POPULATION, URBANIZATION, AND THE ENVIRONMENT

CHAPTER 15

Key Topics

15-1 Population Dynamics15-2 Urbanization15-3 Environmental Issues

Population Dynamics

Population Dynamics

Demography: the scientific study of human populations

Examines size, composition, distribution of populations

Looks at changes and causes of changes in populations

Population Dynamics

Population: a group of people who share a geographic territory

Vary in size from a small town to the planet

Population Dynamics

World’s populationGrown rapidly since 1800Reached 1 billion in 18046.5 billion by 2005Expected to reach 9.4 billion by 2050

Population Dynamics

Population Dynamics

Fertility: the number of babies born during a specific period in a particular society

Crude birth rate: the number of live births per 1,000 population in a given year

In 2011 the CBR was 20 worldwide, 36 for Africa, and 13 for the U.S.

Population Dynamics

Birth rates vary within a country.In the U.S., birth rates are lower for the more

affluent and those with more education.

Population Dynamics

Mortality: the number of deaths during specified period in a population

Crude death rate: the number of deaths per 1,000 people in a population in a given year

2011 crude death rate World 8 U.S. 8 Some African countries 15

Population Dynamics

Infant mortality rates: the number of deaths among infants under 1 year of age per 1,000 live births

2011 mortality rate U.S. 6 South America 18 Afghanistan 131

Population Dynamics

Life expectancy: the average number of years that people who were born at the same time will live

2011 life expectancy World 70 U.S. 78 (below at least 25 other developed countries)

Population Dynamics

Migration: the movement of people into or out of a specific geographic area

Push factors: encourage people to leavePull factors: attract people to new area

Population Dynamics

International migration: the movement across a national border Emigrants move out of a country Immigrants move into a country

Internal migration: movement within a country

Population Dynamics—Application

Identify the type of migration and push or pull factors.

Josh’s 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.

Population Dynamics

Sex ratio: the proportion of males to females in a group 100—equal numbers of males and females 95—fewer males than females 105—fewer females than males

Population Dynamics

Population pyramid: a visual representation of the age and sex structure of a population at a given point in time

Allows demographers to predict future needs of a population

Population Dynamics

Population Dynamics

Malthusian 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.

Population Dynamics

Neo-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 Dynamics

Demographic 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 Dynamics

Stages in the demographic transition:1—Preindustrial: high birth rates and high

death rates2—Early industrialization: high birth rates

and lower death rates (population growth)3—Advanced industrialization: lower birth

rates and death rates (lower growth rate)4—Postindustrial: low birth and death rates

(stability or decrease in population)

Population Dynamics

Population Dynamics

Zero population growth: each woman has no more than two children resulting in a stable population.

Many nations are now experiencing zero population growth.

Urbanization

Urbanization

City: a geographic area where a large number of people live relatively permanently and make a living through nonagricultural activities

Urbanization: the movement of people from rural areas to cities

Urbanization

The 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 world’s population lived in urban areas for the first time in history.

Urbanization

Urbanization

Megacities: metropolitan areas with at least 10 million inhabitants

Becoming more commonBy 2025, there will be 37 megacities in the

world with 3 in the U.S.

Urbanization

In 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.

Urbanization

Edge cities: business centers that are within or close to suburban residential areas

Exurbs: areas of new development beyond suburbs on the fringe of urbanized areas

Urbanization

Urban sprawl: the rapid, unplanned, and uncontrolled spread of urban development into neighboring regions Loss of farmland, wildlife habitats, forests, and open

recreation areas Increased cost of purchasing and maintaining

automobiles Air and water pollution Job sprawl

Urbanization

Gentrification: the process of buying and renovating houses and stores by middle-class and affluent people in downtown urban neighborhoods

Revitalizes urban areas and augments taxesResults in displacement of low-income people

and small business

Urbanization

Racial segregation: as suburbs expanded, low-income African Americans were left in the central cities with few housing and employment choices

Decreasing but average black or Latino household lives in a poorer neighborhood

Suburbs are becoming “ethnoburbs.”

Urbanization

Sociological explanations of urbanization:How and why do cities change?How do the changes affect populations?

Urbanization: Functionalism

Functionalists developed theories of urban ecology: the study of the relationships between people and their urban environment

Theories analyzed the growth of cities into different patterns.

Urbanization: Functionalism

Concentric zone: city grows outward in a series of rings

Sector theory: pie-shaped wedges radiate from central business district

Multi-nuclei: city contains multiple centersPeripheral: suburbs and edge cities develop

through highway development

Urbanization: Conflict

Conflict theory: heavily influenced new urban sociology

Economic 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: Feminist

Feminist scholars emphasize gender-related constraints.

Developers ignored women’s changing roles.Poor women and minorities have the least

access to decent housing.Safe public transportation and other public

areas are limited.

Urbanization: Symbolic Interactionists

Symbolic 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.

Urbanization—Application

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.

Environmental Issues

Environmental Issues

Ecosystem: involves a physical environment and all forms of life living in relation to one another

Environmental problems threaten our ecosystem.

Environmental Issues

Access 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 Issues

Threats to water supply:Pollution:

Toxins from cities, factories, and farms The Clean Water Act (1972) and Safe Drinking Water

Act (1974) are often violated with little punishment.

Environmental Issues

Threats to water supply:Privatization: transferring assets or

operations of public water systems into private hands

Bottled water depletes local water sources and creates plastic water garbage.

Environmental Issues

Threats to the water supply:Mismanagement

Most 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 Issues

The most common sources of air pollution are:Fossil fuelsManufacturingWinds blowing contaminants to other areasGovernment policies including lack of

enforcement of pollution law

Environmental Issues

Global warming: increased temperature of the earth’s atmosphere

The greenhouse effect: heating of the earth’s temperature due to atmospheric gases

Environmental Issues

Climate change: change of overall temperatures and water conditions over time

Increases in ocean acidityLoss of livelihoodsCoastal erosion and loss of homesFloods and droughts

Environmental Issues

Sustainable development: economic activities that meet the needs of the present without threatening the environmental legacy of future generations

Chapter Review

1. Describe the dynamics of population.2. What are the concerns regarding changing

population?3. Describe the urbanization trends.4. Distinguish among the sociological

explanations of urbanization.5. What are the environmental issues facing

the world?