Theme 1: Population and Settlement – 1.4 Population Density and Distribution

Hello Geographers! This chapter is all about figuring out a fundamental question: Why do people live where they live? We’ll explore how crowded different places are, and the physical and human reasons behind these patterns. This topic is vital for understanding settlements and resource management globally.

Key Concepts: Density vs. Distribution

It is crucial not to mix up these two terms. They sound similar, but they describe different geographical patterns:

1. Population Distribution (The Pattern)

This describes how the population is spread out across an area or the world.

  • If people are gathered in specific spots (like cities), the distribution is uneven or clustered (or nucleated).
  • If people are spread out thinly across the land, the distribution is sparse or dispersed.

2. Population Density (The Measurement)

This describes how crowded an area is. It is usually calculated as the number of people per square kilometre (km²).

How to Calculate Population Density:

\( \text{Population Density} = \frac{\text{Total Population}}{\text{Total Land Area (km}^2\text{)}} \)

Example: If a country has 1 million people and covers 10,000 km², the density is 100 people per km².

Key Takeaway: Distribution is about where the crowds are; Density is about how big those crowds are relative to the space available.

Factors Influencing Population Density and Distribution

Population patterns are not random! They are influenced by a combination of factors. To remember these, think of the P.E.S.P. framework: Physical, Economic, Social, and Political factors.

1. Physical Factors (The Natural Environment)

These factors usually act as constraints (making settlement difficult) or opportunities (making settlement easy).

  • Relief and Topography:
    • Attracts: Lowlands and flat land (plains or plateaus) are easier to build on, farm, and construct transport links (roads, railways).
    • Repels: Mountains and steep slopes (highlands) have thin, poor soil, are difficult to access, and the climate is harsher.
    Analogy: It’s much easier to build a house on a flat lawn than on the side of a pyramid!
  • Climate:
    • Attracts: Moderate, temperate climates (mild winters, warm summers) or climates with reliable rainfall are ideal for farming and comfort (e.g., Western Europe, coastal China).
    • Repels: Climate Extremes. This includes very cold climates (*Siberia*), very hot and dry climates (*Sahara Desert*), or extremely wet areas (*parts of the Amazon*).
  • Soils and Resources:
    • Attracts: Areas with fertile soil (like river floodplains or areas near past volcanic activity) are excellent for agriculture and supporting large populations (e.g., the Ganges Delta, India). Also, areas rich in valuable resources (coal, oil, timber) attract industry and population.
    • Repels: Areas with infertile or waterlogged soil (e.g., swamps or arctic Tundra).
  • Water Supply:
    • Attracts: A reliable supply of fresh water (near rivers or lakes) is essential for survival, farming, and industry.
    • Repels: Drought-prone areas or areas far from fresh water sources.

2. Economic Factors (Jobs and Income)

These factors usually explain clustering in certain locations, often overcoming physical disadvantages.

  • Employment Opportunities: Areas with thriving primary (mining, farming), secondary (manufacturing), or tertiary (services, finance) industries draw people looking for work.
  • Industry and Trade: Places that are historically important for trade, such as coastal areas with natural harbours or major river junctions, grow quickly and become densely populated (e.g., major port cities like Hong Kong or Singapore).
  • Infrastructure: Good transport networks (rail, roads, ports) and access to energy (power plants) boost economic activity and population growth.

3. Social Factors (Quality of Life)

  • Social Amenities: People want to live near good services, such as schools, hospitals, and cultural centres. These are usually concentrated in urban areas, increasing density there.
  • Historical Reasons: Some areas have high density simply because people have lived there for centuries, passing down land and tradition (e.g., old farming regions in Europe or Asia).
  • Quality of Housing and Safety: Areas with good quality, affordable housing and low crime rates are more attractive.

4. Political Factors (Government Influence)

Government decisions can dramatically alter population patterns.

  • Stability and Peace: Areas with stable, peaceful governments and effective rule of law attract people. Areas suffering from war or political persecution experience population decline (migration/refugees).
  • Policies and Investment: Governments may actively promote settlement in certain regions through investment (building infrastructure) or offering subsidies. Alternatively, they may restrict settlement in protected areas.
    Did you know? In the 20th century, Brazil decided to move its capital inland from Rio de Janeiro to Brasília to encourage development and settlement in the country's interior.

Case Study Examples: Contrasting Areas (Required Content)

The syllabus requires you to know examples of both a densely populated area and a sparsely populated area, and the reasons for their characteristics.

Case Study 1: A Densely Populated Area (e.g., Bangladesh)

Bangladesh has one of the highest population densities in the world (around 1,300 people/km²).

  • Physical Reasons (Opportunities):
    • It is dominated by the delta of the Ganges and Brahmaputra Rivers, providing vast areas of flat, fertile alluvial soil.
    • The monsoon climate provides reliable, heavy rainfall ideal for growing rice, a staple crop that supports a huge population.
  • Economic/Social Reasons (Opportunities):
    • The large, flat area allows for extensive farming (agriculture supports millions).
    • Lack of widespread industrialisation means people remain concentrated in villages and towns in the fertile plains, rather than moving to less hospitable areas.
  • Constraint Note: Despite the high density, the country faces massive challenges from flooding (as it is a low-lying delta) and population pressure on resources.

Case Study 2: A Sparsely Populated Area (e.g., Siberia, Russia)

Large parts of Siberia, Russia, have a population density of less than 1 person/km².

  • Physical Reasons (Constraints):
    • Extreme Climate: The region experiences extremely cold, long winters and low precipitation. Temperatures can drop below -50°C.
    • Permafrost: The ground is permanently frozen (permafrost), making construction extremely difficult, expensive, and unstable. It also restricts farming and natural vegetation growth (taiga forest).
    • Poor Accessibility: The vast distances and harsh climate make building and maintaining transport links (roads, rail) very challenging and expensive.
  • Economic Reasons (Limited Opportunity):
    • While Siberia is rich in oil, gas, and minerals, resource extraction is capital-intensive (needs lots of money/machinery) but requires very little labour, meaning few permanent jobs are created.
  • Political Factors: Historically, the Soviet government did try to force settlement in some areas, but these efforts often failed due to the extreme physical challenges.
Quick Review Box: PESP Factors Summary

Don't worry if this seems like a lot! Just remember the P.E.S.P. categories and pick one good example for each.

Physical: Relief (flat land), Climate (mild), Soil (fertile), Water (available).
Economic: Jobs (Industry), Transport (good accessibility), Resources (raw materials).
Social: Services (hospitals, schools), Safety (peaceful).
Political: Stability, Government Investment/Policy.