CHAPTER 15

Population, Urbanization, and the EnvironmentCHAPTER 15Key Topics15-1 Population Dynamics15-2 Urbanization15-3 Environmental IssuesPopulation Dynamics

Population DynamicsDemography: the scientific study of human populationsExamines size, composition, distribution of populationsLooks at changes and causes of changes in populationsPopulation DynamicsPopulation: a group of people who share a geographic territoryVary in size from a small town to the planetPopulation DynamicsWorlds populationGrown rapidly since 1800Reached 1 billion in 18046.5 billion by 2005Expected to reach 9.4 billion by 2050Population Dynamics

Population DynamicsFertility: the number of babies born during a specific period in a particular societyCrude birth rate: the number of live births per 1,000 population in a given yearIn 2011 the CBR was 20 worldwide, 36 for Africa, and 13 for the U.S.Population DynamicsBirth rates vary within a country.In the U.S., birth rates are lower for the more affluent and those with more education.Discussion: Why are birth rates higher for some populations than others? 9Population DynamicsMortality: the number of deaths during specified period in a populationCrude death rate: the number of deaths per 1,000 people in a population in a given year2011 crude death rateWorld 8U.S. 8Some African countries 15Population DynamicsInfant mortality rates: the number of deaths among infants under 1 year of age per 1,000 live births2011 mortality rateU.S. 6South America 18Afghanistan 131Population DynamicsLife expectancy: the average number of years that people who were born at the same time will live2011 life expectancyWorld 70U.S. 78 (below at least 25 other developed countries)Discussion: What causes the differences in life expectancy and mortality rates?12Population DynamicsMigration: the movement of people into or out of a specific geographic areaPush factors: encourage people to leavePull factors: attract people to new areaExamples of push factors: war, religious persecution, unemploymentExamples of pull factors: employment opportunities, religious freedom, lower crime rates13Population DynamicsInternational migration: the movement across a national borderEmigrants move out of a countryImmigrants move into a countryInternal migration: movement within a countryPopulation DynamicsApplication Identify the type of migration and push or pull factors.Joshs family moved from Louisiana to Texas after Hurricane Katrina.After a beef plant closed in Iowa, a family moved to Minnesota in search of work.A family moved from Afghanistan to France to escape the war. Josh: internal migration, push factor: aftereffects of hurricaneBeef plant: internal migration, pull factor: employment opportunitiesAfghanistan: international migration, push factor: escape war 15Population DynamicsSex ratio: the proportion of males to females in a group100equal numbers of males and females95fewer males than females105fewer females than males Discussion: What causes the sex ratio to be different for different populations? What effects do different sex ratios have? 16Population DynamicsPopulation pyramid: a visual representation of the age and sex structure of a population at a given point in timeAllows demographers to predict future needs of a populationFor example, an aging population will require more long-term health care. 17Population Dynamics

Population DynamicsMalthusian theory: the belief that the population is growing faster than the food supply needed to sustain it (Thomas Malthus 1798)Population will outdistance food supply.Population grows geometrically.Food supply grows arithmetically.

Geometric rate (2, 4, 8 )Arithmetic rate (1, 2, 3, 4 ) 19Population DynamicsNeo-Mathusians agree that the world population is exploding beyond food supplies.Earth has become a dying planet with increasing population and pollution.Number of hungry people in the world increased to 1.02 billion in 2009. Population DynamicsDemographic transition theory: maintains the population growth is kept in check and stabilizes as countries experience economic development.Development involves industrialization, modernization, technological advancements, and urbanization. Population DynamicsStages in the demographic transition:1Preindustrial: high birth rates and high death rates2Early industrialization: high birth rates and lower death rates (population growth)3Advanced industrialization: lower birth rates and death rates (lower growth rate)4Postindustrial: low birth and death rates (stability or decrease in population)Population Dynamics

Population DynamicsZero population growth: each woman has no more than two children resulting in a stable population.Many nations are now experiencing zero population growth.Discussion: Which is correctMathusian theory or demographic transition theory? 24Urbanization

UrbanizationCity: a geographic area where a large number of people live relatively permanently and make a living through nonagricultural activitiesUrbanization: the movement of people from rural areas to citiesUrbanizationThe Industrial Revolution created a surge in urbanization as people moved to cities in search of jobs and improved living conditions.In 2008, a majority of the worlds population lived in urban areas for the first time in history.Urbanization

UrbanizationMegacities: metropolitan areas with at least 10 million inhabitantsBecoming more commonBy 2025, there will be 37 megacities in the world with 3 in the U.S.U.S. megacities: New York-Newark, Chicago, Los Angeles29UrbanizationIn U.S., the fastest growing counties are near metropolitan areas.Suburbanization: movement from cities to the areas surrounding them.More than 60% of Americans reside in suburbs.UrbanizationEdge cities: business centers that are within or close to suburban residential areasExurbs: areas of new development beyond suburbs on the fringe of urbanized areasUrbanizationUrban sprawl: the rapid, unplanned, and uncontrolled spread of urban development into neighboring regionsLoss of farmland, wildlife habitats, forests, and open recreation areasIncreased cost of purchasing and maintaining automobilesAir and water pollutionJob sprawlJob sprawl: when companies move jobs from metropolitan areas to the suburbs32UrbanizationGentrification: the process of buying and renovating houses and stores by middle-class and affluent people in downtown urban neighborhoodsRevitalizes urban areas and augments taxesResults in displacement of low-income people and small businessUrbanizationRacial segregation: as suburbs expanded, low-income African Americans were left in the central cities with few housing and employment choicesDecreasing but average black or Latino household lives in a poorer neighborhoodSuburbs are becoming ethnoburbs.Between 1999 and 2008 the suburban poor population grew by 25%.34UrbanizationSociological explanations of urbanization:How and why do cities change?How do the changes affect populations?Urbanization: FunctionalismFunctionalists developed theories of urban ecology: the study of the relationships between people and their urban environmentTheories analyzed the growth of cities into different patterns.Discussion: What aspects of city life are beneficial for the residents? What aspects of city life are problems for the residents? 36Urbanization: FunctionalismConcentric zone: city grows outward in a series of ringsSector theory: pie-shaped wedges radiate from central business districtMulti-nuclei: city contains multiple centersPeripheral: suburbs and edge cities develop through highway development Urbanization: ConflictConflict theory: heavily influenced new urban sociologyEconomic and political factors determine urban growth or decline.Urban changes are influenced by the dominant social class and powerful capitalists.Urban space is a commodity to be bought and sold. Urbanization: FeministFeminist scholars emphasize gender-related constraints.Developers ignored womens changing roles.Poor women and minorities have the least access to decent housing.Safe public transportation and other public areas are limited.Women fear for their safety in urban areas. 39Urbanization: Symbolic InteractionistsSymbolic interactionists are interested in the impact of urban life on its residents.Urbanism is a way of life characterized by tolerance of different lifestyles but superficial interaction and social isolation.Recent studies find satisfying lives for urbanites.40UrbanizationApplication Identify the theoretical perspective:People create suburbs to enhance their quality of life.Financial institutions determine the shape of cities.Urbanites are more socially isolated than those in rural areas. People create: functionalismFinancial institutions: conflictUrbanites: symbolic interaction 41Environmental Issues

Environmental IssuesEcosystem: involves a physical environment and all forms of life living in relation to one anotherEnvironmental problems threaten our ecosystem. Environmental IssuesAccess to clean water:More than 1 billion people do not have clean water.Over 3 million children die every year because of diarrheal diseases.Water-related diseases cause 50% of illnesses and deaths. Environmental IssuesThreats to water supply:Pollution:Toxins from cities, factories, and farmsThe Clean Water Act (1972) and Safe Drinking Water Act (1974) are often violated with little punishment.The Safe Drinking Water Act requires communities to deliver safe tap water. 45Environmental IssuesThreats to water supply:Privatization: transferring assets or operations of public water systems into private handsBottled water depletes local water sources and creates plastic water garbage.Environmental IssuesThreats to the water supply:MismanagementMost water-related problems are due to human mismanagement, corruption, and bureaucratic bungling.Many water and sewage pipes are old and deteriorating.Agricultural waste includes production of water-hungry crops in arid areas. Environmental IssuesThe most common sources of air pollution are:Fossil fuelsManufacturingWinds blowing contaminants to other areasGovernment policies including lack of enforcement of pollution lawEnvironmental IssuesGlobal warming: increased temperature of the earths atmosphereThe greenhouse effect: heating of the earths temperature due to atmospheric gasesEnvironmental IssuesClimate change: change of overall temperatures and water conditions over timeIncreases in ocean acidityLoss of livelihoodsCoastal erosion and loss of homesFloods and droughtsEnvironmental IssuesSustainable development: economic activities that meet the needs of the present without threatening the environmental legacy of future generationsDiscussion: Should we be optimistic or pessimistic about the environmental future? What should be done about our environmental future?51Chapter ReviewDescribe the dynamics of population.What are the concerns regarding changing population?Describe the urbanization trends.Distinguish among the sociological explanations of urbanization.What are the environmental issues facing the world?