Transcript Population

Population
In the last 200 years the population of our
planet has grown exponentially, at a rate of
1.9% per year. If it continued at this rate,
with the population doubling every 40 years,
by 2600 we would all be standing literally
shoulder to shoulder.
-- Professor Stephen Hawking
Population Geography
 Distribution of World Population
 Population Statistics
 Population Pyramids
 Demographic Transition Theory
 Population Control
 Overpopulation (Malthus and Neo-Malthusians)
Population Density
 Arithmetic Density Total population/Total Land area
 U.S. = 76/mi2; NYC=1,000,000/mi2; Australia = 7/mi2
 Physiological Density Total population/ Total Farmable land
 95% of Egyptians live near the Nile river
 Agricultural Density Total farmers/Total farmable land
 High-most people are farmers Low-not many farmers needed
Country
Arithmetic
Physiologica
l
Agricultural
% of farmers
% of Arable
land
Canada
3
65
1
2
0.5
US
32
175
2
2
1.7
The
Netherlands
400
1748
23
3
0.01
Egypt
80
2296
251
31
0.03
World and Country Population Totals
Distribution and Structure: 3/4 of people live on 5% of earth's
surface!
Total: 7 billion on planet as of Oct. 31, 2011
http://www.worldometers.info/world-population/
Five most populous regions and countries
REGION
 East Asia
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POPULATION
1.5 billion
South Asia 1.2 billion
Europe
750 million
SE Asia
500 million
East N. Am.120 million
COUNTRY
POPULATION
China
India
U.S.
Indonesia
Brazil
1.387 billion
1.254 billion
320 million
250 million
200 million
Population Statistics
Crude Birth Rate
CBR
Total number of live births per year per 1,000 of the
population
Crude Death Rate
CDR
Total number of deaths per year per 1,000 of the
population
Natural Increase
Rate
NIR
The percentage in which a population grows or shrinks
per year
Total fertility Rate
TFR
Total number of children a woman will have during her
lifetime
Infant Mortality
Rate
IMR
The number of infant deaths (under 1 year old) per
1,000 live births per year
NIR Formula
CBR – CDR=NIR
Example: 20 (CBR)-5 (CDR)=15 per
1,000 or
1.5%
ALWAYS EXPRESSED AS A PERCENT!!!
Rates of Natural Increase
Total Fertility Rate TFR - the average
number of children a women will have in
her childbearing years. This rate varies
from just over 1 (Japan, Italy) to around 7
(Niger, Mali). The U.S. rate is 2.
Palestinian
Territories
1975-1980
7.39
1980-1985
7.00
1985-1990
6.43
1990-1995
6.46
1995-2000
5.99
2000-2005
5.57
Total
fertility
rate
U.K.
2.1 is generally regarded as the
replacement rate (the rate at
which a population neither grows
nor shrinks) in the developed
world. In less developed countries
this rate should be higher to
account for so many children not
reaching childbearing age.
Fertility
Rate
1975-1980
1.72
1980-1985
1.80
1985-1990
1.81
1990-1995
1.78
1995-2000
1.70
2000-2005
1.66
Africa
Fertility
Rate
1975-1980
6.60
1980-1985
6.45
1985-1990
6.11
1990-1995
5.67
1995-2000
5.26
2000-2005
4.97
Infant Mortality Rate IMR – the number of deaths of children under the age
of one per thousand live births. The rate ranges from as low as 3 (Singapore,
Iceland) to as much as 150 (Sierra Leone, Afghanistan). The U.S. rate is just over
6. High infant mortality tends to result in higher fertility rates as families seek
“insurance” for the loss of children.
Family Planning Programs
 One family/one child policies
 Sterilization
 Increased taxes
 Loss of social status
 Termination healthcare/food coupons
 Free birth control
 Increased literacy and education to stop
unwanted births
Demographic Transition Model
 Developed in 1929 by American demographer Warren
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Thompson
Using demography statistics, level of industrialism and
economic wealth, each country is placed into stages
Most countries are currently in Stage 3 or higher
The exception would be Sub Saharan, parts of the Middle
East and Asia
The model is growing outdated as countries reach the end of
stage 4
Demographic Transition Model
DTM Stages
 Stage one (preindustrial/pre-agricultural)
 Crude birth/death rate high
 Several spikes and drops in CBR/CDR
 Stage two (improved agriculture and medicine)
 Lower death rates
 Infant mortality rate falls
 Natural increase very high
 Stage three (Social change)
 Indicative of richer developed countries
 Higher standards of living/education
 Crude birth rate finally falls
 Stage four
 Crude birth/death rates low
 Population stable
 Populations aging
DTM Possible Stage 5
 Most of the highly developed countries are exhausting the 4th
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stage
Demographers are now starting to theorize a 5th and possible 6th
stage of Thompson’s model
Very low CBR, CDR and a total population decline in a country
Replacement rate is not being met and the country is declining in
population (does not account for migration)
These countries are highly industrialized, high levels of education
and equality
Any population increase would be due to immigration and not
citizens having kids
3 reasons for stage changes
Agricultural
Revolution
Occurred around 8000
B.C.
Humans began to farm
and establish ecumene
Famine, droughts and
wars kept CBR and CDR
unstable
Industrial
Revolution
Medical
Revolution
Occurred in 1750
 Late 20th century
Improvement in
industrial technology
Helped LDCs enter
stage 2 (Like South
America)
Increased wealth,
sanitary conditions,
agricultural production
Increased CBR and
decreased CDR
Led to higher CBR and
lower CDR
Improved life
expectancy
Western Europe
Immunizations,
antibiotics
Why a country changes from stage 2 to stage 3
Technology
•Medical technology
allows for CBR and
CDR to decrease
•Access to medicine
•Access to sex
education
•Access to birth
control
•Infant mortality rate
declines
•More doctors
Economic
Social
• People live in urban
areas with less room
for large houses
•People work in offices
or factories where kids
are not allowed
•Kids are not
economics assets to
their parents (they cost
more money)
•No child labor in
urban cities
•Women enter labor
force therefore less
time for kids
•Access to birth
control methods to
stop unwanted kids
•Increased wealth and
leisure time (no time
for kids)
•No need or pressure
to reproduce
•It is acceptable not to
have kids
Cape Verde
Chile
Denmark
•Stage 2 in 1950
•Remained in stage 2
currently due to famine
and fluctuation between
CBR/CDR
•As with other African
and Latin America
countries…only entered
stage 2 because of the
medical revolution
•Entered stage 2 because
of medical revolution
oMoved to stage 3
because of government
family planning policies in
1966. Reduced incomes
and high employment
postponed marriage and
childbearing
•Will not move into stage
4 because Chile has
reversed policy and most
Chileans are Roman
Catholic who do not
believe in artificial birth
control methods
•Entered stage 4 because
CBR is approaching ZPG
and social revolution
•Population is in decline
•CBR is declining while
CDR is rising
•CDR will continue to
rise unless a new
medical revolution
takes place
•CBR will only increase
through immigration
Weakness of the DTM
 It is only a model
 Becoming increasingly outdated as countries reach stage
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4
New geographical studies suggest that fertility decline
doesn’t have to be connected to increased wealth
As well as an increase in fertility in highly wealthy
countries
The model does not account for immigration in each
country
Immigrants tend to have higher TFR than citizens
Population Pyramids
 Bar graph that displays demography data
 Pyramids show
 Age -Young vs Old
 Gender- Male vs Female
 Dependency Ratio- Number of population under 15 and over 65
• Stage 2 countries have a dependency ratio of 1:1
•
10:1 for younger dependants
• Stage 4 countries have a dependency ratio of 2:1
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Elderly and young are roughly equal. More than ¼ government expenditures
are on the elderly in stage 3 and 4 countries
 Women outnumber men in most MDCs
 Countries with high immigration have more males
 Retirement communities have more women than men
 Population Pyramids are effected by ethnic compositions
Italy, 2000
AGE
4
80+ y rs.
75-79 y rs.
3
70-74 y rs.
65-69 y rs.
Males(% )
Females(% )
60-64 y rs.
55-59 y rs.
50-54 y rs.
45-49 y rs.
40-44 y rs.
35-39 y rs.
5
2
30-34 y rs.
25-29 y rs
20-24 y rs
15-19 y rs.
10-14 y rs.
1
5-9 y rs.
0-4 y rs.
10
8
6
4
2
0
PERCENT
2
4
6
8
10
Analysis of Italy’s
Population Pyramid
 1. Decline in Birth Rate
 2. Baby Boom
 3. Fewer men due to World War I and II
 4. More women due to: a. longer life expectancy and b.
World Wars (I and II)
 5. More 75-79 yrs than 0-4 yrs. Signs of a future worker
shortage and an overall declining population.
Thomas Malthus on Population
An Essay on the Principle of Population, 1798
Malthus predicted population
would outrun food supply,
leading to a decrease in food
per person.
300
250
200
Population
150
Assumptions
 Populations grow exponentially.
 Food supply grows arithmetically.
 Food shortages and chaos inevitable.
Food
100
50
0
1
2
3
Food
2
4
8
16
4
Population
2
4
16
256
Neo Malthusians People who support Malthus’
original hypothesis but tweaked the theory
 Malthus failed to include LDCs in his
theory
 LDCs entered stage 2 not because of
wealth but because of medical
revolution
 Overpopulation affects not just food
production but also other resources
 Population will continue to rise in
LDCs therefore people will be fighting
over resources not just food
Critics of Malthus
 Possibilism allows for
 Higher population for
humans to change
environment
 Larger population
stimulates economic
growth and ideas
 Marxists believe poverty
and hunger are a result of
unjust social institutions
national defense (armies)
 Capitalism creates
unequal access to
resources
Epidemiological Transition
 Created by Abdel Omran in 1971
 Follows the DTM but looks at the health threats of each
stage
 Explains the CDR of each stage
 Later the model was modified for stage 4 by Olshansky
and Ault
 The modification was to take into account the impact of
medical advances that keep people alive
Epidemiological Transition
 Stage 1 Pestilence and famine
 High CDR
 Black Plaque
 Stage 2 Pandemics
 Rapidly declining CDR
 Cholera
 Controlled with improved
sanitation
 Stage 3 degenerative diseases
 Moderately declining CDR
 Cardiovascular disease, heart
attacks
 Stage 4 (delayed stage 3)
 Low but increasing CDR
 Life expectancy was longer
due to medical advances
 Possible stage 5 reemergence
of stage 1 (infectious and
parasitic diseases)
 Mutation of diseases
 poverty decreases sanitation
 increased travel to spread
new contagions like Malaria,
TB and SARS
Population Futures
 Two ways to lower CBR
 Increased economic development provides better education and
health care
 Improve a country’s economy
 Increase country’s literacy rate
 Increase girls’ access to education and jobs
 Increased health care to lower IMR
 Distribution of contraceptives and education about family planning
 Sexual education
 Access to birth control (contraceptives)
 Bangladesh, Colombia, Morocco and Thailand have low literacy rates but
access to birth control
 25% of women in sub Saharan Africa use contraceptives
Summary
 Overpopulation is a
 Countries experience
relationship between the
size of the population and a
region’s level of resources
 CBR must be reduced in
order to curb global
population growth
different population and
epidemiological transitions
 Malthus was only partly
correct
 LDCs increasing
populations make up for
MDCs declining
populations