IB Geography Urban Environments

greenfield site

a piece of land that has not been built on before, but is now being considered for development

urban consolidation

the process of increasing the density of residential buildings in an urban area. Infilling gaps, bringing disused buildings back into productive use, etc.

suburbanisation

outward growth of towns and cities to engulf surrounding villages and rural areas.

suburb

residential areas within or just outside the boundaries of a city

decentralisation

when manufacturing industries and people relocate outwards from the urban center

gentrification

when middle class people move into run down inner city areas with the intention of renovating the old buildings

distance decay

as distance from the PLVI increases, land prices decrease... also reflecting this, building heights decrease.

Burgess Model

land uses are arranged around the CBD in concentric circles, with the profitable uses being found closest to the city center

Multiple Nuclei Model

Argues that land uses tend to be arranged in cells or patches throughout the city depending on the availability and the quality of land

bid rent theory

retailers can afford the highest rents, but they are not prepared to pay high prices if they are not in highly accessible areas

population density hollow

in the CBD residential land use is usually outbid by retailing and office space so the population of the CBD part of the city is low

Hoyt (Sector) Model

based on the circles on the Burgess model, but adds sectors of similar land uses concentrated in parts of the city. Notice how some zones, eg the factories/industry zone, radiate out from the CBD.

Peak Land Value Intersection

the point of the highest land value often resulting from the intersection of communication routes

Megacity

A city with a population of at least 10 million people.

spatial exclusion

a process where wealthy residents become so concerned about their security and defending their luxury lifestyles that special access and freedom of movement becomes restricted

counter-urbanisation

movement of population away from inner urban areas to a new town, a new estate, a commuter town or a village on the edge or just beyond the city limits

ecological footprint

the theoretical measurement of the amount of land and water a population requires to produce the resources it consumes and to absorb its waste under prevailing technology

Brownfield Site

Abandoned or underused industrial buildings and land which may be contaminated but have potential to be redevelopment

Shanty Housing

'Homemade' housing using scavenged materials such as corrugated iron, cloth and plastic.

Squatters

People who have no legal title on the land they live on. The do not rent or own land and will build or live on vacant land, such as nearby railways or on steep slopes.

Urban Decay

Reflects the lack of inner-city demand. Many vacant blocks, derelict buildings, graffiti. It is not a source of employment, tax revenue or income.

Urban Dynamics

The processes operating in an urban area.

re-urbanization

development of activities to increase residential population densities within the existing built-up area of a city.

Urban Growth

Increase in size of an urban area or an increase in the number of people living in an urban area.

Urban Heat Island

Urban areas becoming warmer than their surroundings. Is done by cement retaining heat, car exhausts, pollution fumes, etc.

Urban Renewal

A governmental programme, converting run-down areas into attractive public areas. E.g. London Docklands in Sydney, Australia.

Urban Sprawl

Unplanned and uncontrolled physical expansion of a city into surrounding areas.

Urbanisation

An increasing percentage of a country's population moves into towns and cities. It can be due to migration or natural increase.

Centripetal movement

Movement toward the center. In this case, movement toward the city center.

Centrifugal movement

Movement away from the center. In this case, movement away from the city center.

Circular City System

Inputs come into the city and are recycled in order to reduce the amount of negative outputs like trash and pollution

Linear City System

Inputs come into the city such as people, natural resources and energy and products as well as waste, noise and congestion are the cities outputs.