Unit 2: Living in Our World — Theme A: Population Growth, Change and Structure
Welcome to your study notes for Population Growth, Change and Structure! Whether you love studying human geography or find it a bit tricky, do not worry — this guide breaks down everything step-by-step with clear definitions, helpful analogies, and key exam tips tailored for your CCEA GCSE Geography exam.
Why study this topic? People make up the world around us. Understanding why populations grow, shrink, or age helps governments plan for schools, hospitals, jobs, and pensions.
---1. Core Population Terms and Calculations
To understand population, geographers look at how many people are born, how many die, and how people move around.
Key Definitions
Birth Rate: The number of live births per \(1,000\) of the population per year.
Death Rate: The number of deaths per \(1,000\) of the population per year.
Migration: The movement of people from one place to another to live or work.
Measuring Population Change
A population changes naturally through births and deaths, but overall change also includes migration.
Natural Increase: This happens when the birth rate is higher than the death rate.
\(\text{Natural Increase} = \text{Birth Rate} - \text{Death Rate}\)
Natural Decrease: This happens when the death rate is higher than the birth rate.
\(\text{Natural Decrease} = \text{Death Rate} - \text{Birth Rate}\)
Actual Population Change: To find out the true overall change in a population, we also include people moving in (in-migration / immigration) and people moving out (out-migration / emigration):
\(\text{Actual Change} = (\text{Births} - \text{Deaths}) \pm (\text{In-migration} - \text{Out-migration})\)
The Dependency Ratio
Every country has people who work and pay taxes, and people who rely on others (like school children and retired people). We divide the population into two main groups:
1. Dependents: Young dependents (aged \(0\) to \(14\)) plus elderly dependents (aged \(65+\)).
2. Economically Active: Working-age population (aged \(15\) to \(64\)).
The Dependency Ratio measures the burden placed on the working population:
\(\text{Dependency Ratio} = \frac{\text{Young Dependents } (0-14) + \text{Elderly Dependents } (65+)}{\text{Economically Active Population } (15-64)} \times 100\)
Analogy: Imagine a team rowing a boat. The rowers are the economically active group, while the passengers resting in the boat are the dependents. If there are too many passengers and too few rowers, it becomes very hard to move forward!
Common Examiner Pitfall:
Always remember that Birth Rate and Death Rate are measured per 1,000 people per year, not as total numbers of people. Also, when calculating the Dependency Ratio, make sure the working group (\(15-64\)) is in the bottom (denominator) of your fraction, not the top!
Section Takeaway: Population change depends on births, deaths, and migration. The dependency ratio compares those who cannot work (\(0-14\) and \(65+\)) to those who can (\(15-64\)).
---2. The Demographic Transition Model (DTM)
The Demographic Transition Model (DTM) shows how a country's birth rate and death rate change over time as the country develops economically and socially.
The 5 Stages of the DTM
Stage 1: High Fluctuating
• Birth Rate: High and fluctuating.
• Death Rate: High and fluctuating (due to disease, famine, and lack of medical care).
• Population Growth: Very low and stable.
• Example: No whole country is in Stage 1 today, but some remote tribes live in these conditions.
Stage 2: Early Expanding
• Birth Rate: Remains high.
• Death Rate: Falls rapidly (due to cleaner water, better sanitation, and basic healthcare).
• Population Growth: Very rapid natural increase.
• Example: Afghanistan.
Stage 3: Late Expanding
• Birth Rate: Falls rapidly (due to improved access to contraception, increased female education, and fewer children needed for farming).
• Death Rate: Continues to fall, but more slowly.
• Population Growth: Growth slows down.
• Example: India.
Stage 4: Low Fluctuating
• Birth Rate: Low.
• Death Rate: Low.
• Population Growth: Slow, stable growth.
• Example: United Kingdom, USA.
Stage 5: Decline
• Birth Rate: Falls below the death rate.
• Death Rate: Low, but may rise slightly due to an ageing population.
• Population Growth: Natural decrease (population shrinks).
• Example: Japan, Germany.
Memory Aid for DTM Stages:
• Stage 1 = Both High
• Stage 2 = Death Rate Drops
• Stage 3 = Birth Rate Drops
• Stage 4 = Both Low
• Stage 5 = Birth Rate Drops Below Death Rate
Common Examiner Pitfall:
Do not simply state that rates "go up" or "go down". Always explain why (for example: "Death rates fall in Stage 2 because of improvements in clean water supplies, sanitation, and vaccinations.").
Section Takeaway: As countries develop, death rates drop first due to better healthcare and hygiene, followed later by falling birth rates as education and family planning improve.
---3. Population Structure and Pyramids
A Population Pyramid is a special type of horizontal bar graph that shows the age and gender (sex) structure of a country's population at a specific point in time.
• The vertical axis (up the middle) shows age groups (usually in 5-year bands, e.g., \(0-4\), \(5-9\)).
• The horizontal axis shows the percentage or total number of people.
• Males are traditionally shown on the left, and females on the right.
Comparing LIC and HIC Pyramids
Low-Income Country (LIC) Pyramid (e.g., Stage 2 countries):
• Base: Very wide base, indicating a high birth rate.
• Top: Very narrow top, indicating a low life expectancy and small elderly population.
• Sides: Concave shape (curves inward), showing a high death rate and high infant mortality across age groups.
High-Income Country (HIC) Pyramid (e.g., Stage 4 and 5 countries):
• Base: Narrow base, indicating a low birth rate.
• Top: Wide top, indicating a high life expectancy and large elderly population.
• Sides: Straight or convex shape (bulging outwards), showing a low death rate throughout adulthood.
Linking Pyramid Shapes to Geography Terms:
• Wide base \(\rightarrow\) High Birth Rate
• Narrow base \(\rightarrow\) Low Birth Rate
• Wide top \(\rightarrow\) Long Life Expectancy / Ageing Population
• Narrow top \(\rightarrow\) Short Life Expectancy / High Death Rate in Old Age
Section Takeaway: Population pyramids give an instant visual picture of a country's birth rates, death rates, and life expectancy.
---4. Case Studies: Managing Population Change
CCEA requires you to know detailed case study examples showing how population structure creates challenges and how governments respond.
Case Study 1: An Ageing Population — United Kingdom
The UK is a High-Income Country (HIC) experiencing an ageing population, meaning that the proportion of elderly people is increasing relative to the rest of the population.
Causes of an Ageing Population in the UK:
• Increased Life Expectancy: Advanced medical treatments, vaccinations, healthier diets, and better living conditions mean people live longer into their \(80\)s and \(90\)s.
• Low Birth Rates: Widespread access to contraception, higher costs of raising children, and more women pursuing full-time careers mean fewer babies are born each year.
Impacts and Challenges:
• Healthcare Pressure: Increased demand on the NHS and social care services to treat chronic and age-related illnesses.
• Pensions Crisis: The government must pay out more in state pensions, while having a smaller proportion of working taxpayers to fund them.
• Shrinking Workforce: Fewer young people entering the workforce can lead to labour shortages in key industries.
Case Study 2: Population Policies
Governments introduce population policies to influence the size, growth rate, or structure of their population.
1. Anti-Natalist Policy (Aiming to reduce birth rates):
• Named Example: China's One Child Policy.
• Context & Aim: Introduced historically to prevent rapid population growth and avoid severe food and resource shortages.
• Methods: Strict limits where couples were generally restricted to having one child, enforced through fines and incentives.
2. Pro-Natalist Policy (Aiming to increase birth rates):
• Named Examples: France or Singapore.
• Context & Aim: Introduced in response to falling birth rates, a shrinking workforce, and an increasingly ageing population.
• Methods: Providing financial incentives (such as baby bonuses, subsidised childcare, tax breaks, and generous paid parental leave) to encourage families to have more children.
Section Takeaway: An ageing population puts pressure on healthcare, pensions, and the economy. Governments use anti-natalist policies to slow growth or pro-natalist policies to boost falling birth rates.
---Quick Revision Checklist
Can you answer these key revision questions? Test yourself before your exam!
• Can you state the formula for Natural Increase and Actual Population Change?
• Can you calculate the Dependency Ratio given the number of young, elderly, and working people?
• Can you describe what happens to birth and death rates in each of the 5 DTM stages?
• Can you explain why an LIC pyramid has a wide base while an HIC pyramid has a narrow base?
• Can you name the causes and impacts of the UK's ageing population?
• Can you name one anti-natalist and one pro-natalist policy example?