Population

Population

1. Population distribution

   • The way in which people are spread across a given area
     • Different scales
       • Local
       • Regional
       • National
       • Global
     • Tends to be uneven
     • Population density
       • Average number of people per square kilometre
       • Way of measuring population distribution
         • Shows weather an area is densely or sparsely populated
       • The population density of a country has little to do with its level of economic development
         • Bangladesh = LEDC = densely populated
         • Japan = MEDC = densely populated
         • The majority of places with high population densitites are in the Northern hemisphere
           • Areas of densely or sparsely population are spread unevenly across the world
       • Factors affecting population density
         • Attract
           • Temperate climate
           • Low lying land
             • Fertile land
           • Good supplies of natural resources
         • Discourage
           • Extreme climates
             • Desert
           • Mountainous areas
             • Highland areas
           • Dense vegetation
             • Rainforest
         • Socioeconomic factors
           • Jobs
             • High wages
         • Political factors
           • Civil war

2. Global population growth

   • Steady growth until the 1800's
     • In 1820 the world's population reached 1 billion
       • In the early 1970's the world's population reached 3 billion
         • In 1999 the world's population doubled to 6 billion
           • Global rate of population growth is now 1 billion every 15 years
   • Population Pyramids
     • Show structure of population
       • Compares relative numbers of people in different age groups
         • Structures differ in LEDCs and MEDCs
   • Demographic transition models
     • Shows population change over time
   • Causes of population change
     • Natural causes
       • Death
         • Population will decline if death rate is higher than birth rate
       • Birth
         • The difference between the birth and death rates is called the natural increase
           • Subtract death rate from birth rate
         • Population will increase if birth rates are higher than death rates
           • LEDCs have high growth rates
             • Both birth rates and death rates tend to be high
     • Migration