Urban Landscape
Contents • • Urbanization Network of Urban Centres Spatial Patterns in Urban Landscapes Urban Problems
Urbanization • • Meaning of Urban Settlement Urbanization and Urban Growth Causes of Urbanization Difference between developing and developed countries
Meaning of Urban Settlement • Four general approaches for classifying urban and rural – Administrative divisions • Type of local government – Administration centres of all minor divisions – Population clusters – The presence of non-agricultural activities
Population clusters • The minimum size adopted by various governments, however, varies greatly. Country Sweden Papua New Guinea Canada United States India Switzerland Minimum Population of Settlement Considered to be “Urban” 200 500 1000 2500 5000 10000
Non-agricultural activities • Urbanization is based on the assumption that a town may be more suitably differentiated from rural centres by the presence of non-agricultural activities, and the official definition of urban status in countries such as Israel and Yugoslavia included such criterion.
Urbanization and Urban Growth • It is clear that urbanization and the growth of cities have become one of the major characteristics of the present century. • Northam: "Urbanization is the process whereby a society is transformed from an essentially rural to a predominantly urban one. It has a beginning and an end. In contrast the growth of cities has no limit. "
Urbanization – meaning 1 • Measure of the degree of urbanism (level of urbanization) in a society • The proportion of the total population in country living in urban settlements. Country Number of urban centers Average size of urban centers Total urban dwellers A 10 500000 4000000 12. 5 B 5 40000 200000 1000000 20 Urban Size and Urbanization Total Level of national urbanizati population on (%)
Urbanization – meaning 2 • The process by which this proportion of urban dwellers increases over time. • Different between urbanization and urban growth Year Total national population Total urban dwellers Level of urbanization (%) Urban Growth 1800 1850 1900 1950 2000000 4000000 8000000 14000000 600000 1200000 4800000 8400000 30 30 60 60 ----600000 3600000 Urbanization and Urban Growth
Causes of urbanization • An Efficient Agricultural System – makes surplus quantity of food possible to sustain the urban population • Invention of power-driven machinery – The industrial revolution Factories development – concentration of production into bigger factories requiring large number of workers • The development of Trade and Services – employment in the service, or tertiary sector of the labour force has been an important factor in the growth of cities
Causes of urbanization • Development of Transportation – – It allows goods to be transported freely It possible for people to move freely Intra-urban transportation Enable mass movement of people between home and work places – Widespread use of automobile and truck – Decentralization of people and functions within urban areas • Demographic and Social Factors – Natural Increase (Cities) – about 20% • Reasons: improvement of sanitation, health care, social welfare, ……
Rural-urban Migration • Push-Pull Model Barriers Origin Positive Factor (Pull factor) Negative Factor (Push factor) Destination > < Move Stay
Urbanization in developed and developing countries • Developed countries – attenuated ‘S’, Curve • Developing countries – ‘J’ curve or rising line
Causes of urbanization – Developed Countries • Industrial Revolution (End of 19 century) • Western Europe and North America • Causes – – – Farming mechanization Increase agricultural efficiency Release labour forces from rural Fast development of industries in cities Provide many jobs • Slow increasing rate in Urbanization • Eg. England Wales 10% in 1891 but 60% in 1973
Causes of urbanization – Developed Countries Origin: Rural Area Destination: Urban Area Push factors Pull Factors Ø Unemployment for mechanization Ø Many job opportunities for industrialization Ø Low standard of living Ø Higher standard of living Ø Low wages Ø More education Ø Poor education Ø Higher wages Ø Poor view of future Ø Better health care Ø Better view of future
Causes of urbanization – Developed Countries 2 (Suburbanization)rate in suburban zone is • Population growth higher than that in inner zones of the city. • City scale not national scale • Causes – Satellite and new town formation – Improvement of living standard – Improvement of transport between CBD and suburban – Government policy, eg. Urban renewal programme Slum clearance…. .
Causes of urbanization – Developed Countries 2 (Suburbanization) Origin: Urban Area Destination: Rural Area/ New Town Push factors Pull Factors Ø Overcrowded living environment Ø More open space, more pleasant living environment. Ø Pollution Ø Fresh air, quiet Ø Traffic congestion Ø Lower land rent Ø High crime rate Ø Lower crime rate Ø Higher land rent. Ø Large modern shopping centres in suburb. Ø Large modern factories, more job opportunities
Causes of urbanization – Developing Countries • Post World War II (1945) • Countries in Africa, Asia and South America • Rapid rate of urbanization – 1920 -1970, people living in cities of 100000 or more increased 275% in the developed countries but it was 675% in developing countries. • Causes – High natural increase (high birth but low death rate) • Great contrast in social, economic and medical in cities than in countryside. – Rural-urban migration • Rural Economics Collapse
Causes of urbanization – Developing Countries • Rural Economic Collapse • Push factors are more important than pull factors • Hope for improvement is a key force (dream) Push Pull
Rural-urban migration – developing countries
Rural-urban migration – developing countries • Urbanization is ahead industrialization – Urban lack the economic capacity to support such urbanization – Industrial growth is sluggish – Unemployment in urban – It cannot absorb the tremendous influx of rural migrants • Improvement of transportation – People can migrate more easily – Diffusion of information from the urban
Rural-urban migration – developing countries • Worse rural conditions – High rural density – Great strain on the agricultural resources – Overcrowding, overgrazing, soil erosion, – Declining productivity – Unemployment – Droughts or famine • Political instability
Problems from rural-urban migration – developing countries • Dream – Hope of finding jobs – Better standard of living, better views of future • Urban cannot cope with such excessive labour – Unemployment, high crime rate • Housing problems – Shanty towns, squatters and slums – Extremely miserable living environment • Urbanization in developing countries is problems creator.
Networks of Urban Centres – Central Place Theory • • • Central Places Assumptions Building of theory Evaluations of the central place theory Application of the central place theory Conclusion
Central Places • Urban settlements are seemed to be unorderly pattern and no definite factors controlling location, size and spacing of settlement. • Good location: availability of water, height of the land, plain, fertile soil, …. . (old approach) • Urban settlemnts are affected by it accessibility to people. (location on routes, road, rail, water routes……) It is good for importing raw materials and exporting finished products. • The size of settlement is determine by its location
Central Place • In 1933, Walter Christaller finished the book ‘Central Places in Southern Germany’ • Every town acts as a focus for the surrounding countryside. • Every town as a central place. • Central places are settlements which are centrally placed within the area which they serve. • A central place serves and provides its immediate region with goods and services. • Some central places are more important than others. They have more services and serve a larger area.
Assumptions • An isotropic plain • Transport costs are proportional to distance, single uniform transport system and an uniform transportation network in all directions (equally accessible) • The population is even spatial distribution. • Common culture and a common level of technology • The income, demand schedules, and propensities to consume are all equal. • Producers and consumers behave in an optimum fashion. • Desire of people: Incomes of the people offering goods and services should be maximized and the
Building of theory • • • Threshold Value Range of goods/ services The shape of the Tributary area Different orders of goods A hierarchical spatial arrangement of central places • K value (3, 4, and 7)
Real pattern of urban settlement
Threshold Value • Minimum population that is required to bring (support) about the offering of a certain type of goods for sale to sustain any service. • Minimum level of demand as the threshold value. • The minimum population require to bring about this demand is known as threshold population.
Range of Goods/ Services • Maximum distance over which people will travel to purchase a piece of goods or a services offered at a central place. (Max. serving area of a central place. )
Demand curve and Demand cone • The quantity of the goods that a consumer will prepare to buy depends on the actual price of the goods. • The price to the customer varies only with his distance. • The further he is from the central place, the less he will consume.
Upper limit and lower limit • The upper limit is the range of a type of goods from a central place. • The lower limit is the threshold value. • It is impossible for the whole population to be served from only one central place. • Various central places will appear each having its own circular market area. Lower limit or threshold value Upper limit or Range of goods
The shape of the Tributary Area
Different orders of goods High order goods Medium order goods Low order goods Values High Medium Low Frequency Low Medium High Threshold Population Large Medium Small Range of goods Large Medium Small No. of Activities Small Medium Large
Different orders of goods • It is impossible for all kinds of goods and services to be provided at all locations. • The distribution of the central places will be shown in the figure which shows that the different orders of goods are arranged in an orderly hierarchy.
A Hierarchical spatial arrangement of central places
K value (3, 4 and 7) • There are 3 possible spatial arrangement of central places (K value) • K=3 (Marketing Principle) • K=4 (Transport Principle) • K=7 (Administration Principle)
Marketing Principle (K=3) • The boundary of a central place’s market area passes through six other consumption centres. • The demand of each of these centres is shared with
Marketing Principle (K=3) • Number of Central Places: – The number of lower order central places is 3 times the number of its next higher order one. – From the highest order central place to the lowest order central places, the ratio is 1: 2: 6: 18: 54…… • Serving area of a central place: – The serving area of a central place is 3 times the area of its lower order one. – From the lowest order central place to the highest order one, the ratio is 1: 3: 9: 27: 81: 243……. . • Spacing (Distance) of central places: – The spacing (distance) of the same order central place is calculated by (where n is the order of central place)
Transport Principle (K=4) These central places lie on main transport routes connecting the higher order centres. • The boundary of a central place’s market (serving area) passes through six other centres • The demand of each of these centres is shared with other central places (1/2, K=4)
Transport Principle (K=4) • Number of Central Places: – The number of lower order central places is 4 times the number of its next higher order one. – From the highest order central place to the lowest order central places, the ratio is 1: 3: 12: 48: 192…… • Serving area of a central place: – The serving area of a central place is 4 times the area of its lower order one. – From the lowest order central place to the highest order one, the ratio is 1: 4: 16: 64: 256……. • Spacing (Distance) of central places: – The spacing (distance) of the same order central place is calculated by (where n is the order of central place)
Administration Principle (K=7) Efficient administration is the control the whole area and it is impossible shared with other centres. • All 6 tributary centres are under the control of the central place.
Administration Principle (K=7)
Administration Principle (K=7) • Number of Central Places: – The number of lower order central places is 7 times the number of its next higher order one. – From the highest order central place to the lowest order central places, the ratio is 1: 6: 42: 294: 2058…… • Serving area of a central place: – The serving area of a central place is 7 times the area of its lower order one. – From the lowest order central place to the highest order one, the ratio is 1: 7: 49: 343: 2401……. • Spacing (Distance) of central places: – The spacing (distance) of the same order central place is calculated by (where n is the order of central place)
Combination – No Pattern
Evaluation of the central place theory • • Criticisms Values of the Christaller theory Application of theory Conclusion – Hierarchy of settlement – Centrality score
Criticisms • Christaller has not given a satisfactory explanation of the hexagonal shape of the complementary areas. • Regular arrangements of the central places have only been tentatively demonstrated. • A hierarchical structuring base on the assumptions of an isotropic surface, but the aggregation of areas masks this structuring. • It is economic deterministic. It allows no account of individual perception. • Restricts of tertiary production. • Distribution of towns in most area of the world reveals no sign of a hexagonal shape.
Criticisms - 2 • Towns do not fall into discrete classes but rather are spread uniformly along a continuum of sizes from the smallest to the largest. • It applies well in poor and thinly settled farm districts with simple social organization and mainly selfcontained, but not works well in manufacturing area. • Highest-order center offers all the low-order services – Some low-order service may not be offered in highestorder center • The centers of the same order will offer same range of services – The services offered by the centers of the same order may
Values of theory • It shows the interdependence of town and its hinterland. • A hierarchy of functions and of settlement is devised. • The idea of competition between centres is stressed in the marketing principle. • It is possible to make a number of predictions about the pattern of future settlement location. • It defines the ideal pattern of central places and explains why an urban hierarchy may exist in the reality. – A small number of high-order centers serve large hinterland; – Many low-order centers serve small hinterland. • It provides a basis for planning the size and spacing of
Application of the central place theory in China Skinner’s study • • There are 3 levels of towns – Standard market towns – Intermediate market towns – Central market towns • • • Urban system in Guangdong (1998) Urban system in Zhejiang Urban system in Hong Kong Shopping Centres planning in Hong Kong The impact of increased population density or increased income of population • The impact of improved transportation on central
Standard market towns • It provided for the exchange of goods produced within the market’s dependent area. • It was the starting point for the upward flow of agricultural products and the termination of the downward flow of imported items in the marketing system. • Most of the standard
Intermediate market towns • Markedly larger than standard market towns. • Intermediate positions in the vertical flow of goods both ways. • Farmers seldom direct go to these towns unless they happen to live within immediate vicinity of the intermediate market
Central market towns • Highest in the hierarchy. • Normally situated at a strategic site in the transportation network. • The functions not only as wholesaling centres for the rural markets but also offer upper-level goods and services
Urban system in Guangdong (54 cities by total population in 1998)
Urban system in Zhejiang
Urban system in Hong Kong
• Shopping centre planning in HK Metropolitan Centers – Catchment population: Whole HK and tourists – Range of goods: consumer durable goods, many banks and commercial services, cinemas, theatres, restaurants, entertainment and social facilities. – Examples: located at Central, Tsim Sha Tsui and Causeway Bay
Shopping center planning in HK • Regional Centers – Catchment population: 250, 000 to 1, 000 – Range of goods: department stores/supermarkets, many ancillary services, i. e. banks, restaurants, cinemas, theatres and other social facilities – Examples: new town centers. Typical centers may range from 50, 000 to 250, 000 sq. m.
• Shopping center planning in HK District Centers – Catchment population: 50, 000 to 250, 000 – Range of goods: limited entertainment and social facilities, but significant concentrations of retail facilities and restaurants – Examples: mediumscale shopping centers of town-wide or district significance, Wan Chai in the urban area and Kam Tin in NT. Typical centers may range from
Shopping center planning in HK • Local Centers – Catchment population: less than 50, 000 – Range of goods: small-scale concentrations of shops for local retail services and restaurants, such as in Fung Tak Estate and Tai Yuen Estate. Local centers are less than 10, 000 sq. m. • Source: HK Planning Standards and Guidelines, http: //www. info. gov. hk/planning/tech_doc/ hkpsg/index_e. htm
The impact of increased population density or income of population • Consumer expenditure will increase • Further high-order services will be required • Increase the potential number of levels of hierarchy • Increase the degree of functional specialization of the highest-order center
The impact of improved transportation on central place system • Population mobility increased • People are willing to travel longer to obtain services • Market area of a central place will expand • Restructuring of central places, some have to be closed.
Conclusion • Christaller has presented urban hierarchies of both vertical and horizontal, cities of the same order were equidistant apart. • As for vertical hierarchy, smaller central places will be nested within larger central places according to marking, transportation and administrative principles. • It is applicable to retailing. • Smaller shopping centres will sell less goods with a smaller range of goods and threshold value but much more frequently visited by customers. • Such settlement patterns are more likely to be found in non-industrial or rural areas.
Hierarchy of settlement • It can be explained in two ways: • Size of population and Number of functions • Size of population – The larger settlement serve large area and small settlement serve small areas • Hamlet, village, town, city, conurbation, metropolis, metropolitan – Hierarchy of shopping centres within a single urban area. • Local centre, district centre, regional centre, metropolis centre.
Hierarchy of settlement - 2 • Number of functions – The larger settlements are having greater number of functions while the smaller settlements are within smaller number of functions provided for local people. – If there are two towns of different sizes but equal in importance as central places, the smaller town may be regarded as having a higher central place status • Resort town has a higher status than residential town. – Improvement in transport • There are fewer smaller settlement especially
Centrality score / index • The greater the index, the higher the status as central place. Usually the higher the rank of central place, the more population. • Centrality score / index Where C = Coefficient of location of the function t = Number of outlets of function ‘t’ in one town T=Total number of outlets of function ‘t’ in the whole system
Centrality score - 2 Furniture Clothing Grocers Jewellery Doncast er Sheffield 49 247 196 48 183 764 1067 199 Barnsley 26 148 199 31 Rotherha 30 115 154 m • Index of centrality 1274 of Doncaster Total 288 1616 32 310
Spatial Patterns in Urban Landscapes • Distribution of Urban Population / population density – The pattern – Difference between developed and developing countries • Economic Factors affecting distribution of urban population – Urban land rent – Bid rent curves – conclusion
Spatial Patterns in Urban Landscapes - 2 • Urban Land use – CBD – Commercial landuses – Zone in transition – Residential – Manufacturing • Urban Landuses Model – Concentric Model – Sector Model – Multi-Nuclei Model
Distribution of Urban Population sparsely populated • The city centre is very • Population density increases with increasing distance from the city centre.
Reasons • The city centre is very sparsely populated – The city centre is the most accessible place int eh city. – Land rent is very high. (competed by all landuse) – Onlycommerce enterprises can affored the high land rent. • Residential district immediately outside the city centre will be very density populated. – The low income group cannot afford the high transportation cost – They had to live in very small apartments or resort to subletting. • Population density is low in suburbs. – The rich live here. – Poor environment of inner city (high crime rate, pollution…) – They can live in spacious residences spread widely apart for low land rent. – They can drive to work everyday. • Density is extremely low towards the periphery. – Too far away and transport cost is too high.
Difference between developed and developing countries • Western Cities
Difference between developed and developing countries • Non-western cities
Economic factors affecting distribution of urban population • Urban Land rent – Urban land rent chiefly determined by the location measured in terms of accessibility. • Retailer will bid for the most accessible point for his market. • Manufacturers want to be near to the terminals to cut down the transportation cost. • The land would go to the highest bidder. • The market value and the land rent of more accessible area will increase. – City core is a point of intersection of most (most accessible location), so is the peak of land value. – Land value will decrease from the core towards the periphery for declining accessibility.
Bid rent curves
Bid rent curves -2 • Retailing demands greatest accessibility to the whole city population in order to maximize profits. – Away from the city centre, market declines very rapidly and so is the willingness to pay high rent. – The curve is very steep. • Offices of insurance firms, doctor, dentist can still survive in less accessible regions. – The curve is less steep.
Bid rent curves - 3 • If the curves are superimpose d, where the slopes intersect the users further away from the core will be out-bid.
Bid rent curves - 4 • Twodimensional diagram, a series of concentric zone will be generated
Conclusion • In fact, it is directly related to the distribution of transport networks. • Larger city, several major peaks may be found all near to the points of inter-section of roads or nest to the terminal of MTR. • Central peaks of land value will occur near the centre with a general decrease in all directions. • Ridges are relatively high value which extend along the major radial routes. • Rent, transport cost and location are interdependent.
Conclusion - 2 • Relationship between transport system and land rent
Urban Land Use • • • CBD Commercial landuses Zone in transition Residential Manufacturing
Central Business District CBD • CBD is the focus of transport routes and the area of the greatest pedestrian, vehicular traffic and a high intensity of urban landuse. – General Functions of CBD – Characteristics of the CBD – Criteria to delimit the CBD
General Functions of the CBD • Public Administration: – Government offices and departments (prestige reason) • Head quarter of the large companies – Insurance, financial business, multi-national…. . – Accessible to their clients and other businessmen with whom they have frequent contact and appointments. • Retailing and services – Large department stores and small specialty shops which sell high price luxury goods. – Many cafes and restaurants to supply meals to the working populations in the CBD. • Light industries – Printing and tailoring which have to accessible to customers – Only require a small floor space and usually occupy the upper floors • Entertainment: – Theatres, cinemas, shops and expensive restaurants.
Characteristics of the CBD • Maximum accessibility – Focus of transport routes and the terminal of public transport system • The Highest land value – Result of landuses competition • The tallest buildings – If the CBD is expanding horizontally, its efficiency will be deduced. – The vertical growth of the CBD is the result of technological changed. • Reinforced cement, lifts, escalators, air-conditioning, artificial lighting and improvement of architecture technology…. . • High day time and low night time population density
Criteria to Delimit the CBD • Appraised or Assessed Land Value – subjective • High Rent – Confidential and also subjective • Ratable value – Subjective and rating is not only base on the land value, but also the conditions of the buildings. • Building Height – Many non-CBD buildings are also very tall especially in HK • Vehicular and pedestrian traffic count – Traffic may be just passing through since the CBD is usually the focus of regional road network
Land Use • Derived by Murphy and Vance in 1955 • 1. Define the CBD and non-CBD land uses – Non-CBD: residential, govt. and public buildings, churches, colleges and industrial establishments • 2. Measure floor space devoted the CBD and non-CBD uses. – All storeys should be considered • 3. Calculate the following indexes – HI, CBII and CBI
The indexes • Total Height Index (HI) – HI = Total floor space / Ground floor space • Central Business Height Index (CBHI) – CBHI = Total central business floor space / Ground floor space – >1, more than the ground floor is devoted to CBD uses • Central Business Intensity Index (CBII) – CBII = (Total central business floor space / Total floor space) x 100% – Percentage of all available floor space in C. B. uses – Limiting value (say 50%) can be used as a standard in delimitation. • Central Business Index (CBI) – CBI = CBHI of at least 1 and CBII of 50%
Demerits of the Methods • The central business uses are subjectively determined • The variation in block size is not taken into account. • No account is taken of the quality of use of an area; a smaller corner shop and a specialized and expensive central shop belong to the same class.
Delimiting the Hard Core of the CBD • Murphy and Vance was modified by D. H. Davis. • Cinemas, hotels, head-offices, newspaper establishment, governmental offices and retail shops offering low quality goods (subjectively defined) were regarded as non -C. B. hard core uses. • CBI were increased to CBHI larger than 4 and the CBII of 80% is delimiting the hard core area.
Internal Specialization within the CBD • Various economic and functional links bind together the landuses which characterize these specialized area. • Theatres and cinemas and other forms of entertainment profit from each other’s presence. • Proximity of various government and administrative offices in the same district adds to the efficiency of the functioning. • If the rent of a site is very high, only a few functions can afford to utilize the site.
Commercial Landuses • Type of shops • Hierarchy of Retailing Centres within the city • Spatial Arrangement of shopping centres • Factors affecting decisions to locate a store
Type of Shops • Convenience goods store: – Patronized frequently and regularly. – Low threshold population and small range of goods (trade area) – Eg. Bread store • Shopper’s goods store: – Patronized less regularly, at intervals of about weeks or less. – Larger threshold population and larger range of goods (trade area). They have to seek a more central location. – Eg. Boutique, shoe shops (Durable goods) • Specialist store: – Selling goods needed only occasionally.
Hierarchy of Retailing centres • Shopping centres – Number of shops in present: • Higher order business centres will have more shops. – Types of goods available for sale: • Higher order centres will provide convenience goods and a wide range of shoppers’ goods while in low order centres, there may be an absence of shoppers’ goods • Four types of shopping centres: – The CBD (Metropolis centre) – Regional business centres – District centres – Local centres
Spatial arrangement of shopping centres • CBD providing both convenience goods for local needs and shoppers’ goods serve a much larger trade area. • Higher order centres require a large threshold population, and fewer in number, spread more widely apart to reduce competition. • The trade area of the low order centres will be nested within the trade areas of the high order centres. • The pattern is unlikely to be closely followed as accessibility (Christaller’s model) • Variations in density of population, income level of the people and the consumers’ behaviour are also
Spatial arrangement of shopping centres
Factors affecting decision to locate a store • Trading area potential: – pass the minimum threshold value • Accessibility to trading area – Competition for a site near to road intersection or corner sites at the main roads • Growth potential – Area with growing population or rising income • Business intersection – The pedestrian may be intersected along the main lines of daily movement.
Factors affecting decision to locate a • store attraction Cumulative – More similar stores concentrate in a small specialized area can attract more potential customers • Compatibility – Providing goods of compatible uses will generate maximum customer. • Minimization of competition • Rental value – Jewellery shop can stand high rental for because only a small space is needed. – Furniture retailing are space consuming and they cannot afford central locations
Zone in Transition • It is an area of mixed commercial and non-commercial landuse. • It separates the CBD with the surrounding residential neighbours or heavy industrial district, usually present are warehouse, light manufacturing, wholesaling, multi-family residents. • It is a former CBD. • Lack of renewal of old building will create deterioration and blight.
Residential areas • Distribution of houses within the city on two criteria: – House types – Socio-economic status of residents • Distribution of residential areas is the result of the distribution of socioeconomic groups
Social characteristic of residential areas • Population are segregated into social classes. • Social distance can be translated into physical distance, segregation groups can be occupied by separated residential area.
Intra-urban residential pattern • Kain – Wealthier classes move to the suburbs – Vacant buildings abandoned, old and declaim houses, are either redeveloped or deteriorated into slums. – The poor city workers, new immigrants and young students want to live near the city centre in spite of high density for they cannot afford the transport cost. • Shevky and Bell – The social changes will make the city population more heterogeneous. – People of different social ranks, family status and ethnic status will be segregated physically and live in different social areas.
Three locational pattern • Sector residential zone: – Zone are segregated according to their economic status or social rank. – The rich will move to the respectable district or districts with superior residential quality. – The poor is conformed to another sector zone adjacent to the industrial district. • Concentric zone: – According the life style. – Family oriented household will prefer the suburban houses – Non-family orientated households will prefer a small apartment near to the city centre. – People at different stages of their life circle will then have different housing need. – Districts will be occupied by people more or less in the same aged group or household of similar structure. • Clustered groups: – Similar racial, linguistic or cultural background will clustered together.
Ghettos • Immigrants from other countries, they live in slums created in the periphery of the business and industrial districts. (Transition Zone) • The new residents of the ghettoes may escape through the rising of economic and education status. • The Negroes found it impossible to leave the ghettos. Characteristics: – High unemployment, low income, less home own ship, substandard homing, inferior educational opportunities and inadequate
Manufacturing areas • Attraction of large cities for industry – Accessibility to Potential Customers • • Local market for the consumer goods A lot of industrial undertakings in the city Can save transportation cost by having a city location. Large cities are also ports (access to international and internal market) – Presence of External Economies • High concentration of industrial activities • Infrastructure (highways, railways, terminals, commercial facilities (advertising agencies, insurance company), educational institutes, research organizations…. . – Availability of Suitable Labour Supply • Large cities provide a pull of labour of varied skills. • Managerial staff, skilled, unskilled, low-paid (new immigrants and
Manufacturing area – 2 • Industrial structure of city • Factors influencing industrial location are mainly concerned with accessibility – access to water, power, raw materials, skilled workers, space, market, port facilities and so on…. – Characteristic Locations • Central location – highest accessibility • Along transport arteries or port industries – Good locations for assembling raw materials and distributing finished products – For access to unskilled and semi-skilled workers – Factories producing products for export. – Cannot afford the high land price of the central site • Scattered locations – Light industries • Suburban location – Large space needed, dangerous
Manufacturing areas - 3 - Trends • It shows the least tendency to agglomerate as compare to other landuses because each type of industry will have its own particular set of locational requirements. • Tend to be dispersed away from the city centre and have a linear appearance. – Reasons • Factories cannot afford the high rental in the city centre • Congestion in the city centre may lead to diseconomy • Large basic processing industries create a great deal of noise, smoke and unpleasant odour, will repeal other landuse development thus must be removed. • Large assembly plants may need an extensive area and location along the road and railways so that the transport of bulky materials and commodities can be facilitated. • Some large new plants like to seek a sub-urban location for
Models of internal urban landuses • Concentric Model (Burgess 1925) • Sector Model (Hoyt 1939) • Multi-nuclei Model (Harris and Ullman 1949)
Concentric Model • Study of Chicago by Burgess in 1925. • Urban landuse tended to display a zonal organization concentrically arrayed about the city centre. • Two assumptions: – Population is evenly distributed – Movement is equally easy in all directions – (isotropic plain)
Concentric Model - 2 • 1. CBD • 2. Zone in Transition • 3. Zone of Low-paid working class houses • 4. Residential Zone • 5. Commuter Zone
Concentric Model - 3
Concentric Model - 4 • Criticisms – Fails to consider the location of heavy industry. (transition zone was only about light industry) – Clear cut boundary – Too simple to summarize the model city structure. • It may be worked to the US cities of 1920’s. However, the internal structure of cities has become more complex now. – Star pattern is more common than concentric ring. – In reality, government planning is important in deciding landuse pattern – Paid little attention to the vertical variation in buildings height. – It is not universally available to all cities. It cannot be applied to pre-industrial city. – It is a static model
Concentric Model -5 • Star Pattern • Conclusion – It is too simple and too limited historically and culturally to a particular situation at a particular time in a particular country.
Sector Model • Study of residential rent patterns of 30 cities in the USA in 1939 by Hoyt. • Rent area in US cities tended to conform to pattern of sectors rather than concentric rings. • Similar type landuse tend to extend outwards from the CBD in elongated wedges along the radiating routes. • The model is widely applicable and an introduction marks a vital step from
Sector Model - 2
Sector Model - 3 • There is a difference in accessibility between the arteries (emphasis on the role of transport) • High rent residential districts grow in the direction of better environment (high ground open space, lake shore, sea coast, home of community leader, ……) • Low class residential districts develop in another direction properly adjacent to the industrial zone
Sector Model - 4 • Application: – Emphasis on the role of transport. – It recognizes the spatial association of mutually attractive landuse activities (light manufacturing zone and lowerclass residential zone) and mutually opposed land use activities (manufacturing zone and higher-class residential zone) – More reality is shown by considering the directional element of outward-oriented city growth. • Limitation: – Its narrow focus on housing and rent – Paid too little attention to the segregation of residence according to racial difference and religious creeds. – Paid little attention to the height of buildings and the variation of use with height.
Multi-Nuclei Model • It was developed in 1949 by Harris and Ullman reference with Detroit. (Auto centre) • A single CBD or a single shopping district is seldom enough to meet the need of a large number of business firms or upper class retail shoppers in a large city. • Landuse zones will develop around a number of separate nuclei like railways station and industrial complexes, in addition to the CBD. • Cities have a cellular structure. • Larger the city, the more numerous and specialized nuclei (landuse zone).
Multi-Nuclei Model - 2 ØIt is the most flexible and most applicable model of all theories. ØDispersal of urban functions were increased by car ownership. ØGrowth of retail sub-centres and the decentralization of population are the trend in the world cities.
Multi-Nuclei Model - 3 • Reasons for multi-nuclei: – Certain activities require specialized facilities. (CBD – max. accessibility; industry – along the water front. ) – Certain activities group together for bringing mutual benefits. (Retailing – increases the concentration of potentially customer; Industry – external economy) – Certain activities are detrimental to one another. (Industrial landuse and higher class housing) – Certain activities are unable to afford the high rent of the most desirable site. – Improvement in transport technology.
Multi-Nuclei Model - 4 • Application: – It is more complex and can be more appropriate in describing the land use in cities in reality. – It also allows for the characteristics of a city’s individual sites and the corporation of more general social and economic forces. – Include time dimension. It is a guide to think about the structure of the city rather than a generalization about urban forms. – It is the most flexible and widely applicable to large modern cities. – It reflects the tendency for dispersal of urban functions. (business, retailing, residence and manufacturing…. ) – It contains the concept of agglomeration, forces of attraction and repulsion. – Increase the sub-urbanization and decentralization tends to develop multiple nuclei. • Limitation:
Theories of Internal structure of city: Conclusion • Generally speaking, small towns (very old established towns) on flat land exhibit concentric zones, medium sized industrial towns have sectors, and large towns have multi-nuclei patterns. • Larger the town the greater will be the tendency to show aspects of all three models. • In the world’s largest cities, all three models pattern may be observed in superimposition. • Early growth may be around a central area and other nuclei, later growth would be conditioned by transport routes, finally adjustments of land use in response to land value changes would reflect a
Sydney
Southeast Asian Cities
Hong Kong (1970 s)
Hong Kong (1980 s)
Urban Problems • Transport Problems • Housing Problems
Transport Problem • Introduction: • The Problems • Solutions
Introduction • Transport is a service of all activities in a city. • City’s activities can be function in the best way with it. • Transport can also be regarded as a type of landuse. • CBD are the focal points of transport and the largest employment fields of the city, CBD are the areas of greatest traffic congestion. • Roads leading to factories, offices or schools will be congested with vehicles and people in the morning and in the evening.
Problems • Congestion – In most cities in the developed countries, rush hours (peak hours) may last for 2. 5 hours or 3 hours. – Congestion of urban central areas is due to the use of private cars, and the speed are greatly reduced (to 15 km/hr). – Many congestion spots (HK: entrance of the cross harbour tunnel, central district, …. ) – In developing countries: • Narrow streets not suitable for heavy traffic • Presence of animals on the roads (India: many cows) • Poor traffic management
Problems - 2 • Inefficiency of the Public Transport – 80% of the total demand for public transport is confined to a mere 20 hours of the week. – During rush hours each day, the rolling stock is used to capacity, but at other times, it is either under-utilized or lying idle. (pushed up fares) – Capacity pressures on buses and trains are now the norm at peak periods at all metropolitan cities. (Tokyo: rail system is overload 308% in the morning rush hours) – Off peak hour period, public transport suffer from the problem of too few passengers.
Problems - 3 • Inadequate Parking Space: – Problems in finding parking spaces in central areas. – Narrowness of streets lack of parking facilities, which creates congestion. – Prohibited parking in streets hinder shop deliveries, conversely shop deliveries hinder traffic flow in the city centre.
Problems - 4 • Safety of Pedestrians – In HK, there is average 1 person killed in road accidents each day. – Widening of roads, narrow the width of pavement. – Lessening the time of green light for pedestrians – Building flyovers and tunnels, decrease the ease of movement of the old people, children, pregnant women and handicapped people. – Developing countries: • Too many pedestrians on streets for cannot afford to travel by vehicles. • Pedestrians forms an obstruction to transport.
Solutions: • Encourage and expand the use of public transport. – Restrict the use of private cars • Imposition of road tolls, high parking fee, costly license, high purchase taxes, road pricing, …. . – Improve public transport services • Improved bus services – Set up special lanes, make bus services more reliable and comfortable. • Improved rail systems – It is an efficient massive transport – In HK, MTR and KCR accompanied by the feeder bus system have contributed to the reduction of surface traffic
Solutions - 2 • Building of ring roads and by-pass. – In HK, the Eastern Corridor from Causeway bay to Central. – In Guangzhou, Inner-ring by-pass. – There is clash of interest between improved accessibility and preserve the environment. – Objections: • Visually unattractive, noisy, source of fumes, dirts and vibration, loss of business to the shops, devaluation of the properties near a flyover.
Solution - 3 • Better town planning – To decentralize economic activities from city centre to suburbs is a way of reducing traffic congestion. – Govt. can give tax relief, cheap land monetary grant to industries to disperse to suburbs. – Population and economic development more evenly distributed and can reduce the need to travel long distance to and from work. – Building new towns. • Self-contained new towns have industrial as well residential areas aim to provide employment and better housing for people who move from the major towns to the new towns. • Other methods – Staggered working hours, building new roads, ‘park-andride’ scheme…….
Housing Problem • • Introduction Problems in western cities Problems in developing countries Solutions
Introduction • Housing problem: when people found that their home cannot fulfill the role of a home. • Restricted privacy, highly uncomfortable, inconvenient, stays at home unenjoyable. – Quantities of houses: • Not enough houses, crowded in small houses, squatter. – Quality of houses: • Fails to provide enough decent and acceptable houses. • Space available person, degree of privacy, supply of electricity and water, materials used for construction, width of streets, lighting of streets, provision of drainage system……… • It is a critical problem in a growing city. High income groups are OK, but for the poor are unsatisfactory and too many people live in congested slum or squatter areas.
• Housing problems in western cities (starting of industrialization): 19 th century – housing the workers close to their place of work. – Low-income workers were forced to live in the substandard housing in the transitional zone. – These substandard housing suffered from narrow and winding streets, poor lighting and poor sanitation. • Slums – Mostly the poor, the new immigrants, and the socially deprived and colour groups. Slums pose social problems like health hazards, delinquency, crime and social unrest.
• Housing problems in western cities England Wales: – One million houses listed as unfit to live in. • Tokyo: – Overcrowding is a serious problem – Rents are so high that few families can afford a city centre flat bigger than 6 m x 4 m. • Hong Kong: – Selling prices and rent are too high – Many household apartment less than 500 ft 2 – Buildings are pushed to vertical development for high land value. – The housing selling price was dropped 50% in 1999 compared with the peak in 1997. However, it also the
Solutions of western’s housing • problems Urban renewal: – It helps to remove the urban slums and rehouse the former residents. – Effectiveness: very slow • Some old housing are being preserved for historical and cultural. • Some owners are not willing to sell their properties. • Some try to hold out their properties for obtaining higher price. • Acquisition of land is time consuming and expensive. (Urban renewal Authorities 巿區重建局) • Develop new towns: – Encourage sub-urbanization, develop new
Housing problems in developing countries • Housing problems were shown by streetsleepers, ubiquitous slums, squatter areas, incredible high rate of overcrowding, extremely high population density. • Rapid expansion of the city population, shortage of reasonable employment and poverty lead to struggle for land housing. • Not enough cheap housing for the poor. • The poor building their own squatters on empty land shanty towns formed which grow in any available space.
Housing problems in developing countries • Slum areas have few public services (water and electricity supply, sewage facilities and proper drainage) • Houses are mere shelters made of wood, mud, straw, flattened petrol tins and even paper boxes. • There are hazards of fire, landslides, flood, crime and spread of disease.
Housing problems in developing countries • Latin America: – Shanty towns are the result of housing shortage rather than of poverty. – Slum dwellers are indeed professional people or middle class, they are living in the better shanties. • Calcutta, India: – ¾ people live in overcrowded slums. – 20 people share a lavatory. – In 1975, 1. 75 million people lived in shanty towns and 100000 were pavement dwellers.
Solutions • Clearance of shanty towns and rehousing scheme. • Effectiveness of rehousing scheme: – Many third world govt. cannot afford to undertake such scheme. (Successful cases: Hong Kong and Sinapore) • Other solutions: – Upgrading of existing shanty towns probably offer a better solution. (Lusaka in Zambia) – Development of rural areas (farming) might slow down rural-urban migration and stem the
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