Syllabus: Population Geography the changing nature, rate and distribution of the world’s population spatial patterns of fertility and mortality types, volumes and directions of population movements such as rural-urban migration, labour migration and refugee migration issues arising from the changing size and distribution of population including environmental, economic and social impacts.

Trends in World Population

Global population growth At present, the world's population is growing fast - though this has not always been the case.  Until the 1800s the world's population grew steadily but slowly for thousands of years.  In 1820 the world's population reached one billion.

Global population growth  150 years later, in the early 1970s, the world's population reached three billion.  In 1999, less than 30 years later, the population doubled to six billion.  The global rate of population growth is now very fast (rising by about one billion every 15 years).

Global population growth The graph shows this pattern of accelerating growth:

Causes and rates of change The population of any place changes over time. There are three main causes of population change: Births - usually measured using the birth rate (number of live births per 1000 of the population) Deaths - usually measured using the death rate (number of deaths per 1000 of the population) 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, and you calculate the natural increase by subtracting the death rate per 1000 population from the birth rate per 1000 population: natural increase = birth rate - death rate.

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 both low death rates and low birth rates. MEDCs

Patterns of population growth LEDCs on the other hand have high population-growth rates. Both birth rates and death rates in LEDC populations tend to be high. As LEDCs develop, however, improving healthcare leads to death rates falling - while birth rates remain high. It is easy to see how this leads to even higher population- growth rates.LEDCs

The table shows comparative birth rates, death rates and population-growth rates in some LEDC and MEDC countries:

Population growth in LEDCs Most LEDCs are experiencing rapid population growth. Most LEDCs are in stage two or three of the demographic transition model. This means that they have falling death rates, due to improving health care and greater access to modern medicine, while birth rates remain high.demographic transition model

Population growth in LEDCs

Shanghai Shanghai is growing at an extraordinary rate. Officially the population has been growing at 29.4 people per hour. But it’s not through birth that the population is growing, it’s migration. China is experiencing massive urbanisation - the process of people moving to cities.

Population change in MEDCs Most MEDCs are experiencing slow rates of population growth. Some are actually experiencing population decline.MEDCs Most MEDCs are in stage four of the demographic transition model. Those countries with a declining population could be said to be entering stage five. This means that the birth rate in their country has fallen below the death rate. Most MEDCs have a very low rate of natural increase. demographic transition modelnatural increase

Population change in MEDCs Birth rates in MEDCs are falling as women choose to have smaller families later in life. Contraception is easily available and well understood. This helps women to plan their families and to have a career too

An ageing population:ageing population As people live longer the structure of a population changes. Many MEDCs are now experiencing a significant increase in the numbers of elderly people as a proportion of the population as whole. As birth rates fall and people have smaller families, the number of young dependants is falling and the number of elderly dependants is rising.

An ageing population:ageing population In the near future this will mean that there are fewer people of working age to support the elderly population. To try to balance out an ageing population, some countries adopt a pro-natalist policy - that is, they encourage people to have more children by offering them benefits, such as better access to childcare and better conditions for maternity leave.pro-natalist