Factors that influence the rate of population change Learning Intentions
In this section, you will learn: zz
Agricultural Revolution
about the factors that influence the rate of population change in a country.
Potato blight Baby boom Civil war
Healthcare NUMERACY ACT VITY
Find out if the birth rate is increasing or decreasing in your class. (a) Ask the students in the class how many siblings are in their family. (b) Ask students how many brothers and sisters their parents or guardians have. (c) Compare the figures and see if there is a drop in family size. List any reasons why this might be happening.
A number of factors influence the rate of population change. These include: Health
Food supply War Technological development
Food supply
A growing population needs an increasing food supply. The Agricultural Revolution brought about population growth because it made more food available. Machinery and new farming practices allow farmers to produce more food. Fertilisers and pesticides allow farmers to grow more crops which means that there is more food available and less chance of famine. This lowers the death rate and the population grows.
Before the potato blight in Ireland, the population was growing because of the constant food supply. However, being so dependent on one food source caused a famine, as most of the population had nothing to eat. People died of starvation and emigrated during the Great Famine in the 1840s. This caused the population to drop.
In countries such as Sierra Leone in West Africa, the population is vulnerable to diseases because many people don’t get the necessary nutrition from their food sources. In Sierra Leone, nearly half the population is without a regular food supply.
Education The place of women in society
Sanitation
Life expectancy Family planning
Infant mortality rate
: Figure 18.3 Spraying fertiliser on a bean crop in Australia
