Distribution and density
Population distribution is the way people are spread across the Earth's surface, while population density is the average number of people per unit area, usually per square kilometre. World population is very uneven: some regions are crowded while others are almost empty.
Key idea
Population density = total population ÷ land area (people per km²). A high figure means a densely populated area; a low figure means a sparsely populated area.
Factors affecting distribution
Physical factors
- Relief — flat lowlands and river plains attract people; steep mountains repel them.
- Climate — moderate, wet climates are favourable; deserts and polar areas are not.
- Soil — fertile soils support farming and dense settlement.
- Water supply — people cluster near rivers, lakes and coasts.
Human factors include jobs and industry, transport links, mineral resources, government policy and historical settlement.
Example
The lowlands and river deltas of eastern China, South Asia and Java are densely populated because of fertile soil and water, while the Sahara Desert, Amazon rainforest and polar regions are sparsely populated.
Densely vs sparsely populated areas
| Dense | Sparse |
|---|---|
| Flat, fertile lowlands | High mountains |
| Mild, wet climate | Deserts, polar climates |
| Many jobs and industries | Few resources and jobs |
Remember
- Distribution = spread; density = people per km².
- Favourable: lowland, fertile soil, mild climate, water, jobs.
- Unfavourable: mountains, deserts, poles, dense forest.