Download The Human Population Part 2 Demographic Transition 11/25/2014

11/25/2014
The Human Population Part 2
November 25, 2014
Mr. Alvarez
Demographic Transition
Theory of Demographic Transition- as a country
moves from a subsistence economy to
industrialization and increased affluence, it
undergoes a predictable shift in population growth
The Four Phases
1. Phase 1- the beginning of the transition, the
country experiences slow growth or no
growth
2. Phase 2- Country experiences rapid growth
– Countries in Africa as well as China and India
3. Phase 3- Population Stabilization
– United States, Canada, Australia
4. Phase 4- Population Declines
– Many European Nations
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Phase 1
• Phase One- Slow population growth because
there are high birth rates and high death rates
which offset each other.
– CBR = CDR
– Low Life Expectancy
– High Infant Mortality
‒ Subsidence Economy
• Disease
• Lack of health care
• Poor sanitation
•
•
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Most people are
farmers
Children are assets
No Social Security
Phase 2
 Phase Two- Rapid population growth
because birth rates remain high but death
rates decline due to better sanitation, clean
drinking water, increased access to food and
goods, and access to health care.
 Infant mortality rates and CDR decrease
 Takes at least one generation to realize this
 Education systems not yet in place
 Not many birth control measures
Phase 3
 Phase Three- Stable population growth as the
economy and educational system improves and
people have fewer children.
Having many children may be a financial burden
More time spent pursuing education
Availability of Birth Control
Cultural, societal and religious norms may also play a role
Birth and death rates decrease
System returns to steady state
Population size does not change very quickly
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Phase 4
Phase Four-Declining population growth
because the relatively high level of affluence
and economic develop encourage women to
delay having children.
Fewer young people and higher proportion of
elderly
Elderly become a burden due to pension
programs and Social Security
Possible shortage of healthcare workers
Governments may encourage immigration
Family Planning
 Family planning- the regulation of the
number or spacing of offspring through the
use of birth control.
The 12 Most Populous Countries in the
World
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Population Growth Past and Future
Ecological Footprints
Affluence- having lots of wealth such as money,
goods, or property
The IPAT Equation
• To estimate the impact of human lifestyles on
Earth we can use the IPAT equation:
• Impact= Population X Affluence X Technology
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Urban Growth
The 20 Largest Urban Areas in the World
The Impact of Affluence
 Gross domestic product (GDP)- the value of
all products and services produced in a year
in that country.
 GDP is made up of consumer spending,
investments, government spending, and exports
minus imports.
 A countries GDP often correlates with its
pollution levels.
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The Millennium Ecosystem
Assessment (2005)
• Ecosystem sustainability will be threatened if the
human population continues along its current
path of resource consumption around the globe
• The continued alterations to ecosystems that
have improved human well-being (greater access
to food, clean water, suitable housing) will also
exacerbate poverty for some populations
• If we establish sustainable practices, we may be
able to improve the standard of living for a large
number of people
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