1. AP Human Geography Review
Theories and Models

2. The Demographic Transition Model

3. Stage One
High birth rates
High death rates
Slow population growth

4. Stage Two Falling death rates Continuing high birth rates
Population increases rapidly

5. Stage Three
Birth rates slow
Population growth rate slows down

6. Stage Four Low birth rates Low death rates
Low rate of natural increase.

7. Stage Five? Population decrease?
Such low birth rates that there are actually negative population growth rates in countries that have fallen below replacement TFR.

9. Ravenstein's Laws of Migration
Ravenstein came up with his "laws" of migration in the 1880s based on studies carried out in the UK.
The laws are as follows
The greatest body of migrants travel short distances.
This produces currents directed towards large commercial centres.
Each current has an off-setting counter-current in the opposite direction.
Both currents display similar characteristics
Long distance movements are directed towards large commercial centres.
People in urban areas migrate less than people in rural areas.
Males migrate more over long distances and females migrate more over short distances.
Additions to These Laws
Most migrants are between years of age.
People mainly move for economic reasons.
Urban housing development is inadequate for the influx of migrants so ghettoes/shanties are formed.

10. Agriculture Theory
With increased food supply and increased population, speakers from the hearth of Indo-European languages migrated into Europe.

11. Gravity Model Push-Pull Theory
This theory states that larger towns are more attractive to immigrants than smaller towns.
Push-Pull Theory
Any migration is as a result of push forces at the origin and pull forces at the destination.
Examples of push forces are famine, war and poverty.
Examples of pull forces are availability of food, peace and wealth.

12. Consequences of Migration
Demographic Consequences:
Changes in the numbers and distribution of people within a region are changed.
Intermarriages are created, leading to a new group of people.
Social Consequences:
Migration brings different people together leading to conflicts.
Migration however also creates understanding between different groups of people.
Rural-Urban migration creates ghettoes in cities.
Economic Consequences:
This depends on the "quality" of the migrants and the economic needs of the origin and destination. Quality refers to skills, age, educational attainment, health etc.
In overpopulated areas, emigration is beneficial because it reduces the pressure on the land.
In under-populated areas, emigration may slow down development.

13. Dispersal Hypothesis
Indo-European languages first moved from the hearth eastward into present-day Iran and then around the Caspian and into Europe.

14. Renfrew Hypothesis:
Proto-Indo-European began in the Fertile Crescent, and then:
From Anatolia diffused Europe’s languages
From the Western Arc of Fertile Crescent diffused North
Africa and Arabia’s languages
From the Eastern Arc of Fertile Crescent diffused Southwest
Asia and South Asia’s languages.

15. Development Models Modernization Model
Walt Rostow’s model assumes all countries follow a similar path to development or modernization, advancing through five stages of development, climbing a ladder of development.
- traditional
- preconditions of takeoff
- takeoff
- drive to maturity
- high mass consumption

16. Rostow’s Ladder of Development

17. Dependency Theory
The political and economic relationships between countries and regions of the world control and limit the economic development possibilities of poorer areas.
Economic structures make poorer countries dependent on wealthier countries.
Little hope for economic prosperity in poorer countries.
Relates to neocolonialism

18. Von Thünen Model

19. Von Thűnen Model

20. Von Thunen’s model is the beginning of location economics and analysis (1826)

21. Immanuel Wallerstein’s World-Systems Theory states:
The world economy has one market and a global division of labour.
Although the world has multiple states, almost everything takes place within the context of the world economy.
The world economy has a three-tier structure.

22. Construction of the World Economy
Capitalism – people, corporations, and states produce goods and services and exchange them in the world market, with the goal of achieving profit.
Commodification – the process of placing a price on a good and then buying, selling, and trading the good.
Colonialism – brought the world into the world economy, setting up an interdependent global economy.

23. The Three Tier Structure
Core
Processes that incorporate higher levels of education, higher salaries, and more technology.
Generate more wealth in the world economy
Periphery
Processes that incorporate lower levels of education, lower salaries, and less technology
Generate less wealth in the world economy
Semi-periphery
Places where core and periphery processes are both occurring. Places that are exploited by the core but then exploit the periphery.
Serves as a buffer between core and periphery

24. World Systems Theory

25. Ratzel’s organic theory of the state
The Germans were instrumental in developing the field of Geopolitics (Geopolitk).
In 1897, the German geographer Friedrich Ratzel developed his "organic theory". This theory contend that the state is like an organism attached to the earth that competes with other states to thrive.
Like all living organisms, the state needs lebensraum - living space.

26. Mackinder’s Heartland Theory
Sir Halford John Mackinder was a British geographer who wrote a paper in 1904 called "The Geographical Pivot of History." He suggested that control of Eastern Europe was vital to control of the world. He formulated his hypothesis as:
Who rules East Europe commands the Heartland
Who rules the Heartland commands the World-Island
Who rules the World-Island commands the world
Mackinder's Heartland the Pivot Area) is the core area of Eurasia, and the World-Island is all of Eurasia (both Europe and Asia).

27. Mackinder’s Heartland Theory

28. Location Theory
Location Theory – seeks to predict where businesses or industries will or should be located.
Considers:
Variable costs
Friction of distance

29. Location Models Weber’s Model Hotelling’s Model Losch’s Model
Manufacturing plants will locate where costs are the least (least cost theory)
Theory:
Least Cost Theory
Costs: Transportation, Labour, Agglomeration
Hotelling’s Model
Location of an industry cannot be understood without reference to other industries of the same kind.
Theory:
Locational interdependence
Losch’s Model
Manufacturing plants choose locations where they can maximize profit.
Theory:
Zone of Profitability

30. Losch’s Model

31. Central Place Theory
Walter Christaller developed a model to predict how and where central places in the urban hierarchy (hamlets, villages, towns, and cities) would be functionally and spatially distributed.
Christaller assumed that:
surface is flat with no physical barriers
soil fertility is the same everywhere
population and purchasing power are evenly distributed
region has uniform transportation network
from any given place, a good or service could be sold in all directions out to a certain distance

32. Hexagonal Hinterlands
C = city
T = town
V = village
H = hamlet

33. Modelling the North American City
Concentric zone model (Ernest Burgess)
Sector model (Homer Hoyt)
Multiple Nuclei Model (Chauncy Harris and Edward Ullman)

34. Three Classical Models of Urban Structure

35. Urban Realms Model
Each realm is a separate economic, social and political entity that is linked together to form a larger metro framework.

36. Latin American City (Griffin-Ford model)

37. The African City (de Blij model)

38. Southeast Asian City (McGee model)