AP Hug 2.1-2.4

Common Pull Factors

People tend to settle near oceans, rivers, freshwater, and fertile soil

• People need food and water

• Oceans allow trade and commerce

People also gravitate to areas with economic opportunities, political stability, historical prevalence, and desired cultural preferences.

Common Push Factors

Too dry

• Difficult to grow Crops

Too wet

• Oversaturated soil kills Crops

Too cold or hot

• Difficult to live in

• Don't provide adequate resources

Population Density

The amount of people in an area

Population Distribution

The spread of people in an area

Arithmetic Density

Total Population/ Total Amount of Land

Physiological Density

Total Population/ Total Amount of Arable land

Shows much land needs to be produced from one unit of arable land

• Higher: Produce more food and higher environmental stress

  • Risk desertification and depletion of nutrients

  • Possibly needing to import food to support population

Agricultural Density

Farmers/ Total Amount of Arable Land

Shows how advanced the technology is/ how efficient society is as producing food

• Higher: Lower technological development in Agriculture or inefficient practices

• Lower: Less labor is needed and more efficient practices

Carrying Capacity

The amount of people that can be supported by the environment without damaging it.

Population Pyramids

Breakdown of societies sex and age at a given time

• Y Axis: Age

• X Axis: Amount of people

Sex Ratio

Number of Males Births/ Number of Female Births * 100

• Above 100: More Men present

• Below: More women present

Pre Reproductive Years

0-14 years old

Reproductive Years

15-44 years

Post Reproductive Years

45+

Dependency Ratio

How many people society has to support

• (Number of Children 0-14 +Number of Adults 65+)/ Working Age Population * 100

Child Dependency Ratio

Number of people Age 0-14/Number of People 15-64 * 100

Elderly Dependency Ratio

Number of people 65+/ Number of People 15-64 *100

Crude Birth Rate (CBR)

The total number of live births in a year for every 1000 people alive in society

Crude Death Rate (CDR)

The total number of deaths in a year for every 1000 people alive in a society

Total Fertility Rate (TFR)

The average number of children  women will have

Infant Mortality Rate (IMR)

The total number of deaths under one year of age in a year for every 1,000 live births

Natural Increase Rate (NIR)/ Rate of Natural Increase (RNI)

The percentage by which a population grows in a year

• CBR-CDR= NIR

Doubling Time

The amount of time it takes for a population to double in size

Pro-Natalist Policies

Policies that are created to help increase a societies birth rate

Anti-Natalist Policies

Policies that are created to help decrease a societies birth rate