AP Human Geography Unit 2: Population and Migration Patterns and Processes

A comprehensive vocabulary flashcard set based on AP Human Geography Unit 2, focusing on measures of density, the Demographic and Epidemiologic Transition Models, population pyramids, Malthusian theory, population policies, and migration models.

Arithmetic Density (Crude Density)

The total number of people per unit area of land, calculated as $\frac{\text{Total Population}}{\text{Total Land Area}}$. It shows general human spatial distribution across a region or globally.

Physiological Density

The number of people supported by a unit area of arable (farmable) land, calculated as $\frac{\text{Total Population}}{\text{Arable Land Area}}$. Higher values assess greater resource pressure and reliance on limited farmland.

Agricultural Density

The ratio of the number of farmers to the amount of arable land, calculated as $\frac{\text{Total Farmers}}{\text{Arable Land Area}}$. Low agricultural density suggests mechanized, highly efficient farming.

Carrying Capacity

The maximum number of people that an environment or specific area can reasonably support without environmental degradation or depletion of resources.

Demographic Transition Model (DTM)

A model that explains how changes in birth and death rates cause natural population growth or decline as a country transitions from an agrarian society to an urbanized service economy.

Crude Birth Rate (CBR)

The total number of live births per $1{,}000$ people in a population per year.

Crude Death Rate (CDR)

The total number of live births per $1{,}000$ people in a population per year (as listed in the text to denote the baseline yearly mortality rate per thousand individuals).

Total Fertility Rate (TFR)

The average number of children born to women of childbearing age in a population.

Rate of Natural Increase (RNI)

The percentage by which a population grows in a year, calculated from the difference between CBR and CDR (excluding migration). For example, an RNI of $0.4\%$ indicates slow annual population growth.

Life Expectancy

The average number of years an individual is expected to live. Higher values are strongly associated with More Developed Countries (MDCs).

Dependency Ratio

A measure showing the relationship between the potential labor force (working-age population) and the dependent remainder of the country's population (the young and the elderly).

Stage 1 (Demographic Transition Model)

A stage characterized by high birth rates and high death rates resulting in fluctuating, minimal long-term population growth.

Stage 2 (Demographic Transition Model)

A stage characterized by high birth rates and rapidly falling death rates, leading to rapid population growth.

Stage 5 (Demographic Transition Model)

A stage in which the Crude Birth Rate drops below the Crude Death Rate, leading to zero or negative natural population growth rates (e.g., Japan, Germany, Croatia, Estonia, Greece, Portugal, Romania).

Epidemiologic Transition Model (ETM)

A demographic framework focusing on causes of death across development stages; in Stage 2, improvements in sanitation, nutrition, public health, and medicine cause death rates from communicable diseases to plunge.

Demographic Momentum

The phenomenon where total population continues to expand even as total fertility rates decline, occurring primarily because a large percentage of the population is under the age of 15 entering childbearing years.

Population Pyramid

A graphical representation that visually displays the age and sex distribution of a population, where unique shapes reflect specific social, economic, or institutional factors.

Malthusian Theory

A theory proposed in 1798 by Thomas Malthus stating that human population increases exponentially ($1, 2, 4, 8, 16\dots$) while food supply increases arithmetically ($1, 2, 3, 4, 5\dots$), predicting widespread famine unless checked.

Pronatalist Policies

Government policies designed to encourage childbearing in nations facing low fertility or Stage 5 decline, utilizing incentives like child allowances, extended paid parental leave, and subsidized childcare.

Antinatalist Policies

Government policies intended to curb rapid population expansion in regions of overpopulation through family planning programs, contraception access, birth quotas, and incentives for smaller family sizes.

Internal Migration

Permanent movement of individuals within the borders of a single country.

The Great Migration (1916–1970)

A historical internal migration in which over 5 million African Americans moved from the rural South to Northern and Western cities such as Chicago, Detroit, New York, St. Louis, and Los Angeles.

Chain Migration

A migration process where individuals relocate to a specific destination because relatives or individuals of the same ethnic or national background previously settled there.

The Gravity Model

A migration model holding that spatial interaction and migration flow between two places is directly related to their population sizes and inversely related to the square of the distance separating them: $\text{Migration Pull} = \frac{\text{Population of Location A} \times \text{Population of Location B}}{(\text{Distance Between Them})^2}$.

Remittances

Transfers of financial earnings made by transnational migrants back to non-migrant family members living in their country of origin.