AP Human geography unit 2 notes

AP Human Geography Unit 2: Population and Migration

Key Concepts

1. Population Distribution

• Population Density: Measure of people per unit area (e.g., per square mile).

  • Arithmetic Density: Total population divided by total land area.

  • Physiological Density: Population divided by arable land area.

  • Agricultural Density: Number of farmers per unit of arable land.

2. Population Growth

• Natural Increase Rate (NIR): Difference between birth rate and death rate.

• Crude Birth Rate (CBR): Number of live births per 1,000 people.

• Crude Death Rate (CDR): Number of deaths per 1,000 people.

• Total Fertility Rate (TFR): Average number of children a woman will have during her lifetime.

3. Demographic Transition Model (DTM)

• Stages:

  • Stage 1: High birth and death rates; low NIR.

  • Stage 2: High birth rates; declining death rates; rapid NIR.

  • Stage 3: Declining birth rates; low death rates; moderate NIR.

  • Stage 4: Low birth and death rates; stable NIR.

  • Stage 5: Potential decline in population; very low birth rates.

4. Migration

• Types of Migration:

  • Internal Migration: Movement within a country.

  • International Migration: Movement across country borders.

  • Voluntary Migration: Choice to move (e.g., for better opportunities).

  • Involuntary Migration: Forced movement (e.g., refugees).

5. Push and Pull Factors

• Push Factors: Conditions that drive people away (e.g., war, famine).

• Pull Factors: Conditions that attract people (e.g., jobs, safety).

6. Migration Patterns

• Ravenstein's Laws of Migration:

  • Most migrants move short distances.

  • Migration occurs in steps (step migration).

  • Urban areas attract more migrants than rural areas.

  • Families are less likely to make international moves than young adults.

7. Population Policies

• Pro-natalist Policies: Encourage higher birth rates (e.g., financial