Reasons for & Implications of Different Population Structures (Cambridge (CIE) O Level Geography)

Population Pyramids

• The characteristics of a population, the distribution of age, sex, ethnicity, religion etc, is known as the population structure

• It is the result of changes in:

  • fertility

  • mortality

  • migration

• The two main components of age and sex can be shown on a population pyramid

Population pyramids

• Population pyramids (also known as an age structure graph) are used to display the gender and age structure of a given population

• They illustrate the distribution of the population across age groups and between male/female

• They enable governments nationally and regionally to assess the needs of the population for services such as healthcare and education

• This means the governments can estimate and plan for spending

• As countries develop and pass through the stages of demographic transition the shape of the population pyramid changes 

• The population pyramid can be used to identify the following groups:

  • Young dependents 

  • Old dependents 

  • Economically active (working population)

  • Dependency ratio 

Population Pyramid - Niger

• LEDCs like Niger have a concave pyramid shape

• At the start of stage 2 of the demographic transition model

• This indicates:

  • High birth rate

  • Low life expectancy

  • High death rate but starting to decrease

  • High infant mortality rate

  • Young dependent population dominates

Population Pyramid - Nepal

• LEDCs/NICs that are a little further along the demographic transition such as Nepal has a convex pyramid shape

• Stage 3 of the demographic transition model

• This indicates:

  • Decreasing birth rate 

  • Increasing life expectancy

  • Decreasing death rate

  • Decreasing infant mortality

  • Larger working age population

Population Pyramid - USA

• HIC countries such as the USA have a column shape

• Stage 4 of the demographic transition model

• This indicates:

  • Decreasing birth rate 

  • Increasing life expectancy

  • Decreasing death rate 

  • Low infant mortality

  • Larger working age population

Population Pyramid - Japan

• HIC countries such as Japan have a pentagon shape with a narrowing base

• Stage 5 of the demographic transition model

• This indicates:

  • Decreasing birth rate 

  • Increasing life expectancy

  • Death rate is higher than the birth rate due to the ageing population

  • Low infant mortality

  • Ageing population - older dependent population

Implications of population structure

• Population pyramids mean that population issues can be identified

• There are a range of issues including: 

  • Ageing populations

  • Falling birth rates 

  • Impacts of migration

Ageing populations

• Many HICs are experiencing ageing populations and an increase in the older dependent population, the implications of this include increased:

  • Pension payments

  • Need for care homes

  • Pressure on the healthcare service and social care

• It also results in fewer workers which means:

  • Governments are not able to collect as much tax

  • Some areas suffer worker shortages

Falling birth rates

• Countries experiencing falling birth rates include many HICs and MICs, the implications of this include:

  • School closures due to fewer children

  • Future workforce shortages 

Migration

• In some countries, migration can lead to an imbalance in the population structure

• The UAE has significantly more males than females 

• 29% of the population are males between the ages of 25 and 39 whereas only 10.5% of the population are women 25-39

• This is the result of the migration of males to the UAE to work in the oil, gas and construction industries

• Rapid population growth in some areas as a result of migration can lead to:

  • Increased pressure on services such as healthcare and schools

  • A shortage of housing

  • Increased traffic congestion

  • Increased water and air pollution

  • Shortage of food

  • Lack of clean water

Case Study: Japan

• Japan's population is decreasing, falling from 128 million in 2007 to 125.8 million in 2020

• The fertility rate is 1.36 births per woman which is well below the 2.1 fertility replacement rate

• The birth rate is 6.8 per 1000

• The death rate is 11.1 per 1000 

  • The death rate has increased from 6 per 1000 in 1979

  • This is not because healthcare or diets are worse but because there are far more elderly people who are more likely to become ill and die

• Japan has the highest life expectancy in the world at 84.36 years

• Increasing life expectancy in Japan has led to an ageing population with an increasing proportion of elderly dependents

• The issues that this has led to include:

  • Increased pressure on health and social care

  • Greater cost in providing pensions

  • More use of public transport as the elderly age group is less likely to drive

  • Increased need for care homes 

  • Shortages of workers as more people retire and there are not enough economically active people to take their place

• These issues are further increased by the falling birth rate 

• The future impact on Japan may include:

  • Increased taxes to cover health, social care and pension costs

  • Continued population decrease

  • Reduced economic development due to a shortage of workers

  • Reconsideration of the immigration policies which are currently very strict

  • Introduction of pro-natalist policies to increase the birth rate and encourage larger families