Introduction to
Geography
People, Places, and Environment, 6e
Carl Dahlman
William H. Renwick
Chapter 6: Population, Population
Increase and Migration
Holly Barcus
Morehead State University
And Joe Naumann
Umsl
Population
• Population geography
– Distribution of humankind
• Emigration
• Immigration
• Demography
– Specific group characteristics
2
Distribution and Density
•
Current World Population
– 6.3 billion
•
Major concentrations – ranked by size
1.
2.
3.
4.
5.
East Asia
South Asia
Europe from the Atlantic to Ural mountains
Eastern United States and Canada
Southeast Asia
3
World Population Cartogram
3
4
1
2
5
Population Density
• Arithmetic density
– Number of people per unit of area
• Physiological density
– Density of population per unit cropland
• Carrying capacity
The numbers of any population that can be
adequately supported by the available resources
upon which that population subsists; for humans,
the numbers supportable by the known and
utilized resources – usually agricultural – of an
area. [closely related to physiological density].
5
Definitions:
• Birth Rate (crude birth rate) – Expressed as the
number of births per year per 1000 population
• Total Fertility Rate – The average number of
children that would be born to each woman if
during her child-bearing years, she bore children at
the current year’s rate for women that age.
Replacement rate is 2.1.
• Death Rate (crude death rate) – Expressed as the
number of deaths per year per 1000 population.
Also called mortality rate.
6
More Definitions:
• Infant Mortality Rate – Expressed as the number
of children who die between birth and one year of
age in a year per 1000 population.
• Population Pyramid – A graphic depiction of the
age and sex composition of a (usually national)
population.
• Natural Increase – The growth of a population
through excess of births over deaths, excluding the
effects of immigration or emigration. This can be a
negative number.
7
Even More Definitions:
• Doubling Time – The time period required for any
beginning total (population) experiencing a
compounding growth, to double in size.
• Population Density – the total population of a
country divided by the total area in square miles or
kilometers.
• Physiological density – (population pressure)
The number of persons per unit area of agricultural
land. This is more meaningful than population
density.
8
Factors Influencing Population
Distribution
• Climate
– Low density
– High density
• Topography and soils
– Flat areas = easier cultivation
– Accessibility to water
– Fertile soils
• History
– Domestication of plants and animals
– Demarcation of cultural and political territories
9
World Population Growth
• Crude birth
rate
• Crude death
rate
• Natural
increase
• Natural
decrease
10
Focus on the last 600 years!
11
Exponential Population Growth
12
• See Demographic Transition Stage Two
Population Explosion?
• Click on the picture to see the video
13
Projections
•
•
•
•
•
Fertility rate
Total fertility rate
Replacement rate
Zero population growth
Doubling time
14
Population Growth
Population Pyramids
– Age and sex structure of population
• Dependency ratio
– Proportion of population of working age
17
Demographic Transition
• Many developing countries are in mid to late stage 2 of
the transition.
20
Stages of Population Growth
Birth Rate
Death Rate
Growth Rate
Stage High
1
High
Stable or growing slowly -long doubling time
Stage High &
beginning to
2
decline slowly
Dropping
sharply
Continually increasing –
short doubling time
Stage Declining more Dropping but
rapidly
at a slower
3
rate
Increasing but at a
declining rate – doubling
time still rather short
Stage Low
4
stability, or declining – long
doubling time
Low
21
Demographic Transition Model
• Stage one
– Crude birth/death rate high
– Fragile population
• Stage two & three
– Decreasing death rates – birth rate decreasing in stage
3 too
– Infant mortality rate high – declining in stage 3
– Natural increase high – declining in stage 3
• Stage four
– Indicative of richer developed countries
– Higher standards of living/education
22
Population Growth
• The meaning of large numbers is relative to
a number of factors in each country.
– Rate of natural increase
– Average life expectancy
– Carrying capacity or physiological density
– Technological level of the culture and the level
of infrastructure development
• Increased physiological Density – increased
population pressure
25
Growth – China & USA
• China
– A 1% growth rate in China means 12,552,910
more people the next year and slightly more the
next.
– Arable land (hectares per person) 0.10
• USA
– A 1% growth rate in the USA means 2,737,540
more people next year and slightly more the
next.
26
– Arable land (hectares per person) 0.67
Pressure on the Land
• Terraced rice paddies are very labor-intensive –
27
not a first choice method.
Carrying
Capacity
28
Central America
What
accounts for
growth
here?
29
Canada’s population
• Why the
strange
pattern?
30
Population Growth
Projection
31
Population Structure
• Broad base
and narrow
top will
mean high
growth rate
• Yellow:
stage 4
• Red: stage
2&3
32
Selected Countries: Patterns
33
China’s Population Policy
• Under Mao
Zedong – no
emphasis on
reducing
population growth
rate.
• Under Deng
Xiaoping – Onechild per family
policy.
34
The Demographic Transition
• The Western Experience – Four stages are
based on the European experience
• Today, we live in a world divided.
– Developed vs. developing countries
– Effects of urbanization and industrialization are
taking longer to influence population growth
rates in the developing countries.
– Developing countries are not experiencing a
gradual shift resulting from technological and
social changes occurring within their culture – it
is more a response to outside influences.
35
Difference in Transitions
36
37
Urbanization – Developed World
• Europe & North America grew with the
industrial revolution – lower birth rates in
urban areas of developed countries.
38
Urbanization –Developing World
• Asia, Africa, Latin America, etc. increased as an alternative
to rural poverty or famine, but there often wasn’t enough 39
industrial development to provide jobs – favelas and barrios
Life Expectancy
• Infant mortality rate
• Antibiotics/immunization
• Rapid increase throughout world
40
Population - Developed Countries
42
Infant Mortality Rates
43
New Influences on Birth Rates
• Family planning programs
• Contraceptive technology
• Role of mass media
44
Declining numbers of school-age children in some
Asian countries – 2000 – 2020 CE
What’s
different
about these
countries?
45
Population Control
• Obstacles
– Manufacture/distribution expense
– Religion
– Low female status
– Preference of male children (females
marry and join their husband’s family)
46
Birth Control Programs
• One family/one child policies (China by law)
– Female infanticide
– Social compensation fees
•
•
•
•
•
Sterilization (India: of men by persuasion)
Loss of status
Termination healthcare/food coupons
Free birth control
Increased literacy – important for success
47
Population Data and Projections
• Population Data Sources – not always clear
– United Nations
– World Bank
– Population Reference Bureau
– National censuses --
• Population Projections – estimates of future
population size, age, and sex composition
based on current data. Based on observed
trends.
48
Based on Census Data
Projected Growth
49
World Death Rates
• Infectious diseases
– HIV/AIDS
– SARS – affects lung mechanics
• Degenerative diseases
– Obesity – more serious in developed countries like USA
– Tobacco use – legal, insidious, money-making addiction
• Epidemiology –
– all the elements contributing to the occurrence or
nonoccurrence of a disease in a population; ecology of a
disease
• Epidemiological transition – infectious to degenerative50
Estimated Number of Persons of
Concern Who Fall Under the Mandate
of UNHCR
Overpopulation?
• Malthus and Neo-Malthusianism – Sees a direct relationship
between the size of population and the means of
subsistence.
– Dire predictions were not realized because N. & S. America were
discovered and could greatly increase the world’s carrying capacity
– for a time
– Can technology be counted on to forever push back the perceived
limits on food production and pollution control?
• Cornucopians
– Optimistic perspective: technology will find a way, somehow
– Jean Antoine Condorcet
• Analogy of “fruit fly jars”
52
Overpopulation?
• Overpopulation – relative term – according to
whose perceptions? Has some relationship to
carrying capacity or physiological density
53
Cartogram 1995 population
• Note Africa & Asia
54
Cartogram 2030 population
• Note Africa & Asia
55
Population Prospects
• Worldwide Fertility Declines –
– Effects of urbanization
– Government programs – India, Singapore, China
• Implications of Demographic Momentum
– Age structure is significant in keeping growth
going – large populations below age 15 keep
growing – improved health extends the time in
which they may procreate
• The Aging of World Population
– Even in developing countries – exceeding
developed ones – Must be supported by the
young . . .
56
Demographic Patterns
• Sex ratios
– Effects of
• Ultrasound, amniocentesis
• Male status
• Aging
– Increased median age
– Rich countries
• Sustaining economic growth
• The “sandwich generation”
• Medical needs
– Poor countries
• Young populations
• Changing social needs
57
Spatial Behavior –
Migration &
Immigration
Spatial Behavior
• Affected by perceptions
• Affected by sense of space
– Personal
– Community
• Aspect of culture
59
Mental Maps – personal perception
of reality
• Vary greatly according to one’s experiences
& interests & reaction to distance decay
– Influence our actions and decisions
– Fred Broer’s visit to St. Louis -- 1965
• I was raised in N. St. Louis and N. St. Louis
County
– I have a fairly accurate mental map of those
areas
– S. St. Louis and S. St. Louis County are much
less accurate in my mental map
60
Perception of Natural Hazards
• Earthquakes, tornadoes, hurricanes,
tsunami, mudslides, etc.
• Why do people choose to live where they
occur?
– Great River Road north of Alton, IL
• What they know – it’s home.
• Hazards occur infrequently – another “flood of 93” isn’t
expected for a long time.
• Prohibitive cost of relocation
61
Activity Space
• Personal Activity Space – realm of free
movement
• Territoriality – emotional attachment to an
area
– Personal space varies according to cultures
– Ethnic neighborhoods – some persist for a long
time
62
3 variables affect activity space
• Stage in Life Course – age-group
membership parameters
• Mobility – ability to travel
– Personal ability – ownership of mode of
transport and/or funds
– Public access available?
• Opportunities – related to infrastructure
and income
– Few in a subsistence economy
– Many in urban/industrialized economy
63
Spatial Interaction and Information
• Barriers to Interaction
– Distance – technology affects the parameters
– Natural obstacles – rivers, mountains, etc. – important
role of technology
• Spatial Interaction & Innovation – centers of high
interaction became culture hearths – ideas easily
cross-pollinated there
–
–
–
–
Middle East—Eastern Mediterranean
Huang He Valley—Indus Valley
Meso-America & Altiplano
Europe since the Renaissance
64
MIGRATIONS
Migrations are as old as humanity
• Early Humans migrated from Africa and
spread to the other land masses of the
world
• Native Americans migrated across the
Bering land bridge.
• Africans migrated, against their will, to the
new world
• The Bantu people migrated and populated
from West Africa to South Africa
66
Migration
• Push factors
– Drive away
people
• Pull factors
– Attract
people
• Migration
chains
67
Decision Process
• Spatial Search – process by which
alternatives are evaluated
– Influenced by information available
• Quality
• Quantity
– Influenced by the utility assigned to
places and the opportunities at those
places
• A cost/benefit analysis of sorts
• Push & Pull factors can work both ways
68
Migration of Peoples
•
•
•
•
•
•
•
Prehistoric
Europe to the Americas
African diaspora
Europe to Asia & Oceania
Europe to Africa
Indian
Overseas Chinese
69
Prehistoric Human Migrations
Crossing Beringia (land bridge)
• Most ancestors
of Amerindians
are believed to
have come to
the Americas via
Beringia (the
Bering Strait)
71
Early Migrations – Aegean Sea
72
Overseas Chinese Migration
73
Early Pacific Migrations
74
Barbarian invasions of Rome
75
Gateway for a Major Migration
76
Slave Trade
European Migration -19th Century
Europe after 1945
• From less to
more
prosperous
coutnries
• “Guest
workers”
– Often men
• Worker’s
remittances
79
1950
1990
Change in African-American
Population 1950-1990
80
Different Scales of Migration
•
•
•
•
Local – Urban to Suburban
State – Rural to Urban/Suburban
Regional – Rust Belt to Sun Belt
International – Country to Country
– Legal immigration
– Illegal immigration
• WHATEVER THE SCALE, SOME TYPE OF
PUSH AND/OR PULL FACTORS WERE
INVOLVED IN THE DECISION.
81
Reasons Americans Migrate
• Changes in life course – marriage, etc.
• Change in career cycle – leaving college, job
transfer
• Forced migrations – urban development,
construction projects, etc. such as airport
expansion
• Neighborhood changes from which some choose
to flee
• Changes associated with individual personality
• Historically part of our culture
82
Barriers to Migration
•
•
•
•
Physical – terrain, deserts, oceans
Economic – cost increases with distance
Lack of knowledge of opportunities
Roots – ties to individuals and institutions in the
original activity space
• Regulations in the receiving country (may not be
too effective) and military resistance
• Psychological – perceptions of distance and
difficulty
• Government regulations against emigration
83
(former Soviet “Bloc”)
84
85
Government Policy?
• In the light of September 11, 2001, there will be much
debate about immigration policy. Most of us are glad
the door was open to our ancestors; however, . . . . . . .
86
Patterns of Migration
• Migration field – An area that sends or
receives major migration flows
– Channelized pattern of flow – persistent patterns
– Influence of past patterns of flow
– Job opportunities & Economic influences
– Ethnic affinity
– Return migration –shortly after migrating decide
to return (in free conditions, 25%)
• #1 false expectations & #2 adjustment problems
– Hierarchical migration
• People moving up the levels of urban hierarchy
from small places to large ones
87
Notable Migrations
•
•
•
•
•
•
•
•
•
•
•
•
Ancestors of Amerindians
Phoenicians & Greeks around the Mediterranean
Norsemen (Normans)
Europeans to the “New World” and Australia
Russians eastward into Siberia
European Americans westward in USA
Afro-Americans from south to north & urban centers
Bantu migration to south and east in Africa
Chinese to southeast Asia & islands
Afrikaners to the high Veldt
U.S. “Rustbelt” to the “Sunbelt”
Mexicans to the U.S. southwest (illegals)
88
Migration Today
• 2002 = 175 million living outside country of birth
• Characteristics
– Many poor, uneducated, unskilled
– Enterprising, working age looking for opportunity
– Many also highly educated and skilled
• Refugees
– 1951 Geneva convention
– Asylum
89
International Migration
• Increased apprehension in receiving countries
– “Compassion fatigue”
– Immigrants are scapegoats when unemployment rises
• Emigration
– Importance of remittances
• Mexico = 3rd largest source of foreign exchange
90
International Migration
• Europe as a destination
–
–
–
–
16 million immigrants
7-10 percent of host country population
Problems = religion, education
Contributions = entrepreneurs
• Migration of Asians
– 4-5 million work abroad
– Remittances important
– Loss to home communities
91
Migration to the US and Canada
• US
–
–
–
–
Largest migration flow to US
10% US population foreign born
Immigration quotas restrict immigration
Implications
• Hispanics as proportion of US population
• Canada
– 18.4 percent population foreign born
– 94 percent live in metro areas
92
Source of
immigrants to the
USA
Foreign-born
population in the
USA by region
of birth
New Controversies
• Additional costs for public services?
• Importing poverty?
• Local costs of immigration
– California
• “Melting pot” or “cultural mosaic”?
94
Global Warming & Migration
• Climate change has spurred past migrations
– Oakies of U.S. dust bowl era
– Huns in 5th century CE
– Ice ages
• The major effect of global warming is expected to
be climate change; however, no one can
accurately predict what changes will occur where
and to what extent?
• Might this trigger new migration patterns?
95
The Demographic Equation
• Demographic equation summarizes the
contribution made to regional population change
over time by the combination of natural change and
net migration.
– Population Relocation – immigration/emigration – two
sides of a movement
– Immigration Impacts on the demographic equation –
increases as the population size of the areal unit studied
decreases
– TP = Natural Increase + Immigration - emigration
96
End of Chapter 5
97