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Why Does Population Growth Vary among Regions?

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Why Does Population Growth Vary among Regions?
Chapter 2 Lecture
The Cultural Landscape
Eleventh Edition
Population and
Health
Matthew Cartlidge
University of Nebraska-Lincoln
© 2014 Pearson Education, Inc.
Learning Outcomes
• 2.1.1: Describe regions where population is
clustered and where it is sparse.
• Identify the most populated regions.
• 2.1.2: Define three types of density used in
population geography.
• Analyze and describe contributing factors of
population concentrations.
© 2014 Pearson Education, Inc.
Key Issues
• Where is the world population distributed?
• Why is global population increasing?
• Why does population growth vary among
regions?
• Why do some regions face health threats?
© 2014 Pearson Education, Inc.
Learning Outcomes
• 2.3.1: Describe the four stages of the
demographic transition.
• 2.3.2: Summarize two approaches to
reducing birth rates.
• 2.3.3: Summarize Malthus’s argument
about the relationship between population
and resources.
• 2.3.4: Summarize the possible stage 5 of
the demographic transition.
© 2014 Pearson Education, Inc.
Learning Outcomes
• 2.4.1: Summarize the four stages of the
epidemiologic transition.
• 2.4.2: Summarize the reasons for a
possible stage 5 of the epidemiologic
transition.
• 2.4.3: Understand reasons for variations in
health care.
© 2014 Pearson Education, Inc.
Where Is the World’s Population Distributed?
• Population Concentrations
– 2/3 of the world’s inhabitants are clustered in
four regions.
•
•
•
•
East Asia
South Asia
Southeast Asia
Europe
– Site and Situation of Population Clusters
• Low-lying areas with fertile soil and temperate
climate
• Near an ocean or near a river with easy access to
an ocean.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Where Is the World’s Population Distributed?
• Sparsely Populated Regions
– Humans avoid clustering in certain physical
environments.
•
•
•
•
Dry Lands
Wet Lands
Cold Lands
High Lands
– Places considered too harsh for occupancy
have diminished over time.
• Places of permanent human settlement are termed
the ecumene.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Where Is the World’s Population Distributed?
•
Population Density
– Density can be computed in up to three ways for a place.
1. Arithmetic Density
– Total number of objects in an area
– Computation: Divide the population by the land area
2. Physiological Density
– Number of people supported by a unit area of arable land
– Computation: Divide the population by the arable land area
3. Agricultural Density
– Ratio of the number of farmers to amount of arable land
– Computation: Divide the population of farmers by the arable
land area
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Is Global Population Increasing?
•
Components of Population Growth
– Geographers measure population change in a country or the world as a
whole by using three measures:
• Crude Birth Rate (CBR) – total number of live birth in a year for every
1,000 people alive in society.
• Crude Death Rate (CDR) – total number of deaths in a year for every
1,000 people alive in society.
• Natural Increase Rate (NIR) – percentage by which a population
grows in a year.
– Computation: CBR – CDR = NIR
» Remember NIR is a percentage ( n per 100, while CBR and
CDR are expressed as n per 1,000)
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Is Global Population Increasing?
•
Components of Population Growth
– Natural Increase
• About 82 million people are added to the population of the world
annually.
• Rate of natural increase affects the doubling time– number of years
needed to double the population, assuming a constant rate of natural
increase.
– Twenty-First Century Rate (1.2 percent): 54 years
» Global population in 2100 would reach 24 billion.
– 1963 (2.2): 35 years
» Global population in 2010 would have been 10 billion instead
of nearly 7 billion.
• More than 95 percent of the natural increase is clustered in developing
countries.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Is Global Population Increasing?
• Components of Population Growth
– Fertility
• Total Fertility Rate (TFR)
– Measure also used by geographers to measure number of
births in a society.
– Defined as the average number of children a woman will
have throughout her childbearing years (15–49)
– TFR for world is 2.5.
– TFR exceeds 5 in sub-Saharan Africa, while 2 or less in
nearly all European countries.
© 2014 Pearson Education, Inc.
Why Is Global Population Increasing?
• Components of Population Growth
– Mortality
• Infant Mortality Rate (IMR)
– Measure used by geographers to better understand death
rates in a society
– Defined as the annual number of deaths of infants under
one year of age, compared with total live births
– Usually expressed per 1,000 births rather than a percentage
– IMR is 5 in developed countries and 80 in sub-Saharan
Africa.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Is Global Population Increasing?
• Summary of Spatial Patterns
– Developed Countries
• Lower rates of…
–
–
–
–
Natural increase
Crude birth
Total fertility
Infant mortality
– Developing Countries
• Higher rates of…
–
–
–
–
© 2014 Pearson Education, Inc.
Natural increase
Crude birth
Total fertility
Infant mortality
© 2014 Pearson Education, Inc.
Why Is Global Population Increasing?
• Population Structure
– A special bar graph known as a population
pyramid can visually display a country’s
distinctive population structure.
• X-axis
– Percent male displayed to the left of zero
– Percent female displayed to the right of zero
• Y-axis
– Age cohorts typically grouped in 5-year intervals
– Youngest displayed at bottom and oldest at top
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Is Global Population Increasing?
• Population Structure
– Dependency Ratio
• Defined as the number of people who are too
young or too old to work, compared to the number
of people in their productive years.
– People aged 0 to 14 and over 65 years old are
considered dependents.
– Larger dependency ratios imply greater financial burden
on the working class.
» 85 percent in sub-Saharan Africa, while 47 percent in
Europe.
© 2014 Pearson Education, Inc.
Why Is Global Population Increasing?
• Population Structure
– Sex Ratio
• Defined as the number of males per 100 females
in the population
– Developed countries have more females than males,
because they tend to live 7 years longer.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Review:
3 Densities Review:
Arithmetic Density: # people/unit area of land
*large density=more people in more places
Physiological Density: #people supported by /unit area of arable land
large density=more pressure to produce food from the land for people)
Agricultural Density: # farmers/ unit area of arable land
*large density= requires more work to produce food from the land for
people
*Developed countries have low agricultural densities. Why?
*Why would geographers compare physiological and agricultural densities of various countries?
*Why would geographers compare physiological and arithmetic densities of various countries?
© 2014 Pearson Education, Inc.
Review:
Example: Egypt vs. Netherlands vs. U.S.
 Egypt has both a large agricultural and physiological density.
 The Netherlands has a large physiological, but low agricultural density.
 Egypt has a low arithmetic density.
 What can geographers tell about the difference between Egypt and the
Netherlands?
 Why does Egypt have high agricultural and physiological densities, but a low
arithmetic density? How might it create a problem?
 Do you think the U.S. has high or low densities in arithmetic, physiological, and
agricultural? Why?
© 2014 Pearson Education, Inc.
Current Events Assignment:
 Brief summary of article – 5-7 sentences (not more nor less)
 All answers should be written in complete sentences.
 For additional comments, include your opinion on the issue and explain what you learned. There is no limit
here.
 Each time a current event assignment is due, I will choose 3 random students to present their article.
 Be sure to have a clear understanding and enough information to explain to the class.
 Presentations should be at least 2 minutes (that’s a longer time than it sounds).
 Suggested websites include:
BBCNews.com
CNNStudentNews.com
PBR.org
Dailymail.co.uk
© 2014 Pearson Education, Inc.
Key Issue 1-2 Check up:
1.
2.
What type of density is also known as population density? (it’s one of the 3 types)
List 3 different rates of population growth geographers use to measure the population of a
country or the world as a whole.
3. What is the difference between a population’s structure vs. a population’s growth rate? Give
an example of each.
4. What type of information does a population pyramid display?
5. Developed countries have lower rates of: (4 answers)
6. Developing countries have higher rates of: (4 answers)
7. Developing countries have a lower rate of
than developed countries.
8. What is the difference between physiological density and agricultural density?
9. As the natural increase rate increases, the doubling time of that country
.
10. How is the natural increase rate computed? (what’s the formula?)
© 2014 Pearson Education, Inc.
Key Issue 1-2 Check up:
1.
2.
3.
Arithmetic
Crude birth rate, Crude death rate, Natural Increase Rate
Structure- what type of people in the population Ex: Dependency ratio, sex ratio
Growth –how the population increases Ex: Crude birth rate, total fertility rate, infant mortality
4. Amount of males and females in a population shown by age in 5 year increments
5. Developed countries have lower rates of:
a. natural increase
b. crude birth
c. infant mortality
d. total fertility
6. Developing countries have higher rates of: same answer as #5
7. Crude death
8. Physiological = # people/arable land; Agricultural= #farmers/arable land
9. Decreases
10. CBR-CDR=NIR
© 2014 Pearson Education, Inc.
Bell Ringer: September 24, 2015
 Take out your completed Key Issue 3 Notes
• Today’s Outcomes:
 Describe the four stages of the demographic transition model.
 Summarize Malthus’s prediction and the possible Stage 5 of the
demographic transition model.
 Evaluate specific country’s population growth rates and the policies,
which are the causes.
 Debate for or against various policies put into place to solve
population problems.
Essential Question: How can the demographic transition model be
used to analyze future declining population and/or overpopulation
problems?
© 2014 Pearson Education, Inc.
Why Does Population Growth Vary among
Regions?
• The Demographic Transition
– It is a model consisting of four stages that
helps to explain the rising and falling of
natural increase over time in a country.
– Historically, no country has ever reverted
back to a previous stage.
• Thus, the model can be thought to have a
beginning, middle, and an end.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Does Population Growth Vary among
Regions?
• The Demographic Transition
– Stage 1: Low Growth
• Marked by very high birth and death rates.
– No long-term natural increase
– No country presently is in Stage 1
– Stage 2: High Growth
• Marked by rapidly declining death rates and very
high birth rates
– High natural increase
– Europe and North America entered stage 2, as a result of the
industrial revolution (~1750).
– Africa, Asia, and Latin America entered stage 2 around 1950,
as a result of medical revolution-improved medical care.
© 2014 Pearson Education, Inc.
Why Does Population Growth Vary among
Regions?
• The Demographic Transition
– Stage 3: Moderate Growth
• Marked by rapid decline in birth rates and steady
decline in death rates
– Natural increase is moderate.
» Gap between CBR and CDR is narrower in stage 3
countries than stage 2 countries.
• Population grows, because CBR is still greater
than CDR.
• Most European countries and North America
transitioned to stage 3, during first half of twentieth
century.
© 2014 Pearson Education, Inc.
Why Does Population Growth Vary among
Regions?
• The Demographic Transition
– Stage 4: Low Growth
• Marked by very low birth and death rates
– No long-term natural increase and possibly a decrease
• Country reaches stage 4 when population gains by
CBR are diminished by losses because of CDR.
– Condition known as zero population growth (ZPG)
» Demographers more precisely define ZPG as the
TFR that produces no population change.
• Population change results from immigration.
© 2014 Pearson Education, Inc.
Why Does Population Growth Vary among
Regions?
• Declining Birth Rates
– Two Successful Strategies for Lowering Birth
Rates
1. Improving Education and Health Care
– Emphasizes improving local economic conditions so that
increased wealth is allocated to education and health
programs seeking to lower birth rates.
2. Contraception
– More immediate results reaped than previous approach
– Met with greater resistance, because it goes against
cultural or religious beliefs of some.
» Roman Catholics, fundamentalist Protestants,
Muslims, and Hindus.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Does Population Growth Vary among
Regions?
• Malthus on Overpopulation
– He claimed the population was growing faster
than the increase in food supply.
– Malthus’s Critics
• Many geographers consider his beliefs too
pessimistic.
– Malthus’s theory based on idea that world’s supply of
resources is fixed rather than expanding.
• Many disagree that population increase is not a
problem.
– Larger populations could stimulate economic growth, and
therefore, production of more food.
© 2014 Pearson Education, Inc.
Why Does Population Growth Vary among
Regions?
• Malthus on Overpopulation
– Theory and Reality
• Food production has increased over last 50 years
faster than Malthus predicted.
• His model predicted world population to quadruple
over the course of 50 years.
– Not even in India has population growth outpaced food
production.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Does Population Growth Vary among
Regions?
• Population Futures
– Demographic Transition Possible Stage 5:
Decline
• Characterized by…
– Very low CBR
– Increasing CDR
» More elderly people than young persons
– Negative NIR
– Over time, few young women in child-bearing years
» Contributing to ever falling CBR
• Several European countries already have negative
NIR.
– Russia is most notable hosting a negative NIR for 50 years.
© 2014 Pearson Education, Inc.
Why Do Some Regions Face Health
Threats?
• Epidemiologic Transition
– Medical researches have identified an
epidemiologic transition that focuses on
distinct health threats in each stage of the
demographic transition.
– Stage 1: Pestilence and Famine (High CDR)
• Principal cause of death: infectious and parasitic
diseases
– Ex. black plague (bubonic plague)
© 2014 Pearson Education, Inc.
Why Do Some Regions Face Health
Threats?
• Epidemiologic Transition
– Stage 2: Receding Pandemic (Rapidly
Declining CDR)
• Pandemic is a disease that occurs over a wide
geographic area and affects a very high proportion
of the population.
• Factors that reduced spread of disease, during the
industrial revolution
– Improved sanitation
– Improved nutrition
– Improved medicine
• Famous cholera pandemic in London in mid
nineteenth century.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Do Some Regions Face Health
Threats?
• Epidemiologic Transition
– Stage 3: Degenerative Diseases (Moderately
Declining CDR)
• Characterized by…
– Decrease in deaths from infectious diseases.
– Increase in chronic disorders associated with aging.
» Cardiovascular diseases
» Cancer
– Stage 4: Delayed Degenerative Diseases
(Low but Increasing CDR)
• Characterized by…
– Deaths caused by cardiovascular diseases and cancer delayed
because of modern medicine treatments.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Do Some Regions Face Health
Threats?
• Infectious Diseases
– Reasons for Possible Stage 5
• Evolution
– Infectious disease microbes evolve and establish a resistance to
drugs and insecticides.
– Antibiotics and genetic engineering contributes to the emergence of
new strains of viruses and bacteria.
• Poverty
– Infectious diseases are more prevalent in poor areas because of
presence of unsanitary conditions and inability to afford drugs
needed for treatment.
• Increased Connections
– Advancements in modes of transportation, especially air travel,
makes it easier for an individual infected in one country to be in
another country before exhibiting symptoms.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Why Do Some Regions Face Health
Threats?
• Health Care
– Health conditions vary around the world,
primarily, because countries possess different
resources to care for people who are sick.
• Expenditures on Health Care
– More than 15 percent of total government expenditures in
Europe and North America.
– Less than 5 percent in sub-Saharan Africa and South Asia.
© 2014 Pearson Education, Inc.
Why Do Some Regions Face Health
Threats?
• Health Care
– Health Care Systems
• Developed Countries
– Public service available at little or no cost.
– Government pays more than 70 percent of health-care
costs in most European countries, and private
individuals pay about 30 percent of the expense.
• Developing Countries
– Private individuals must pay more than half of the cost of
health care.
» U.S. is an exception to these generalizations, because private
individuals are required to pay about 55 percent of health care
costs making it more closely resemble a developing country, in
regards to health care.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
© 2014 Pearson Education, Inc.
Summary
• Global population is concentrated in a few
places that are not too wet, too dry, too
cold, or too mountainous.
• Nearly all NIR is concentrated in
developing countries.
• Developed countries have a stable
population, if not slightly declining.
• Population growth varies among regions,
because not all countries are in the same
stage of the demographic transition model.
© 2014 Pearson Education, Inc.
Summary
• Intimately connected to the demographic
transition model is the epidemiologic
transition model that helps to explain why
different regions face varying health
threats.
© 2014 Pearson Education, Inc.
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