Population
Population is defined as the sum of all inhabitants that live in an area. This
number is constantly varying as factors such as births and immigrations
increase it, and factors such as deaths and emigrations decrease it.
Like all biological populations, a human population can only grow as large as
external factors allow it. Food supply, disease, and environmental factors limit
the size of human populations. Additionally, world population growth is also
influenced by artificial factors. A few examples of these are social customs
regarding reproduction and technological developments in medicine and
public health.
Population distribution
Population distribution is the way in which people are spread across a given area. Geographers
study population distribution patterns at different scales: local, regional, national, and global.
Population density
Population density is the average number of people per square kilometer.
It is a way of measuring population distribution and shows whether an area is sparsely or densely populated.
Population density describes the average number of people living
in a given area (this is usually a square kilometer, or km2). It is calculated by dividing the total population by the
area of land
Population density = total population ÷ total land area in km²
𝑻𝒐𝒕𝒂𝒍 𝑷𝒐𝒑𝒖𝒍𝒂𝒕𝒊𝒐𝒏
𝑷𝒐𝒑𝒖𝒍𝒂𝒕𝒊𝒐𝒏 𝑫𝒆𝒏𝒔𝒊𝒕𝒚 =
𝑻𝒐𝒕𝒂𝒍 𝒍𝒂𝒏𝒅 𝒂𝒓𝒆𝒂
There are other areas where few or no people live, such as in mountainous regions and deserts. These are
sparsely populated or have a low population density,
Population Density
The map shows patterns of population density on a global scale. Note that:
areas of high and low population density are unevenly spread across the world
the majority of places with high population densities are found in the northern hemisphere
The population density of a country has very little to do with its level of economic development. For example,
both Bangladesh and Japan are very densely populated, but Bangladesh is a LEDC and Japan is a MEDC
 If the number of people living in an area is greater than the resources and technology available to maintain an
adequate standard of living for the population, it is over-populated.
 If the number of people living in an area is less than is needed to make full use of the resources available, then the
area can be described as under-populated.
Singapore is the world’s most over-populated country, followed by Israel and Kuwait, according to a new league
table ranking countries by their degree of over-population.
The Over population Index, published by the Optimum Population Trust to mark World Population Day, is
thought to be the first international ‘league table’ to rank countries according to the sustainability of their
populations. It examines data for over 130 individual countries and concludes that 77 of them are over-populated –
they are consuming more resources than they are producing and are dependent on other
countries. These include China and India, along with many Middle Eastern and European countries .
Causes and rates of population change
The three main causes of population change
•Births rates- usually measured using the birth rate (number of live births per 1,000 of the population per year).
•Deaths rates- usually measured using the death rate (number of deaths per 1,000 of the population per year).
•Migration - the movement of people in and out of an area.
Rate of change
Births and deaths are natural causes of population change. The difference between the birth rate and the death rate of
a country or place is called the natural increase. The natural increase is calculated by subtracting the death rate from
the birth rate.
natural increase = birth rate - death rate
The rate of natural increase is given as a percentage, calculated by dividing the natural increase by 10.
For example, if the birth rate is 14 per 1,000 population, and the death rate is 8 per 1000 population, then the natural
increase = 14 - 8 = 6.
That is 6/1000, which is equal to 0.6%.
Patterns of population growth
Rates of population growth vary across the world. Although the world's total population is rising rapidly, not all countries are
experiencing this growth. In the UK, for example, population growth is slowing, while in Germany the population has started
to decline. MEDCs have low population growth rates, with low death rates and low birth rates.
• Population will decline if death rate is greater than birth rate.
• Population will increase if death rate is less than birth rate.
• LEDCs have high population growth rates. Both birth rates and death rates in LEDCs tend to be high. However, improving
healthcare leads to death rates falling - while birth rates remain high.
The table shows data in selected LEDC and MEDC countries. The figures are per 1,000 of the population per year.
Population growth in LEDCs
Most LEDCs are experiencing rapid population growth. Most LEDCs are in stage 2 or 3 of the demographic transition model.
This means that they have falling death rates, due to improving health care, while birth rates remain high. The recent history of
population management policies in China illustrates population change management problems.
Causes of population growth in LEDCs
 Limited access to family planning services and education about contraception. Contraception and other methods
of family planning may not be culturally or religiously acceptable.
 Children are a valuable source of labour and income for a family. They can work on the land from a young age
and as they get older they can earn money in other jobs.
 Children can help to care for younger children and elderly family members.
 High rates of infant mortality (infant deaths) mean that women need to have many children in order to ensure
that some survive through to adulthood.
 It may be traditional or culturally important to have a large family. LEDCs have a high population growth rate
which means that they have many young dependants.