3.2.3.2 - Urban forms, land use and new landscapes

Urban form in contrasting settings

Urban form describes the arrangement of buildings, routes, open spaces and activities across an urban area.

Megacities often have extensive built-up areas, many employment centres and infrastructure working across administrative boundaries. World cities contain command functions, international transport nodes and expensive business districts. Neither category guarantees a uniform skyline: planned apartments, informal housing, industrial zones, suburban estates and historic centres can coexist in very large cities. Income, tenure, governance and development history help explain these contrasts.

Relief can constrain expansion and concentrate development in valleys; rivers provide transport and amenity but introduce flood risk and crossings. Coastlines and wetlands constrain usable land. Human factors include historical street layouts, landownership, transport investment, planning controls and segregation. Accessibility attracts businesses that can pay high rents, while space-demanding industries favour peripheral plots. These influences interact: a waterfront becomes developable only if access, ownership, contamination and flood management are resolved.

Salford district combines a redeveloped dock waterfront at the Quays, older inner neighbourhoods, suburban areas and open land to the west. Detroit municipality contains a concentrated downtown but extensive lower-density residential fabric and vacant parcels. These are contrasting high-income post-industrial settings, not a universal model of a wealthy city and a poor city.

Land-use patterns and evidence

Land-use patterns reflect competition for accessibility and space, but simple rings are only starting models.

Central business districts concentrate shops and offices where routes converge. Housing may sort by price, housing age and access; industries can follow railways, rivers or motorway corridors. Multiple nuclei arise around airports, universities and suburban centres. Planning can preserve green space or separate incompatible uses, while informal occupation may develop where formal housing supply fails. Real patterns contain exceptions and change through time.

For an original training transect, suppose five adjacent plots contain offices, flats above shops, a warehouse, a park and a vacant factory. Record mixed use explicitly rather than forcing every plot into one category. A satellite image reveals roofs and open spaces but cannot reliably identify upper-floor functions, tenure or safety. Combine dated imagery with a land-use survey and planning records. Keep plot, neighbourhood and city boundaries separate; an empty riverside plot cannot establish city-wide decline.