Population

Demographers – scientists who study population

Population density – the average number of people living in a square mile or kilometer

Urban Migration – movement to cities

Population Definitions

Developed countries – countries that are industrialized

Developing countries – countries that are working toward industrialization

Birth and Death Rates

Birthrate – the number of people born each year per 1,000 people

Death rate - the number of deaths per year per 1,000 people

Annual Increase – the # by which the population is increasing each year

Doubling Time – the # of years it will take for a population to double at its current rate of growth

At current growth rates, the population of the earth will double in 50 years

Z.P.G. Zero Population Growth – population is holding steady

N.P.G. Negative Population Growth – population is decreasing

Population distribution – the way population is spread out over areas

Carrying capacity – the maximum number of people an environment can support

Population Definitions

Emigrate – to leave the country in which you were born

Immigrate – to arrive in a new country for permanent residence

Refugees – people who flee their country for refuge (safety) from persecution or disaster

Land

Habitable – supports life – you can live on it

Uninhabitable – does not support life Arable – will grow crops Non-Arable – will not grow crops Topsoil – the small layer of nutrient rich

soil that supports crop growth Soil erosion – washing away of valuable

topsoil