In-Depth Notes on Population and Migration Patterns

Unit 2: Population and Migration Patterns and Processes

AP Human Geography (2021)

Big Idea Questions

  • Impact of Living Conditions: How does where and how people live impact global cultural, political, and economic patterns?

  • Influential Factors on Population Changes: How does the interplay of environmental, cultural, political, and economic factors influence changes in population?

  • Effects of Population Changes: How do changes in population affect a place’s economy, culture, and politics?

Essential Vocabulary

  • Agricultural Density: Measure of the number of farmers per unit of arable land.

  • Arithmetic Density: The total number of people divided by the total land area.

  • Brain Drain: The emigration of highly trained or qualified people from a particular country.

  • Carrying Capacity: The maximum number of individuals that an environment can support.

  • Census: An official count or survey of a population.

  • Dependency Ratio: The ratio of dependents (people typically not in the labor force) to working-age people in a population.

  • Doubling Time: The period of time required for a quantity to double in size or value.

  • Ecumene: The portion of Earth's surface occupied by permanent human settlements.

  • Infant Mortality Rate (IMR): The number of deaths of infants under one year old per 1,000 live births.

  • Urbanization: The increasing number of people that live in urban areas.

Population Distribution

Objectives:

  1. Identify the factors that influence the distribution of human populations at different scales.

  2. Define methods geographers use to calculate population density.

  3. Explain the different impacts of these methods on understanding population.

Where Do Humans Live?

  • World Population (2020): 7.7 billion

    • Africa: 1.2 billion

    • Asia: 4.4 billion

    • Oceania: 42.5 million

    • Europe: 747.4 million

    • North America: 579 million

    • South America: 422.5 million

  • Most large populations are located in tropical climates, usually centered around ancient agricultural hearths where conditions for food cultivation were optimal.

Fresh Water Distribution

  • 70% of the Earth is covered in water; however, only 2.5% is fresh water, and most of that is in glaciers and polar ice.

  • Less than 1% of available fresh water is easily accessible, leading to population centers developing around these sources.

Density Measurements

  • Arithmetic Density: Number of people per total land area.

  • Physiological Density: Number of people supported by arable land.

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

Example Case: Egypt

  • Egypt has a low arithmetic density due to the Sahara Desert but a high physiological density near the Nile River where arable land exists.

  • More developed countries tend to have lower agricultural density due to technological efficiency.

Consequences of Population Distribution

Objectives:

  1. Explain how population distribution and density affect society and the environment.

Carrying Capacity and Overpopulation

  • Carrying Capacity: Refers to the amount of resources the Earth can provide per person.

  • Overpopulation: Occurs when the number of people exceeds Earth's carrying capacity, leading to resource strain.

The Demographic Transition Model (DTM)

Objectives:

  1. Explain theories of population growth and decline.

  2. Explain how women's changing roles influence demographic changes.

Stages of Population Growth

  • Modern Age: Higher education and improved medical practices contribute to lower birth rates and mortality rates.

  • Industrial Revolution: Improved agricultural technology reduces the mortality rate (germ theory, vaccinations).

Significant Trends and Effects

  • As education and career opportunities increase for women, birth rates tend to decrease as child-rearing shifts from an asset to a financial burden due to the cost of raising children.

Malthusian Theory

  • 1798: Thomas Robert Malthus predicted population growth would outpace food production, leading to famine. While this theory had valid points historically, advancements in food supply and preservation have generally negated Malthus's predictions in developed nations.

Population Policies

Pro-Natalist Policies

  • Encouragement of Birth Rates: Policies that promote higher birth rates through incentives for families, often seen in countries with declining birth rates.

Anti-Natalist Policies

  • Control Over Population Growth: Incentives to reduce birth rates, as seen in China's One Child Policy, which has created demographic imbalances.

Migration Dynamics

Objectives:

  • Explain migration types and their effects.

Key Concepts

  • Emigration vs. Immigration:

    • Emigration: Leaving one's country.

    • Immigration: Coming into a new country.

  • Push/Pull Factors: Drive individuals to migrate based on cultural, economic, environmental, and political factors.

  • Ravenstein's Laws of Migration: Most migration is for economic reasons, tends to be short-distance, and rural to urban.

Effects of Migration

  • Urbanization impacts population pyramids, often leveling it out and spreading cultural diversity through the relocation of people.

Aging Populations

  • Implications of aging populations include economic strain due to a high dependency ratio and shifts in political voting patterns.

These notes provide essential insights into human population distribution, implications of migration, and demographic policies that shape global societal patterns today.