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Urbanization & Services AP Human Geography

Terms in this set (50)

The biggest physical problem is the poor conditions of housing, most of which was built before the 1940s. The poor conditions of housing happens through the process of deterioration. This process has two steps: filtering and redlining.

Filtering: subdivision of houses and occupancy by successives waves of lower-income people. Landlords stop maintaining housing when rent becomes too low, so the property becomes unfit for occupancy. Eventually not even the poorest families can rent a house. Cities have codes that require landlords to maintain the housing, but landlords refuse to do so because the rent doesn't cover it. Because of filtering, many low-income families leave the inner-city and move to less deteriorated housing farther from the center.

Redlining: banks draw lines on a map to identify areas in which they refuse to make loans. This is illegal. This affects families who try to fix up houses because they have trouble borrowing money. The Community Reinvestment Act requires U.S. banks to document where they make loans.

Another physical problem is urban renewal. This consists of public and renovated housing.

Public Housing: is reserved for low income families who pay 30% of income for their rent. It accounts for less than 2% in overall housing, but is higher in the inner-cities. The U.S. government has stopped funding the constructoin of new public housing. But some federal support is available to renovate older buildings and help low income families pay their rent.

Renovated Housing: is an alternative to demolishing deteriorated inner-city houses. This involves gentrification, which is the process by which middle class people move into deteriorated inner-city neighborhoods and renovate the housing. In cities where gentrification is strong, ethnic patterns are being altered and attracts middle class individuals. This affects low-income families because they have to move due to rent that is suddenly too high. Cities try to help low-income families that have to move by reimbursing moving expenses and rent increases over a 4 yr period.
Another model that is fundamental to thinking of urban geography is the so-called rank size rule or the hierarchical model. This model basically says that cities can be all put into one system based on their size, so that the largest city is ranked number one and so on down to the smallest city. When this is done on a graph, you see two or three types of city systems, including the primate city, where the graph steeply falls away from the first rank, and the more advanced urban systems, where the relationship between population and size is more of a straight line.

Comparative Models of Internal City Structure Urban geography really consists of two branches. One focuses on the internal structure of cities, and the other focuses on where the cities are located. Discussions of internal spatial structure have been dominated by a series of models that are usually called classical models, and they are based on the work done by scholars at the University of Chicago in the first years of the 20th century. The first one is called the Concentric Zone Model; the second, the Sector Model; and third, the Multiple Nuclei Model. You see a variety of drawings of these models in the textbooks, and they are actually somewhat contradictory because a variety of subsequent authors have redrawn them. So, it is important not to have your students too fixated on these drawings. Make sure they understand how the models have been developed and what they mean for the future.

All the models are based on the notion of ecology and the notion of competition among land uses. They use the biological models of succession and invasion, meaning that when one land use invades another, it will grow and flourish and replace the land use that it invaded. This can also be thought of as segregationist land use, meaning that the "land uses" want to be separate and not integrated. The problem with these kinds of models is that they cloud the fact that land uses are the result of human decision-makers and regulations; they are not the result of impersonal competition as biological models of community development suggest. They are useful because they help the students understand how cities are shaped, but they also have some danger in that they make students believe that there are no alternatives to the models. In fact, recent developments in cities have shown that the models have some serious flaws; or rather that using the models naively can produce some serious misconceptions about the future of a city. Unfortunately, most textbooks do not present a model-based MCP to go along with these models. Students have to wait until they take an urban geography course to see how cities structure around central places rather than land use zones. Time should be spent on these models, but make sure students understand the principles underpinning them.

Central Place Theory


Walter Christaller developed the Central Place theory to explain the size and spacing of cities that specialize in selling goods and services.
The theory consists of two basic concepts:
1) threshold -- the minimum market needed to bring a firm or city selling goods and services into existence and to keep it in business
2) range -- the average maximum distance people will travel to purchase goods and services







Concentric Zone Model

In 1925, Burgess presented a descriptive urban land use model, which divided cities in a set of concentric circles expanding from the downtown to the suburbs. This representation was built from Burgess' observations of a number of American cities, notably Chicago, for which he provided empirical evidence. The model assumes a relationship between the socio-economic status (mainly income) of households and the distance from the CBD. The further from the CBD, the better the quality of housing, but the longer the commuting time. Thus, accessing better housing is done at the expense of longer commuting times (and costs). According to this monocentric model (see above figure), a large city is divided in six concentric zones:

Zone I: Central Business District (CBD) where most of the tertiary employment is located and where the urban transport infrastructure is converging, making this zone the most accessible.
Zone II: Immediately adjacent to the CBD a zone where many industrial activities locate to take advantage of nearby labor and markets. Further, most transport terminals, namely port sites and railyards, are located adjacent to the central area.
Zone III: This zone is gradually been reconverted to other uses by expanding manufacturing / industrial activities. It contains the poorest segment of the urban population, notably first generation immigrants living, in the lowest housing conditions.
Zone IV: Residential zone dominated by the working class and those who were able to move away from the previous zone (often second generation immigrants). This zone has the advantage of being located near the major zones of employment (I and II) and thus represents a low cost location for the working class.
Zone V: Represents higher quality housing linked with longer commuting costs.
Zone VI: Mainly high class and expensive housing in a rural, suburbanized, setting. The commuting costs are the highest. Prior to mass diffusion of the automobile (1930s), most of these settlements were located next to rail stations.
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According to Burgess, urban growth is a process of expansion and reconversion of land uses, with a tendency of each inner zone to expand in the outer zone. On the above figure, zone II (Factory zone) is expanding towards zone IV (Working class zone), creating a transition zone with reconversion of land use. Although the Burgess model is simple and elegant, it has drawn numerous criticisms:

The model is too simple and limited in historical and cultural applications up to the 1950s. It is a product of its time.
The model was developed when American cities were growing very fast in demographic terms and when motorized transportation was still uncommon as most people used public transit. Expansion thus involved reconversion of land uses. This concept cannot be applied in a contemporary (from the second half to the 20th century) context where highways have enabled urban development to escape the reconversion process and to take place directly in the suburbs.
The model was developed for American cities and has limited applicability elsewhere. It has been demonstrated that pre-industrial cities, notably in Europe, did not at all followed the concentric circles model. For instance, in most pre-industrial European cities, the center was much more important than the periphery, notably in terms of social status. The Burgess concentric model is consequently partially inverted.
There were a lot of spatial differences in terms of ethnic, social and occupational status, while there were low occurrence of the functional differences in land use patterns. The concentric model assumed a spatial separation of place of work and place of residence, which was not generalized until the twentieth century.
However, the Burgess model remains useful as a concept explaining concentric urban development, as a way to introduce the complexity of urban land use and to explain urban growth in American cities in the early-mid 20th century.
Implicit assumptions of Burgess, Hoyt, and Harris and Ullman's models of
urban structure in common
A. Their implicit assumptions are:
1) Great variation in characteristics e.g. heterogeneity of the population in culture and society.
2) Competition for centrality because of limited space leading to highest land value. The opposite is true of peripheral areas.
3) City centre being centre of employment.
4) Commercial and industrial base to the economy of the city.
5) Private ownership of property and capitalist mode of competition for space.
6) Expanding area and population of the city by invasion and succession.
7) No historic survival in any district to influence the land-use pattern.
8) No districts being more attractive because of differences in terrain.
9) Hierarchical order of land use.

B. The Concentric, Sector models and multiple nuclei models have many features in common:
1) Both models focus on importance of accessibility. The centrally located C.B.D. is the most accessible and its land value or rent-bid is the highest.
2) Distant decay theory is applicable in both models. Land value and population density decline with distance from the central places.
3) There are clear-cut and abrupt boundaries between the land-use zones.
4) Both concern the study of ground-floor functions instead of the three-dimensional study as height of buildings is neglected
5) Residential segregation

Social-economic status segregates residential areas. The lower-income groups live in the inner city which is suffering from urban decay or in areas near the factory zone. Nearness to working places reduces time and cost of transport, but gives better working opportunities and easiness of obtaining various order of goods and services. In contrast, the higher-income groups occupy the urban periphery with better living environment far away from the factory zone and the lower-income groups.

C. Difference among Concentric and Sector models
1) concentric model with circular pattern of land use zones; while sector model with sectoral pattern of land use zones
2) land use zones in sector model developed along transport routes radiating out from CBD; while concentric model never mention the transport development
3) sector model emphasizes the repelling forces of land uses; but concentric model concerns the invasion, succession forces on the pattern of the land use

D. Difference among Concentric, Sector and Multiple nuclei models
1) monocentric - concentric, sector model; polycentric - multiple nuclei
2) multiple nuclei more complex in term of land use zones, e.g. industrial suburbs
3) multiple nuclei allows the suburbanization, transport development, outward growth of city
4) multiple nuclei model gives the idea of land use pattern of a city only

Criticism of the models with illustration of the examples
A. A number of criticisms have been leveled on the three models. They include
the following:
1) Negligence of height of buildings.
2) Non-existence of abrupt divisions between zones.
3) Each zone displays a significant degree of internal heterogeneity and not homogeneity.
4) Unawareness of inertia forces.
5) No consideration of influence of physical relief and government policy.
6) The concepts may not be totally applicable to oriental cities with different cultural, economic and political backgrounds.

B. Disturbance of land-use pattern by physical and historical elements and
modern development
1) Impact of physical elements
a. The shape, expansion and land-use zoning of a city are much affected by physical elements.
b. Hilly areas are unattractive to economic functions because of transport difficulties, e.g. Tai Mo Shan in Hong Kong but may attract some cottage housing because of cheaper land value
c. Some luxurious housing on site with good view, e.g. the Mid-level on Hong Kong Island
d. Water-front location provides easy accessibility and attract water transport facilities, e.g., Kwai Chung Container Terminal and port industries
e. High-income housing e.g. Discovery Bay exists for their scenic value.

2) Impact of historical elements
Cities with a long history of development;
a. e.g. Beijing with Royal Place and Altar of Heaven,
b. e.g. Rome with Vatican as religious centre and cities with colonial history
c. e.g., Manila has mixed land-uses rather than clear-cut land-use zones.
The mixed land-use zones may consist of commercial, industrial, residential, cultural, religious and administrative functions instead of one single function.

3) Impact of modern developments
a. Improvements of transportation, innovation of technology and government policy have altered the land-use patterns of the models. Industrial estates, commercial buildings and offices may locate at different parts of the city
i. e.g. Tai Po and Yuen Long Industrial Estates are widely separated
ii. e.g., a commercial complex at Discovery Bay
b. Polycentric patterns replace mono-centric ones as a result of multi-nuclei development in the new towns with secondary commercial centres, industrial and residential suburbs.
c. Under urban renewal programmes, the old shanty parts of the urban area are replaced by tall modern buildings.
d. While suburbanization engulfs towns and merges cities in the neighbourhood to form an extensive urban area called megalopolis with multiple centres and a complex of land-use zones, e.g. the Bosnywash megalopolis which extends from Boston through New York to Washington D.C. in the northeast seaboard of North America.

Instead, a fused model, in which elements of all three models are present, is more applicable to a modern metropolitan city. In the fused model, there are a central core and several other business districts around which concentric zones develop.
However, they are broken by sectors of radial growth along the main transport arteries that connect the various outlying business districts. The resultant product is a star-shaped city with various distinct functional zones along the axes of growth.

Besides the economic force that produces the star-shaped pattern, there are other factors such as topography, government policy and cultural and social influences with various impacts on the urban development.

In conclusion, the land-use patterns of most cities are a fused model of the key elements of various land-use models.

C. Examples: Hong Kong, Sydney, Chicago (5 marks)