Applying Population Ecology: Human Population and Urbanization Chapter 7

Curitiba, Brazil Fig. 7-1, p. 123

7-1 How Many People Can the Earth Support? We do not know how long we can continue increasing the earth’s carrying capacity for humans without seriously degrading the life-support systems for us and many other species.

Human Population Explosion Exponential growth (J-curve) in past 200 years Exponential growth (J-curve) in past 200 years Three major reasons Three major reasons Ability to expand into diverse habitats Ability to expand into diverse habitats Emergence of agriculture (Green Revolution) Emergence of agriculture (Green Revolution) Sanitation systems and control of infectious diseases Sanitation systems and control of infectious diseases

How Long Can the Human Population Grow Rate slowing, but still exponential Rate slowing, but still exponential Uneven global growth Uneven global growth No population can grow indefinitely No population can grow indefinitely 2050 global estimates: 7.2–10.6 billion people 2050 global estimates: 7.2–10.6 billion people 97% growth in developing countries, least likely to cope 97% growth in developing countries, least likely to cope

Human Alteration of the Environment

Are There Too Many of Us? Resources for growing population??? Resources for growing population??? Positive viewpoint Positive viewpoint Technological solutions Technological solutions Growing population a value resource Growing population a value resource Negative viewpoint Negative viewpoint 20% currently lack necessities 20% currently lack necessities Declining conditions increase death rate Declining conditions increase death rate Resource use already degrade environment Resource use already degrade environment Optimum sustainable population Optimum sustainable population What is it??? What is it??? Cultural carrying capacity = unknown Cultural carrying capacity = unknown

UN World Population Projections Fig. 7-3, p. 126

What Factors Influence Population Size? Concept 7-2A Population size increases because of births and immigration and decreases through deaths and emigration. Concept 7-2A Population size increases because of births and immigration and decreases through deaths and emigration. Concept 7-2B Total fertility rate is the key factor that determines the population size. Concept 7-2B Total fertility rate is the key factor that determines the population size.

Population Change Population change = Population change = (births + immigration) - (deaths + emigration) Demographers look at birth rates and death rates Demographers look at birth rates and death rates

Number of Children Fertility rates affect population size and growth rate Fertility rates affect population size and growth rate Replacement-level fertility rate (2.1) Replacement-level fertility rate (2.1) Total fertility rate (TFR) Total fertility rate (TFR)

Most Populous Countries

Current and Projected Population Sizes by Region Animations/size_region.html

U.S. Population Quadrupled in 100 years, despite oscillations in TFR Quadrupled in 100 years, despite oscillations in TFR Baby boom: High TFR Baby boom: High TFR Current births outnumbering deaths and legal immigration Current births outnumbering deaths and legal immigration Growing faster than other developed countries Growing faster than other developed countries

Fertility Rate of the U.S. Population

Changes in the U.S. Population

Global Factors Affecting Birth Rates (+) = increase rates(-) = decrease rates Children as part of labor force (+) Children as part of labor force (+) Cost of raising and educating children (-) Cost of raising and educating children (-) Availability of retirement systems (-) Availability of retirement systems (-) Urbanization (-) Urbanization (-) Educational and employment opportunities for women (-) Educational and employment opportunities for women (-) Infant mortality rate (+) Infant mortality rate (+) Average marriage age (-) Average marriage age (-) Availability of legal abortion and reliable birth control methods (-) Availability of legal abortion and reliable birth control methods (-) Religious beliefs, traditions, cultural norms (+) Religious beliefs, traditions, cultural norms (+)

Factors Affecting Death Rates Average life expectancy increased Average life expectancy increased Population growth also response to decline in crude death rate Population growth also response to decline in crude death rate Life expectancy and infant mortality rate important indicators of overall health Life expectancy and infant mortality rate important indicators of overall health Infant mortality – barometer of a society’s quality of life Infant mortality – barometer of a society’s quality of life

Migration Migration driven by economic desires (land of opportunity) Migration driven by economic desires (land of opportunity) Other reasons Other reasons Religious persecution Religious persecution Political oppression Political oppression Ethnic conflicts Ethnic conflicts Wars Wars Environmental degradation Environmental degradation

The United States Nation of immigrants Nation of immigrants 1820–1960: Most immigrants European 1820–1960: Most immigrants European Since 1960 Since 1960 Latin America – 53% Latin America – 53% Asia – 25% Asia – 25% Europe – 14% Europe – 14%

The United States Opponents of immigration Opponents of immigration Stabilize population sooner Stabilize population sooner Reduce growing environmental impact Reduce growing environmental impact 60% of population favor reducing immigration 60% of population favor reducing immigration Proponents of immigration Proponents of immigration Important historical role Important historical role Do menial jobs and pay taxes Do menial jobs and pay taxes Add cultural vitality Add cultural vitality Replace retiring baby boomers Replace retiring baby boomers

Legal Immigration

7-3 How Does a Population’s Age Structure Affect Its Growth or Decline? Concept 7-3 The numbers of males and females in young, middle, and older age groups determine how fast populations grow or decline. Concept 7-3 The numbers of males and females in young, middle, and older age groups determine how fast populations grow or decline.

Age Structure Distribution of population Distribution of population Prereproductive Prereproductive Reproductive Reproductive Postreproductive Postreproductive Country with many young people grows rapidly Country with many young people grows rapidly Country with many older people will decline Country with many older people will decline Developing countries >30% under 15 years old Developing countries >30% under 15 years old

Fig. 7-8, p. 131 Declining Germany Bulgaria Russia Male Female Male Female Male Female MaleFemale Expanding Rapidly Guatemala Nigeria Saudi Arabia Expanding Slowly United States Australia China Stable Japan Italy Greece Population Age Structures

Examples of Age Structure Animations/age_by_country.html

Global Connections Fig. 7-9, p. 132

Age Structure Predicts the Future 50% of U.S. population baby boomers 50% of U.S. population baby boomers Graying of America Graying of America 2043 – 25% of population over – 25% of population over 65 Changes the economy Changes the economy

Fig. 7-10, p. 132 Stepped Art Tracking the Baby Boomers

Declines Occur in Aging Populations “Baby bust” or “birth dearth” – TFR below 1.5 children per couple “Baby bust” or “birth dearth” – TFR below 1.5 children per couple Labor shortages Labor shortages Strain on governments for public services Strain on governments for public services Fewer taxpayers Fewer taxpayers

Rising Death Rate: The AIDS Tragedy Disrupts social, economic structure Disrupts social, economic structure Removes productive young adults Removes productive young adults Next 50 years, 278 million will die (mostly African) Next 50 years, 278 million will die (mostly African) Eight African countries 16–39% infected adults Eight African countries 16–39% infected adults Life expectancy 30–40 years Life expectancy 30–40 years

7-4 How Can We Slow Population Growth? Concept 7-4 Experience indicates that the most effective ways to slow population growth are to invest in family planning, to reduce poverty, and to elevate the status of women. Concept 7-4 Experience indicates that the most effective ways to slow population growth are to invest in family planning, to reduce poverty, and to elevate the status of women.

Stages of Demographic Transition Preindustrial Preindustrial Transitional – demographic trap Transitional – demographic trap Industrial Industrial Postindustrial Postindustrial

Stages of Demographic Transition

Fig. 7-12, p. 134 Death rate Stage 1 Preindustrial Stage 2 Transitional Stage 3 Industrial Stage 4 Postindustrial Population grows rapidly because birth rates are high and death rates drop because of improved food production and health Population growth slows as both birth and death rates drop because of improved food production, health, and education Population growth levels off and then declines as birth rates equal and then fall below death rates Population grows very slowly because of a high birth rate (to com- pensate for high infant mortality) and a high death rate Birth rate Total population Stages of Demographic Transition Demographic Trap – resources used up to support population boom (exceeds carrying capacity)

Demographic Transition Model Animations/demo_transition.html

Family Planning can slow growth Through birth spacing, birth control, health care Through birth spacing, birth control, health care Increase availability of contraception Increase availability of contraception 55% drop in TFR of developing countries 55% drop in TFR of developing countries Developing countries Developing countries Almost half pregnancies unplanned Almost half pregnancies unplanned Lack access to family planning Lack access to family planning Replacement-level fertility achievable within decades Replacement-level fertility achievable within decades By investing in family planning By investing in family planning Reducing poverty Reducing poverty Elevating the social and economic status of women Elevating the social and economic status of women

Results of Empowering Women Educated women have fewer children Educated women have fewer children Illiterate women 64% of world’s population, 70% of the poor Illiterate women 64% of world’s population, 70% of the poor When daughters considered less valuable, not sent to school When daughters considered less valuable, not sent to school Poor conditions for women leads to environmental degradation Poor conditions for women leads to environmental degradation

Slowing Population Growth in China “One Child” - Halved birth rate and drastically reduced TFR “One Child” - Halved birth rate and drastically reduced TFR Strict family planning Strict family planning Sons still preferred – gender imbalance Sons still preferred – gender imbalance Population rapidly aging Population rapidly aging Rapidly growing economy - seen improved quality of life Rapidly growing economy - seen improved quality of life Larger middle class increases resource consumption and waste Larger middle class increases resource consumption and waste Sustainable economic plan needed to avoid environmental degradation Sustainable economic plan needed to avoid environmental degradation

Slowing Population Growth in India Tried to slow population growth for five decades Tried to slow population growth for five decades Most populous country in 2015 Most populous country in 2015 Problems increase with growing population Problems increase with growing population Poverty Poverty Malnutrition Malnutrition Environmental degradation Environmental degradation Growing middle class – resource consumption Growing middle class – resource consumption

7-5 What Are the Major Population and Environmental Problems of Urban Areas? Concept 7-5 Cities can improve individual lives, but most cities are unsustainable because of high levels of resource use, waste, pollution, and poverty. Concept 7-5 Cities can improve individual lives, but most cities are unsustainable because of high levels of resource use, waste, pollution, and poverty.

Urban Living Half the world lives in urban areas Half the world lives in urban areas 80% of Americans in cities 80% of Americans in cities Urban areas continue to grow Urban areas continue to grow Natural increase Natural increase Immigration Immigration

Major Global Trends in Urban Growth Proportion of urban global population growing Proportion of urban global population growing Number and sizes of urban areas mushrooming Number and sizes of urban areas mushrooming Rapid increase in urban populations in developing countries Rapid increase in urban populations in developing countries Urban growth slower in developed nations Urban growth slower in developed nations Poverty increasing Poverty increasing

Urban Areas and Megacities

Urbanization in the U.S. 1800–2007, increased population 5–80% in urban areas 1800–2007, increased population 5–80% in urban areas Migration patterns Migration patterns Better working and housing conditions compared to the past Better working and housing conditions compared to the past Problems in urban areas (go over later) Problems in urban areas (go over later)

Major Urban Centers in the United States

SF Bay Region Growth Animations/sf_sprawl.html

Advantages of Urbanization Economic development Economic development Innovation Innovation Education and jobs Education and jobs Technological advances Technological advances Recycling more economically feasible Recycling more economically feasible Longer life spans Longer life spans

Disadvantages of Urbanization Unsustainable systems Unsustainable systems Occupies 2%, consumes 75% Occupies 2%, consumes 75% Lack of vegetation (contributes to air pollution) Lack of vegetation (contributes to air pollution) Water problems Water problems Pollution and health problems Pollution and health problems Noise pollution Noise pollution Climate and artificial light Climate and artificial light Urban heat islands Urban heat islands Light pollution Light pollution

Urban Areas Are Rarely Sustainable

Noise Levels

Urban Sprawl Gobbling up countryside Gobbling up countryside Causes Causes Prosperity Prosperity Ample and affordable land Ample and affordable land Automobiles Automobiles Cheap gasoline Cheap gasoline Poor urban planning Poor urban planning

Fig. 7-15, p. 139 Stepped Art Urban Sprawl Around Las Vegas

Consequences of Urban Sprawl Inadequate mass transportation Inadequate mass transportation Need to drive everywhere Need to drive everywhere Decreased energy efficiency Decreased energy efficiency Traffic congestion Traffic congestion Destruction of prime cropland, forests, wetlands Destruction of prime cropland, forests, wetlands

U.S. Megalopolis: Bowash Fig. 7-17, p. 140

Urban Poor in Developing Countries Slums Slums Shantytowns and squatter settlements Shantytowns and squatter settlements Lack of basic services Lack of basic services

Living in a Shantytown Fig. 7-20, p. 143

Case Study: Mexico City Large population Large population Severe noise, water, and air pollution Severe noise, water, and air pollution 50% unemployment 50% unemployment >33% live in barrios >33% live in barrios 100,000 premature deaths per year 100,000 premature deaths per year 3 million without sewer 3 million without sewer Fecal snow Fecal snow Progress – tree planting and lower air pollution Progress – tree planting and lower air pollution Geography contributes to air pollution Geography contributes to air pollution

Thermal Inversion and Smog Animations/thermal_inversion.html

7-6 How Does Transportation Affect Urban Development? Concept 7-6 A combination of plentiful land, inexpensive fuel, and an expanding network of highways results in dispersed cities that depend on motor vehicles for most transportation. Concept 7-6 A combination of plentiful land, inexpensive fuel, and an expanding network of highways results in dispersed cities that depend on motor vehicles for most transportation.

Cities Can Grow Outward or Upward Compact cities Compact cities Transportation by walking, biking, or mass transit Transportation by walking, biking, or mass transit Hong Kong, Tokyo Hong Kong, Tokyo Dispersed cities Dispersed cities Transportation by automobile Transportation by automobile Most American cities Most American cities

Formation of Photochemical Smog Animations/photochemical_anim.html

Automobiles in the United States <10% of world’s population own 1/3 of cars <10% of world’s population own 1/3 of cars Gas guzzlers Gas guzzlers 40,000 people per year die from auto accidents 40,000 people per year die from auto accidents Largest source of air pollution Largest source of air pollution Lead to urban sprawl and congestion Lead to urban sprawl and congestion

Reduce Automobile Use HOW HOW User-pays system User-pays system Full-cost pricing Full-cost pricing Tax revenues to finance mass transit, bike paths, sidewalks Tax revenues to finance mass transit, bike paths, sidewalks High gasoline tax unlikely High gasoline tax unlikely Need to discourage automobile use Need to discourage automobile use

Alternatives to Cars Bicycles Bicycles Mass transit systems in urban areas Mass transit systems in urban areas Bus systems Bus systems Rapid rail Rapid rail

Trade-offs: Bicycles Fig. 7-21, p. 145

Trade-offs: Mass Transit Rail Fig. 7-22, p. 145

Trade-offs: Buses Fig. 7-23, p. 146

Trade-offs: Rapid Rail Fig. 7-24, p. 146

7-7 How Can Cities Become More Sustainable and Livable? Concept 7-7 An ecocity allows people to: choose walking, biking, or mass transit for most transportation needs; recycle or reuse most of their waste; grow much of their food; and protect biodiversity by preserving surrounding land. Concept 7-7 An ecocity allows people to: choose walking, biking, or mass transit for most transportation needs; recycle or reuse most of their waste; grow much of their food; and protect biodiversity by preserving surrounding land.

Environmentally Sustainable Cities Smart growth Smart growth Ecocities Ecocities Build and design people-oriented cities Build and design people-oriented cities Use energy and matter efficiently Use energy and matter efficiently Prevent pollution and reduce waste Prevent pollution and reduce waste Recycle, reuse, and compost Recycle, reuse, and compost Protect and encourage biodiversity Protect and encourage biodiversity

Smart Growth and New Urbanism