What are the main models of urban ecology

Chicago School


1 Introduction and definition of terms
1.1 Human ecology / social ecology
1.2 Urban ecology
1.3 Urban Ecology

2 The Chicago School
2.1 definition
2.2 Biography: Robert Ezra Park
2.3 The three urban structure models
2.3.1 The Burgess circular model
2.3.2 The sector model according to Hoyt
2.3.3 The multicore model according to Harris and Ullman

3 Criticism of the urban structure models
3.1 Criticism of Burgess and Hoyt
3.1.1 The problem of delimitation
3.1.2 Validity of the models
3.1.3 The vertical factor
3.2 Criticism of Harris and Ullman

4 Summary

5 literature

1 Introduction

The Chicago School is considered to be one of the outstanding phenomena in relation to studies dealing with phenomena in urban ecology. Despite the long distance and the rather old age of the Chicago school, interest in it is still aroused in Germany today. Last but not least, it owes this curiosity that arose here to its founder "Robert Ezra Park", who through his rich journalistic work was not only the mouthpiece of this movement. Park, who among other things also gave various lectures, repeatedly asked his students to join Walking around the city, looking around to get an idea of ​​the existing conditions for yourself.This park idea resulted in a very human view of the living conditions.

Three different "urban structure models" emerged from the Chicago school, which were intended to be used for planning and as an orientation for urban development. All of these urban structure models were first related to Chicago and discussed.

The aim of this work is to help you understand what the term "Chicago School" and the related sub-areas mean. It aims to clarify what "human ecology", "urban ecology" and "urban ecology" mean, and to what extent they relate to the Chicago School are in contact. How it came to the urban structure models specifically, which factors influenced, and why Chicago became the birthplace of this theory will be explained. The founder of the Chicago School, Robert Ezra Park, is to be introduced and his main thoughts interpreted. Finally, criticism of the Chicago school will be examined.

1.1 Definition of the key terms

1.1.1 Human ecology / social ecology

Human ecology emerged from the tension of sociology in the USA, which was still young at the time. It describes how population groups adapt to their environment. "The approach is the basic social science that defines the framework for the investigation of economic, political and moral phenomena." (Lindner 1990: 77) In particular, the human-nature problem is analyzed in human ecology.

This includes understanding that the way people deal with their environment is socially determined, namely in the form of economic, technical or cultural processes. Human ecology researches the approaches to environmental destruction by society and endeavors to develop tactics and economic strategies that are compatible with humans and the environment.

The term social ecology is closely related to the term human ecology. Park and Burgess introduced it to American sociology in 1920 and understood it to mean the relationship between humans and the environment with regard to urban settlement structures.

1.1.2 Urban ecology

,, Urban ecology i. e. S. is that sub-discipline of ecology that deals with urban biotopes, biotopes and ecosystems, their organisms and site conditions as well as with the structure, function and history of urban ecosystems. "(Sukopp et al 1998: 2)

Urban ecology is therefore a sub-discipline of human ecology, as it aims to improve living conditions. For this it is urgently necessary that several sciences from different areas work together. Because only scientific disciplines can no longer cover this broad area. The collaboration of social, cultural and human sciences is increasingly required. In Sukopp et al (1998: 1) the reason is as follows: "People do not adapt to the urban living space, but shape it according to their ideas, which are determined, for example, by tradition, politics, economic conditions and fashion trends."

1.1.3 Urban Ecology

This term is not "to be equated with the term" urban ecology "." (Sukopp et al 1998: 4) In contrast to its German counterpart, Urban Ecology does not have its roots in geo-ecology, but in sociology. From this it can be concluded that this term describes the relationships between people and cities more than urban ecology does.

2 The Chicago School

2.1 definition

According to Werlen (1990: 243f), the "Chicago School of Sociology" was influenced by two important theories: on the one hand, it was based on the plant ecology of Johannes Eugenius Warming, who found that plants tend to form groups or communities. "Plant communities", says Park (1974, cited in Werlen 2000: 243), "have a considerable number of properties of living organisms: They arise gradually, and are then replaced by other communities of very different kinds."

This socio-ecological theory school resulted in a large number of studies which, among other things, resulted in three models, theories and approaches for urban development. According to Albers (1974: 4, quoted in Heineberg 2000: 101), it was “attempts to theoretically penetrate urban growth and structure”. It was therefore essential to research certain regularities within the city that affected the social and economic life. According to Friedrichs (1989: 29) the most important foundations of the research direction, which has not lost its importance to this day, were the following:

1. The University of Chicago was the first to have a sociology chair as early as 1892.
2. The city of Chicago was characterized by very high population growth. This increase was due in particular to immigration and immigration. There was also a large number of ethnic groups and, in addition to considerable social problems between them, economic conflicts had to be resolved.
3. As early as 1920, census data existed for 70 districts in Chicago.

2.2 Biography: Robert Ezra Park

In order to get a better idea of ​​the theory of the Chicago School, it is essential to give a more detailed description of its founder, Robert Ezra Park. Park's attitude to his work can be understood with the following quote: "Why go to North Pole or climb Everest for adventure when we have Chicago?" (Park, quoted in Lindner 1990: 50)

Park was born in Harveyville, Pennsylvania in 1864 and grew up on the banks of the Mississippi. After leaving school, he studied engineering at the University of Michigan and, from 1883 to 1887, philology, history and philosophy. This first university section was followed by extensive work as an editor. During this time, he formed a first impression of the sociology of the Cities: He found work in Minneapolis, Detroit, Denver, New York and Chicago, among others.

He later resumed his studies and, in addition to Harvard, attended universities in Berlin, Strasbourg and Heidelberg, where he received his PhD in 1903 for a thesis on "crowd and audience" (Lindner, 1990: 52) In the USA he worked for a short time as a philosophy professor at Harvard and then as a press agent for a colored civil rights activist, a work that Park pursued for 12 years.

Finally, in 1914, Park came to the University of Chicago as the first American professor of sociology (Werlen 2000: 243). The Chicago School of Sociology could begin. Park's essay "The City" heralded the age of urban structural models. He left the university in 1938, which neared the end of the Chicago school. Robert Ezra Park died on February 7, 1944.

2.3 The three urban structure models

2.3.1 The Burgess circular model

Park employee Burgess developed the Chicago School's first urban structure model in 1925. His model is called a ring model, but also a zone model or a circle model. It counts as a classic of urban ecological theories and served as a template for other models.

Burgess assumes that cities can be divided into several zones, but these are not timeless. The urban movement is mobile due to constantly moving groups, land use changes and expansion. In the case of Chicago, he divided his model into five zones, which "zona-peripherally" (Hofmeister 1997: 156) extend circularly from the CBD with a constant radius.

All of these following zones combine several factors that continuously decrease from the loop to zone V (density, crime, low status, etc.).

Figure not included in this excerpt

Fig. 1: The Burgess zone model.

The CBD as Zone I is surrounded by 4 additional zones (source: Breßler 2001).

Tab. 1: The five zones with their typical features.

Figure not included in this excerpt

According to Friedrichs (1980: 101) his theory is based on two basic hypotheses:

- ,, When a city expands, it does so from the inside out. The expansion tends to be uniform in all directions. "
- ,, When a city expands, the uses and population groups of a zone penetrate into the next adjacent outer zone. Uses that are represented in the city are expanding the most. "

Park calls this phenomenon the "theory of concentric growth". This means that the model must not be viewed as rigid, but as a mobile, expanding model. Each zone expands into the next, if viewed over a longer period During this period, Zone II gives way to the CBD, which in turn extends to the workers' residential area, following the principle of succession.

This high mobility promotes segregation. Since immigrants in particular are staying in the zone in transition, the ethnic minorities gradually clump together. In the case of Chicago, this led to the formation of a black belt, a "Chinatown", to "Little Sicily", the residential area for Italian immigrants and other areas in which there were clusters of origins.

2.3.2 The sector model according to Hoyt

Between 1900 and 1936, Hoyt examined the residential areas of high-status strata in 30 North American cities (Friedrichs 1983: 106). Based on his observations, he came to the following conclusion in 1939:

- Areas with high status strata extend along the traffic axes.

- Areas of high status attract the growth of the city in their direction.

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Fig. 2: The sector model according to Hoyt (source: Breßler 2001).

In contrast to Burgess, Hoyt recognized the tendency of the layers mentioned (up to Zone IV) to keep the temporal distance relatively small in order not to drift into the periphery. "Hoyt assumed that residential areas, especially those of the upper classes, develop sectorally and that these sectors expand with urban growth and expand outwards, and that this sectoral development is underlined by the (radial) traffic lines" (Hofmeister 1997 : 157).

Due to the development of increasingly important traffic axes, more modern factors are implied in this model. But this model is only a theory, not a concept of a city.

2.3.3 The multicore model according to Harris and Ullman

The third classic city model is the so-called multicore model by C. D. Harris and E.L. Ullman. The term "multiple nuclei theory" is also often found in American literature. This model from 1945 was intended to replace the sector model, which was still regarded as unrealistic, and to represent a further step away from the general public. Harris and Ullman's hypothesis is that with increasing Size of a city, the number and also the specialization of its cores increases (Friedrichs 1983: 109).

This means that remote centers with different uses, such as smaller business or shopping parks, cultural centers, parks or industrial plants, are emerging. So you get a mosaic, as it is often made up of many different parts of the city in reality.

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Fig.3: The multi-core model according to Harris and Ullman (source: Breßler 2001).

The founders of this model do not neglect the question of the central function of a city for its surrounding area. According to their theory, it is possible to define three different types of cities, depending on the respective field of activity of the city (Friedrichs 1983: 109). On the one hand there are "central locations with a multitude of services". This type of city is found evenly scattered across the country and in Germany could be compared with Leipzig, Nuremberg or Hanover.

The second type are the "transport cities or cities of goods handling or loading" (Hamburg, Rostock or Bremen). "Specialized cities, e.g. mining, production or recreation cities" result in the third type of city. They are characterized by a certain resource dependency, such as coal or iron ore. Air and water quality and the proximity of the forest can be important determinants for the cities of recreation. As a result of this differentiation, according to Friedrichs (1983: 109) the following assumptions can be made:

1. "The original core of a city is formed by those uses that correspond to the type of city." Thus, the retail trade is a fixed main component of the so-called central places. This is why these cities are mainly characterized by concentrated shopping and service centers, such as elegant shopping arcades and cinemas , Bar streets and cafes.

In the transport cities, on the other hand, train stations or large port districts can often be outsourced. For the specialized cities, the original core of the city is formed by a concentration of large factory and raw material extraction systems, or for the resort city by attractive places for recreational activities.

2. "Unless several cores already exist in a city, these as well as districts of different uses arise in the course of the development of the city." This assumption becomes clear when one has the model of Harris and Ullman in mind.

Areas of different use are clearly visible there, e.g. low, middle and high status residential areas, light and heavy industrial zones, main and secondary business centers, and you can see the differences in expansion between the central city area (CBD) and remote usage units.

This suggests that it is "not about the localization of different social classes in the urban space, but about the spatial differentiation of the workplace sector".

3 criticism

3.1 Criticism of Burgess and Hoyt

3.1.1 The problem of delimitation

Most critics agree on this: The socio-ecological distribution of the population cannot be represented as simply as Burgess divided the sectors into categories. Alihan (1938: 224f., Quoted in Friedrichs 1983: 112) criticized the following: "Since gradients imply a continuum, one does not need to look for specific zones in the delimitation, but can create any zones." These gradients relate to factors such as density, crime, land price, population status, etc. Through this smooth transition, a new group with any number of sub-groups could be formed at any location.

How does Burgess organize the groups? How can he strictly separate them from the others? These questions occupied social ecologists like Hunter or Timms in the context of factor ecology.

Similar objections were raised with the sector model by Hoyt, but he emphasized that his classifications refer to the most extreme manifestations of the respective status groups and he left the respective researcher to find suitable indicators (Friedrichs 1983: 112).

3.1.2 Validity of the models

The models can only be applied to cities in rich, industrialized and capitalist systems. A free or socially functioning market economy is a prerequisite for the application of the theories. As already mentioned, the models are socio-ecological, not cultural-ecological or political. For example, if one looks at South American cities, one can observe an inverse behavior of some gradients, as for example with the factor of social status. Favelas or slums gather here on the outskirts of the city (Friedrichs 1983: 112).

Another major problem of the Chicago School "lies in the confusion of abstraction and reality" (Saunders 1987: 72). Therefore, the symbolic value that real estate can attain was not taken into account. Cemeteries were and are not relocated, although they are fatal obstacles to traffic According to Saunders (1987, p.72) it can be concluded that "cultural values ​​and intersubjective meanings are very decisive variables in explaining patterns of land use [...]".

3.1.3 The vertical factor

All three models can be assumed to ignore the vertical factor. None of the theories mentions that high strata tend to settle on slopes and hills. The zonal and sectoral spatial arrangements change fundamentally due to geomorphological conditions.

3.2 Criticism of Harris and Ullman

The theory of Harris and Ullman was criticized in the direction that their model does not reflect the development of a city, but rather models the structural city structure. According to Friedrichs (1983: 110), this is a model in which "the central local theory of space is transferred to the internal structure of a large city."

Another reason for discussion is the not necessarily exact separation between core and district. The model often speaks of the areas (districts) with different uses, but what about the cores remains unanswered.

Because the founders of this model do not give an exact explanation for "core", but rather see the term with a broader meaning, since they "also speak of cultural centers, parks, small industrial centers as" smaller cores "" (Friedrichs, 1983: 109).

4 Summary

As the founder, Robert Park was instrumental in the development of the Chicago School. Due to its rich journalistic activity, it was also often referred to as camouflaged journalism. The Burgess and Hoyt models are often misunderstood as urban development guidelines. However, they are a purely theoretical construct which in the zone model only refers to Chicago. Harris and Ullman's model can be described as a snapshot of a city.

However, the Chicago school shows interesting sociological connections (segregation, succession), which can serve as knowledge for the improvement of social connections in a city. The conception of this theory school must take place from a sociological, not from an anthropogeographical point of view.

5 literature

Carter, H. & F. Vetter (Eds.) (1980): Introduction to Urban Geography. Berlin / Stuttgart.

Friedrichs, J. (19833 ): City analysis. Social and spatial organization of society. Opladen.

Hamm, B. & I. Neumann (1996): Settlement, Environment and Planning Sociology. Ecological Sociology Volume 2. Opladen.

Heineberg, H. (2000): Grundriß Allgemeine Geographie: Stadtgeographie. Paderborn. Hofmeister, B. (19977 ): Urban geography. Braunschweig.

Lichtenberger, E. (19912 ): Urban geography. Terms, concepts, models, processes. Volume 1. Stuttgart.

Lindner, R. (1990): The discovery of urban culture. Sociology from experience. Frankfurt / Main.

Saunders, P. (1987): Sociology of the City. Frankfurt / Main / New York.

Schwarz, G. (19894 ): General settlement geography. Part 2: The cities. Berlin.

Sukopp, & H. R. Wittig (Eds.) (19982 ): Urban Ecology. A textbook for study and practice. Stuttgart.

Werlen, B. (2000): Social geography. Bern.

Literature from the Internet

Breßler, C. (2001): www.userpage.fu-berlin.de/~bressler/geoskript/siedl3.htm accessed on 02.02.2002.