1. Demographic Transition Model (DTM)

2. Key Vocabulary Crude Birth Rate (CBR) Crude Death Rate (CDR)
Natural Increase Rate (NIR)
Also RNI
Total Fertility Rate (TFR)
Infant Mortality Rate (IMR)
Life Expectancy
Doubling Time

3. Defined
CBR: total number of live births in a year for every 1,000 people alive in the society
CDR: the total number of deaths in a year for every 1,000 people alive in the society
NIR: the percentage growth of a population in a year, computed as the crude birth rate minus the crude death rate
TFR: the average number of children a woman will have throughout her childbearing years
IMR: the total number of deaths in a year among infants under 1 year old for every 1,000 live births in a society
Life Expectancy: the average number of years an individual can be expected to live, given current social, economic & medical conditions. Life expectancy at birth is the average number of years a newborn infant can expect to live.
Doubling Time: The number of years needed to double a population, assuming a constant rate of natural increase

5. Population
Demographic transition model
The demographic transition model shows how a population will change over time as it changes from an agrarian society to an industrial, and post-industrial one.

6. Population
Demographic transition model
The demographic transition model shows how a population will change over time as it changes from an agrarian society to an industrial, and post-industrial one.
Stage 1.
Birth and death rates are both high, leading to a low but stable population.
High fluctuating
UK pre 1760/Industrial Revolution.
Remote tribal groups presently.

7. Population
Demographic transition model
The demographic transition model shows how a population will change over time as it changes from an agrarian society to an industrial, and post-industrial one.
Stage 2.
Birth remain high but now death rates start to fall dramatically, leading to a rising population.
Early expanding
UK pre
Peru/Sri Lanka/Kenya presently.

8. Population
Demographic transition model
The demographic transition model shows how a population will change over time as it changes from an agrarian society to an industrial, and post-industrial one.
Stage 3.
Birth start to fall now and death rates continue to fall, causing the population to continue to rise but less quickly now as the gap between births and deaths is closing.
Late expanding UK
China/Cuba/Australia presently.

9. Population
Demographic transition model
The demographic transition model shows how a population will change over time as it changes from an agrarian society to an industrial, and post-industrial one.
Stage 4.
Birth and death rates are now both low, causing the population to be more stable but high.
Low fluctuating
UK post 1940
Canada/USA/Japan.

10. Stage 1 – High Fluctuating
High CBR
High CDR
Reasons:
High IMR
Lack of family planning
Need for workers
Children are economic assets(support parents)
Religious beliefs
Roman Catholics
Muslims
Hindus
Reasons:
Disease
Famine
War
Poor hygiene & sanitation
Lack of healthcare
Lack of education

11. Population
Demographic transition model
Stage 1.
Natural increase (population growth) is low because although there are a lot of births the similarly high number of deaths effectively cancels them out, leaving a low but stable population.

12. Stage 2 – Early Expanding
Same reasons as Stage 1
High CBR
Declining CDR
Reasons:
Improved healthcare
Improved sanitation
Improved food production
Decreasing IMR
Outside stimulus

13. Population
Demographic transition model
Stage 2.
Natural increase (population growth) is high because there is now a large gap between births and deaths, increasing the population rapidly.

14. Stage 3 – Late Expanding Same reasons as Stage 2 Declining CBR
Declining CDR
Reasons:
Changing status of women
Cairo Conference
Availability of family planning
Lower IMR
Increased standard of living
Better technology = lower demand for workers
Welfare/Retirement

15. Population
Demographic transition model
Stage 3.
Natural increase (population growth) remains high due to the gap between births and deaths but as this stage the increase slows as births and deaths match up again.

16. Stage 4 – Low Fluctuating
Stage 4…and 5?
Stage 4 – Low Fluctuating
Stage 5
CBR & CDR are low
Population is stable
CBR drops below CDR
Population starts to decrease
Officially only 4 stages
Not part of the original DTM, but some geographers have added it
So if there is 5, why not 6?

17. Population
Demographic transition model
Stage 4.
Natural increase (population growth) is again low as births and deaths virtually cancel each other out, but now the population is high..

19. Population Concentrations
East Asia
South Asia
Europe
Southeast Asia
Northeast North America
West Africa

20. East Asia Eastern China, Japan, Korean peninsula & Taiwan
¼ World’s Population
5/6 live in PRC
China: ½ of population work as farmers (rural)
Japan & Korea
40% live in 3 major cities (Tokyo, Osaka, & Seoul)

21. South Asia India, Pakistan, Bangladesh & Sri Lanka ¼ World Population
¾ live in India
Most are farmers in rural areas

22. Europe 3rd Largest (including European portion of Russia)
1/9 of world population
¾ live in cities
> 10% farmers

23. Southeast Asia Indonesia, Papua New Guinea & Philippines
Largest = Java = 100 million
Most work as farmers in rural areas

24. Emerging Population Concentrations
Eastern North America
West Africa
NE U.S. & SE Canada
2% of the world’s population
Most urbanized concentration
>2% farmers
West Africa, including south facing coast & Nigeria
2% of the world’s population
Nigeria = most populous African nation, ½ of this concentration
Most work in agriculture

25. Population Density Arithmetic Density Physiological Density
Agricultural Density

26. Arithmetic Density
“The total number of people divided by the total land area”
Pros
Easy to compare
Cons
Tells us “where,” but not “why”

27. Physiological Density
“The number of people per unit of area of arable land, which is suitable for agriculture”
Pros
More meaningful
Cons
Higher = more pressure to produce more food

28. Agricultural Density
“The ratio of the number of farmers to the total amount of land suitable for agriculture”
MDCs
Lower agricultural density
Fewer farmers, more extensive areas
Due to better technology & finances

29. Overpopulation
Carrying Capacity is the ability of a resource base to sustain a population
Overpopulation
Too many people compared with the resources of region/country

30. Thomas Malthus Thomas Malthus Theory English economist
Determined the world’s rate of population increase was higher than the development of food supply
Theory
Population grows geometrically
Food grows arithmetically

31. Neo-Malthusians
Argue that recent growth is worse than Malthus projected
Malthus’ theory is almost 200 years old
Many LDCs are progressing due to help from MDCs rather than progressing on their own
Bigger gap between population & resources
World population is outpacing other resources other than just food
Environmental destruction
Lack of land
Non-renewable energy

32. Critics Possibilism Technology Growth = more production
Growth = more new inventions

33. Population Pyramids: How they work…
Males on the left, females on the right
Youngest on the bottom (0-4), oldest on the top (100+)
Generally done as a percentage of the population, sometimes as total numbers
Shape of the pyramid is generally shaped by the CBR in a country

34. Population Pyramids & DTM
Population Pyramids and the DTM can generally by applied together
Certain shapes have been associated with specific stages of the DTM

35. Pyramid for Stage 1 Wide base = very high birth rate
Narrows very quickly = high death rate
Very few reach old age

36. Pyramid for Stage 2 Wide base = High birth rate
Wider & taller = people living longer

37. Pyramid for Stage 3 “Domed” shape = more people living to be older
Proportionately fewer births

38. Pyramid for Stage 4
Small base, small top
Bulge in the middle

39. All four Stages
Convex Profile
Concave Profile

40. 8 Great Modern Migrations

41. Ravenstein’s Laws of Migration
British sociologist (1834 – 1913)
Laws of Migrations:
Most migrants go only a short distance
Distance Decay
Most migrations proceed step-by-step (Lee’s Model)
If they do move a long distance, they are more likely to travel to a big city (Gravity Model)
Every migration flow produces a counterflow
Rural migrants move to city; city dwellers move to suburbs
Most migration is from rural to urban
Families are less likely to make international moves than young adults
Most international migrants are young males
Changed with time; women comprise 40-60% of International migrants (55% of U.S. migrants)

42. Types of Migration Voluntary Migration Forced Migration
Choose to migrate
Remember
Must be permanent
If they return (guest workers, time-contract workers) they are not included in these numbers
a.k.a. Involuntary migration
Examples:
Triangle Trade
Atlantic Arm
Native American relocation in Great Plains region of U.S.

43. Global Migration Trends
From less-developed Stage 2 countries
To more-developed Stage 4 countries
3 largest migration flows
Asia to Europe
Asia to North America
Latin America to North America
Net In Migration: Europe, North America & Oceania
Net Out Migration: Asia, Latin America & Africa

44. U.S. Immigration Trends 3 Phases American colonies
European settlement, mainly British
African slaves
Nineteenth-Twentieth Century
: Western Europe
1880s: Northern Europe
Beginning of Twentieth Century: Southern & Eastern Europe
2nd Half of Twentieth Century
Latin America & Asia
Periods of Decline
U.S. Civil War, 1893 Depression, WWI, Great Depression, WWII

45. Key Terms Defined
Push Factor: Factor that induces people to leave old residences.
Pull Factor: Factor that induces people to move to a new location.
Intervening Obstacle: An environmental or cultural feature of the landscape that hinders migration.
Intervening Opportunity: A favorable environmental, economic or cultural feature that redirects migration.

46. Lee’s Model of Migration
Destination
Source Region
Push Factors 1. 2. 3. 4. 5. 6. 7. 8.
Pull Factors 1. 2. 3. 4. 5. 6. 7. 8.
Intervening
Obstacle
Migration

47. Push/Pull Factors Economic Environmental Cultural
Economic & Environmental push/pull factors are generally associated with voluntary migration.
Cultural push/pull factors are generally associated with forced migration
Note: people tend to move on excessively positive images/expectations that may not always be accurate

48. Push/Pull Factors Push Factors Pull Factors Economic Environmental
Poverty
Few job opportunities
Low wages
Environmental
Hazardous regions
Adverse physical conditions
Too little water/too much water
Cultural
Slavery
Political instablity
Religious/ethnic persecution (refugees)
Economic
Higher standard of living
More job opportunities
Higher wages
Environmental
Stable climates
Cultural
Stable political conditions

49. Intervening Obstacle/Opportunity
Examples of Obstacles
Environmental
Mountains, rivers, bodies of water, etc.
Cultural
Passport to leave/visa to come in
Economic
Run out of money
Examples of Opportunities
New jobs along migration route
Jobs created to divert rivers for irrigation (economic as well)
Move into an ethnic enclave along route

50. Practical Application of Lee’s Model
Source Region
Destination Region
Return
Pull Factors +
Push Factors -
Intervening Obstacle
Pull Factors +
Push Factors -
Migration
Few Arrive
Many leave
Intervening Opportunity
Other Destination

51. Background
Interaction is proportional to the multiplication of the two populations divided by the distance between them (distance decay); based on Newton’s Law of Gravity