The world population is now 7.97 billion and will most likely grow to 8 billion by the end of 2022. Just by using numbers, it is hard to imagine the sheer scale of what that means. It is easier to understand the impact of a rapidly-growing population not only by numbers but by looking at how the world is changing the economy, society, and environment. Let's look at the causes and consequences of this rapidly growing population and investigate what we need to be careful of with the effects of the rapid population growth.
Rapid population growth overview
A population overview: In the last few centuries, the global population growth has been growing quickly. Rapid population growth began in the 1800s when people worked out how to produce more food and control diseases. The UN estimated the world population reached one billion for the first time in 1804. The second billion was reached in 1927, 123 years after the first billion, but in 1960, only 33 years later, the population had reached three billion. Barely 40 years later, in 1999, the population had doubled to six billion. The global rate is growing at one billion every 15 years at present.
Fig. 1 - A historical graph of global population growth
Rapid population growth causes
The three leading causes of population growth are births, deaths, and migration. Births and deaths are seen as natural causes of population change. The difference between a country's birth and death rates is known as the natural increase, and by subtracting the death rate from the birth rate, you can calculate the natural increase. When the death rate is higher than the birth rate, there is a natural decrease in population. When the birth rate is higher than the death rate, there is a natural increase in population. The rate of natural increase is given as a percentage, calculated by dividing the natural increase by 10. However, migration can change the balance between the birth rate and death rate as people can immigrate and enter the country and emigrate and leave the country.
Birth rate - Birth rates are measured through the live births of babies born yearly per 1000 people in a population.
Death rate - Death rates are measured through the deaths yearly per 1000 people in a population.
Migration - Migration is the entering and leaving of a country.
The rate of change between births and deaths can result in rapid population growth. From 1750 to 1900, the death rate dropped rapidly as agricultural developments created more food supplies meaning less malnutrition and starvation; medical breakthroughs such as vaccines and improvements in healthcare led to fewer deaths; and public infrastructures such as sewers and water supplies helped with hygiene and reduced casualties.
Fig. 2 - world map showing countries by fertility rate of 2021
Did you know: ever since the end of the Black Death (bubonic plague) around 1350, the world population has been growing?
Rapid population growth in LEDCs
Currently, most less-economically developed countries (LEDCs) in stage 2 or 3 of the demographic transitional model are experiencing rapid population growth. They have falling death rates because of health care improvement and high birth rates.
There are multiple reasons for LEDCs having high birth rates. Children are considered sources of labour or carers for the elderly or young of the family. High infant mortality rates mean that mothers have many children to ensure that some survive to adulthood. It can be traditionally and culturally significant to have a large family, and there could be some difficulty in accessing family planning services with education about contraception.
Read our explanation of the Demographic transitional model to learn about birth rate, death rate, and economic growth patterns.
How to control rapid population growth
Controlling the population, in general, can be controversial as it touches upon controlling the three leading causes of rapid population growth: birth rates, death rates, and migration. There have been restrictive policies that restrain couples from having more than one child, such as the one-child policy in China. However, instead of controlling rapid population growth through the oppression of rights, there may be ways of providing people with an opportunity to learn how individually they can control their reproductive rights, which could lead to less rapid population growth.
Case study - One-child policy in China
The government introduced the one-child policy in China in the late 1970s. It meant that couples in China were only allowed to have one child. It was a way to reduce the birth rate and slow population growth. Previously, the government had encouraged people to have many children; however, in the 1970s, they realised this growth rate would be unsustainable. The positive effect of this policy would be that there would be education for all and benefits for childcare and healthcare.
However, there were problems when the policy was put in place. People who had more than one child would be fined and receive no benefits. The rural areas resisted as it was traditional to have large families. In urban areas, the policy was strictly enforced; however, it was hard to track in rural areas. There have been claims of pregnant women who already had one child being forced to have abortions and sterilised.
Fig. 3 - Ceramic mural of the one-child policy in China
The impact of the one-child policy was that birth rates fell to 0.7%. This rate is much lower than when it increased by 1.9% in the 1950s. It also impacted the gender balance in China. There are more men than women, as traditionally, boys were preferred over girls. Many baby girls were put in orphanages, and many abortions were female fetuses. In 2020, the sex ratio of China's total population was 105.302 males per 100 females. This means there are approximately 35 million more men than women, putting China in the 183rd position out of 201 countries/territories regarding the female-to-male ratio.
Reproductive rights
So if restrictive policies didn't work well, what could help slow down the rapid population growth? Creating opportunities for people to think about reproductive rights can lead to lowering birth rates. This can begin with promoting family planning and education about contraception. In Iran, a national family planning program changed the fertility rate of 5.6 births per woman to 2.6 in a decade. Empowering women with control over reproductive health can also help slow birth rates. Studies have shown that access to reproductive health services makes it easier to break out of poverty, and working women are likely to use birth control.
Impact of rapid population growth on socio economic development
There are positive and negative impacts of rapid population growth on socioeconomic development. The impacts can be seen prominently in LEDCs where rapid population growth occurs.
Socio-economic development is the development of social and economic aspects in society. It is usually measured with indicators such as gross domestic product (GDP), life expectancy, literacy, and employment levels.
There is increased employment which leads to higher wages and standards of living. This contributes to the country's economic growth, and the government can invest money into developing the country by improving services, education, and infrastructure. However, there are not always enough jobs to meet the growing demand, so people work longer hours in worse conditions with lower pay. There can be a lack of housing, schools, and infrastructure such as water and electricity, as areas struggle to keep up with the growing population. This can cause poor living conditions and poor health conditions.
Consequences of rapid population growth on environment
As the population continues to grow rapidly, there are mounting pressures on resources as there is an increase in demands, needs, and services. The destruction of the environment and pollution are the biggest consequences of rapid population growth.
Pollution and waste
The amount of waste grows with the growing population takes up space and pollutes the environment. Industrial growth and greenhouse gas release contribute to global warming. They can also produce smoke and dust particles and give off toxic chemical fumes, reducing air quality. Water quality can become degraded from the waste people and factories produce that is dumped in the water sources. In addition, it can become polluted from the runoff of chemical fertiliser and insecticides from agriculture.
Over-extraction
The extraction of resources from the environment, such as fossil fuels, timber, and water, is increasing. Overfishing can break down the ecosystems in the rivers and seas, and intensive farming can leave the land without nutrients. Water supplies in certain areas are being used so much that they have begun to dry out. This not only affects the people but can also affect the ecosystem that relies on water, such as the marine life living in the water and the animals that live around the water supply. Mining fossil fuels damage the land, and it can generate water and air pollution, which can affect the local communities. Timber extraction leads to deforestation, resulting in desertification, soil erosion, and flooding. Deforestation means less carbon dioxide is being absorbed and an increase in greenhouse gases in the atmosphere.
From 1950 to 1980, many forests in Nepal were cut down for timber and converted to land for farming. Deforestation was causing soil erosion, landslides, and downstream flooding. However, due to civil war and a bad economy with the government supporting workers going abroad, the migration for work abroad has led to forest recovery. Migration meant fewer people were dependent on agriculture and living off the land.
Overpopulated spaces
The spreading of urban spaces can destroy the natural environments of forests and habitats for wildlife. When urban areas take up natural environments, people can live side by side with wildlife, which carries diseases that can spread easily between people and animals.
Fig. 4 - Nilkhet Mor in Dhakar in Bangladesh, one of the world's most densely populated countries
Rapid Population Growth - Key takeaways
- Rapid population growth began in the 1800s when people found ways of producing more food and controlling diseases. The global rate is growing at one billion every 15 years at present.
- Population growth is affected by changes in birth rate, death rate, and migration.
- There have been case studies such as the one-child policy in China to control the birth rate; however, it was unsuccessful due to the forced termination of pregnancies and the imbalance of genders.
- Although the countries can get wealthier through rapid population growth, they often cannot provide enough housing or services for education and health as it struggles to keep up with the pace of growth. This shows how rapid population growth impacts socioeconomic development.
- There are many negative consequences for the environment due to rapid population growth, such as pollution and waste, over-extraction, and overpopulated spaces.
References
- Fig. 1: A historical graph of global population growth ( https://en.wikipedia.org/wiki/World_population#/media/File:World-population-1750-2015-and-un-projection-until-2100.png) by Nicxjo (https://commons.wikimedia.org/w/index.php?title=User:Nicxjo&action=edit&redlink=1) Licensed by CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/)
- Fig. 2: Map showing global fertility rates in 2021 (https://en.wikipedia.org/wiki/File:Countriesbyfertilityrate.svg) by Supaman89 (https://commons.wikimedia.org/wiki/User:Supaman89) Licensed by CC BY-SA 3.0 (https://creativecommons.org/licenses/by-sa/3.0/deed.en)
- Fig. 3: A ceramic mural of the one-child policy in China (https://commons.wikimedia.org/wiki/File:PlannedBirthCeramicPaintings-Xinhui.jpg) by Clpro2 (https://commons.wikimedia.org/w/index.php?title=User:Clpro2&action=edit&redlink=1) Licensed by CC-BY-SA-3.0 (https://commons.wikimedia.org/wiki/Category:CC-BY-SA-3.0)
- Fig. 4: Nilkhet Mor in Dhakar in Bangladesh (https://en.wikipedia.org/wiki/File:Nilkhet_Mor_in_Dhaka_by_Nahid_02.jpg) by Nahid Rajbd (https://commons.wikimedia.org/wiki/User:NahidHossain) Licensed by CC BY-SA 4.0 (https://creativecommons.org/licenses/by-sa/4.0/deed.en)
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