AP Human Geography Key Concepts

Unit 1: Latitude vs Longitude

• Latitude: Based on the equator, horizontal.
• Longitude: Based on the prime meridian, vertical.

GIS

• Used to layer different maps to show patterns in data.

Thematic Maps

• Type of map that shows data with a theme.
  • Examples: Isoline, Dot, Choropleth

Unit 2: Population Pyramids

• Used to show demographic patterns in a population using sex and age.

DTM (Demographic Transition Model)

• 5 stages that countries go through, categorized by birth/death rates and natural population increase.
• Does not factor in migration.
• More developed countries = later stages of the model.

Epidemiological Transition Theory

• Connected to DTM; shows the types of diseases a country is likely to face based on its development stage.
  • Stage one: Cholera (underdeveloped country, poor sanitation).
  • Stage five: Alzheimer's (developed country, good healthcare, long life expectancy).

Ravenstein's Laws of Migration

• Common patterns that migrants share:
  • Most move a short distance.
  • Migration goes by steps.
  • Long-distance migrants are more likely to move to big cities.
  • All migration flows have a counterflow.
  • People of rural areas are more likely to migrate.
  • Men are more likely to migrate long distances, while women are more likely to migrate short distances.
  • Migrants are mostly adults, not families.
  • Urban areas mostly grow from in-migration, not naturally.
  • Migration increases with more transportation and economic opportunities.
  • Mostly from rural to urban areas.
  • Economic factors are the main cause of migration.

Zelinsky Model of Migration Transition

• Describes the type of migration likely to happen depending on a country's demographic stage.
  • Stage two: rural to urban migration.
  • Stage five: urban to suburban migration.

Malthusian Theory of Population Growth

• 18th-century idea that the world's population grows exponentially while food production grows linearly.
• Not enough food is available to sustain the population, leading to "checks" (famine, war).
• Inaccurate due to technological advancements leading to increased food production.

Unit 3: S-Curve

• Shows the speed at which ideas are adopted.
  • Starts slowly, becomes popular, then cools off.

Language Tree

• Tree showing which languages came from which language family.
• Indo-European is the largest language family (European and Indo-Iranian languages).

Unit 4: Organic Theory

• Inspired by Hitler, the idea that countries are like living organisms.
• Countries go through birth and death and need "nourishment" (acquiring less powerful states).
• Without expansion, the state would die.

Mackinder's Heartland Theory

• The key to achieving global power is to conquer Eastern Europe/Russia.

Spyman's Rimland Theory

• Key to global power is conquering the UK, India, and China.

Domino Theory

• During the Cold War: if one country "fell" to Communism, surrounding countries would also fall.

Core-Periphery Model

• Describes the relationship between core and periphery countries.
• The core relies on labor from periphery countries.

Unit 5: Von Thunen Model

• Shows where industries are located around a city:
  • First ring: dairy farming and market gardening.
  • Second ring: forests.
  • Third ring: grains and field crops.
  • Fourth ring: ranching and livestock.

Ester Boserup's Theory

• Food production will increase based on population increase.

Unit 6: Rostow's Stages of Development

• Country industries develop in 5 stages over time:
  • Stage one: Traditional Society.
  • Stage two: Preconditions to take off.
  • Stage three: Take off.
  • Stage four: Drive to maturity.
  • Stage five: High mass consumption.

Wallerstein's World System Theory

• Connection between core-periphery relationships and industrial development.
  • Core countries sell high-profit goods to periphery/semi-periphery countries.
  • Periphery/semi-periphery countries provide raw materials and labor.

Dependency Theory

• World Systems Theory's dependency was caused by colonization.
• Periphery countries' production was replaced by labor, which helped core countries develop goods; they became dependent on core countries for food and consumer goods.

Unit 7: Weber's Least Cost Theory

• Industries locate where transportation costs of raw materials and finished products are lowest.
  • Raw materials heavier than the finished product: the factory is closer to the materials.
  • Finished products are more costly to transport than materials: industry is closer to the market.

Christaller's Central Place Theory

• Based on how far people are willing to travel for work and products.
• A hexagon shape of main cities is surrounded by small towns and cities.

Burgess Concentric Zone Model

• Describes the layout of a city.
  • The center (business district) is surrounded by rings of industry/residential areas.
  • Wealthy people live furthest from the center to avoid pollution.

Gravity Model

• People are more willing to go to certain places over others.
  • Example: Chicago attracts more people than Detroit.

Hoyt Sector Model

• City map where the lowest class lives around transportation, while the upper class lives along business sectors.

Harris-Ullman Multiple Nuclei Model

• City layout with multiple central business districts.

Borchert's Epochs of Urban Growth

• Evolution of the American Urban System:
  • Cities developed near ports and major waterways.
  • Then along railroads and steamboats.
  • Early 20th century: long-haul railroads.
  • Later: gasoline-powered transportation (cars and planes).
  • Since the 1970s: development around the service and information technology sectors.

Zipf's Rank-Size Rule

• The formula for the $n$th largest city is 1/n of the largest city.
  • Example: The second-largest city is half the size (population) of the largest city.
  • US example: (#1 Los Angeles 3.8 million, #2 Chicago 2.6 million, #3 Houston 2.3 million)

Bid-Rent Curve

• The further away from the central city, the higher the land prices.