Demography and Carrying Capacity Vocabulary

Key terminology and core concepts covering demographic measures, population growth models, Malthusian theory, and carrying capacity from the lecture.

Demographic Equation

An equation used to calculate the population growth rate, expressed as $R = (b - d) + (i - e)$, where $b$ is birth rate, $d$ is death rate, $i$ is immigration rate, and $e$ is emigration rate.

Crude Birth Rate (CBR)

The annual number of live births per $1000$ individuals in a population.

Crude Death Rate (CDR)

The annual number of deaths per $1000$ individuals in a population.

Total Fertility Rate (TFR)

The average number of children a woman would likely have during her childbearing years.

Replacement Fertility Rate

The total fertility rate required to keep a population stable without migration, defined as $2.1$ children per woman to account for infant mortality.

Infant Mortality Rate (IMR)

The annual number of deaths of infants under $1$ year of age per $1000$ live births.

Rate of Natural Increase (RNI)

The percentage or rate of population growth calculated as Crude Birth Rate minus Crude Death Rate ($\text{CBR} - \text{CDR}$).

Doubling Time

The period of time required for a given population to double in size under a constant annual growth rate.

Rule of 70

A mathematical approximation derived from the compound interest equation used to calculate population doubling time as $\text{Doubling Time} \approx 70 \div r$, where $r$ is the annual percentage growth rate.

Malthusian Catastrophe

The predicted point where exponential population growth overtakes linear subsistence growth, resulting in a sudden corrective decline in population.

Preventive Checks

Demographic checks identified by Thomas Malthus that reduce birth rates, including delayed marriage and moral restraint.

Positive Checks

Demographic checks identified by Thomas Malthus that increase death rates to correct population imbalance, such as famine, disease, and war.

Malthusian Trap

A state where population growth repeatedly pulls living standards back down to subsistence levels following periods of growth.

Carrying Capacity

The maximum population of a biological species that a given habitat or environment can sustain and support over time.

Biophysical Carrying Capacity

The maximum population capacity set directly by ecological limits such as food, water, energy, and waste absorption capability.

Social Carrying Capacity

The effective population capacity supported by how a society organizes, distributes, trades, and cooperates around existing natural resources.

Ecological Deficit

A condition occurring when the environmental load imposed by a human population exceeds the productive biological capacity of its territory.

Overshoot

A state where a population temporarily exceeds available environmental carrying capacity, risking long-term habitat impairment and eventual population crash.

Population Momentum

The continued expansion of a population even after fertility rates fall to replacement levels, caused by a high proportion of young people entering childbearing years.

Population Pyramid

A bar graph diagram that illustrates the age and gender distribution of a population.

Working Age Population

The cohort in a population pyramid (typically ages 15 to 64) that is capable of working to sustain youth and elderly dependent groups.

The Population Bomb

A 1968 neo-Malthusian book written by Dr. Paul R. Ehrlich warning that population growth would lead to widespread global starvation.

Logistic Growth Curve

An S-shaped growth curve formed when population growth rate slows as carrying capacity is approached, reaching a stable equilibrium.