6.3 The changing structure of urban settlements

• the concentric zone


  A region of an urban area, circular in shape, surrounding the CBD and possibly other regions of a similar shape, that has common land use/socio-economic characteristics.
• CBD

  Central Business District
• Concentric zone model


  A model of the internal structure of cities in which social groups are spatially arranged in a series of rings.

  
• Main assumptions upon which the model were based

  A uniform land surface

  Free competition for space

  Universal access to a single-centred city

  Continuing in-migration to the city, with development taking place outwards from the central core
• E.W Burgess


  a sociologist who made the concentric zone model
• Zone in transition

  the area just beyond the CBD, which is characterised by a mixture of residential, industrial and commercial land use, tending towards deterioration and blight. The poor quality and relatively cheap cost of accommodation makes this part of the urban area a focus for in-migrants, resulting in a rate of population change higher than in other parts of the urban area.
• Zone of working-men's homes


  Characterised by some of the oldest housing in the city and stable social groups- beyond zone of transition
• Residential zone


  Occupied by the middle classes, with its newer and larger houses
• Commuters' zone


  the outermost zone of the concentric zone model that represents people who choose to live in residential suburbia and take a daily commute into the CBD to work- extended beyond the built- up area
• Bid-rent theory


  decreasing accessibility as you move out from the centre of an urban area, with corresponding declining land values, allowing an ordering of land uses related to rent affordability

  
• Creator of the Bid Rent Theory

  William Alonso
• A sector


  a section of a urban area in the shape of a wedge, beginning at the edge of the CBD, and gradually widening to the periphery.
• Sector Model


  A model of the internal structure of cities in which social groups are arranged around a series of sectors, or wedges, radiating out from the central business district (CBD).

  
• Creator of sector model

  Hoyt
• mutiple nuclei model


  A model of the internal structure of cities in which social groups are arranged around a collection of nodes of activities.

  
• Creators of the multiple nuclei model

  Harris and Ullman
• Latin American City Model

  Griffin-Ford model. Developed by Ernst Griffin and Larry Ford. Blends traditional Latin American culture with the forces of globalization. The CBD is dominant; it is divided into a market sector and a modern high-rise sector. The elite residential sector is on the extension of the CBD in the "spine". The end of the spine of elite residency is the "mall" with high-priced residencies. The further out, less wealthy it gets. The poorest are on the outer edge.

  
• Urban density gradient


  the rate at which population density and/or the intensity of land use falls off with increasing distance from the centre of the city
• Gradient analysis of cities in HICs over time shows

  The initial rise and later decline in density of the central area

  The outward spread of population and the consequent reduction in overall density gradient over time
• Gradient analysis of cities in LICs and MICs over time shows

  A continuing increase in central area densities

  The consequent maintenance of fairly stable density gradients as the urban area expands
• Factors affecting the location of urban activities

  Market forces- demand and supply of land

  Local or central government planning decisions- planners can overrule market forces
• Examples of urban activities

  Retailing, manufacturing, open space
• Constrained location theory


  Identifies the problems encountered by manufacturing firms in congested cities, particularly in the inner areas
• Deindustrialisation


  the long-term absolute decline of employment in manufacturing
• Post-industrial city


  A city whose economy is dominated by services and new high-tech industries.
• Inner-city decline


  The deterioration of the inner city often caused by lack of investment and maintenance
• Explanation for inner city decline

  The industrial buildings of the 19th and early 20th century, mostly multi-storey, are generally unsuitable for modern manufacturing

  The intensive nature of land use usually results in manufacturing sites being hemmed in by other land users, thus preventing on-site expansion

  The size of most sites is limited and frequently deemed to be too small by modern standards
• Retailing


  all the activities directly related to the sale of goods and services to the ultimate consumer for personal, non-business use
• Outside CBD- urban areas have witnessed development of...

  Suburban CBDs

  Retail parks

  Urban superstores

  Out-of-town shopping centres

  Internet shopping and home delivery services
• Rural-urban fringe


  the boundary zone where urban and non-urban land meet, and an area of transition from agriculture and other rural activities to urban use
• Common changes in CBDs

  Pedestrianised zones

  Indoor shopping centres

  Environmental improvements

  Greater public transport coordination

  Ring roads around the CBD with multi-storey car parks
• Key features of the CBD

  
• Residential segregation


  the degree to which two or more groups live separately from one another, in different parts of an urban environment
• Residential mosaic


  The complex pattern of different residential areas within a city reflecting variations in socio-economic status that are mainly attributable to income, but also influenced by ethnicity and age
• Gentrification


  a process in which wealthier people move into, renovate and restore run-down housing in an inner city or other neglected area
• Reasons for residential segregation

  Income, race/ethnicity, operation of the housing market, influence of family and friends and culture and planning
• Urban renaissance


  Recent period of repopulation and regeneration of many British cities following period of inner city urban decay and suburbanisation
• Advantages of gentrification

  -The neighborhood becomes nicer

  -property values increase, which increases the tax base for the city

  -More services (retail, restaurants) come to the neighbourhood
• Disadvantages of gentrification

  people on lower incomes can't afford the higher property prices/rent

  incomers may be seen as a threat

  loss of business for original low order services