Presentation on theme: "Population, Resources, and Sustainability"— Presentation transcript:
1 Population, Resources, and Sustainability Chapter 10Population, Resources, and Sustainability
2 Key QuestionsHow is population size affected by the number of males and females at each age level?How can population growth be slowed?What success have India and China had in slowing population growth?How can global population growth be reduced?
3 How is Population Size Affected by Birth and Death Rates? Population size depends on: births, deaths, and migrationPopulation change = (births + immigration) – (deaths + emigration)When births and immigration are more than deaths and emigration, population is growingWhen deaths and emigration are more than births and immigration, population is declining
4 How Do We Find Birth and Death Rates? Crude birth rate: number of live births per 1,000 people in a population in a yearCrude death rate: number of deaths per 1,000 people in a population in a year
6 Some FactsEvery time your heart beats, 2.3 more babies are added to the world’s populationMore births are occurring than deathsWe share the earth’s resources with 216,000 more people each dayEquivalent of filling up a jumbo jet with 400 new passengers every 2.7 minutes!
7 Calculate the World’s Annual Population Change Annual rate of population change (%) = birth rate – death rate x 1001,000 people= birth rate – death rate10
8 <1% 1-1.9% 2-2.9% 3+% Data not available Annual world population growth<1%1-1.9%2-2.9%3+%Data notavailable
9 MapAn exponential growth rate of 1.28% may seem small, but it adds about 79 million people per year to the world’s population!Equivalent to adding a New York City every month!
10 Population in billions 2.5102.081.56Population in billionsGrowth rate (percent)1.040.520.019501960197019801990200020102020203020402050YearLess developed countriesMore developed countries
11 World’s 10 Most Populous Countries China and India together make up 37% of the world’s populationThe US has the 3rd largest population, but only 4.6% of the world’s people
13 How have Global Fertility Rates Changed? 1. Replacement fertility: number of children a couple must have to replace themselvesSlightly higher than 2 in developed countries and 2.5 in most developing countriesReason? Some female children die before reproductive years
14 How have Global Fertility Rates Changed? 2. Total Fertility Rate: estimate of the average number of children a female will have during her childbearing yearsTFRs have sharply dropped since 1950
16 Births per thousand population 3230282624Births per thousand population222018End of World War II16Demographictransition14DepressionBaby boomBaby bustEcho baby boom19101920193019401950196019701980199020002010Year
17 U.S. Birth Rates Fell Sharply because… Demographic transition:Industrialization and urbanizationEducated women working outside homeTHEN,Baby Boom Period: after WW1Echo Boom Period: people born during baby boom started having children
18 What Factors Affect Birth Rates? Importance of children as part of labor forceUrbanizationCost of raising childrenEmployment opportunities for womenInfant mortality rateAverage age at marriageAvailability of abortionsAvailability of birth controlReligious beliefs, traditions, and cultural norms
19 What Factors Affect Death Rates? Food supply and distributionNutritionImprovements in medical technologyImprovements in sanitization and personal hygieneSafer water supplies
20 Life ExpectancyAverage number of years a newborn infant can be expected to liveIn the world’s poorest countries, life expectancy is 55 years or less.High infant mortality rate = not enough food, malnutrition, or high infectious diseases
22 Infant Mortality and Birth Rates U.S. has the highest teen pregnancy rate of any developed country.Each year, 872,000 teenage girls become pregnant and 253,000 have abortionsBabies born to teenage mothers usually have low birth weight which causes infant mortality.
23 What Are Age Structure Diagrams? Age structure: the proportion of the population at each age levelPlot percentages of males and females in the population in each of 3 categories:Prereproductive: ages 0-14Reproductive: ages 15-44Postreproductive: ages 45 and up
29 What Are Some Effects of Population Decline from Reduced Fertility? As the % of people over 60 increases, more countries will experience population declinesBy 2020, 1 billion people will be 60 or older.Rapid population decline can lead to serious economic and social problemsExample: older people consume a large part of medical care, Social Security, and other services funded by taxpayerslabor shortages
30 What Are Some Effects of Population Decline from Rise in Death Rates? Sharp drop in life expectancyLoss of most productive young adult workersSharp rise in number of orphansWe need to:Reduce the spread of HIVProvide debt relief and financial assistanceSend volunteer teachers and social workers
31 Is the World Overpopulated? Is it already overpopulated?What should we do to stop population growth?What is the optimum sustainable population?No one knows!
32 One Viewpoint The world can support billions more people People are the world’s most valuable resource for solving problems and stimulating economic growth by being consumersPopulation regulation is a violation of personal freedom
33 An Opposing ViewpointWe already fail to provide the basic necessities to 1 out of 5 people todayIf we do not take measures to drop the birth rate, we are increasing the death rateWe greatly increase environmental harm
34 Stages of Development in Countries Preindustrial: very little population growth due to harsh living conditionsTransitional: industrialization begins; food production rises and health care improves; population grows rapidlyIndustrial: birth rate drops; population growth slowsPostindustrial: birth rate declines; zero population growth
35 How Do We Cut Global Population Growth? Family planningEmpowering women: women have fewer and healthier children when they have access to education and paying jobs AND when they live in societies with rightsReduce poverty