Populations and Urbanization

Vocabulary review flashcards covering population ecology, human demographics, age structure, demographic transitions, and urban planning terms.

Logistic Growth

Population growth that levels off as the population size approaches the carrying capacity of the environment, producing an S-shaped curve.

Carrying Capacity (K)

The maximum population size of a biological species that a particular environment can sustain indefinitely given the available food, habitat, water, and other necessities.

Exponential Growth

Unrestricted population growth that increases at a constant proportional rate per unit of time, producing a J-shaped curve when resources are unlimited.

Limiting Factors/Resources

Physical or biological factors, such as food, water, space, or predation, that restrict the growth, abundance, or distribution of a population.

S-shaped Curve (sigmoid curve)

A graphical representation of logistic population growth that shows an initial lag phase, followed by rapid exponential growth, and finally stabilization at carrying capacity.

J-shaped Curve

A graphical curve illustrating exponential population growth where numbers increase progressively faster over time without immediate resource limitation.

Intrinsic Rate of Increase (r)

The theoretical maximum rate at which a population can grow under optimal conditions with unlimited resources.

Biotic Potential

The maximum capacity of an organism or population to reproduce and survive under ideal environmental conditions.

Population Overshoot

The condition occurring when a population exceeds the environmental carrying capacity, often depleting critical resources.

Population Dieback

A sudden and steep decline or crash in population size that follows an overshoot when resources become exhausted.

Survivorship Curves

Graphs showing the relative survival rates of a cohort from birth to the maximum life span, classified into Type I (late mortality), Type II (constant mortality), and Type III (early mortality).

R-selected species

Species that emphasize high reproductive rates, producing many offspring with short gestation periods, low parental care, and high early-life mortality.

K-selected species

Species that maintain populations close to carrying capacity, characterized by longer gestation periods, fewer offspring, high parental investment, and high survivorship into adulthood.

Gestation period

The length of time required for embryonic and fetal development from conception until birth in viviparous animals.

Demography

The statistical study of human populations, focusing on size, density, distribution, movement, and vital statistics such as births and deaths.

(Crude) Birth Rate

The number of live births occurring among the population of a given geographical area per $1{,}000$ people in a year.

(Crude) Death Rate

The number of deaths occurring among the population of a given geographical area per $1{,}000$ people in a year.

Doubling Time

The time required for a population to double its size at a constant percentage growth rate, commonly calculated as $\frac{70}{\% \text{ growth rate}}$.

% Growth Rate

The net rate at which a population increases or decreases over a given period, calculated taking into account births, deaths, immigration, and emigration as a percentage.

Emigration

The permanent departure of individuals out of a native or resident population or region to settle elsewhere.

Immigration

The permanent arrival of individuals into a non-native population or region from elsewhere.

GNI

Gross National Income; the total domestic and foreign output claimed by residents of a country, consisting of GDP plus factor incomes earned by foreign residents minus income earned in the domestic economy by nonresidents.

Infant Mortality Rate

The number of infant deaths under one year of age per $1{,}000$ live births in a given year.

Life Expectancy

The average number of years a newborn individual is expected to live if prevailing mortality patterns remain constant throughout their life.

Replacement Level Fertility Rate

The average number of children a couple must have to replace themselves, which is approximately $2.1$ in developed countries.

Total Fertility Rate

The average number of children that would be born to a woman over her lifetime if she were to pass through her childbearing years conforming to current age-specific fertility rates.

Age Structure Graphs

Diagrams that display the distribution of a population across different age cohorts and biological sexes, visually communicating population momentum.

Prereproductive/Reproductive/Postreproductive Ages

The three broad demographic age classes: prereproductive ($0$-$14$), reproductive ($15$-$44$), and postreproductive ($45+$).

Family Planning

Programs and services that provide clinical educational, social, and medical means enabling individuals and couples to control the timing and spacing of their offspring.

Demographic Transition Model

A historical model demonstrating the shift of a country from high birth and death rates to low birth and death rates through economic and industrial development.

Shantytowns/Squatter Settlements

Unplanned, informal settlements of makeshift dwellings constructed on land that the occupants do not legally own or rent, often lacking basic services like clean water and sewage systems.

Heat Island Effect

The microclimatic condition where built urban environments absorb, retain, and radiate heat, resulting in significantly higher temperatures compared to surrounding rural areas.

Urban Sprawl

The uncontrolled, low-density expansion of urban communities over large areas of land, characterized by high automobile dependency.

Megalopolis

An extensive, continuous concentration of urban areas and interconnected metropolitan zones functioning as a unified socioeconomic entity.

Smart Growth

An urban planning strategy that emphasizes compact, transit-oriented, walkable, and environmentally sustainable development to combat sprawl.

Brownfield

Abandoned, idle, or underused industrial and commercial facilities where redevelopment is complicated by real or perceived environmental contamination.

Rapid Transit Systems

High-capacity public passenger transportation systems operating on dedicated grade-separated rights-of-way, such as subways and light rail.

Walking School Buses

A supervised, group-based alternative form of student transportation where children walk to school along defined routes accompanied by adult volunteers.

Conservation Easements

Legally binding voluntary agreements between a landowner and a land trust or government agency that permanently restrict development on private land to protect its ecological value.

Greenbelt

A policy or physical zone of preserved open space, agricultural land, or forest surrounding an urban perimeter to restrict outward urban expansion.

Greenways

Corridors of undeveloped, vegetated land conserved for recreational use, non-motorized transport, and wildlife movement within developed areas.

LEED

Leadership in Energy and Environmental Design; a globally recognized green building certification program rating the sustainability and efficiency of structures.

Vertical construction

The practice of constructing multi-story high-rise buildings rather than single-story structures to maximize land use efficiency and reduce the overall physical footprint.

PRT

Personal Rapid Transit; an automated public transit system using small, driverless vehicles operating on dedicated exclusive networks of guideways on demand.

Mixed-use development

A type of urban planning that blends residential, commercial, cultural, institutional, or entertainment uses into single structures or integrated pedestrian-friendly zones.

MAGLEV

Magnetic Levitation; high-speed train technology that uses electromagnetic systems to suspend, guide, and propel vehicles above a track without physical contact.