AP HuG 2.1-2.4

Emigration

leaving an area as part of a permanent move (in common language, this word has blended into immigration which includes both)

Environmental degradation

deterioration of the environment through depletion of resources such as air, water and soil and habitat destruction

Immigration

coming into an area as part of a permanent move (in common language this combines the terms immigration and emigration)

Population distribution

the pattern of where people live

Industrial Revolution

economic and social changes resulting from technology changes that started in England in 1760 - moving away from hand tools to power-driven machines

Agricultural density

the ratio of the number of farmers to the amount of arable land

Arable land

land that can be farmed

Arithmetic density

the total number of people divided by the total land area

Ecumene

the permanently inhabited portion of the earth as distinguished from the uninhabited or temporarily inhabited area

Intervening opportunity

a favorable circumstance that causes people to stop a planned migration to take advantage of the prospect

Physiological density

the number of people per unit of area of arable land

Pull factor

a motivator that draws people into an area

Push factor

a force that motivates people to leave an area

Carrying capacity

the maximum population size of the species that the environment can sustain

Overpopulation

when there are not enough resources in an area to support a population

Replacement-fertility level

when a population is neither growing or shrinking but staying about the same (an NIR of 0 or TFR of 2.1)

Age/sex ratio

comparison of the numbers of males and females of different ages

Population pyramid

a graph of the population of an area by age and sex - when a population is growing it takes a pyramid shape, hence the name

It visually represents the distribution of various age groups in a population, showing the proportion of males and females. The shape can indicate the growth tendencies and demographics of the area.

Zero population growth (ZPG)

when a country reaches replacement level fertility

Crude Birth Rate (CBR)

the number of live births per one thousand people in the population

Crude Death Rate (CDR)

the number of deaths per one thousand people in the population

Demography

the study of population

Doubling time

the time period it takes for a population to double in size

Fecundity

fancy word for fertility

Fertility

the number of live births occuring in a population

Infant mortality rate (IMR)

the number of children who don't survive their first year of life per 1000 live births in a country

Medical revolution

leap forward in medical technology and practices that have enabled people to live longer

Mortality

the number of deaths occuring in a population

Rate of Natural Increase (RNI) (also known as NIR)

(birth rate - death rate)/10 - a positive NIR means a population is growing and a negative NIR means a population is shrinking

Total fertility rate (TFR)

the average number of children a woman is predicted to have in her child bearing (fecund) years