2 Chapter Overview Questions How is the world’s population distributed between rural and urban areas, and what factors determine how urban areas develop?What are the major resource and environmental problems of urban areas?How do transportation systems shape urban areas and growth, and what are the advantages and disadvantages of various forms of transportation?
3 Chapter Overview Questions (cont’d) What methods are used for planning and controlling urban growth?How can cities be made more sustainable and more desirable places to live?
4 Core Case Study: The Ecocity Concept in Curitiba, Brazil 70% of Curitiba’s 2 million people use the bus system.Only high-rise apartments are allowed near bus routes and devote the bottom 2 floors to stores.Bike paths run through the city.Cars are banned from 49 blocks of the city’s downtown.
5 Core Case Study: The Ecocity Concept in Curitiba, Brazil This bus system moves large numbers of passengers based on its infrastructure:Express lanes for buses only.Double and triple length buses.Extra-wide doors for easy boarding.Figure 23-1
6 City centerFigure 23.1Solutions: bus system in Curitiba, Brazil. This system moves large numbers of passengers around rapidly because each of the five major spokes has two express lanes used only by buses. Double- and triple-length bus sections are hooked together as needed to carry up to 300 passengers. Boarding is speeded up by the use of extra-wide doors and raised tubes that allow passengers to pay before getting on the bus (top left).RouteExpressInterdistrictDirectFeederWorkersFig. 23-1, p. 548
7 URBANIZATION AND URBAN GROWTH People move to cities because “push” factors force them out of rural areas and “pull” factors give them the hope of finding jobs and a better life in the city.Urban populations are growing rapidly and many cities in developing countries have become centers of poverty.
8 Major Urban Areas of the World Satellite images of the earth at night showing city lights. Currently, 49% of the world’s population live in urban areas (2% of earth’s land area).Figure 23-2
9 Dhaka million millionKarachi million millionBeijing million millionLos Angeles million millionTokyo million millionNew York million millionCairo million millionMumbai (Bombay) million millionCalcutta million millionOsaka million millionMexico City million millionSao Paulo million millionManila million millionLagos million millionJakarta million millionDelhi million millionKeyShanghai million millionFigure 23.2Global outlook: major urban areas throughout the world revealed in satellite images of the earth at night showing city lights. Currently, the 47.5% of the world’s people living in urban areas occupy about 2% of the earth’s land area. Note that most of the world’s urban areas are found along the coasts of continents, and most of Africa and much of the interior of South America, Asia, and Australia are dark at night. This figure also shows the populations of the world’s 18 megacities (each with 10 million or more people) in 2006 and their projected populations in All but three are located in developing countries. QUESTION: In order, what were the world’s five most populous cities in 2006 and the five most populous ones projected for 2015? (Data from National Geophysics Data Center, National Oceanic and Atmospheric Administration, and United Nations)Buenos Aires million million2004 (estimated)2015 (projected)Fig. 23-2, p. 550
10 Case Study: Urbanization in the U.S. 8 of 10 Americans live in Urban areas.About 48% of Americans live in consolidated metropolitan areas (bottom map).Figure 23-4
11 Urban SprawlWhen land is available and affordable, urban areas tend to sprawl outward because:Federal government loan guarantees stimulated the development of suburbs.Low-cost gasoline and government funding of highways encourages automobile use.Tax-laws encourage home ownership.Most zoning laws separate residential and commercial use of land.Many urban areas lack proper planning.
12 Urban SprawlUrban sprawl in and around Las Vegas, Nevada between 1973 and 2000.Figure 23-5
13 Urban SprawlAs they grow and sprawl outward, urban areas merge to form megalopolis.Bowash runs from Boston, Massachusetts to Washington, D.C.Figure 23-7
16 BrownfieldBrownfields - Contaminated properties that have been abandoned or are not being used up to potential because of pollution concerns.Up to one-third of all commercial industrial sites in urban core of many big cities fall into this category. Steel Yard Commons. In many cases, property owners complain that unreasonably high purity levels are demanded in remediation programs.
17 Natural Capital Degradation Urban SprawlLand and BiodiversityHuman Health and AestheticsWaterEnergy, Air, and ClimateEconomic EffectsIncreased runoffLoss of croplandContaminated drinking water and airIncreased surface water & groundwater pollutionIncreased energy use & wasteHigher taxesLoss of forests and grasslandsIncreased air pollutionDecline of downtown business districtsIncreased use of surface water and groundwaterLoss of wetlandsFigure 23.6Natural capital degradation: some undesirable impacts of urban sprawl or car-dependent development. QUESTION: Which five of these effects do you think are the most harmful?Weight gainIncreased greenhouse gas emissionsLoss and fragmentation of wildlife habitatsNoise pollutionDecreased storage of surface water and groundwaterIncreased unemployment in central citySky illumination at nightEnhanced global warmingIncreased wildlife roadkillIncreased floodingWarmer microclimate (urban heat island effect)Increased soil erosionTraffic congestionDecreased natural sewage treatmentLoss of tax base in central cityFig. 23-6, p. 553
18 URBAN RESOURCE AND ENVIRONMENTAL PROBLEMS Urban areas can offer more job opportunities and better education and health, and can help protect biodiversity by concentrating people.
19 URBAN RESOURCE AND ENVIRONMENTAL PROBLEMS Cities are rarely self-sustaining, can threaten biodiversity, lack trees, concentrate pollutants and noise, spread infectious diseases, and are centers of poverty crime, and terrorism.Figure 23-3
20 URBAN RESOURCE AND ENVIRONMENTAL PROBLEMS Urban areas rarely are sustainable systems.Figure 23-8
21 InputsOutputsEnergySolid wastesNoiseFoodWaste heatWaterWealthRaw materialsAir pollutantsManufactured goodsIdeasWater pollutantsMoneyManufactured goodsInformationFigure 23.8Natural capital degradation: urban areas rarely are sustainable systems. The typical city depends on large nonurban areas for huge inputs of matter and energy resources and for large outputs of waste matter and heat. According to an analysis by Mathis Wackernagel and William Rees, an area 58 times as large as that of London, England, is needed to supply its residents with resources. They estimate that meeting the needs of all the world’s people at the same rate of resource use as that of London would take at least three more earths.Greenhouse gasesFig. 23-8, p. 554
22 URBAN RESOURCE AND ENVIRONMENTAL PROBLEMS Noise levels of some common sounds. Prolonged exposure to lower noise levels and occasional loud sounds can greatly increase internal stress.Figure 23-9
23 Permanent damage begins after 8-hour exposure Noise Levels (in dbA)Normal breathingQuiet rural areaRainfallVacuum cleanerLawn mowerRock musicEarphones at loud levelBoom carsFigure 23.9Noise levels (in decibel-A sound pressure units) of some common sounds. You are being exposed to a sound level high enough to cause permanent hearing damage if you need to raise your voice to be heard above the racket, if a noise causes your ears to ring, or if nearby speech seems muffled. Prolonged exposure to lower noise levels and occasional loud sounds may not damage your hearing but can greatly increase internal stress.WhisperQuiet roomNormal conversationAverage factoryChain sawThunder-clap (nearby)Air raid sirenMilitary rifleFig. 23-9, p. 555
24 URBAN RESOURCE AND ENVIRONMENTAL PROBLEMS Extreme poverty forces hundreds of millions of people to live in slums and shantytowns where adequate water supplies, sewage disposal, and other services do not exist.Figure 23-10
25 How Would You Vote?To conduct an instant in-class survey using a classroom response system, access “JoinIn Clicker Content” from the PowerLecture main menu for Living in the Environment.Should squatters around cities of developing countries be given title to land they live on?a. No. No one has the right to steal and pollute public or private lands.b. Yes. The poor need homes.
26 TRANSPORTATION AND URBAN DEVELOPMENT Land availability determines whether a city must grow vertically or spread out horizontally and whether it relies mostly on mass transit or the automobile.If Americans doubled their use of mass transit from 5% to 10%, this would reduce U.S. dependence on oil by 40%.
27 TRANSPORTATION AND URBAN DEVELOPMENT Motor vehicles provide personal benefits and promote economic growth, but also kill and injure many people, pollute the air, promote urban sprawl, and result in traffic jams.Although it would not be politically popular, we could reduce reliance on automobiles by having users pay for their harmful effects.
28 Solutions: Redesigning Urban Transport Alternatives include walking, bicycling, and taking subways, trains, and buses.
29 How Would You Vote?To conduct an instant in-class survey using a classroom response system, access “JoinIn Clicker Content” from the PowerLecture main menu for Living in the Environment.Should half the U.S. gasoline tax be used to develop mass transit, bike lanes, and other alternatives to the car?a. No. Money needed to repair roads and bridges should not be spent on bike paths and other projects that few people would use.b. Yes. Encouraging alternatives to personal vehicles will decrease pollution and save energy.
30 Little protection in an accident Affordable Trade-OffsBicyclesAdvantagesDisadvantagesLittle protection in an accidentAffordableProduce no pollutionDo not protect riders from bad weatherQuietRequire little parking spaceNot practical for trips longer than 8 kilometers (5 miles)Easy to maneuver in trafficFigure 23.11Trade-offs: advantages and disadvantages of bicycles. QUESTION: Which single advantage and which single disadvantage do you think are the most important?Take few resources to makeCan be tiring (except for electric bicycles)Very energy efficientLack of secure bike parkingProvide exerciseFig , p. 560
31 More energy efficient than cars Expensive to build and maintain Trade-OffsMass Transit RailAdvantagesDisadvantagesMore energy efficient than carsExpensive to build and maintainProduces less air pollution than carsCost-effective only along a densely populated narrow corridorRequires less land than roads and parking areas for carsFigure 23.12Trade-offs: advantages and disadvantages of mass transit rail systems in urban areas. QUESTION: Which single advantage and which single disadvantage do you think are the most important?Commits riders to transportation schedulesCauses fewer injuries and deaths than carsCan cause noise and vibration for nearby residentsReduces car congestion in citiesFig , p. 560
32 More flexible than rail system Trade-OffsBusesAdvantagesDisadvantagesMore flexible than rail systemCan lose money because they need low fares to attract ridersCan be rerouted as neededOften get caught in traffic unless operating in express lanesCost less to develop and maintain than heavy-rail systemFigure 23.13Trade-offs: advantages and disadvantages of bus systems in urban areas. QUESTION: Which single advantage and which single disadvantage do you think are the most important?Commits riders to transportation schedulesCan greatly reduce car use and pollutionNoisyFig , p. 561
33 Can reduce travel by car or plane Expensive to run and maintain Trade-OffsRapid RailAdvantagesDisadvantagesCan reduce travel by car or planeExpensive to run and maintainIdeal for trips of 200–1,000 kilometers (120–620 miles)Must operate along heavily used routes to be profitableFigure 23.14Trade-offs: advantages and disadvantages of rapid-rail systems between urban areas. QUESTION: Which single advantage and which single disadvantage do you think are the most important?Much more energy efficient per rider over the same distance than a car or planeCauses noise and vibration for nearby residentsFig , p. 561
34 Solutions: Redesigning Urban Transport Potential routes for high-speed bullet trains in the U.S and parts of Canada.Figure 23-15
35 Case Study: Destroying a Great Mass Transit System in the U.S. In the early 1900s, the U.S. had one of the world’s best street car systems.It was bought and destroyed by companies to sell cars and buses.At the same time, National City Lines worked to convert electric-powered commuter locomotives to diesel-powered ones.
36 URBAN LAND-USE PLANNING AND CONTROL Most land-use planning in the U.S leads to poorly controlled urban sprawl and fund this often environmentally destructive process with property taxes.Smart growth can help control growth patterns discourage urban sprawl, reduce car dependence, and protect ecologically sensitive areas.
37 Limits and Regulations Limit building permits Urban growth boundaries SolutionsSmart Growth ToolsLimits and RegulationsLimit building permitsUrban growth boundariesGreenbelts around citiesPublic review of new developmentProtectionPreserve existing open spaceBuy new open spaceBuy development rights that prohibit certain types of development on land parcelsTaxesTax land, not buildingsTax land on value of actual use (such as forest and agriculture) instead of highest value as developed landZoningEncourage mixed useConcentrate development along mass transportation routesPromote high-density cluster housing developmentsTax BreaksFor owners agreeing legally to not allow certain types of development (conservation easements)For cleaning up and developing abandoned urban sites (brownfields)Figure 23.16Solutions: smart growth or new urbanism tools used to prevent and control urban growth and sprawl. QUESTIONS: Which five of these tools do you think are the most important ways to prevent or control urban sprawl? Which, if any, of these tools are being used in your community?PlanningEcological land-use planningEnvironmental impact analysisIntegrated regional planningState and national planningRevitalization & New GrowthRevitalize existing towns & citiesBuild well-planned new towns and villages within citiesFig , p. 563
38 Case Study: Land-Use Planning in Oregon Oregon has a comprehensive land-use planning process:Permanently zone all rural land as forest, agriculture, or urban land.Draw an urban growth line around each community.Place control over land-use planning in State hands.
39 MAKING URBAN AREAS MORE SUSTAINABLE AND DESIREABLE PLACES TO LIVE There is a growing movement to create mixed-use villages and neighborhoods within urban areas where people can live, work and shop close to their homes.
40 Cluster DevelopmentHigh density housing units are concentrated on one portion of a parcel with the rest of the land used for commonly shared open space.Figure 23-17
41 Creek Undeveloped land Marsh Fig. 23-17a, p. 565 Figure 23.17 Conventional and cluster housing developments as they might appear if constructed on the same land area. With cluster development, houses, town houses, condominiums, and two- to six-story apartments are built on part of the tract. The rest, typically 30–50% of the area, is left as open space, parks, and cycling and walking paths.Fig a, p. 565
42 Typical housing development Figure 23.17Conventional and cluster housing developments as they might appear if constructed on the same land area. With cluster development, houses, town houses, condominiums, and two- to six-story apartments are built on part of the tract. The rest, typically 30–50% of the area, is left as open space, parks, and cycling and walking paths.Fig b, p. 565
43 Cluster housing development Creek PondFigure 23.17Conventional and cluster housing developments as they might appear if constructed on the same land area. With cluster development, houses, town houses, condominiums, and two- to six-story apartments are built on part of the tract. The rest, typically 30–50% of the area, is left as open space, parks, and cycling and walking paths.Fig c, p. 565
44 The Ecocity ConceptAn ecocity allows people to walk, bike, or take mass transit for most of their travel, and it recycles and reuses most of its wastes, grows much of its own food, and protects biodiversity by preserving surrounding land.
45 The Ecocity Concept Principles of sustainability: Build cities for people not cars.Use renewable energy resources.Use solar-power living machines and wetlands for waste water treatment.Depend largely on recycled water.Use energy and matter efficiently.Prevent pollution and reduce waste.Reuse and recycle at least 60% of municipal solid waste.
46 The Ecocity ConceptProtect biodiversity by preserving, protecting, and restoring surrounding natural areas.Promote urban gardens and farmers markets.Build communities that promote cultural and economic diversity.Use zoning and other tools to keep the human population and environmentally sustainable levels.