MODELS AND THEORIES
Concentric Zone Model (Burgess Model)
Developed by: Ernest W. Burgess in the 1920s
Description: Urban land use in concentric rings around a Central Business District (CBD).
Zones Explained:
Zone 1: Central Business District (CBD)
Core of the city; high land value and intense economic activity.
Zone 2: Zone of Transition
Mixed-use area with light industry and lower-income housing; signs of urban decay.
Zone 3: Zone of Working-Class Homes
Residential areas for blue-collar workers, new immigrants, and singles.
Zone 4: Zone of Better Residences
Spacious, higher-quality homes for middle-class families.
Zone 5: Commuter Zone
Suburban areas for higher-income families commuting to the city.
Social Class Distribution:
Illustrates socio-economic stratification from lower to upper classes.
Applications:
Chicago, USA: Often cited as a classic example, where the concentric zones illustrate socio-economic distribution.
Sao Paulo, Brazil: Shows similar urban structures with clear CBDs and socio-economic stratification.
London, UK: Displays a clear concentric zoning structure with socio-economic implications.
Buenos Aires, Argentina: Presents a pattern with distinct CBD and varied residential zones.
Mumbai, India: The concentric model is evident with high-density informal housing surrounding a central business area.
Decline in Use:
The model began to decline in use by the 1970s as cities became more complex and diversified.
Sector Model (Hoyt Model)
Developed by: Homer Hoyt in 1939
Description: Urban land use arranged in sectors or wedges radiating from the CBD.
Key Features:
Arrangement based on transportation access and economic activities.
Higher-income residences are located in specific sectors; lower-income areas near light industry.
Transportation lines influence locations of residential and industrial areas.
Example:
Twin Cities area shows distinct residential wedges based on class accessible via major routes.
Applications:
Los Angeles, USA: The layout resembles Hoyt’s model with sectors influenced by transportation networks and class stratification.
London, UK: Displays sectors around transportation lines, illustrating the Hoyt Model's application.
San Francisco, USA: The urban layout shows clear sectoring based on socio-economic class and transportation.
Toronto, Canada: Residential patterns follow the Hoyt model with transportation routes influencing the socio-economic distribution.
Kuala Lumpur, Malaysia: The urban sectors are evident with various economic activities interspersed based on transportation access.
Decline in Use:
The model saw a decline in use during the 1980s as urban landscapes became increasingly heterogeneous and multifaceted.
6. Multiple Nuclei Model (Ullman Model)
Developed by: Chauncey Harris and Edward Ullman in 1945
Description: Recognizes that cities can grow around several centers, not just the CBD.
Characteristics:
Development based on various nodes (universities, airports, commercial centers).
Emergence of edge cities around major highway intersections with their own commercial hubs.
Highlights complexity and variation in urban forms across cities.
Example:
Twin Cities development patterns around major freeways show a "multiplier effect" with dense commercial services at optimal locations.
Applications:
Atlanta, USA: Multiple centers of growth and edge cities are present, evident in its urban layout.
Toronto, Canada: Experiences similar patterns with different activity nodes around the city.
Dallas-Fort Worth, USA: The metropolitan area shows distinct growth centers with developments around highways and commercial hubs.
Los Angeles, USA: A clear example of multiple nuclei as the city expands around various centers, including cultural and economic nodes.
Sydney, Australia: Urban growth is characterized by spread across multiple centers rather than a single CBD.
Decline in Use:
This model saw diminished relevance by the 1990s as urban growth became increasingly decentralized and complex.
Conclusion
The three models help understand urban spatial organization and socio-economic patterns in the U.S.:
Concentric Zone Model emphasizes social strata in layered zones.
Sector Model highlights accessibility and transport routes.
Multiple Nuclei Model illustrates a decentralized urban form.
Central Place Theory
Creator: Walter Christaller
Year: 1933
Purpose: Explains how and why cities and towns are spaced and organized based on the services they provide.
Key Concepts:
Central places serve surrounding areas with goods and services.
Settlements are organized in a hierarchy based on the level of services.
Uses hexagonal market areas to show ideal service coverage without overlap.
Assumes an isotropic (flat and featureless) plain for simplicity.
Key Vocabulary & Why It Fits
Central Place – Core to the theory; explains the location where services are concentrated.
Threshold – Important because a minimum population is needed to sustain services.
Range – Helps determine how far people are willing to travel, which defines the size of the service area.
Hierarchy – Shows the structured levels of settlements (village, town, city) based on services.
Hexagonal Market Area – Explains efficient, equal coverage without gaps or overlaps—essential to Christaller’s ideal layout.
Hinterland – Defines the dependent area served by a central place, showing its influence.
Urban Hierarchy – Fits the model by showing how larger places offer more services.
Functional Region – The model operates on the idea that cities are functional regions organized around a central node.
Applications:
Used in urban planning to locate hospitals, schools, malls, etc.
Applied in various countries for regional planning and development.
Modern mobility and digital services have made it less strictly applicable.
Gravity Model
Developer: Adapted by William J. Reilly in 1931; generalized in geography in the 1940s–50s
Purpose: Predicts spatial interaction (like migration or trade) based on population size and distance.
Key Concepts:
Based on Newton’s law of gravity.
Interaction increases with size and decreases with distance.
Formula: Interaction = (Pop1 × Pop2) / Distance²
Key Vocabulary & Why It Fits:
Distance Decay – Key to understanding why farther places interact less.
Spatial Interaction – The whole model is about quantifying these interactions.
Accessibility – Determines how likely interaction is—easier access means stronger connection.
Friction of Distance – Refers to the resistance to movement; important in how distance affects interaction strength.
Applications:
Used to model migration, traffic, trade flows, retail behavior.
Useful in urban planning and economic geography.
Still relevant, but enhanced with more detailed variables in modern models.
Rostow’s Stages of Growth
Creator: Walt W. Rostow
Published: 1960
Purpose: Describes how countries develop economically in 5 linear stages.
5 Stages:
Traditional Society – Subsistence farming, no industrial base.
Preconditions for Take-off – Infrastructure and investment begin.
Take-off – Rapid growth in a few industries, industrialization.
Drive to Maturity – Technology spreads, economy diversifies.
Age of High Mass Consumption – Shift to services and consumer goods.
Key Vocabulary & Why It Fits:
Industrialization – Central to the “take-off” stage, a key turning point in growth.
Modernization Theory – Rostow’s model is a classic example; it argues all countries follow a similar development path.
Capital Investment – Necessary during the preconditions and take-off stages.
Comparative Advantage – Countries can grow by investing in what they do best during early stages.
Consumer Society – Defines the final stage where consumer goods dominate the economy.
Applications:
Influenced global development aid and Cold War foreign policy.
Used by the World Bank and UN in guiding development strategies
Von Thünen’s Model of Agricultural Land Use
Creator: Johann Heinrich von Thünen
Date developed: 1826 (in his book The Isolated State)
Purpose: Explains agricultural land use patterns in relation to distance from a central market (city)
Key Concepts:
Land is used differently depending on distance from the market.
Assumes an isolated state with uniform land, transportation, and climate.
The cost of transportation and land value are main factors in what is grown and where.
Closer to market = perishables/high transportation cost goods; farther = durable/cheap goods.
Model Zones (Concentric Rings):
Market gardening & dairying – Perishable and expensive to transport
Forests – For fuel (wood is heavy and bulky)
Grain crops – Less perishable, cheaper to transport
Ranching/livestock – Needs lots of land, low transport cost
Key Vocabulary & Why It Fits:
Isolated state – Base assumption for the model’s uniformity
Transportation cost – Explains why certain crops are closer to or farther from the market
Land rent (bid-rent theory) – Land value decreases with distance; affects farming type
Intensive vs. extensive agriculture – Intensive near city (high yield/small land), extensive farther (low yield/large land)
Applications:
Helped early geographers understand agricultural patterns
Still used in theoretical models and rural planning
Less directly applicable today due to refrigeration, globalization, and tech
Domino Theory
Creator: U.S. government concept, strongly associated with President Dwight D. Eisenhower (1954)
Date: 1950s–1980s (Cold War era)
Purpose: Suggested that if one country falls to communism, nearby countries would follow—like a row of dominoes
Key Concepts:
Justified U.S. intervention in countries like Korea, Vietnam, and later Latin America
Based on containment theory to stop the spread of communism
Viewed the world as a battlefield for ideological influence
Key Vocabulary & Why It Fits:
Containment – Domino theory was a justification for containing communism
Proxy war – Used to describe conflicts (Vietnam, Korea) indirectly fought between the U.S. and USSR
Ideological conflict – Democracy vs. communism; the core driver of the theory
Geopolitics – The theory influenced U.S. geopolitical strategies around the globe
Applications:
Shaped foreign policy during Cold War
Led to U.S. involvement in Southeast Asia and elsewhere
Criticized after Vietnam War and collapse of USSR; theory oversimplified local complexities
Neocolonialism
Not tied to one person – A concept developed post–World War II, especially during decolonization in Africa, Asia, and Latin America
Date: Gained traction in 1950s–1970s, still discussed today
Purpose: Describes how former colonial powers and developed countries continue to dominate developing nations economically, politically, and culturally even after independence
Key Concepts:
Control is exerted through trade, investment, aid, multinational corporations, and media—not direct political rule.
Exploitation continues through unfair economic relationships and dependency.
Ties closely with dependency theory and critiques of globalization.
Key Vocabulary & Why It Fits:
Economic dependency – Developing nations rely on richer countries, keeping them in a cycle of underdevelopment
Core-periphery model – Describes how core (rich) countries benefit from the labor/resources of the periphery (poor countries)
Multinational corporation (MNC) – Modern vehicle of economic dominance
Debt-trap diplomacy – Some view international loans or aid as tools of influence/control
Applications:
Used to analyze trade relationships (e.g., Africa’s trade with former European colonizers)
Popular in postcolonial studies, development theory, and economic policy critiques
Still relevant today in debates over globalization, IMF/World Bank practices, and foreign influence
Dependency Theory
Type: Theory
Creator(s): Raul Prebisch, Andre Gunder Frank
Developed: 1950s–1970s
Purpose: To explain global inequality as a result of exploitation by developed nations.
Key Concepts:
Poor countries (the periphery) are kept in a state of dependence on wealthy nations (the core).
Exploitation is economic and structural, not just historical.
Counters the idea that all nations naturally progress toward development.
Key Vocabulary & Why It Fits:
Core-periphery – Defines exploitative global economic roles.
Underdevelopment – A result of external control, not internal failings.
Export dependency – Overreliance on raw material exports creates vulnerability.
Terms of trade – Unequal exchanges reinforce poverty.
Applications in States/Countries:
Latin America (1950s–1980s):
Countries like Brazil, Argentina, and Mexico adopted Import Substitution Industrialization (ISI) to reduce dependency on Western imports.
Policies aimed to build domestic industries by limiting imports and investing in state-led production.
Africa (Post-independence, 1960s–70s):
Nations like Ghana and Tanzania criticized global trade systems and foreign investment as forms of neocolonialism.
Leaders like Julius Nyerere used dependency thinking to promote self-reliance and state socialism.
Status (Still Used?):
Yes, in academic and activist spaces.
Still informs critiques of IMF/World Bank policies, foreign aid, and global inequality.
Sustainable Development
Type: Framework/Theory
Creator: UN Brundtland Commission
Introduced: 1987 (Our Common Future)
Purpose: Balance economic growth with environmental protection and social equity.
Key Concepts:
Three Pillars: Environmental, economic, and social sustainability.
Designed to meet present needs without harming future generations.
Foundation for Sustainable Development Goals (SDGs).
Key Vocabulary & Why It Fits:
Ecological footprint – Shows limits of human activity.
Green economy – Encourages eco-friendly economic growth.
Intergenerational equity – Ensures fairness to future populations.
Carrying capacity – Highlights environmental limits.
Applications in States/Countries:
Costa Rica (1990s–present):
Focused on renewable energy, forest protection, and eco-tourism.
Over 98% of electricity now comes from renewable sources.
Germany (1990s–present):
Adopted Energiewende, a transition to renewable energy and sustainable practices.
Bhutan:
Pursues development through Gross National Happiness, integrating sustainability with cultural values.
Norway & Sweden:
Leaders in sustainable urban planning, clean tech investment, and green infrastructure.
Status( still used?)
Yes, globally central.
Framework for UN SDGs, climate policy, and international aid programs.
World Systems Theory
Type: Model and Theory
Creator: Immanuel Wallerstein
Developed: 1970s
Purpose: Explains the global economy as a capitalist system with a core-periphery structure.
Key Concepts:
Global inequality is the result of historical and structural relationships.
The world is divided into:
Core – industrialized, dominant economies (e.g., U.S., Germany)
Semi-periphery – rising economies (e.g., Brazil, China)
Periphery – underdeveloped economies (e.g., Sub-Saharan Africa)
Key Vocabulary & Why It Fits:
Global division of labor – Countries have specialized roles in global production.
Capitalist world economy – The system prioritizes profit and maintains inequality.
Structural inequality – Built-in disadvantage for certain regions.
Semi-periphery – Important buffer zone that adds complexity to global power dynamics.
Applications in States/Countries:
China (1980s–2000s):
Moved from periphery to semi-periphery by becoming a global manufacturing hub.
Wallerstein noted China’s shift as a prime example of semi-peripheral rise.
South Korea & Taiwan:
Once considered semi-periphery, now increasingly viewed as part of the core, showing upward mobility in the system.
Nigeria and Angola:
Resource-rich but remain peripheral due to economic extraction and weak infrastructure.
European colonial powers (e.g., UK, France):
Historically core regions that built wealth through exploitation of colonies.
Status (Still Used?):
Yes, in academic settings.
Influences geopolitical studies, global trade analysis, and development theory, though sometimes critiqued for being too rigid.
Globalization Theories
Type: Theories (various)
Developed: 1980s–present
Purpose: Explain the increasing interconnectedness of the world through trade, communication, migration, and culture.
Major Globalization Theories
a. World Systems Theory
(Immanuel Wallerstein, 1970s)
See previous notes — applies here as a globalization theory.
Application: Explains how global capitalism creates and maintains inequality.
Example: China’s rise as semi-periphery due to integration into global markets.
b. Neoliberalism & Free Market Globalization
Key proponents: Milton Friedman, World Bank, IMF
Advocates for open markets, deregulation, and free trade.
Application: NAFTA (1994) and WTO policies promoting global trade.
Example: Mexico industrialized under NAFTA but became dependent on U.S. investment.
c. Cultural Globalization
(Theorists like Arjun Appadurai)
Focuses on global flows of media, migration, and identity.
Application: Global spread of brands, languages, and pop culture.
Example: K-pop’s global popularity (South Korea’s soft power strategy).
Key Vocabulary & Why It Fits:
Time-space compression – Technology shrinks time and distance in interactions.
Global village – Interconnected global culture.
Neoliberalism – Policy foundation of economic globalization.
Homogenization vs. hybridization – Explains cultural blending or loss.
Still Used?
Yes. Central to modern economic, cultural, and political analysis.
Demographic Transition Model (DTM)
Type: Model
Creator: Warren Thompson (1929), later expanded by demographers
Purpose: Explains population changes over time in relation to economic development.
Five Stages:
High birth + high death = stable pop (pre-industrial)
High birth + declining death = pop growth (early industrial)
Declining birth + low death = slowing growth
Low birth + low death = stable pop (post-industrial)
(Optional) Very low birth < death = pop decline (seen in some advanced countries)
Key Vocabulary & Why It Fits:
Birth rate / Death rate – Primary indicators of population change.
Natural increase rate (NIR) – Difference between birth and death rates.
Industrialization – Drives the transition.
Population momentum – Growth continues even as birth rates fall.
Applications in Real Countries:
Stage 2: Nigeria – Rapid growth, high birth rate, improving medicine.
Stage 3: Mexico – Birth rates declining due to urbanization & education.
Stage 4: U.S., France – Stable populations, aging demographics.
Stage 5: Japan, Germany, Italy – Shrinking populations, policy concerns.
Still Used?
Yes, widely used in geography and demography, though criticized for being Eurocentric and not universally applicable.
Galactic City Model (Peripheral Model)
Type: Urban Model
Creator: Chauncy Harris (1960s)
Developed: 1960s (based on observations of post-industrial American cities)
Purpose: Explains how cities in developed countries spread outward in a decentralized, car-based way, creating “edge cities” around a central urban core.
Key Concepts:
Cities no longer centered only on a CBD (Central Business District).
Suburban areas grow independent of downtowns (edge cities).
Shopping malls, industrial parks, and office complexes spring up on the periphery.
Based on car ownership and highway infrastructure.
Key Vocabulary & Why It Fits
Edge cities – Major centers of business, shopping, and entertainment outside traditional downtowns.
Urban sprawl – Cities spread out into formerly rural land.
Decentralization – Movement of people and businesses away from city centers.
Beltway / ring road – Highways that circle cities and connect suburbs.
Applications in Real Places:
Washington, D.C. metro area – Tyson’s Corner, Virginia is a classic edge city.
Atlanta, Georgia – Huge sprawl with multiple edge cities along beltways.
Los Angeles – Extremely decentralized city model.
Still Used?
Yes, especially in U.S. cities.
Explains modern urban form in North America and parts of Australia and Canada.
Migration Models
a. Ravenstein’s Laws of Migration (1885–1889)
Type: Theory/Empirical Generalization
Creator: Ernst Ravenstein (English geographer)
Purpose: Identified patterns of human migration based on census data.
Key Laws:
Most migrants move short distances.
Migration occurs in steps (step migration).
Long-distance migrants often head to urban areas.
Most migration is rural to urban.
Young adults are more likely to migrate.
Every migration flow has a counter-flow.
Applications in Countries:
19th-century Europe to U.S. – Long-distance migration to urban centers.
Rural to urban migration in India, China, Brazil.
U.S. internal migration (Great Migration 1916–1970) – African Americans moved from rural South to urban North.
b. Lee’s Push-Pull Theory (1966)
Type: Theory
Creator: Everett S. Lee
Purpose: Explains migration as a result of push factors (leaving) and pull factors (attracting)
Key Concepts:
Push factors: Poverty, war, unemployment, natural disaster
Pull factors: Jobs, safety, education, better quality of life
Intervening obstacles: Legal, geographic, or cultural barriers that may block migration.
Applications:
Syrian refugee crisis (2010s): Push: war. Pull: safety in Europe.
Mexican migration to U.S.: Economic opportunity = pull; violence = push.
Philippine overseas workers (OFWs): Economic pull from jobs abroad
Key Vocabulary & Why It Fits:
Push/Pull factors – Core of Lee’s model.
Step migration – Matches real migration patterns.
Chain migration – Family members follow first movers; builds communities abroad.
Intervening obstacles – Real-life legal or physical issues (e.g., immigration policy).
Still Used?
Yes. Both models still inform modern migration research and policy planning.
Malthusian Theory (Malthus’ Theory of Population)
Type: Theory
Creator: Thomas Robert Malthus (1798)
Published: An Essay on the Principle of Population (1798)
Purpose: Warned that population growth would outpace food production, leading to famine, war, and societal collapse.
Key Concepts:
Population grows exponentially (doubling) while food supply grows arithmetically (linear).
Believed population checks like famine, disease, and war would naturally reduce population.
Anti-optimistic about human innovation solving the problem.
Key Vocabulary & Why It Fits:
Carrying capacity – Earth’s ability to sustain human life.
Positive checks – Increase death rate (famine, disease, war).
Preventive checks – Decrease birth rate (moral restraint, delayed marriage).
Overpopulation – Core fear of the theory.
Applications in Real Places:
19th-century England: Concern about industrial-era urban crowding.
Modern relevance:
Worries about food security in Sub-Saharan Africa and South Asia.
Used by neo-Malthusians warning about resource scarcity (e.g., climate change impacts).
Still Used?
Partially.
While Malthus’ predictions didn’t fully happen (due to agricultural innovation like the Green Revolution), fears about resource limits and overpopulation still invoke neo-Malthusian ideas today.
Bid Rent Theory (Land Rent Theory)
Type: Urban Economic Model
Creator: William Alonso (1960s) — based on earlier work by Johann von Thünen
Purpose: Explains how land value and land use change as you move farther from the city center.
Key Concepts:
Land near the CBD is most expensive because businesses want maximum access to customers.
Different users (commercial, industrial, residential) are willing to pay different amounts (bids) for land.
Explains why skyscrapers cluster downtown and suburbs are lower density.
Key Vocabulary & Why It Fits:
Bid rent curve – Graph showing declining land prices with distance from CBD.
Central Business District (CBD) – High-value commercial core of the city.
Distance decay – Decreased interaction and land value farther from the center.
Zoning – Land use is separated based on willingness to pay.
Applications in Real Places:
New York City:
Midtown and Downtown Manhattan have extremely high land costs for businesses.
London:
Central London has the most expensive real estate; outer boroughs are more residential.
Chicago:
Classic concentric zone patterns reflecting bid rent theory.
Still Used
Yes.
Important in urban planning, real estate, geography, and understanding urban land use patterns even today.
Rimland Theory
Type: Geopolitical Theory
Creator: Nicholas Spykman
Developed: 1942 (The Geography of the Peace)
Purpose: Counters Mackinder’s Heartland Theory; argues that the coastal fringes (rimland) of Eurasia are key to global power.
Key Concepts:
Who controls the Rimland controls Eurasia, and therefore the world.
Emphasizes the importance of sea access, trade, and military/naval power.
Rimland = Europe + Middle East + South Asia + Southeast Asia + East Asia
Key Vocabulary & Why It Fits:
Geopolitics – Study of how geography shapes political power.
Rimland – Strategic coastal zones of Eurasia.
Containment – U.S. Cold War policy rooted in this theory (to limit Soviet expansion in rimland areas).
Buffer zone – Strategic regions that prevent domination by a single power.
Applications in Real Places:
Cold War Era:
U.S. focused military and political efforts on Europe, Korea, Vietnam, Middle East, etc.
Modern Examples:
U.S. and China competition in the South China Sea, Taiwan, and Indo-Pacific reflects Rimland thinking.
Still Used?
Yes.
Especially in military strategy, foreign policy, and modern geopolitical analysis (e.g., NATO and Indo-Pacific strategies).
Least Cost Theory
Type: Economic/Industrial Location Theory
Creator: Alfred Weber
Developed: 1909
Purpose: Explains where industries choose to locate based on minimizing costs.
Key Concepts:
Industry location is based on minimizing:
Transportation costs
Labor costs
Agglomeration effects (benefits of clustering industries together)
Similar to von Thünen’s ideas but for industrial location instead of agriculture.
Key Vocabulary & Why It Fits:
Bulk-reducing industry – Product weighs less than inputs (locate near raw materials).
Bulk-gaining industry – Product gains weight (locate near markets).
Agglomeration – Clustering of related businesses to reduce costs and increase efficiency.
Deglomeration – When industries spread out due to overcrowding or high land costs.
Applications in Real Places:
Steel industry in Pittsburgh:
Located near coal and iron (bulk-reducing).
Auto industry in Detroit:
Agglomeration of suppliers, manufacturers, labor.
Modern factories in Mexico (e.g., maquiladoras):
Lower labor costs, close to U.S. markets = ideal location.
Still Used?
Yes.
It’s a foundational model for industrial geography and still applies to manufacturing, though updated with factors like globalization, automation, and digital infrastructure.
Bid Rent Curve
Type: Economic Model (Urban Geography)
Creator: William Alonso (1960s) — based on von Thünen’s agricultural model
Purpose: Shows how land value (rent) changes with distance from the CBD and explains urban land use patterns.
Key Concepts
Land closest to the Central Business District (CBD) is most expensive.
Different types of land users (commercial, industrial, residential) have different willingness to pay based on how much accessibility they need.
Businesses (especially retail) need high access → pay the most → locate centrally.
Residents need space → pay less → live further from the center.
Key Vocabulary & Why It Fits
Bid rent – The maximum amount a user is willing to pay for land at a given location.
Distance decay – Value and demand decrease with distance from the center.
Accessibility – Determines land value; more access = higher rent.
Zoning – Laws that separate urban land uses (residential, commercial, industrial).
Applications in Real Places:
New York City:
Manhattan’s midtown/downtown = high bid rent for businesses.
Residential areas in Queens or Staten Island = lower rent.
London:
High commercial rent in Central London; lower residential rent in suburbs.
Tokyo:
Core is dominated by high-paying business districts, residents live further out.
Still Used?
Yes.
Widely used in urban planning, real estate, and transportation geography.
Ravenstein’s Laws of Migration
Type: Migration Theory
Creator: Ernst Georg Ravenstein
Developed: 1885–1889 (based on British census data)
Purpose: Identified patterns of human migration that still hold true today.
Key Concepts:
Most migrants move short distances (step migration).
Long-distance migrants tend to go to economic centers (big cities).
Urban residents are less migratory than rural ones.
Young adults are more likely to migrate than families or elderly.
Migration flow often creates a counter-flow.
Economic motives are the primary driver.
Key Vocabulary & Why It Fits:
Step migration – Migration in stages (e.g., village → town → city).
Chain migration – Following relatives/friends to a location.
Counter migration – Movement in the opposite direction of a main flow.
Push-pull factors – Conditions that drive people away or attract them.
Applications in Real Places:
19th–20th century Europe → U.S. migration (long-distance economic migration).
U.S. Great Migration (1916–1970):
African Americans moved from the rural South to urban North.
Modern internal migration in China:
Millions move from countryside to urban industrial zones.
Still Used?
Yes.
Forms the foundation of migration theory, often built upon with models like Lee’s push-pull theory.
Urban Realms Model
Type: Urban Spatial Model
Creators: James E. Vance Jr.
Developed: 1964
Purpose: Describes how modern, decentralized cities work, especially in the U.S. with sprawling suburbs.
Key Concepts:
A city is made up of “urban realms” — self-sufficient areas with their own CBDs, jobs, and suburbs.
Each realm is independent but connected to the larger metro area.
Reflects the rise of the edge city, highways, and car dependence.
Key Vocabulary & Why It Fits:
Urban realm – A semi-independent suburban region within a larger city.
Edge city – Commercial hub on the outskirts of a city.
Polycentric – Cities with multiple centers of activity.
Suburbanization – Expansion of population and economy to the outskirts.
Applications in Real Places:
San Francisco Bay Area:
San Francisco, Oakland, San Jose, and surrounding suburbs each have their own functions.
Los Angeles:
Decentralized, polycentric urban area with multiple realms.
Houston and Dallas:
Suburban business centers and ring-road highways reflect the model.
Still Used?
Yes.
Especially useful in understanding post-industrial North American cities with complex metro regions.
Heartland Theory
Type: Geopolitical Theory
Creator: Halford Mackinder
Developed: 1904 (The Geographical Pivot of History)
Purpose: Argues that control over the central landmass of Eurasia (the “Heartland”) is key to global dominance.
Key Concepts:
“Who rules East Europe commands the Heartland;
Who rules the Heartland commands the World Island;
Who rules the World Island commands the World.”The Heartland includes central and eastern Europe, Russia, and Central Asia.
Land power was seen as more important than sea power.
Based on the belief that railroads would make inland power more significant.
Key Vocabulary & Why It Fits:
Geopolitics – How geography influences politics and power.
Heartland – Interior Eurasian landmass; hard to invade, resource-rich.
World Island – Eurasia + Africa; majority of population and resources.
Land power – Dominance through control of land and armies rather than navies.
Applications in Real Places:
Used to justify Western fears of Soviet expansion during the Cold War.
Influenced NATO and containment strategies in Eastern Europe.
Modern geopolitical concerns about Russia’s influence in Central Asia and Ukraine still reflect Heartland ideas.
Still Used?
Yes, in part.
While outdated as a complete model, it still shapes military strategy and geopolitical thinking.
Organic Theory
Type: Political Geography Theory
Creator: Friedrich Ratzel (Germany)
Developed: 1897
Purpose: Compares a state to a living organism — it needs to grow and expand to survive.
Key Concepts:
A state is like a biological organism with a life cycle.
Needs territorial expansion (Lebensraum) to maintain strength.
Borders are temporary; political power must grow or die.
Justified imperialism and military expansion in early 1900s.
Key Vocabulary & Why It Fits:
Lebensraum – “Living space”; concept used to justify territorial expansion.
Nation-state – A state with cultural unity, treated like an organism.
Territoriality – A state’s desire to control land and resources.
Expansionism – The policy of increasing a nation’s power through territory.
Applications in Real Places:
Nazi Germany used it to justify invasions (e.g., Poland, USSR).
Influenced early 20th-century imperial powers.
Reflected in Russian expansionism in Eastern Europe (Cold War & present day).
Still Used?
Not as a formal model anymore due to its association with fascist ideologies, but its core ideas reappear in nationalist and imperialist rhetoric.
Neo-Malthusians
Type: Modern Population Theory
Origin: Evolved from Thomas Malthus’s 1798 ideas, gained traction in mid-1900s to present
Purpose: Warn that unchecked population growth still threatens resources, but includes technology and environment in the equation.
Key Concepts
Emphasize environmental degradation, not just food supply.
Warn of resource scarcity: water, oil, land, etc.
Focus on the carrying capacity of Earth and sustainability.
Concerned with rapid growth in developing nations and impact on climate change.
Key Vocabulary & Why It Fits:
Carrying capacity – Maximum population Earth can sustain.
Overpopulation – When population exceeds resource availability.
Resource depletion – Using resources faster than they can regenerate.
Sustainability – Meeting current needs without harming future generations.
Applications in Real Places:
India and China’s population policies (e.g., China’s One Child Policy) drew on Neo-Malthusian concerns.
Global environmental movements focus on consumption and birth rates.
Warnings from Paul Ehrlich (The Population Bomb, 1968) and groups like Club of Rome.
Still Used
Yes.
Central to climate change, environmental, and population planning discussions today.
Epidemiological Transition Model
Type: Population Health Model
Creator: Abdel Omran
Developed: 1971 (The Epidemiologic Transition Theory)
Purpose: Explains how patterns of disease and causes of death shift as societies develop.
Key Concepts:
Health and disease evolve in predictable stages as countries industrialize.
Early stages = infectious diseases dominate (e.g., plague, cholera).
Later stages = chronic and degenerative diseases dominate (e.g., cancer, heart disease).
Follows similar stages as the Demographic Transition Model.
Key Vocabulary & Why It Fits:
Pandemic – Widespread disease outbreak.
Degenerative diseases – Long-term diseases like heart disease and diabetes.
Epidemiology – Study of disease patterns and causes.
Transition – Shift from infectious to chronic diseases.
Applications in Real Places:
Pre-Industrial Europe: Black Death, smallpox dominate.
Industrial England (1800s): Sanitation reduces infectious diseases.
Modern U.S./Japan: Death mostly from cancer, heart disease, not infectious diseases.
Still Used?
Yes.
Still crucial in public health planning, global health, and development studies.
Modernization Theory / Dependency Theory
A. Modernization Theory
Type: Economic Development Theory
Creators: Walt Rostow (with others in 1950s–60s)
Developed: 1950s (during Cold War)
Purpose: Describes how societies move from traditional to modern industrial economies.
Key Concepts:
Development is linear: all countries can progress through 5 stages (traditional society → high mass consumption).
Emphasis on internal changes: education, technology, investment, etc.
Key Vocabulary & Why It Fits:
Traditional society – Pre-industrial, agricultural-based economy.
Take-off – Key moment of rapid industrial growth.
Mass consumption – High-income consumer society.
Westernization – Adoption of Western values and systems.
Applications in Real Places:
South Korea: Applied modernization after Korean War → rapid industrial growth.
Singapore and Taiwan: Modeled development on Western-style economies.
Still Used?
Partially.
Criticized for being Eurocentric, but still influences global development policies.
B. Dependency Theory
Type: Critical Development Theory
Creators: Andre Gunder Frank (1960s) and others
Purpose: Critiques Modernization Theory; argues that developing countries are kept poor by global capitalist exploitation.
Key Concepts:
Rich “core” nations exploit poor “periphery” nations.
Development of the core = underdevelopment of the periphery.
Focus on external causes of poverty (colonialism, neocolonialism).
Key Vocabulary & Why It Fits:
Core-periphery – Rich vs. poor division of the world.
Neocolonialism – Economic control replacing direct political rule.
World-systems – Global economic and political interconnection.
Exploitation – Taking resources from one place for benefit of another.
Applications in Real Places:
Latin America (1960s–70s): Economists saw dependency patterns with U.S. and Europe.
Africa: Post-colonial economies struggled under dependency patterns (resource extraction for export).
Still Used?
Yes.
Very influential in globalization studies, economic inequality, and development critiques.
Rank-Size Rule
Type: Urban Geography Model
Creator: G.K. Zipf (1940s)
Purpose: Predicts how city sizes are distributed within a country.
Key Concepts:
The nth largest city in a country is 1/n the size of the largest city.
Example: 2nd largest city is half the size of the largest; 3rd is one-third, and so on.
Suggests balanced urban systems with no extreme primate city.
Key Vocabulary & Why It Fits:
Urban hierarchy – Ranking of cities by size and function.
Primate city – Exception to rank-size rule (one giant city dominating).
Central place theory – Explains distribution of cities and services.
Disproportionate growth – When one city grows much faster than expected.
Applications in Real Places:
United States:
New York, Los Angeles, Chicago, Houston roughly fit rank-size distribution.
Germany:
Balanced distribution: Berlin, Hamburg, Munich, Cologne follow the pattern.
France (counter-example):
Paris is so dominant that rank-size rule does not apply (primate city).
Still Used?
Yes.
Still referenced in urban planning, economic geography, and city size studies.