Lecture 8: The urban transition

Urban growth

Refers to absolute increase in the urban population.

Urbanisation

The process whereby a rising proportion of the population comes to live in urban areas. It is a measure of the proportion of the population living in urban areas (“level of urbanisation”) and the change from rural to urban lifestyle and associated attitudes and values.

Processes of urbanisation in Britain (eighteenth century)

Urban growth in MDR vs LDR

• Of the 2.87 billion population growth 2009-2050, virtually all will occur in the urban areas of LDRs

• The rest will be made up of a small rise in MDR cities and LDR rural areas

• There will be a small decline in MDR rural areas

Urban growth by continent

The significance of cities

• Basis of civilisation

• Engines of economic growth

• Nodes of connections

• Major consumers

• Major producers of waste

• Living environment for half the world’s population

• Main focus of future growth

City

A large, nucleated settlement that is multifunctional in character and includes a CBD, residential and non-residential land use (~2.7 million people).

Urbanised area

Continuous built-up landscape i.e. the physical city (~6.2 million people).

Metropolitan area

Large scale functional entity may contain a number of urbanised areas operating as an integrated economic whole (~6.4 million people).

Defining what is considered urban

• The UN Population Division threshold is 2 000 residents

• There are varied approaches based on:

  • administrative boundaries (108 of 228)

  • settlement size and/or density (51/228)

  • functional characteristics (39/228)

  • no definition (30/228)

Cities (densely populated areas)

These are areas with a high density (at least 1,500 inhabitants per km²) and a large population (at least 50,000 inhabitants).

Towns and semi-dense areas (intermediate density areas)

These are urban clusters outside of cities with a moderate density (at least 300 inhabitants per km²) and a population of at least 5,000 inhabitants. This category includes dense towns, semi-dense towns and suburban or peri-urban areas.

Rural areas (thinly populated areas)

This category includes villages, dispersed rural areas and very dispersed rural areas based on grid cells with a density below 300 inhabitants/km², or denser cells not part of a city, town or semi-dense area.

Sources of urbanisation

• Internal migration (rural-urban)

• International migration

• Natural increase (births-deaths)

• Reclassification of boundaries (annexation) or in-situ urbanisation

Direction of internal migration change with urbanisation

Patterns of internal migration in Australia

• Four major patterns of redistribution

  • from the South and East to the north and west

  • from the inland to major cities

  • from major cities to high amenity coastal regions NSW Melbourne

  • within the cities to the urban fringes, and towards the urban core

• Emigration from Europe as a major source of urban growth in the ‘New World’

• Coastal settlements established around trading ports to export goods produce

International migration

• Immigration (illegal and legal) accounts for one third of urban growth in the MDRs

• Without international migration, the urban population in MDRs is projected to decline

Natural increase

• A key factor in urban growth

• Can also contribute to urbanisation

  • initially death rates are higher in urban areas

  • but fertility is lower than in rural areas

  • generates a population decline in urban areas

  • mortality falls to substantially lower levels – generating return to natural increase in urban areas

• Migration alters population momentum in urban areas as migrants have “superior reproductive value” owing to the selectivity of migration (young adults)

Reclassification of boundaries

Urbanisation in place (in situ) as rural populations grow through natural increase many areas change from rural to urban

Contemporary urbanisation

• More developed countries

  • cities growing by international migration

  • limited rural to urban migration – largely replaced by counter-urbanisation – tree change/sea change

  • kow natural increase

  • some cities shrinking

  • attempts to divert immigration to regional areas

  • depopulation of some rural areas (ageing and out migration)

• Less developed countries

  • high rural to urban flows (“Bright lights”)

  • large rural population feeding urban growth

  • high levels of natural increase

  • attempts to limit population growth in cities by restricting rural-urban migration

  • some population growth syphoned off through emigration

  • urbanisation in situ