Environmental Problems, Their Causes, and Sustainability 1

Image provided courtesy of theU.S. Geological Survey1952 19671972 1995Figure 25-5 Urban sprawl in and around Las Vegas, Nevada,1952–1995—a process that has continued. Between 1970 and 2004,the population of water-short Clark County which includes Las Vegasmore than quadrupled from 463,000 to 2 million. The growth is expectedto continue but may be limited by lack of water (Spotlight,p. 326).the development of once-inaccessible outlying tracts ofland that were affordable for many Americans.Fourth, tax laws encouraged home ownership byallowing deduction of interest on home loans from incometaxes. Fifth, most state and local zoning lawsrequired large residential lots and separation of residentialand commercial use of land in new communities.Sixth, most urban areas consist of numerous politicaljurisdictions, which rarely work together to developan overall plan for managing and controllingurban growth and sprawl. In a nutshell, urban sprawl isthe product of affordable land, automobiles, cheap gasoline,and poor urban planning.Figure 25-6 shows some of the undesirable consequencesof urban sprawl. Look carefully at this figure.Urban sprawl has increased travel time in automobiles,decreased energy efficiency, increased urbanflooding problems, and destroyed prime cropland,forests, open space, and wetlands. It has also led to theeconomic decline of many central cities.To pay for heavily mortgaged houses and cars,adults in a typical suburban family have to spendMALLLand and BiodiversityLoss of croplandLoss of forests and grasslandsLoss of wetlandsLoss and fragmentation ofwildlife habitatsIncreased wildlife roadkillIncreased soil erosionHuman Healthand AestheticsContaminated drinking waterand airWeight gainNoise pollutionSky illumination at nightTraffic congestionWaterIncreased runoffIncreased surface water andgroundwater pollutionIncreased use of surface waterand groundwaterDecreased storage of surfacewater and groundwaterIncreased floodingDecreased natural sewagetreatmentYour ShopEnergy, Air, and ClimateIncreased energy useand wasteIncreased air pollutionIncreased greenhouse gasemissionsEnhanced global warmingWarmer microclimate(heat island effect)Economic EffectsHigher taxesDecline of downtownbusiness districtsIncreased unemploymentin central cityLoss of tax base in central cityFigure 25-6 Someundesirable impactsof urban sprawl or cardependentdevelopment.Do you live inan area suffering fromurban sprawl?http://biology.brookscole.com/miller14567