Stage
II: Early Industrial Stage: Death rates fall because of improving economic and social conditions
but birth rates remain high.
Stage
III: Industrial Stage: Birth rates begin to fall due to industrial development, education and
jobs. Death rates also falls due to advanced medical practices, research and
improved living conditions.
Stage
IV: Post-Industrial Stage: Zero population growth, death rates falls drastically and birth rate
is low but fluctuates.
Why
Cant Developing Countries today take advantage of the Demographic Transition
1. Lack of trained personnel for industrial
development.
2. Lack of an essential energy base and or a
combination of factors
3.
Rapid population growths and the
resulting cycle of poverty prevent savings and investment.
4. Lack of financial resources.
HUMAN
POPULATION GROWTH: (factors)
1. A broader worldwide food base developed from
improvements in trade and global transportation.
2. Humanity developed resistance to several
diseases.
3. Better medical technology and research led
to an increase in survivorship and a drop in child and infant mortality.
4. Improvements in general living conditions
mean longer life span for many people.
5. The change from pre-reproductive to
post-reproductive death with development in medical science has helped people
to give birth before they die.
POPULATION
INCREASE:
Natural
Increase: is a
measure of population growth that examines the difference between births
(fertility) and deaths (mortality) in a country for a given year.
Ÿ The number of persons born
per 1,000 individuals in population for a given year is the Crude Birth Rate
Ÿ The number of persons per
1000 individuals in a population who die in a particular year is the Crude
Death Rate.
FERTILITY RATE:
Total Fertility Rate is a measure of the average
number of children a woman can have during the reproductive years of her life
(15 - 49 years). It is an average figure that reveals the number of children
per family. In 1990, the total fertility rate for American women was 2.0, after
declining from about 3.3 in 1950 to 1.8 in 1985. It is currently less than 2.
On the global scale, the total fertility rate was 3.0
in 1996. It was higher (3.4) in developing countries and lower (1.6)
in developed nations. Africa in 1996 had a fertility rate of 5.7, S.E Asia has
3.6 and the Caribbean 3.1
How has fertility rates changed in the United
States?
United States total population grew from 76 million
in 1900, to 265 million in 1996 - a 3.5 fold increase even though the total
fertility rate has oscillated widely. In 1957, the peak of the post World War
II baby boom, the Total Fertility Rate reached 3.7 children per woman. Since
then, the rate has declined to about 2.0 in 1990 and has remained below
replacement level since 1972. The drop in fertility rate has not led to a
significant decline in the growth of population in the US compared to European
nations. This is due to a number of reasons:
1. Large number of wealthy baby-boom women who are still in their
giving birth to children.
2. An increase in the number of teenage pregnancies.
3. High fertility rates for women (minorities) in racial groups other
than Caucasian women.
4. High levels of legal and illegal immigration (accounts for 40% of
current US population growth).
Reasons
for Disparities in Total Fertility Rates Between Nations
1. The society’s view of children as family
income earners or part of the population undergoing training and receiving
education.
2. The absence of private of public Old Age
Social Security payments encourages parents in poor countries to bring forth
children who will take care of them in their old age.
3. Educational and Career Opportunities,
particularly for women, can cause drop in population growth.
4. Status of Women in Society. When several
women move from the home to obtain jobs, population growth declines in the
country.
5. Some religions such as Muslim encourage men
to have more wives and several children while others such as the Roman Catholic
does not support abortion and rather teaches celibacy, abstention and one man
one wife.
6. The availability of safe family planning and
birth control services helps prevent unwanted pregnancies.
7.
Infant Mortality: Frequent deaths to
infants have been a motivation factor to families to experiment with more childbirth
so a few could live.
8.
Average level of affluence and
education in the society
9. Cost of raising and educating children in
the particular society.
10. Average age at Marriage, particularly for
women can influence population growth in a given society.
AGE
STRUCTURE OF A POPULATION
The
age structure is the number of individuals occurring in each age class within a
population. The diagram displaying the age structure of a population is often
called a Population Pyramid. A pyramid depicts the pattern of growth in the
population of a country. To construct the population pyramid for a country, follow the steps
below:
1. Classify the population
first (1) by sex into males and females and then (2) into age groups of 5-year
intervals (0-4. 5-9, 10-14 etc.) called cohorts. In a census data, look for
tables that show the characteristics described above.
2. Compute percentages of the actual number of people in each
five-year category for both males and females (example, (a) total of females
aged 0-4 / total population * 100 = ---%. (b) Total males aged 0-4 / total
population * 100 = --- %). Do the same for all cohorts
3. Graph the percentages of 5-year age groups for males and females
(on x-axis) against the age groups (0-4, 5-9, 10-14, etc on y-axis) .
4. On the graph, percentage for
Males is shown on the Left of the middle axis and the percentage of Females
shown on the Right.
5. The pre-reproductive age is
usually between 0-14, Reproductive age 15-44 and
post-reproductive age 45-85+
i)
Rapidly growing populations have broad based population pyramids. This
is characteristic of poor developing countries of Latin America, Africa and
Asia.
ii)
Stable populations have pyramids that are elongated with a narrow base.
Populations of several European countries including France, Netherlands and the
Scandinavian countries, and also USA and Canada depict have stable populations.
iii)
Declining Populations have pyramids with a very small base and slightly
large tops. Austria, Germany (East and West), Japan and other developed nations
have declining populations. There tend to be a large proportion of senior
citizens in the population.
Relevance of Age-Structure Diagram
1. It indicates the occupation
structure of the population.
2. It provides information
about both sexes in the population. A proportion of more women below the age of
15 years in the population provide an indication of a possible high future
growth rate.
3. Provide clues to present and the future trends in the growth rates
of the population.
4. It provides information
about the impacts that past events such as wars and economic booms had on the
general population. The impacts are registered as deaths and births.
THE DEPENDENCY RATIO:
In terms of economics, the
population of a country can be divided into the following categories:
a)
0-18
years = Economically dependent group
b)
19
– 65 = The Labor Force; comprising the
working people that pays income tax to run the country.
c)
65+
years = Senior citizens; also economically dependent group
The dependency ratio for a country’s population
is calculated as:
Total Populations (0 - 18 +
65+ yrs.) 100
Total Population 19 – 65
year olds X 1
ADDRESSING
THE POPULATION PROBLEM
INDIRECT
METHODS:
Improving
the Lives of the People to Decrease Population Growth.
a). Increasing food production
b). Food Aid.
a)
Undercuts domestically produced food leading to losses to local farmers,
and lower agricultural outputs.
b)
Introduces the population to diets other than what is locally available
thereby necessitating imports.
c). Social and Economic Development.
DIRECT
METHODS TO CONTROL POPULATION GROWTH
Reducing
Fertility to Bring down Population Growth
a) Family
Planning Methods
b)
Demographic Transition Theory
c)
Abortion
d)
Abstinence
e)
One Family One Child Policy