1.1 Population dynamics
Candidates should be able to:
• Describe and suggest reasons for the rapid increase in the world’s population in recent times, ‘the population explosion’.
• Define the main components influencing population growth – birth rate, death rate and migration.
• Describe the relationship between population growth and resources and explain why problems may result in some areas such as over-population and under-population.
• Identify and suggest reasons for contrasting patterns of population growth in different world areas as influenced by differences in birth rate, death rate and migration. Factors affecting these influences should be considered such as differences in social, economic and other factors, e.g. government policies and their impact upon birth rates, differences in health care, social and other factors influencing death rates, especially the impact of HIV/AIDS. These factors should be illustrated by reference to selected examples.
• Describe the consequences (benefits and problems) of different patterns of population growth. Consideration should be given to variations in the size and nature of dependent populations and standards of living.
• Identify and suggest reasons for different types of population structure as shown by age/sex pyramids. Candidates should be able to describe population pyramids and relate them to the different stages of the Demographic Transition Model.
• Identify the major influences on population density and population distribution. Reference should be made to physical, economic and human factors.
• Throughout their study of population, candidates should make use of statistics, graphs, diagrams and maps. Such exercises could bond the preparation of candidates for Paper 1 and the other components of the IGCSE Geography examination.
The study of population is often referred to as demography. Population is one of the most important IGCSE topics because other topics are based upon it and it always appears as a question in paper 1 of your examination.
Population Density: The number of people living in a given area, usually per km2. Singapore is a country with a very high population density and Australia is a country with a very low population density. El Salvador has the highest population density in Central America.
Population Distribution: This is how a population is spread out around a country or an area. If a country's population is distributed in a regular pattern then we say it has an even population distribution. However, if there are areas with many people and then areas with few people, then we would say that it has an uneven population distribution.
Looking at the map of Australia, you can see that it has a very uneven population distribution. If I was to describe the population distribution I might say:
There is a high concentration of people along the east and south east coast around Brisbane, Sydney and Melbourne
There is a small concentration on the south west coast around Perth
There is a concentration of people around the coast on the island of Tasmania
Most people live in coastal areas
Not many people live in the centre or north of Australia.
Two other good words to describe population are dense and sparse.
Sparse population: When not many people live in an area e.g. the centre of Australia.
Dense population: When a lot of people live in an area e.g. the Melbourne area.
If a question only asks you to describe distribution, then you just say what you see on the map, using words like dense, sparse, even and uneven. If places are named on the map, you can refer to place names, if not you can use compass points to help you describe.
If the question asks you to explain the population distribution, then you have to start giving reasons for the distribution. To do that you could some of the reasons found in the table below. Population distribution can be impacted by human and physical factors.
Causes of Sparse Population
Causes of Dense Population
Mountainous area e.g. Himalayas that are hard to build houses and transports links on.
Very hot or very cold area e.g. Sahara desert or Antarctica
A heavily forested area e.g. the Amazon Rainforest
Areas that flood a lot e.g. Mekong river delta
No jobs
Poor supply of electricity, gas and water
Poor communications
Shortage of natural resources
No schools or hospitals
Areas that regularly suffer from natural disasters e.g. volcanoes or droughts
Coastal areas that are good for fishing, trading etc.
A flat area of land that is easy to build on
Areas that are close to a good supply of water e.g. River Thames in London. Water is important for fishing, drinking, washing, etc.
Areas with good natural resources e.g. wood or good
Areas that are close to good fertile agricultural land
Areas with good developed transport links
Plenty of available jobs
Available electricity and water supply
Good communications e.g. internet and mobile phone network
Good quality schools and hospitals
World Population Growth
When describing a graph it is important look for trends, changes in trends e.g. quicker increase, slower increase and also anomalies (things that don't fit the general trend). It is also very important to support your findings with evidence (this means figures e.g. dates and population figures). Below is a good example describing the population graph to the right.
From 1750 to the present day the world's population has been constantly increasing. In 1750 the population was less than 1 billion. The population rose very slowly for the next two hundred years reaching 1.2 billion in 1850 and 2.7 billion in 1950. From 1950 to 2012 the population started to rise at a faster rate. By 1975 it reached about 4 billion and 2000 about 6 billion. In the last decade the population has increased at an even faster rate reaching 7 billion by 2012.
Population growth takes place when birth rates are higher than death rates (natural increase). In most continents of the world this is what is happening. The fastest rates of growth are actually happening in the poorest continents like Africa, Asia and South America. However, in Europe death rates are actually higher than birth rates so natural decrease is taking place.
Below is a table listing some of the reasons why birth rates are high in poorer countries (LEDCs), but death rates are decreasing and also why birth rates are low in richer countries (MEDCs).
Natural increase: When birth rates are higher than death rates.
Natural decrease: Where death rates are higher than birth rates.
Birth rates: The number of births per 1000 of population per year.
Fertility rate: The average number of children a female is expected to have in their lifetime.
Death rates: The number of deaths per 1000 of population per year.
BIRTH RATES
DEATH RATES
HIGH
Lack of contraception e.g. condoms
Religious beliefs e.g. belief against contraception and abortion (Roman Catholicism)
Agricultural based society (need for people to farm and collect water)
High infant mortality (if some babies may die, couples will be tempted to have more children)
No care homes or pensions so old dependents will need their children to care for them in old age.
Pro-natalist policies (governments encouraging couples to have more children)
Natural disasters (often only causes short term increases) e.g. Indian Ocean tsunami
Conflicts and wars
Poor medical care
Poor hygiene and sanitation
Poor diet (might be a shortage of food or unhealthy food)
Drinking alcohol, smoking or taking drugs
Lack of exercise (sedentary lifestyle)
Shortage of clean water
Diseases e.g. cancer and AIDS
LOW
Availability and affordability of contraception e.g. cheap or free condoms
Emancipation (freedom) of women (freedom to get an education and work)
Improved levels of education (especially female)
Reduced infant mortality
Introduction of pensions and care homes
Development of economy into secondary and tertiary sectors
Increasing cost of children
Delayed marriages and less children
Anti-natalist policies e.g. China's one child policy
High cost of raising children
Immunisation programs e.g. small pox
Availability of clean water
Improved diet and knowledge of diet e.g. five portions of fruit and diet
Improved levels of exercise
Improved medical care
Improved preventative testing e.g. for cancer so people can be treated before it kills them
Infant mortality: The number of deaths before the age of 1, per 1000 live births per year.
Life expectancy: The average age that someone is expected to live within a country. Generally women tend to live a few years longer than men.
Demographic Transition Model (DTM)
Demographic means population and transition means change, so the DTM basically means the population change model. The DTM looks at how a country's population may change as it develops. It looks at birth rates, death rates and total population. The DTM is usually divided into five stages. Stage 1 is the poorest stage and stage 5 is the richest stage.
Stage 1: Has birth and death rates. Because birth rates and death rates are both high (no contraception, agricultural based economy, poor medical care, etc.), total population remains low. Stage 2: Birth rates remain high, but death rates begin to fall. This causes total population to increase (natural increase). Death rates fall because of introduction of basic medical care. Stage 3: Birth rates begin to fall, but still remain higher than death rates so total population continues to increase. Birth rates begin to fall because of better education and availability of contraception. Stage 4: Birth rates and death rates are both low so the total population becomes constant (stays the same). Stage 5: Birth rates start to fall below death rates so the total population actually starts to decline (natural decrease). This is because of delayed marriages, cost of children and emancipation of women.
Natural population increase: When birth rates are higher than death rates, like in stage 2 and 3 of the DTM.
Natural population decrease: When death rates are higher than birth rates, like in stage 5 of the DTM.
A country's population can also be changed by immigration and emigration, but when there is reference to natural change, it only refers to changes caused by birth rates and death rates.
Population explosion or population bomb: The rapid growth in population, this might refer to the rapid growth of the world's population in the lat 100 years, or the rapid population growth of just one country.
Despite having very high rates of HIV and AIDS South Africa has experienced population growth over the last century. South Africa's population has grown because of a combination of natural increase and net migration gain. South African has experienced natural increase because birth rates have remained high while death rates have begun to fall.
Reasons for high birth rates include:
Lack of education about family planning
Poor availability of contraception and cost of contraception
Polygamy amongst some ethnic groups
Primary based economy
High rate of sexual violence often leading to unwanted pregnancies
Reasons for declining death rates include:
Better testing for and treatment of HIV/AIDS
Improved water supply
Improved housing (although large numbers still live in informal settlements)
Better education about diet
South Africa also receives large numbers of migrants from countries like Zimbabwe, Mozambique and Swaziland. This is either because of lack of economic opportunities in these countries and/or political problems.
South Africa Population
Population Pyramids
Population Pyramid: A population pyramid shows the age and sex structure of the country. It is a type of graph that is divided into males and females and then age groups.
Young Dependents: The number or the percentage of the population under the age of 16.
Old Dependents: The number or the percentage of the population over the age of 65.
Economically Active: People between the ages of 16 and 65. This is basically the working group.
Obviously some people stay at school past the age of 16, some people retire before 65 and some people work after 65. Also some people between 16 and 65 might unemployed. However, when we are look at entire populations we have to look at averages (the norm).
Dependency Ratio: The ratio between the amount of dependents (old and young) and the economically active.
Population pyramids can be related to stages in the DTM. If a pyramid has a wide base it indicates high birth rates. If the groups reduce in size quickly it indicates high deaths rates. If there are a lot of old dependents it indicates high life expectancy. If the base curves in, it indicates falling birth rates.
Young and Old Populations (Dependent Populations)
Ageing Population: This is when the proportion of old dependents is increasing. This happens because life expectancy increases, but also because birth rates start to fall. This happens in stage 5 of the DTM (it is currently happening in very developed countries like Japan). A country with an ageing population might have a higher death rate than you expect, because old people eventually die even if there life expectancy is high.
Problems of Ageing population
Solutions to Ageing Population
There may be a shortage of workers (not enough economically active)
If there is a shortage of workers there are less tax payers and the government receives less money
Old people tend to get more sick, so there will be an increase in pressure on hospitals
In many countries retired people can claim pensions off the government. If there are a lot of old people this can be very expensive.
The government has to provide places in care homes or provide services so people can care for themselves at home e.g. meals on wheels
Increase the retirement age. In the UK the retirement age has increased from 65 to 67
Increase the amount of tax charged to economically active.
Introduce private healthcare, so that the government doesn't have to pay
Encourage people to have private pensions so that the government does not have to pay
Economic immigration could be encouraged to reduce the dependency ratio
Have a pro-natalist policy so that birth rates and the number of young people increase
Retirement Age: The age at which people officially stop working. In many countries they can claim a pension off the government when they stop working. People have retired are often called pensioners because they receive a pension.
Pensions: Money that people who have retired receive. The money may be received from the government or from private pensions.
Despite there being many problems of an ageing population, there are some advantages, including:
Less need to spend money on schools
Older people are less likely to commit crimes
Old people tend to travel less (no commuting) so congestion and pollution might reduce.
Young Population: When talking about a young population, you are usually referring to young dependents (those under the age of 16). You might refer to a young population if there are too many or too few. Both can present advantages and disadvantages.
Problems of Young Population (too many)
Solutions of Young Population (too many)
Child care has to be provided so that parents can return to work.
Governments need to pay so that young people can go to school
Young people get sick so the government has to pay for healthcare
An increase in the dependency ratio
Creation of teaching and nursing jobs.
An anti-natalist policy might be introduced like China's one child policy.
Increase family planning. Make contraception available and affordable
Ensure females are educated and emancipated.
Problems of Young Population (too few)
Problems of Young Population (too few)
Closure of child related services and loss of jobs e.g. schools and nurseries
Less consumers and taxpayers in the future
An increase in the age of the population
Birth rates fall below replacement rate cause the population decline. Also in the future there will be less people in the reproductive age range causing further declines.
A pro-nalalist policy to increase birth rates.
Subsidised childcare and education to encourage more families to have more children.
Replacement Rate: The number of children each couple has to have to maintain a country's population. The replacement rate is about 2.1 - two to replace the couple when they die and then 0.1 for children who might die in infancy or who are unable to have children themselves (infertile).
Reproductive age range: The age that females normally have babies. Biologically this can be anytime between puberty and menopause but is more likely to be between 18 and 35.
Below are some advantages of a large and small young population:
Potentially large workforce in the future (too many)
Population who has grown up understanding modern technology e.g. computers and the internet (too many)
Reduced dependency ratio (too few)
Reduced education and medical costs (too few)
Dependents are cared for differently in LEDCs and MEDCs. In LEDCs the focus is very much on families to care for dependents, whereas in MEDCs there is a lot more assistance from the state (government) as well. Look at the document below to see some of the ways dependents are cared for.
Japan has an ageing population because the birth rates have fallen and it has one of the world's highest life expectancy's. In fact the islands of Okinawa off Japan's south coast have the highest life expectancy and the greatest percentage of centenarians.
Japan has the highest proportion of old dependents (about 23%) and the lowest proportion of young dependents (about 13%) in the world. It has a total fertility rate of only 1.25. This is well below the replacement rate of 2.1.
Even though the Japanese are working longer, it may have to look outside its borders to prevent future population decline and economic decline. Japan is traditionally a very insular (closed) country so allowing large scale immigration would involve huge social and cultural changes.
Centenarian: Someone over the age of 100.
Pro and Anti Natalist Birth Policies
Pro-natalist Policy: A policy that encourages couples to have more children. You can not force people to have more children so you have to offer incentives instead e.g. free childcare or even money.
Governments may have a pro-natalist policy if they have a declining population and a shortage of young dependents (low birth rates and fertility rates). A government can't force couples to have more children, so instead it must offer incentives. Incentives may include:
Cash payments
Free or subsidised healthcare
Free or subsidised education
Free nurseries or subsidised childcare.
Reduced tax rates
Child benefits e.g. weekly or monthly payments
Free equipment e.g. pushchairs, cots or even washing machines
Singapore is a developed country in SE Asia with a population of about 5 million people. For many years the Singaporean government has believed that Singapore is underpopulated and has tried to increase its population. Singapore has one of the lowest total fertility rates in the world, standing at 1.1, which is well below the replacement rate of 2.1. Already 36% of the Singapore population is made up of foreign nationals and in some sectors like industry, 80% of the workers are foreign.
To overcome worker shortages, the Singapore government has encouraged immigration, but it is also trying to increase the population through raising birth rates. The government is doing this in a number of ways. It has increased maternity leave by 50% to 12 weeks and it will cover the cost of maternity leave (the cost to the parents employers) for the first four babies. The Singapore government is also increasing child benefits paid to families. The government will pay money into a special bank account of up to nearly $1000 for six years. The Singapore government has also sponsored dating organisations to encourage people to get married earlier and start having children.
If Singapore's policies are not successful it will become increasingly dependent on foreign workers, gradually see an increase in the dependency ratio and ultimately economic decline.
Anti-natalist policy: A policy that attempts to reduce birth rates. This might be through better education and supply of contraception or through much stricter policies like China's one child policy.
China - One Child Policy
After China were invaded and occupied by Japan in the World War II, they wanted to strengthen their military so that it never happened again. To do this they encouraged citizens to have more children, because a bigger population potentially meant a stronger army. This policy would have been fine if China had the resources and technology to match. However, they did not and coupled with the crippling policies of the cultural revolution, mass famines ensued. It is estimated that up to 30 million died during the 1960's and 1970's. This was not a sustainable policy, so the Chinese government was forced to introduce an anti-natalist policy.
The policy China decided to introduce was extremely strict and probably not possible in a non-communist country. The government stated that from 1979 all couples were only allowed to have one child. They also increased the marriageable age of men to 22. To get married and to have a child, citizens had to apply to the government. If you applied by these rules you were entitled to free education, healthcare, housing and given a job. If you did not follow the rules, then benefits would be removed and females who were found to be pregnant were given forced abortions and even sterilised.
To enforce the policy the government relied on community enforcement. Often elderly residents who were trusted within the community were asked to inform, elderly female informants were nicknamed 'granny police'. The strict enforcement of the policy led to a problem of female infanticide. This is the killing of female babies, because couples favoured male children. Males ensured the family name was maintained and were able to work manual jobs, whereas females would be lost after marriage (females normally went to live with their husbands family).
There were a number of exceptions to the rules, if you had twins or triplets this was fine, if your first child had a physical or mental disability you could have a second, families in rural areas (farming areas) were often allowed a second, ethnic minorities were allowed a second and often couples who bribed officials could have a second.
The policy has been relatively successful, birth rates have fallen from a peak off 44 in the 1950's down to just 12. China's population is also expected to peak in the next 20 years and then slowly start to decrease. Because of its success there have been further relaxations including:
All of families in females areas can now have two
Two people who marry from single children families they are allowed two
Females are better educated about contraception and are free to make their own choices.
However, there are also a few problems:
China is still overpopulated, there are over 1.3 billion Chinese
There is a male female imbalance in the population
Overpopulation, Underpopulation and Optimum Population
Carrying Capacity: The amount of people that the resources of a country can support. The carrying capacity of a country can change with improvements in technology e.g. desalination, discoveries of new resources, or the loss of existing resources e.g. volcanic eruption destroying farm land.
Overpopulation: When there are more people that the resources available. Overpopulation might lead to unemployment, famine and homelessness.
Underpopulation: When there are not enough people to fully maximise the potential of a country. For example there might be vacant jobs or resources that can not be fully exploited.
Optimum Population: When population and resources are perfectly matched. In reality this is almost impossible to achieve.
PROBLEMS OF OVERPOPULATION
PROBLEMS OF UNDERPOPULATION
There could be unemployment because there are not enough jobs for everyone
There could be a shortage of schools and hospitals
There could be a shortage of hoses and informal settlements grow
Congestion may increase as there are more cars, buses, etc. on the road
Prices may increase as demand for houses, resources, etc. increase (inflation)
There may be a shortage of clean drinking water, electricity, etc.
There may be an increase in air, noise and water pollution e.g. open sewers, fires, etc.
The rural-urban fringe may be damaged as informal settlements are built
There are a shortage of workers
There will be less people paying tax
Schools and hospitals may close because there are not enough clients
Public transport links might close because of less customers
There may be less innovation and development (lee brain power)
Not possible to exploit all resources
Hard to defend country
Necessary to attract migrants
China - Intra country carrying capacities
A country's carrying capacity might vary within its borders - China is an excellent example of this. The west and north of China will have a fairly low carrying capacity. This is because the west is fairly mountainous and the north is mainly desert. However, the east will have a much higher carrying capacity because it is flatter, has good water supply (Yellow and Yangtse rivers) and is near the coast.
Theories about population and resources:
Malthus: Malthus looked at population and resources and believed that population was growing at a much fast rate than resources. He believed that this would cause a series of preventative and positive checks. Preventative checks would be people trying to reduce population growth themselves and positive checks would be famines and conflicts.
Boserup: Boserup was a more optimistic person who believed that humans always came up with solutions to problems. Her famous saying was 'necessity is the mother of invention' which basically means that humans will also find a solution to resource shortages e.g. desalination, development of renewable energy.
Disease (HIV and AIDS)
HIV: Human immunodeficiency virus
AIDS: Acquired immune deficiency syndrome
HIV was first discovered in 1981 and is believed to be a virus that crossed over from monkeys to humans in Africa (in Africa it is very common for people to eat bush meat like monkeys). Worldwide, AIDS has killed over 25 million people and nearly 3 million extra people became infected in 2009. HIV is the virus that you catch and AIDS is basically the name for all the symptoms you catch when your immune system has been degraded. People normally die from diseases that they have caught because of there weak immune system e.g. pneumonia. When HIV was first discovered, victims would have a fairly short like expectancy (a few years). However, even though there is still no cure peoples lives can be prolonged for years because of drugs designed to support your immune system.
HIV is transmitted through infected bodily floods (blood, seamen and breast milk - it is not possible to transmit through saliva). The infected bodily flood needs to come into contact with another persons bodily fluids or mucous membranes found in the mouth, nose, ears and genital areas. Therefore some of the most common ways of transmitting HIV are:
Unprotected sexual intercourse with a HIV sufferer
Sharing needles with an infect HIV sufferer (common amongst drug users)
Receiving a blood transfer from infected blood (nearly all blood around the world is now tested)
Breast feeding
Mother to unborn child (this can be prevented if the mother knows that she is infected).
Africa is the continent that has been hardest hit by HIV. As you can see from the map over 15% of the adult population in Southern Africa suffer from HIV, this is as high as 40% in some countries like Botswana. However, even with these high figures, the true figures might be a lot higher because not everyone has been tested.
CAUSES OF HIGH HIV RATES
IMPACTS OF HIV
SOLUTIONS TO HIV
Lack of education about HIV (causes, transmission, prevention).
Availability and affordability of condoms, as well as knowledge of how they are used.
Pologymy. The tradition of taking more than one wife.
Lack of testing. Much of the population does not know that it has HIV.
Prostitution. Many prostitutes are infected but don't know so continue to transmit the disease.
Sexual crime. There is a high rate of sexual crime in South Africa which helps spread the disease
Urban myths. Many uneducated people believe myths about HIV that are untrue. For example Jacob Zuma believed a shower after sex would reduce chance of catching HIV.
Migrant population. When a lot of people move for work HIV can be spread easily between communities.
Religious beliefs. some religions don't allow the use of condoms. However, it must also be remembered most religions discourage sex before marriage and promote only one sexual partner (husband and wife)
Poor medical hygiene - possibly dirty medical equipment and untreated blood
Individually, people will experience a decline in their immune system, becoming sicker and possibly dieing.
High cost of having to treat HIV and AIDS patients.
There will be an effective increase in the dependency ration because less people will be able to work because of sickness.
The country may see a reduction in tourism and investment as people are reluctant to travel to a country with high infection rates.
The country will have to pay large amounts of money to be able to buy anti-retroviral drugs (this is not a cure, but it helps support victims immune system).
Life expectancy rapidly reduces in countries with high infection rates and death rates increase.
There are a large number of orphans as many parents die.
There may be a shortage of workers which can lead to economic decline and food shortages. There may not be enough essential workers like teachers.
Providing free condoms and educating people about how to use them correctly.
Educating about what HIV is and explaining how the spread can be reduced and stopped. Because many people in rural Africa may be illiterate education might have to be done through posters or theatre (drama).
Test more people to find out who is infected.
Legalise prostitution to encourage more prostitutes to be tested and hopefully reduce the spread of HIV
Anti-retroviral drugs can be sold cheaper so that more people have access to them
Hopefully, scientists will eventually find a cure for HIV so that it can be eliminated.
Encouraging no sex before marriage and trying to reduce the number of peoples sexual partners.
Try and reduce the stigma of HIV and AIDS so more people talk about it and are happy to be tested.
Lesotho is a landlocked country situated inside South Africa. It has a population of only 1.8 million. It is estimated that over 20% of Lesotho adults population is infected with HIV or AIDS. In reality the figure might be much higher because many adults have not been tested.
In Lesotho one innovative to reduce infection rates is to test every adult. 7,500 health care workers have been employed to test every person. They are even going door to door with testing kits.
Lesotho is now also going to benefit from an agreement made by drugs companies to lower their prices. In the future anti-retroviral drugs are going to be 50% cheaper and HIV tests 30% cheaper.
IGCSE Population and GCSE Population
Specification:
1.1 Population dynamics
Candidates should be able to:
• Describe and suggest reasons for the rapid increase in the world’s population in recent times, ‘the population explosion’.
• Define the main components influencing population growth – birth rate, death rate and migration.
• Describe the relationship between population growth and resources and explain why problems may result in some areas such as over-population and under-population.
• Identify and suggest reasons for contrasting patterns of population growth in different world areas as influenced by differences in birth rate, death rate and migration. Factors affecting these influences should be considered such as differences in social, economic and other factors, e.g. government policies and their impact upon birth rates, differences in health care, social and other factors influencing death rates, especially the impact of HIV/AIDS. These factors should be illustrated by reference to selected examples.
• Describe the consequences (benefits and problems) of different patterns of population growth. Consideration should be given to variations in the size and nature of dependent populations and standards of living.
• Identify and suggest reasons for different types of population structure as shown by age/sex pyramids. Candidates should be able to describe population pyramids and relate them to the different stages of the Demographic Transition Model.
• Identify the major influences on population density and population distribution. Reference should be made to physical, economic and human factors.
• Throughout their study of population, candidates should make use of statistics, graphs, diagrams and maps. Such exercises could bond the preparation of candidates for Paper 1 and the other components of the IGCSE Geography examination.
The study of population is often referred to as demography. Population is one of the most important IGCSE topics because other topics are based upon it and it always appears as a question in paper 1 of your examination.
Population Density: The number of people living in a given area, usually per km2. Singapore is a country with a very high population density and Australia is a country with a very low population density. El Salvador has the highest population density in Central America.
Population Distribution: This is how a population is spread out around a country or an area. If a country's population is distributed in a regular pattern then we say it has an even population distribution. However, if there are areas with many people and then areas with few people, then we would say that it has an uneven population distribution.
Two other good words to describe population are dense and sparse.
Sparse population: When not many people live in an area e.g. the centre of Australia.
Dense population: When a lot of people live in an area e.g. the Melbourne area.
If a question only asks you to describe distribution, then you just say what you see on the map, using words like dense, sparse, even and uneven. If places are named on the map, you can refer to place names, if not you can use compass points to help you describe.
If the question asks you to explain the population distribution, then you have to start giving reasons for the distribution. To do that you could some of the reasons found in the table below. Population distribution can be impacted by human and physical factors.
Causes of Sparse Population
Causes of Dense Population
World Population Growth
From 1750 to the present day the world's population has been constantly increasing. In 1750 the population was less than 1 billion. The population rose very slowly for the next two hundred years reaching 1.2 billion in 1850 and 2.7 billion in 1950. From 1950 to 2012 the population started to rise at a faster rate. By 1975 it reached about 4 billion and 2000 about 6 billion. In the last decade the population has increased at an even faster rate reaching 7 billion by 2012.
Population growth takes place when birth rates are higher than death rates (natural increase). In most continents of the world this is what is happening. The fastest rates of growth are actually happening in the poorest continents like Africa, Asia and South America. However, in Europe death rates are actually higher than birth rates so natural decrease is taking place.
Below is a table listing some of the reasons why birth rates are high in poorer countries (LEDCs), but death rates are decreasing and also why birth rates are low in richer countries (MEDCs).
Natural increase: When birth rates are higher than death rates.
Natural decrease: Where death rates are higher than birth rates.
Fertility rate: The average number of children a female is expected to have in their lifetime.
Death rates: The number of deaths per 1000 of population per year.
BIRTH RATES
DEATH RATES
HIGH
LOW
Life expectancy: The average age that someone is expected to live within a country. Generally women tend to live a few years longer than men.
Demographic means population and transition means change, so the DTM basically means the population change model. The DTM looks at how a country's population may change as it develops. It looks at birth rates, death rates and total population. The DTM is usually divided into five stages. Stage 1 is the poorest stage and stage 5 is the richest stage.
Stage 1: Has birth and death rates. Because birth rates and death rates are both high (no contraception, agricultural based economy, poor medical care, etc.), total population remains low.
Stage 2: Birth rates remain high, but death rates begin to fall. This causes total population to increase (natural increase). Death rates fall because of introduction of basic medical care.
Stage 3: Birth rates begin to fall, but still remain higher than death rates so total population continues to increase. Birth rates begin to fall because of better education and availability of contraception.
Stage 4: Birth rates and death rates are both low so the total population becomes constant (stays the same).
Stage 5: Birth rates start to fall below death rates so the total population actually starts to decline (natural decrease). This is because of delayed marriages, cost of children and emancipation of women.
Natural population decrease: When death rates are higher than birth rates, like in stage 5 of the DTM.
A country's population can also be changed by immigration and emigration, but when there is reference to natural change, it only refers to changes caused by birth rates and death rates.
Population explosion or population bomb: The rapid growth in population, this might refer to the rapid growth of the world's population in the lat 100 years, or the rapid population growth of just one country.
Population Growth
Despite having very high rates of HIV and AIDS South Africa has experienced population growth over the last century. South Africa's population has grown because of a combination of natural increase and net migration gain. South African has experienced natural increase because birth rates have remained high while death rates have begun to fall.
Reasons for high birth rates include:
Reasons for declining death rates include:
South Africa also receives large numbers of migrants from countries like Zimbabwe, Mozambique and Swaziland. This is either because of lack of economic opportunities in these countries and/or political problems.
Population Pyramids
Young Dependents: The number or the percentage of the population under the age of 16.
Old Dependents: The number or the percentage of the population over the age of 65.
Economically Active: People between the ages of 16 and 65. This is basically the working group.
Obviously some people stay at school past the age of 16, some people retire before 65 and some people work after 65. Also some people between 16 and 65 might unemployed. However, when we are look at entire populations we have to look at averages (the norm).
Dependency Ratio: The ratio between the amount of dependents (old and young) and the economically active.
Population pyramids can be related to stages in the DTM. If a pyramid has a wide base it indicates high birth rates. If the groups reduce in size quickly it indicates high deaths rates. If there are a lot of old dependents it indicates high life expectancy. If the base curves in, it indicates falling birth rates.
Young and Old Populations (Dependent Populations)
Ageing Population: This is when the proportion of old dependents is increasing. This happens because life expectancy increases, but also because birth rates start to fall. This happens in stage 5 of the DTM (it is currently happening in very developed countries like Japan). A country with an ageing population might have a higher death rate than you expect, because old people eventually die even if there life expectancy is high.
Problems of Ageing population
Solutions to Ageing Population
Japan's Population To shrink by one third by 2060 - BBC article
Retirement Age: The age at which people officially stop working. In many countries they can claim a pension off the government when they stop working. People have retired are often called pensioners because they receive a pension.
Pensions: Money that people who have retired receive. The money may be received from the government or from private pensions.
Despite there being many problems of an ageing population, there are some advantages, including:
Young Population: When talking about a young population, you are usually referring to young dependents (those under the age of 16). You might refer to a young population if there are too many or too few. Both can present advantages and disadvantages.
Problems of Young Population (too many)
Solutions of Young Population (too many)
Problems of Young Population (too few)
Problems of Young Population (too few)
Reproductive age range: The age that females normally have babies. Biologically this can be anytime between puberty and menopause but is more likely to be between 18 and 35.
Below are some advantages of a large and small young population:
Dependents are cared for differently in LEDCs and MEDCs. In LEDCs the focus is very much on families to care for dependents, whereas in MEDCs there is a lot more assistance from the state (government) as well. Look at the document below to see some of the ways dependents are cared for.
Japan's Ageing Population
Japan has an ageing population because the birth rates have fallen and it has one of the world's highest life expectancy's. In fact the islands of Okinawa off Japan's south coast have the highest life expectancy and the greatest percentage of centenarians.
Japan has the highest proportion of old dependents (about 23%) and the lowest proportion of young dependents (about 13%) in the world. It has a total fertility rate of only 1.25. This is well below the replacement rate of 2.1.
Even though the Japanese are working longer, it may have to look outside its borders to prevent future population decline and economic decline. Japan is traditionally a very insular (closed) country so allowing large scale immigration would involve huge social and cultural changes.
Centenarian: Someone over the age of 100.
Pro and Anti Natalist Birth Policies
Pro-natalist Policy: A policy that encourages couples to have more children. You can not force people to have more children so you have to offer incentives instead e.g. free childcare or even money.
Governments may have a pro-natalist policy if they have a declining population and a shortage of young dependents (low birth rates and fertility rates). A government can't force couples to have more children, so instead it must offer incentives. Incentives may include:
Vladamir Putin reveals plan to boost Russia birth rate - BBC article
Australia's birth rate at 25 year high - Reuters article
Singapore's birth rate challenges - Asiaone news
Lie back and think of the bank balance - Taipei Times
France plans to pay cash for more babies - Guardian article
Singapore's Pro-natalist Policy
Singapore is a developed country in SE Asia with a population of about 5 million people. For many years the Singaporean government has believed that Singapore is underpopulated and has tried to increase its population. Singapore has one of the lowest total fertility rates in the world, standing at 1.1, which is well below the replacement rate of 2.1. Already 36% of the Singapore population is made up of foreign nationals and in some sectors like industry, 80% of the workers are foreign.
To overcome worker shortages, the Singapore government has encouraged immigration, but it is also trying to increase the population through raising birth rates. The government is doing this in a number of ways. It has increased maternity leave by 50% to 12 weeks and it will cover the cost of maternity leave (the cost to the parents employers) for the first four babies. The Singapore government is also increasing child benefits paid to families. The government will pay money into a special bank account of up to nearly $1000 for six years. The Singapore government has also sponsored dating organisations to encourage people to get married earlier and start having children.
If Singapore's policies are not successful it will become increasingly dependent on foreign workers, gradually see an increase in the dependency ratio and ultimately economic decline.
Anti-natalist policy: A policy that attempts to reduce birth rates. This might be through better education and supply of contraception or through much stricter policies like China's one child policy.
China - One Child Policy
After China were invaded and occupied by Japan in the World War II, they wanted to strengthen their military so that it never happened again. To do this they encouraged citizens to have more children, because a bigger population potentially meant a stronger army. This policy would have been fine if China had the resources and technology to match. However, they did not and coupled with the crippling policies of the cultural revolution, mass famines ensued. It is estimated that up to 30 million died during the 1960's and 1970's. This was not a sustainable policy, so the Chinese government was forced to introduce an anti-natalist policy.
The policy China decided to introduce was extremely strict and probably not possible in a non-communist country. The government stated that from 1979 all couples were only allowed to have one child. They also increased the marriageable age of men to 22. To get married and to have a child, citizens had to apply to the government. If you applied by these rules you were entitled to free education, healthcare, housing and given a job. If you did not follow the rules, then benefits would be removed and females who were found to be pregnant were given forced abortions and even sterilised.
To enforce the policy the government relied on community enforcement. Often elderly residents who were trusted within the community were asked to inform, elderly female informants were nicknamed 'granny police'. The strict enforcement of the policy led to a problem of female infanticide. This is the killing of female babies, because couples favoured male children. Males ensured the family name was maintained and were able to work manual jobs, whereas females would be lost after marriage (females normally went to live with their husbands family).
There were a number of exceptions to the rules, if you had twins or triplets this was fine, if your first child had a physical or mental disability you could have a second, families in rural areas (farming areas) were often allowed a second, ethnic minorities were allowed a second and often couples who bribed officials could have a second.
The policy has been relatively successful, birth rates have fallen from a peak off 44 in the 1950's down to just 12. China's population is also expected to peak in the next 20 years and then slowly start to decrease. Because of its success there have been further relaxations including:
However, there are also a few problems:
China facing growing gender imbalance - BBC article
Has China's one child policy worked - BBC article
Overpopulation, Underpopulation and Optimum Population
Carrying Capacity: The amount of people that the resources of a country can support. The carrying capacity of a country can change with improvements in technology e.g. desalination, discoveries of new resources, or the loss of existing resources e.g. volcanic eruption destroying farm land.
Overpopulation: When there are more people that the resources available. Overpopulation might lead to unemployment, famine and homelessness.
Underpopulation: When there are not enough people to fully maximise the potential of a country. For example there might be vacant jobs or resources that can not be fully exploited.
Optimum Population: When population and resources are perfectly matched. In reality this is almost impossible to achieve.
PROBLEMS OF OVERPOPULATION
PROBLEMS OF UNDERPOPULATION
A country's carrying capacity might vary within its borders - China is an excellent example of this. The west and north of China will have a fairly low carrying capacity. This is because the west is fairly mountainous and the north is mainly desert. However, the east will have a much higher carrying capacity because it is flatter, has good water supply (Yellow and Yangtse rivers) and is near the coast.
Theories about population and resources:
Malthus: Malthus looked at population and resources and believed that population was growing at a much fast rate than resources. He believed that this would cause a series of preventative and positive checks. Preventative checks would be people trying to reduce population growth themselves and positive checks would be famines and conflicts.
Boserup: Boserup was a more optimistic person who believed that humans always came up with solutions to problems. Her famous saying was 'necessity is the mother of invention' which basically means that humans will also find a solution to resource shortages e.g. desalination, development of renewable energy.
Disease (HIV and AIDS)
HIV: Human immunodeficiency virus
AIDS: Acquired immune deficiency syndrome
HIV is transmitted through infected bodily floods (blood, seamen and breast milk - it is not possible to transmit through saliva). The infected bodily flood needs to come into contact with another persons bodily fluids or mucous membranes found in the mouth, nose, ears and genital areas. Therefore some of the most common ways of transmitting HIV are:
Africa is the continent that has been hardest hit by HIV. As you can see from the map over 15% of the adult population in Southern Africa suffer from HIV, this is as high as 40% in some countries like Botswana. However, even with these high figures, the true figures might be a lot higher because not everyone has been tested.
CAUSES OF HIGH HIV RATES
IMPACTS OF HIV
SOLUTIONS TO HIV
Botswana mulls leaglising prostitution to fight HIV - BBC article
New anti-retroviral drugs help reduce HIV transmission - BBC article
Lesotho
Lesotho is a landlocked country situated inside South Africa. It has a population of only 1.8 million. It is estimated that over 20% of Lesotho adults population is infected with HIV or AIDS. In reality the figure might be much higher because many adults have not been tested.
In Lesotho one innovative to reduce infection rates is to test every adult. 7,500 health care workers have been employed to test every person. They are even going door to door with testing kits.
Lesotho is now also going to benefit from an agreement made by drugs companies to lower their prices. In the future anti-retroviral drugs are going to be 50% cheaper and HIV tests 30% cheaper.