Sector Theory
In 1939, Homer Hoyt propounded an alternative theory of urban structure and its growth pattern. Through the sectors model, Hoyt tried to overcome the weaknesses of earlier theory of Burgess. Hoyt argued that cities do not develop in the form of simple rings, instead, they have ‘sectors’.
Sector Theory of urban structure and its growth was mainly based on residential rent patterns and the impacts of transportation development. In an empirical study of American cities, Homer Hoyt observed that high-rent areas are located in one or more sectors of the city. He prepared a map showing how rent changed by sectors irrespective of concentric circles. Generating from the maps of housing features and land use patterns of cities, he analysed the impact of transportation on the recreational areas and other changes.
Homer Hoyt suggested that few activities grow in the form of sectors that radiates out along the main travel links. Activities in a sector are considered to be the same throughout the sector because of the purpose/function it serves. These sectors grow along railway lines, highways or rivers.
According to this theoretical model there are five major concentric zones. These are as following:
- Central Business District (CBD)
The inner most ring zone or nucleus of the city is a commercial centre also called Central Business District (CBD). This zone is characterized by high intensity of commercial and civic amenities. It is the heart of the city which includes department stores, office buildings, shops, banks, clubs, hotels, theatres and many other civic buildings. Being the centre of commercial activities and location, it is accessible from all directions and attracts a large number of people. Therefore, it is a zone with the highest intensity of land use and social interaction. The high intensity of land use further indicates the high value of land and rents.
As a result, the residential population in this zone is very small. People in search of cheaper, spacious and pollution-free accommodation move away from the core of the city. This is one of the reasons that the congested city area is deserted at weekends or on non-working days.
Burgess further describes that the morphological structure of CBD is changing rapidly with our changing needs. The rearrangements occur through new building construction. This is a continuous process of rebuilding since the city began.
- Zone of Transition
The zone surrounds the CBD area and fulfils its needs, like light industrial production and business extension houses. Light Industries and slums mainly occupy this zone, which may be seen in many cities. It has low-income households. This zone was the home of numerous first-generation immigrants. It is a breeding place of crime, gambling, sexual vice and other social deviances.
The physical deterioration, poor housing and social disorganization lead to the concentration of poverty, juvenile delinquency, family disintegration and diseases. The second concentric zone tends to be transitory in nature, comprising an area of residential deterioration due to congestion and encroachment.
- Lower Working-Class Residence
Basically, it is a planned residential area, close to places of economic activity which often shift and moved to the outward rings. Being close to the transition zone is influenced by that zone, in terms of quality of life. It reflects the negative impact of industrial pollution and the cultural impact of slums. The subsequent outward rings of working-class residences are occupied by middle or higher-class residences.
- Middle-Class Residence
These may be separated into different rings in terms of class character and corresponding facilities. This is a residential area with all the modern amenities of civic society. The houses are spacious in a pollution-free zone. Sanitation, health facilities and all other requirements of a good quality of life are found here. Proper transportation, communication and parking facilities are added features of this residential zone. The above features of this concentric zone clearly indicate a particular class character.
- Commuter Zone
It is located in the outermost concentric zone, beyond the area of higher-class residence. This is a ring of encircling small cities, towns, and hamlets which taken together constitute the commuter zone. People from these areas commute on a daily basis towards the CBD or commercial centre for employment and business purposes but live in their small cities, towns and hamlets. Commuter zone is characterized by low density. It is relatively isolated and located in suburbs and satellite towns.
Limitations and Criticisms of the Concentric zone model
The concentric zone model is one of the simplest models available. This model accounts for the economic forces which drive development and the study of patterns present at the time of the study. But with the evolution and passage of time urban areas grew more complex and this model cannot define the development of existing cities. Some of the limitations and criticism include
- Although widely appreciated in the United States, Burgess’s model is not applicable outside the US. This is so, because the pattern of growth is different because of various circumstances.
- The relevance of this model decreased over time. With the advancement in the mode of transportation, mass transit vehicles and motor vehicles changed the way people commute. Accordingly, their preference for living in a particular zone changed.
- It does not take into account the effect of political forces and the restrictions imposed by the government for the improvement of living conditions.
- In reality, no distinct zones and boundaries exist as overlapping of areas is possible in every town. The preference of people changes over time depending on the importance they associate for a particular benefit.
- This model is not applicable to polycentric cities as many CDB exists in such towns. Moreover, every city is different, and the factors influencing the growth of a city are diverse.
Components of Hoyt Model
1. CBD – Central Business District
It is placed at the centre. In this area sectors and the partial rings of land use/activities take place. This area is often known as downtown and has high-rise buildings. The inner-city area or downtown represents many layers of the historic growth of many generations. It also reflects the impact of the culture and traditions of the people who inhabited the city. As the cities expands and modern technology and scientific innovations transformed the style of living and also the structure of the city, open spaces were being eaten up by built forms resulting in a congested and unhealthy environment.
2. Industry
Industries are represented in the form of a sector radiating out from the centre. These forms sector because of the presence of a transport linkage along which the activities grew. The presence of railway line, rivers or roads would attract similar activity and thus a continuous corridor or ‘sector’ will develop.
3. Low-Class Residential Area
Low-income groups reside in this area. Narrow roads, high population density and small houses with poor ventilation exist in this area. Roads are narrow and often connect to the industries where most of the people in this sector work. Closeness to industries reduces the travel cost and thus attracts industrial workers. Environmental and living conditions are often inadequate because of the proximity to factories.
4. Middle-Class Residential Area
This area has middle-income groups who can afford more substantial travel costs and want better living conditions. The activities of people residing in this area consist of different activities and not just industrial work. It has more linkages with CBD along with some linkages to industries. This area has the most significant residential area.
5. High-Class Residential Area
This is the outermost and farthest area from the downtown (CBD). Wealthy and affluent people live in this area. This area is clean, has less traffic. It is quiet and has large houses. The corridor or spine extending from CBD to the edge has the best housing.
Features of sector model
· The presence of low-income groups near industries supports Hoyt Model
· The Hoyt model realized that transportation (in particular) and access to resources caused a disruption of the Burgess model.
· Transport linkages profoundly influence activities and their locations. Low transportation cost and proximity to roads/railway reduce the cost of production.
· Account for major transportation routes and its effect on activities
The significance of Hoyt Model
· Ecological factors and the economic rent concept to explain the land use pattern
· Stress on the role of transport routes in affecting the spatial arrangement of the city
· Both the distance and direction of growth from the city centre are considered
· Brings location of industrial and values of environmental amenity as determinants in a residential place
Example: Sectors of high-class residential areas tend to grow towards higher grounds, sites with a better view, more open space, the homes of influential leaders within the community and existing outlying, smaller settlements. Within the residential sector, it has been observed through study that the inner portions are found to be having older houses and newer constructions are found on the outer fringes.
Limitations of Sector Model
· Only Railway lines are considered for the growth of sectors and do not make allowances for private vehicles.
· It is a monocentric representation of cities; multiple business centres are not accounted for in this model.
· Physical features may restrict or direct growth along specific wedges
· No reference to out-of-town development
Comparison with Concentric Zone Theory
Both sectors model and concentric zone, have the common concept of CBD i.e., the Central Business District and outward expansion. Where the former differs in terms of differential radial growth from CBD or centre. The sector theory explained that sectors develop because of the difference in accessibility from outlying portions to the core region. Thus, it also includes the development of concentric patterns within the zone.
Contrary to Burgess’ Concentric Zone theory, the sectors theory assumes that land rents change from Sector to Sector, not in the form of the successive concentric ring area. The development of a sector is determined by various factors, such as planning, transportation, the class character of residents and other facilities available to that particular sector.