Page 230 - Environment: The Science Behind the Stories

Reviewing Objectives

you should now be able to: outline and assess the concept of
demographic transition
Perceive the scope of human population growth • The demographic transition model explains why popula-
tion growth has slowed in industrialized nations. Industri-
• Our global population of nearly 7 billion people adds alization and urbanization reduce the economic need for
over 70 million people per year (>2 people every second). children, and education and the empowerment of women
(p. 208)
decrease unwanted pregnancies. Parents in developed
• The global population growth rate peaked at 2.1% in the nations choose to invest in quality of life rather than quan-
1960s and now stands at 1.2%. Growth rates vary among tity of children. (pp. 219–220)
regions. (p. 209)
• The demographic transition may or may not proceed to
completion in all of today’s developing nations. Whether
Assess divergent views on population growth it does is of immense importance in the quest for sustain-
• Thomas Malthus and Paul Ehrlich warned that overpopula- ability. (p. 220)
tion would deplete resources and harm humanity, whereas
Cornucopians see little to fear in population growth (p. 210) Describe how family planning, the status of women,
and wealth and poverty affect population growth
• Rising population can deplete resources, intensify pollu-
tion, stress social systems, and degrade ecosystems, such • Many birth control methods serve to reduce unwanted
that environmental quality and our quality of life decline. pregnancies. (p. 221)
(p. 210)
• Family-planning programs and reproductive education
• Population decline and population aging in some nations have reduced population growth in many nations. (p. 224)
have given rise to fears of economic decline. (pp. 210–211)
• When women are empowered and achieve equality with
men, fertility rates fall, and children tend to be better cared
Evaluate how human population, affluence, for, healthier, and better educated. (p. 224)
and technology affect the environment
• Poorer societies tend to show faster population growth than
• The IPAT model summarizes how environmental impact do wealthier societies. (p. 225)
(I) results from interactions among population size (P),
affluence (A), and technology (T). (p. 211) • The intensive consumption of affluent societies often
makes their ecological impact greater than that of poorer
• Rising population and rising affluence may each increase nations with larger populations. (pp. 225–226)
consumption and environmental impact. Technology has
frequently worsened environmental degradation, but it can Characterize the dimensions of the HIV/AIDs epidemic
also help mitigate our impacts. (pp. 211–213)
• About 34 million people worldwide are infected with HIV,
Explain and apply the fundamentals of demography and 2 million die from AIDS each year. Most live in sub-
Saharan Africa. (pp. 226–227)
• Demography applies principles of population ecology to
the statistical study of human populations. (p. 214) • Epidemics that claim many young and productive members
of society influence population dynamics and can have
• Demographers study size, density, distribution, age struc- severe social and economic ramifications. (p. 227)
ture, and sex ratios of populations, as well as rates of birth,
death, immigration, and emigration. (pp. 214–218) • We may at last be turning the corner on HIV/AIDS, thanks
to a multifaceted effort. (p. 227)
• Total fertility rate (TFR) contributes greatly to change in
population size. (pp. 218–219) CHAPTER 8 • Hum A n Po P ul AT i on

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