Changing population - Population distribution + density Flashcards
Where is the explosion in population growth happening?
Up to 95% of population growth is happening in developing countries
How many people are born each second and each year?
- 2 extra people each second
- 80 million new births per year
Where will the greatest increases take place?
In the least developed nations:
- Afghanistan’s population will double
- Niger’s population will triple
What are the temporal + Spatial patterns of population?
-Temporal = change over time
- Spatial = change or variation over space (across a geographical area)
What is population distribution?
A description of the way in which people are spread out across the earth’s surface
- Where people live
- Even/uneven distribution
What is population density?
The number of people occupying a specific area (people per sq km)
- Sparse/dense population
Why is the global population described as unevenly distributed?
Because over 50% of people are on just 5% of the land
Why is this trend of uneven distribution of the population increasing?
Because more and more people are living in urban areas, over half the world’s population
- 21 megacities
- 2008 tipping-point urban-rural
Why are there large unpopulated areas?
Due to their climate
- continental interiors = often extreme environments -> too hot, dry, cold, wet, steep
Where are three major concentrations of populations found?
- S.E. Asia
- W. Europe
- N.E. USA
Where are three other types of areas where large population concentrations are found?
- Coastal areas (75% within 1000km of sea)
- 80% in N. Hemisphere (most in temperate zone, between 20-60 degrees north)
- 85% live in low-lying areas (0-500m above sea level)
What are the physical factors that affect population density?
- Physical accessibility
- Relief + soils
- Climate
- Vegetation
- Water supply
How does the physical factor of physical accessibility affect population density
- Sparse population: Rugged mountains (Alps) or High plateaux (Tibet)
- Dense population: Flat lowlands (Netherlands or Nile valley)
How does the physical factor of relief + soils affect population density?
- Sparse population: Frozen soils (Siberia) or Eroded soils (Sahel)
- Dense populations: Deep humus (Paris basin) or River silt (Ganges delta)
How does the physical factor of climate affect population density?
- Sparse population: Low temperatures (Canada or Alaska)
- Dense population: Longer growing season (tropical Asia)
How does the physical factor of vegetation affect population density?
- Sparse population: Dense forest which restricts human activity
- Dense population: Grassland ecosystems (Eastern Europe)
How does the physical factor of water supply affect population density?
- Sparse population: Insufficient or unpredictable supply (Australian desert)
- Dense population: Mostly reliable all-year supply (Western Europe)
What are the human factors that affect population density?
- Economic factors
- Political factors
- Technological factors
How does the human factor of an economic factor affect population density?
- Sparse population: Extensive agriculture (few workers needed per unit area)
- Dense population: Ports (Singapore) or Intensive farming (China)
How does the human factor of a political factor affect population density?
- Sparse population: Low levels of state investment (interior of Brazil)
- Dense population: Forced movements (Soviet settlement of Siberia)
How does the human factor of a technological factor affect population density?
- Sparse population: Lack of technology needed to increase water availability
- Dense population: Irrigation and desalinisation technologies available