Physical factors affecting population distribution

Climate

• A region's long-term weather patterns measured in terms of factors such as average precipitation, max/min temperatures throughout the seasons, sunshine hours/solar insolation levels, wind speeds and frequency of extreme weather events.
• Tropical, dry, mild, continental and polar.
• Microthermal (cold winters and low evapotranspiration), mesothermal (moderate climate; not cold enough to sustain permanent snow cover but not warm enough to maintain flowering plants all year round) and Megathermal (hot/humid, rich vegetation all year round e.g. the Amazon Basin, Congo Basin).
• Many crops require a minimum temperature of 5C to grow.
• Pasture-fed livestock must be fed with fodder crops when temperatures drop below 5C.
• Influences presence and type of diseases like malaria and yellow fever.
• Monsoon environments are densely populated.
• To some extent determined by topography/relief/altitude.

Geology and soils

• Soils
• Fertility depends on structure, texture, acidity and levels of humus and nutrients
• This affects the type of agriculture and species used
• Areas with fertile soils = densely populated as they allow for more crops to be grown and can be exploited more as they have more nutrients; fertilisers do not have to be used
• Volcanic soils
• Alluvial soils
• Associated with natural hazards
• 59% of Bangladesh is marked as arable land, as well as construction of dams since 1960s leading to silt deposits
• Fertility may be maintained using artificial fertilisers where soils have been overused/deserted over time
• Water pollution
• Eutrophication
• Increased GHG emissions
• Geology
• Lots of natural resources like fossil fuels = densely populated
• E.g. Saudi Arabia
• Provides good economic income and promotes development
• Even when local resources become depleted there will likely be newer tertiary or quaternary industries to maintain the community

Water supply

• Essential for everyday life - drinking, cooking, washing, sanitation, hygiene, irrigation
• E.g. in the Ganges river valley.
• Contaminated water supply leading to water-borne diseases such as malaria.
• If this is in LIC then people will not necessarily move out as they cannot afford to.

Ecosystems, vegetation and wildlife

• Densely vegetated areas like the Amazon rainforest are unlikely to be densely populated as it is difficult to build on this land and it would be difficult to get planning permission
• Very remote

Topography, relief and altitude

• HIgh mountains - uninhabited due to harsh conditions
• Steep slopes
• Non-arable land
• Harsh conditions
• Inaccessible
• Foothills of mountains/land surrounding mountains likely to be densely populated
• Arable and fertile land
• Still sufficient precipitation but not the same harsh conditions as are at higher altitudes
• Good vegetation to graze animals
• More accessible
• People tend to live in valleys - e.g. Japan

Natural hazards

• Less of an impact than other factors as communities are resilient and able to adapt to live with them.
• E.g. use of advanced technology in Japan.

Population parameters

• Physical features
• Water supply, e.g.
• Development, especially in LICs and NEEs
• Neolithic Agrarian Revolution - 12,000 years ago
• Industrial Revolution - Europe, 17-1800s
• Lead to technological developments which can then support larger populations
• Increasing ability to control infectious diseases - main reason for population explosion from 1 billion to 7 billion 1800-2011
• Population density
• Water supply
• Resource distribution
• Population sparsity
• Deserts
• Continental interiors
• Extreme cold

Population parameter - example

• The River Nile:
• Very high population density in the Nile Delta and Nile Valley even though these only account for 5% of Egypt's total land area
• Upstream - population distribution follows patterns of rainfall
• Ethiopian Highlands
• Nile Equatorial Lakes Plateau
• Over 95% of the population live along this fertile strip
• 150 people per km2
• Compared to 80 per km2 in the rest of Egypt (excluding desert areas)