Urban Environments

Centripetal Movements

These are movements of people into the urban areas.

Urbanisation

Definition: An increasing % of a countries population living in towns & cities.

Causes: Natural increase in urban areas or migration to urban areas.

Global Patterns

* Happening most rapidly in developing countries.  India, China, Brazil, Mexico are all facing rapid urbanisation.

* MEDCs are currently experiencing lower rates of urbanisation.  They went through rapid urbanisation in the past when they industrialised.

Rural to Urban migration

People moving from the countryside to the cities.

Push factors (reasons for leaving a place)

– Mechanisation of agriculture is causing reduced demand for labour

– Lack of range of jobs available (mainly agriculture-based).

– Lack of higher education provision & medical facilities.

– Poor infrastructure provision – phone & internet networks, electricity etc

Pull factors (attractions of the destination)

– Range of job opportunities (services, ICT, manufacturing).  higher wages

– Opportunity to establish trade in the informal sector.

– Higher education facilities & main hospitals.

– Entertainment: nightclubs, restaurants, bars, cinemas, theatres.

– More desirable housing.

Gentrification

Old and run down areas in towns and cities have been modernised in many MEDC cities.  This has involved upgrading the quality of the housing, demolishing the remnants of industries that have died or moved overseas and replacing them with new industry.

This normally involves moving the old residents out and attracting new affluent people.

Example: London Docklands.

Old ship docks & warehousing demolished & high-rise banking offices have replaced them.  The old terraced housing for the dock workers has been replaced with modern luxury apartments.

Urban Regeneration: Newcastle/Gateshead Quayside

The quayside of the River Tyne was a major industrial area through the early 20th century.  Warehouses lined the river banks, ships loaded and unloaded goods for export and import, and ships were being built in dry docks.

By the late 20th Century most of the industry had declined or moved overseas.  The quayside was a run-down area of derelict warehouses, graffiti and litter.

Since 1990 there has been significant redevelopment of these brownfield sites which has transformed the area into a vibrant leisure and recreation zone with high land values and desirable modern flats.

Restaurants, an art gallery, a concert hall, bars and cafes line the pedestrianised riverside now.

urban regeneration
urban regeneration

Counter-Urbanisation

The movement of people out of towns and cities to more rural locations.

* MEDC trend as people have more disposable income and want a different lifestyle

Push factors

– noise & air pollution in inner city areas

– higher crime rates

– traffic congestion

– lack of space for gardens and drive ways for cars

Pull factors

– ICT & internet has allowed many workers to work from home – anywhere.

– larger houses with gardens & pleasant environment.

– lower crime rates & more family friendly (safer for kids).

– ring roads and out of towns stores/shopping malls are easier to access.

– decentralisation of many industries means that many people work outside the town

Suburbanisation

* Outward growth of towns & cities which engulfs surrounding villages & rural areas.   It is the urban area growing outwards.  May even engulf other towns to form a conurbation.

Has happened in many places such as Japan:

Urban Sprawl

* Unplanned & uncontrolled growth of an urban area into the surrounding countryside.  Common in rapidly expanding urban areas (Cairo) in which authorities struggle to keep  up.

Green Belts

In the UK the government has created strips of land surrounding the major cities in which planning permission is difficult to obtain.  This is aimed at reducing continual suburbanisation.

Global Megacities

Definition: cities with populations over 10 million.

Historically the majority of megacities have been located in the more developed countries (European & N. American).

These cities have had stable of slow population growth in recent decades.

Recent years decades has seen rapid growth of cities in Brazil, India, China, as well as capital cities in many other LEDCs.

This is now where the majority of the fastest growing and largest megacities are.

2007: Sau Paulo 18.5 million, Mumbai 19 million,  Mexico City 19 million, Tokyo (conurbation) 35 million.

Residential Areas

burgessThis basic concentric ring model was developed by Burgess in 1924.  It is a very simplistic model that assumes equal resources & flat land in all directions which is just not the case in the real world.  It also omits the impact of transportation routes on industrial location.

It does however give a good generalisation of the pattern of residential areas.  Generally the poorer residents live closer to the light manufacturing (they may be manual workers) in smaller, poorer quality housing and a more built up environment.  With distance from the CBD the housing becomes larger & higher quality, has more space, gardens, driveways for cars.  The houses  are more spaced out and there is a feeling of a less built up environment.

* Obviously each urban area is different in terms of housing, ethnic diversity and the social status of its citizens.

Shanty Towns/Slums

slum

  • A characteristic of many large cities in LEDCs.  Rapid inward movement & the lack of cheap housing leads residents to build their own dwellings on illegal sites.
  • The land that shanty towns appear on has often been left empty due to it being dangerous or contaminated.
  • In Rio de Janeiro many shanty towns are on constructed on very steep unstable land that is prone to landslides in heavy rain.
  • Slum settlements are often located on the edges of urban areas and don’t have basic infrastructure (waste disposal, running potable water, electricity).

case-study-buttonCase Study: Rochina, Rio de Janeiro, Brazil

One of the older favelas in Rio, it has a relatively central location.  It is reportedly the largest favela in South America with over 120 000 residents.  Rio has in the past tried to get rid of the favela and move its residents to the outskirts of the city. This was resisted with violence by the residents and was unsuccessful.

Progress

  • In 1994, Rio accepted the existence of the favela and now locates in on maps.  This has led to a new approach to dealing with favelas:
  • Residents can now legally own houses/land in Rocinha.
  • This has led to infrastructure provision such as sewage systems, waste disposal, electricity and drinking water.
  • Buildings have been upgraded with many being constructed from brick rather than wood and mud.
  • Provision of services (electricity) has allowed residents to have proof of residence (receipt of payment) for banks & jobs.

Problems

  • Risk of floods & landslides due to its geographical location on a steep hillside.
  • Lack of policing means that social problems such as drug use, crime, lack of employment & low incomes still exist for most.

Source: http://www.geographyinthenews.rgs.org/news/article/?id=282

Economic Activity

The Central Business District

The centre of the urban area, it is divided into zones.

The central areas are the most accessible & are the busiest –  firms that desire this & can afford the rent will locate here.  Public offices that need to be accessible but don’t need prime locations locate  around the outer edges of the CBD.

Peak Land Value Intersection (PLVI)

* Located in the inner core this is often the location with the highest passing footfall and subsequently the highest value.

Traditionally businesses would locate in or around the CBD.  The ease of access for workers and customers as well as ancillary firms or support services being located close by was important.

Before the internet, firms needed to be close to post, printing and banking facilities.

Decentralisation

The movement of businesses & retail to the suburbs or edges of urban areas.

Often located at transport intersections that connect to large urban populations & have high traffic flows.

Business parks, trading estates, retail parks & shopping malls are all examples.

Push factors

Pull factors

– traffic congestion (workers and customers)

– high cost of car parking in town centres

– high land values & rents in town centres.

– lack of space for expansion & old buildings with planning

  restrictions.

– ring roads & counter-urbanisation mean consumers allow

   workers easy access.

– space for expansion, free car parking, landscaped grounds.

– cheaper land values.

– modern buildings equipped for ICT networks.

 

Computers, cell phones and the internet have transformed the way businesses operate and subsequently their locational needs.

Impact of Decentralisation

* In some cases decentralisation has led to the decline of the CBD.  Once this starts to happen, less people are attracted into the CBD for retail purposes which further exacerbates the problem.

* Out of towns retail units & business parks are often located with private car transport prioritised (car owners often have more income).  This can make these places less accessible to the poorer communities living in the inner city areas.

* The CBD has found it tough to compete with climate controlled shopping, plentiful and free car parking and a safe environment.

* CBDs have responded in many cases by pedestrianising shopping streets & improving the environment (trees, seating, sculptures).

Greenfield & Brownfield Sites

As urban areas develop and grow they experience changes in their structure and land use.  Industries decline and new ones develop.  Housing stock becomes outdated and run down in some areas and new housing is developed in other areas.

The land on which housing or industry once stood often has the derelict remains of the buildings and may even be contaminated with chemicals or other pollutants from the industrial processes.  If it has the potential for redevelopment it is called brownfield land.

Many urban areas are targeting the use of brownfield land for redevelopment in an effort to reduce urban sprawl.  The difficulty is that often it is cheaper to develop previously unused land (greenfield land).  These sites don’t need the removal of old buildings, the cleaning of the soils, removal of old groundworks (sewage pipes, water pipes, foundations).

The Informal Sector

The informal sector of the economy comprises the work that takes place but that is not registered or accounted for.  Often found extensively in LEDC cities but it does also exist in MEDC cities.

Characteristics

  • Activities such as: shoe shine, scrap metal recycling into pots & pans, car washing, household maids/cleaners.
  • In many LEDCs manufacturing work is regularly outsourced to women at home (textiles) on an informal basis.
  • Very few barriers to entry – no qualifications, proof of residence or bank account required.  Very few start up costs. No taxes paid. Often rent as it is often a small easily moved stall.
  • Often located in inner city areas, around market places or from peoples houses.

Concerns

Due to the nature of not being registered these activities are not regulated.  This leads to several issues:

  • lack of job security
  • safety of working environment & long working hours.
  • low and often inconsistent incomes.
  • inability to obtain loans from banks to expand operation/enterprise or for mortgages.
  • not having paid taxes often results in inability to access some social services.

The Urban Heat Island

  • Urban areas create islands of rising heat in relation to the surrounding rural areas.  Often 2-30C higher.
  • Dark surfaces absorb much of the incoming solar  radiation & emit it as heat.
  • Buildings release heat (internal heating/air conditioning)
  • Transport & industry emit heat.

Urban Micro-climates

  • Heat emitted by dark surfaces, buildings (internal heating), industry and transport.
  • Wind turbulence & funnelling by buildings obstructing the natural wind flow.
  • Lower humidity due to less evaporation caused by impermeable surfaces & channelling of surface water rapidly away..
  • Increased cloud formation as the pollution particles act as hygroscopic nuclei that increase condensation & water droplet formation.

Transport

Many cities (MEDC & LEDC) suffer from acute traffic congestion.  This is a often a result of rapid population expansion, increasing car ownership & city structures laid out before the rise of the motorcar.

Most MEDCs have invested in extensive & comprehensive public mass-transit transportation systems; (New York: Metro & Subway, London: Underground, Tokyo: Shinkansen bullet train).

Rapid urbanisation  in many LEDCs is outstripping infrastructure developments and leading to a heavy reliance on cars & buses.  This is causing congestion & air pollution issues.

Traffic congestion causes:

  • economic damage as it represents large amounts of time lost for workers, product deliveries & leisure/recreation time.
  • health issues – respiratory illnesses such as asthma.

Transport Management Solutions

case-study-buttonLondon: UK

cycle-hire

  • Congestion charge: Vehicles are charged a fee of £10 to enter the restricted central zones. Aimed at reducing number of vehicles on the roads in the city.
  • Bus lanes: most routes into central London have bus/taxi only lanes to speed up these services.
  • Cycle hire: bicycles can be easily & instantly hired at docking stations around the city & left at other ones.
  • London Underground: extensive underground train system that covers most of the city & has regularly been expanded to accommodate new growth areas.

 

Housing

* In many rapidly urbanising LEDCs the demand for housing is outstripping ability to increase supply.

* With demand outstripping supply it increases the price of housing which affects the poorer sections of society the most.

*This is leading to overcrowding in housing but also the development of illegal housing, squatter settlements/shanty towns.

* Urban areas in which overcrowding exists tend to overstretch the infrastructure and social services.  This can lead to inadequate education, health & police services.

* In overcrowded living conditions illnesses & disease are more easily spread.

case-study-buttonSustainable Housing, Mariners Quay, Newport, Wales

  • Built on brownfield land that used to be an industrial dock area.
  • 15 houses and 86 apartments have been built and share a biomass boiler for heating.
  • The development has 1200 m2 of photovoltaic cells (solar panels for electricity).
  • Each unit has sun boxes to capture the suns heat, triple glazed windows (energy efficiency) & water harvesting devices.
  • 62% of the building waste was re-used on site, 32% was recycled off site.
  • The development has won numerous sustainability awards since its development in.

Crime & Inequality

* Vast disparities in wealth exist in many cities, sometimes alongside each other.

* In poorer communities drug use leads to higher levels of crime.

* Urban areas tend to have higher levels of violent crime in the form of muggings and robbery.

* Johannesburg has a reputation for being dangerous with car jackings and robbery a common occurrence.

* High crime levels have led to segregation of neighbourhoods through gated communities as the wealthier residents protect themselves & their property from the poorer residents.

* Housing in San Jose, Costa Rica is often surrounded by tall fences topped with coiled razor wire, or within guarded gated communities.

Waste Overburden

case-study-buttonJardim Gramacho, Rio de Janerio, Brazil

* The largest landfill in the world – receiving the 70% of the waste from all over the city.

* The city produces more waste than can be collected and dealt with by the authorities.  There is a thriving informal sector of  the economy that goes through waste on the streets looking for recyclable materials before the waste is collected by the authorities.

* 2500 people work informally in the landfill collecting rubbish to be recycled.  This is then sold onto recycling wholesalers.

* They remove 200 tons of recyclable material each  day from the landfill.

* Without the input of the informal waste pickers, Rio’s landfills would reach capacity in a much shorter time and there would be more waste on the streets.

The City as a System

Linear System

* In this system there are large amounts of inputs that are consumed by the city & which then result in large quantities of outputs.

* Most of the solid waste generated by cities is dumped in landfill sites but these are rapidly filling up.

* Most of the waste as emissions contributes to air pollution, health issues, and acid rain.

* This is an unsustainable system since it requires endless resources and unlimited waste disposal space.  It represents a large ecological footprint.

The Circular System

* In this system the quantity of inputs has been reduced and the outputs are significantly reduced.

* The recycling of waste at various stages of consumption/use means that the city can be significantly more self sustaining and subsequently have a much smaller ecological footprint.

* There are increasing pressures on producers to reduce the amount of packaging used, to increase the energy efficiency of our appliances and transport methods and to make products more recyclable in themselves.  These steps are all reducing inputs.

Sustainable City Management

case-study-buttonCuritiba, Brazil

After rapid population expansion in the early 1960s resulted in urban sprawl, planners in Curitiba decided to plan and design the city for a more sustainable future.

Strategies

* Recycling:  It has the highest recycling rate in Brazil.  Schemes such as ‘Cambio Verde’ encourage citizens to recycle by offering fresh produce in exchange for scrap glass & metal.

* Transport: extensive & successful bus network that runs at a fraction of the cost of an underground train system.

* Open Space: with 28 parks, many of which are brownfield land reclaimed from old industry,this city has plenty of space for leisure and recreation for its citizens.

* Land zoning: zones have been created to preserve historic buildings.  Owners of historic buildings may transfer can trade them with the authority for new vacant lost elsewhere to build on, rather than demolishing historical & cultural buildings.

* Social Aspects: government subsidised essential goods are sold at low prices to the poor communities.  Converted old buses equipped as classrooms move about the poor communities offering free education & physical education programmes.

Source: http://www.pbs.org/frontlineworld/fellows/brazil1203/master-plan.html

case-study-buttonJamshedpur, India

* A rising population and falling water table initiated a more sustainable approach in Jamshedpur.

* JUSCO a private utility company has installed rainwater harvesting systems in schools, offices and housing developments.

* These systems channel the rainwater straight to underground tanks.  From here it is either used to recharge the groundwater or it is used for flushing toilets, watering gardens & washing.

* By recharging the underground water table it has increased the quality of the water and meant that clean water is available for more people.  The increase in the water quality and quantity has also decreased water borne illnesses.

* It has been so successful that it has been nominated for the U.N. Global Compact Cities pilot programme.

Source:  http://webarchive.nationalarchives.gov.uk/20110118095356/

http://www.cabe.org.uk/sustainable-places/examples/jamshedpur

case-study-buttonLondon: Sustainable Pollution Management

London is facing large fines from the European Union for failing to  achieve air quality standards.  With up to 4700 deaths in the city possibly attributed to air quality each year it is a major issue.  It has also be estimated that in heavily polluted cities life expectancy could be reduced by up to 2 years.

The Congestion Charge

* Vehicles have to pay £10 per day to enter the central areas. This is aimed at reducing the quantity of traffic & also the congestion & associated increased pollution this causes.

* Hybrid vehicles are exempt from the charge in an effort to encourage the adoption of cleaner cars.

* The money raised from the congestion charge is reinvested in public transport to increase the frequency, number of routes and comfort which will hopefully encourage more people to use it.

Successes: the charge has achieved lower levels of traffic within the zone and reduced emission levels on the main routes within the zone.  In this sense the charge has achieved a move towards a more sustainable pollution strategy.  The charge has had negative effects on businesses located within in the zone and also on residents living near the zone (parking problems).

case-study-buttonPutrajaya, Malaysia: Control of Rapid Inward Migration

* Malaysia has attempted to slow the rapid migration into its capital city Kuala Lumpur through developing a ‘Multi-media Super Corridor‘.  This aims to spread the economic growth that kuala Lumpur generates along a strip between the International airport and the City center.

* Putrajaya is the latest of the the developments & this is essentially a new town that will house all of the governments  buildings and departments.  This will relieve pressure on kuala Lumpur and allow it to specialise in commercial and business functions.

* Putrajaya will have 15 residential precincts supported with parks, schools, hospitals and other social services.  These developments should slow some of the inward migration to Kuala Lumpur as new economies and opportunities arise in Putrajaya.

* Putrajaya is being promoted as an ‘intelligent city‘ meaning that its buildings and transport systems are heavily computerised and should be energy efficient.  Its parks will include wetlands, forested areas, botanical gardens and agricultural areas in an effort to boost ecology.  In these senses Putrajaya can be used to illustrate sustainable approaches to urban development.

Source: http://www.seas.ohio.edu/44943462-2045-4D08-8B60-F218F44AA3B6/FinalDownload/DownloadId-

040A66A402CB01F5209FF45D66BE14A7/44943462-2045-4D08-8B60-F218F44AA3B6/Pdfs/Theses/Yap.pdf

Urban Ecological Footprint

* Based on the concept of the ecological footprint this is the theoretical amount of land that a cities population needs to produce the resources it consumes and to absorb its waste under current technologies.

* Urban areas due to their dense populations have large ecological footprints.

* It is estimated that London has an ecological footprint 125 times its geographical area.

* When considering urban ecological footprints it should be remembered that urban areas are more efficient than rural areas and that the more compact an urban area is, the more efficient it is.

* This is due to the reduced distance of journeys that people take.  Higher usage of public transport, less infrastructure needed per person (wires, pipes).  Higher density living also reduces energy needed for heating homes/apartments.

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