Urban Surface

A urban surface is a geographical concept used in Urbanisme. The definitions and names of an urban surface, zone occupied primarily by constructions (of dwelling and economic activity and administrative), vary according to the countries. One speaks about transborder Agglomération if this urban surface extends beyond the border from a country or a state.

Definitions

The definitions of the statistical institutes of the various countries use different definitions to express similar concepts (nonexhaustive list):

the the United States use the term of metropolitan area (“metropolitan surface”), whose definition varied during the last censuses, but which includes an agglomeration and the peripheral zones which are dependant for him from the professional and commercial point of view.
the term urban area (literally “urban surface”, urbanized area in the United States) is also used by several Anglo-Saxon countries:

In the United States, it acts of a group of units of census of one population density at least: 1000 inhabitants per square mile and adjacent units of a density of at least 500 inhabitants by square miles.
In Australia, the minimal density is fixed at 200 inhabitants per km ².
With the Canada and the the United Kingdom, it acts of zones whose difference between dwellings does not exceed 200 Mr.

With the Portugal, the tipologia of Áreas Urbanas , established in 1998 and applied since 2000 by the national statistical office (INNATE) and the Head office of Town and country planning and Development Urbain (DGOTDU), establishes “surfaces with urban prevalence” (APU) on the basis of Freguesia S. the APU are delimited on minimal criteria of size (: 5000 agglomerated inhabitants), of density (500 inhabitants per square kilometer) or of growth of the population of the freguesia, but also according to the administrative offices of the locality or its vicinity of another freguesia urban. The APU gather 68% of the Portuguese population thus.
In Slovenia, the urban surfaces gather since 2003 an urban pole ( mestna naselja ), i.e. one or more localities selected according to their size, of their administrative role and/or an excess of by-report/ratio employment to the number of the credits resident, as well as localities under urban influence ( naselja in mestnih obmocjih ), i.e. located near a pole of: 5000 inhabitants and more, with a pendular proportion of significant and a limited number of farms. One counts 104 urban surfaces thus gathering 49,5% of the Slovenien population.
In Austria, since 1975, the Stadtregionen (urban areas) consist of a central pole, called Kernraum , gathering: 15000 inhabitants at least in zones whose difference between dwellings does not exceed 500 m, as well as the communes of which at least 30% of the population resident active work in the central pole. One counts 39 urban areas gathering 5,2 million inhabitants, either 65,8% of the Austrian population in 2000.
In France, a urban surface is precisely defined like the unit consisted a urban Pôle (agglomeration offering at least 5.000 employment) and his Couronne périurbaine in which at least 40% of the active population resident work, or the coarse equivalent of the American metropolitan areas . A Anglo-Saxon urban area approaches more urban Unité French.

Who more is, the basic units on whom are carried out calculations different from one country to another following the division of the territory in force. In the United States, the counties are often used, while in France, the communes fill this office, which generally lead to a finer grid.

Principal urban surfaces in the world

It is difficult to establish comparable data between urban surfaces in the world, the methods of calculating being different from one country to another. It is possible to draw up the following list, starting from estimates going back to 2005:

See too

transborder Agglomeration
urban Surface (France)
List of the principal urban surfaces of Europe
List of the urban surfaces of Italy

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