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13e. ENVIRONMENTAL SCIENCE. CHAPTER 6: The Human Population and Urbanization. Global Population. http://www.youtube.com/watch?v=sc4HxPxNrZ0. Core Case Study: Are There Too Many of Us? (1). 6.8 billion people 83 million more each year 2050: 9.5 billion people at current growth rates

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Environmental science

13e

ENVIRONMENTALSCIENCE

CHAPTER 6:The Human Population and Urbanization


Global population
Global Population

  • http://www.youtube.com/watch?v=sc4HxPxNrZ0


Core case study are there too many of us 1
Core Case Study: Are There Too Many of Us? (1)

  • 6.8 billion people

  • 83 million more each year

  • 2050: 9.5 billion people at current growth rates

  • Most growth in low-income and middle-income countries

  • Enough resources for growing population?


A important question
A important question

  • Can we provide an adequate standard of living for a projected 2.7 billion more people by 2050 without causing widespread environmental damage?

  • Overpopulation vs overconsumption


Core case study are there too many of us 2
Core Case Study: Are There Too Many of Us? (2)

  • Negative viewpoint

    • 20% currently lack basic necessities

    • Declining conditions increase death rate

    • Increased resource use

    • Increased environmental degradation

  • Positive viewpoint

    • Technological solutions will increase carrying capacity

    • Growing population a valuable resource


Environmental science

Crowded street in China: largest population of all countries with 1.3 Billion people

Together China and India are home to 1 of every 3 people on Earth

Fig. 6-1, p. 94


6 1 how many people can the earth support
6-1 How Many People Can the Earth Support? with 1.3 Billion people

  • Concept 6-1 We do not know how long we can continue increasing the earth’s carrying capacity for humans without seriously degrading the life-support system that keeps us and many other species alive.


Human population explosion
Human Population Explosion with 1.3 Billion people

  • Exponential growth (J-curve) in past 200 years

  • Three major reasons

    • Ability to expand into diverse habitats

    • Emergence of agriculture

    • Sanitation systems and control of infectious diseases decreased death rates


How long can the human population grow
How Long Can the Human with 1.3 Billion peoplePopulation Grow?

  • Rate slowing, but still exponential

  • Uneven global growth

  • No population can grow indefinitely

  • 2050: 9.5 billion people at current growth rates

  • Most growth in developing countries, least likely to cope


Environmental science

13 with 1.3 Billion people

12

11

10

9

8

7

6

5

4

3

2

1

0

Exponential Growth: the J-shaped curve of past world population growth

?

Industrial revolution

Black Death—the Plague

2-5 million

years

8000

6000

4000

2000

2000

2100

B.C.

A.D.

Hunting

and gathering

Agricultural revolution

Industrial revolution

Fig. 1-1, p. 1

Fig. 1-10, p. 16


Environmental science

UN world population projections with 1.3 Billion people

12

High

10.8

11

10

Medium

9.5

9

8

Population (billions)

7

Low

7.8

6

5

4

3

2

1950

1960

1970

1980

1990

2000

2010

2020

2030

2040

2050

Year

Fig. 6-2, p. 96


Environmental science

Natural Capital Degradation with 1.3 Billion people

Altering Nature to Meet Our Needs

Reduction of biodiversity

Increasing use of the earth's net primary productivity

Increasing genetic resistance of pest species and disease-causing bacteria

Elimination of many natural predators

Introduction of potentially harmful species into communities

Using some renewable resources faster than they can be replenished

Interfering with the earth's chemical cycling and energy flow processes

Relying mostly on polluting and climate-changing fossil fuels

Fig. 6-3, p. 97


6 2 what factors influence the size of the human population
6-2 What Factors Influence the Size of the Human Population? with 1.3 Billion people

  • Concept 6-2A Population size increases through births and immigrationand decreases through deaths and emigration.

  • Concept 6-2BThe average number of children born to women in a population (total fertility rate) is the key factor that determines the population size.


Population change
Population Change with 1.3 Billion people

Population change =

(births + immigration) - (deaths + emigration)

Demographers look at birth rates and death rates

  • 2009:

    China, 1.3 billion people

    India, 1.1 billion people

    USA, 306 million people


Number of children
Number of Children with 1.3 Billion people

  • Fertility rates affect population size and growth rate

  • Total fertility rate (TFR)

  • 1950-2009: Global TFR fell to:

    1.6 from 2.5 in developed countries

    2.8 from 6.5 in developing countries


Case study the u s population is growing rapidly
Case Study: The U.S. Population Is Growing Rapidly with 1.3 Billion people

  • Quadrupled in 100 years, despite oscillations in TFR

  • Baby boom: High TFR

  • Current births outnumbering deaths and legal immigration

  • Growing faster than other developed countries

  • 2050 estimate: 439 million


Environmental science

TFR for US with 1.3 Billion people

4.0

3.5

3.0

2.5

2.1

Births per woman

2.0

1.5

Baby boom

(1946–64)

Replacement

level

1.0

0.5

0

1920

1930

1940

1950

1960

1970

1980

1990

2000

2010

Year

Fig. 6-4, p. 98


Factors affecting birth rates 1
Factors Affecting Birth Rates (1) with 1.3 Billion people

  • Importance of children as part of labor force

  • Cost of raising and educating children

  • Availability of retirement systems

  • Urbanization

  • Educational and employment opportunities for women


Factors affecting birth rates 2
Factors Affecting Birth Rates (2) with 1.3 Billion people

  • Average marriage age

  • Availability of legal abortion and reliable birth control methods

  • Religious beliefs, traditions, cultural norms


Factors affecting death rates
Factors Affecting Death Rates with 1.3 Billion people

  • Population growth is also response to decline in crude death rate

  • Life expectancy and infant mortality rateimportant indicators of overall health

  • Average life expectancy increased

  • Infant mortality – barometer of a society’s quality of life


Environmental science

Supplement 3, Fig. 8, p. S10 with 1.3 Billion people


6 3 how does a population s age structure affect its growth or decline
*6-3 How Does a Population’s with 1.3 Billion peopleAge Structure Affect Its Growth or Decline?

  • Concept 6-3The numbers of males and females in young, middle, and older age groups determine how fast populations grow or decline.


Age structure
*Age Structure with 1.3 Billion people

  • Distribution of population

    • Prereproductive

    • Reproductive

    • Postreproductive

  • Country with many young people grows rapidly

  • Country with many older people will decline

  • Developing countries: >30% under 15 years old


Environmental science

Fig. 6-6, p. 102 with 1.3 Billion people


Environmental science

Fig. 6-6, p. 102 with 1.3 Billion people


Age structure predicts the future
Age Structure Predicts the Future with 1.3 Billion people

  • 36% of U.S. population baby boomers

  • Graying of America

  • Over time: increasing percentage of older baby boomers

  • Changes the economy


Environmental science

1955 with 1.3 Billion people

1985

2015

2035

Tracking the baby-boom generation in the United States. US population by

age and sex for years indicated.

Stepped Art

Fig. 6-8, p. 103


Declines occur in aging populations
Declines Occur in Aging Populations with 1.3 Billion people

  • “Baby bust” or “birth dearth” – TFR below 1.5 children per couple

  • Labor shortages

  • Strain on governments for public services

  • Fewer taxpayers


6 4 how can we slow human population growth
*6-4 How Can We Slow Human Population Growth? with 1.3 Billion people

  • Concept 6-4

    We can slow population growth by

    -reducing poverty

    -encouraging family planning

    -and elevating the status of women.


Stages of demographic transition
* with 1.3 Billion peopleStages of Demographic Transition

  • Preindustrial

  • Transitional – demographic trap

  • Industrial

  • Postindustrial

  • Some analysts believe that most of the world’s developing countries will make a demographic transition over the next few decades, mostly because modern technology can raise per capita incomes by bringing economic development and family planning to such countries. Other analysts fear rapid pop growth, extreme poverty, and increasing environmental degradation in some low-income countries could leave them stuck in stage 2.


Environmental science

Stage 1 with 1.3 Billion people

Preindustrial

Stage 2

Transitional

Stage 3

Industrial

Stage 4

Postindustrial

Population

grows very

slowly because

of a high

birth rate

(to compensate

for high infant

mortality) and a

high death rate

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

80

70

60

50

40

30

20

10

0

Total population

Birth rate and death rate

(number per 1,000 per year)

Birth rate

Death rate

Low

Increasing

Very high

Decreasing

Low

Zero

Negative

Growth rate over time

Stepped Art

Fig. 6-10, p. 105


Think about it
Think about it with 1.3 Billion people

  • Stage 1: birth rate, death rate, population

  • Stage 2: birth rate, death rate, population

  • Stage 3: birth rate, death rate, population

  • Stage 4: birth rate, death rate, population


Family planning 1
Family Planning (1) with 1.3 Billion people

  • Birth spacing, birth control, health care

  • Increased availability of contraception

  • 55% drop in TFR of developing countries

  • Developing countries

    • Almost half pregnancies unplanned

    • Often lack access to family planning


Family planning 2
Family Planning (2) with 1.3 Billion people

  • Invest in family planning

  • Reduce poverty

  • Elevate the social and economic status of women


Empowering women can slow population growth 1
Empowering Women Can Slow Population Growth (1) with 1.3 Billion people

  • Women tend to have fewer children if they:

    • are educated

    • control their own fertility

    • have a paying job outside the home

    • do not have their rights suppressed


Empowering women can slow population growth 2
* with 1.3 Billion peopleEmpowering Women Can Slow Population Growth (2)

  • Women do almost all domestic housework and childcare

  • Women do 60-80% of agriculture, wood gathering, water hauling

  • Globally, women do 2/3 of all work for 10% of income


Empowering women can slow population growth 3
Empowering Women Can Slow Population Growth (3) with 1.3 Billion people

  • Illiterate woman 64% of world’s population, 70% of the poor

  • When daughters considered less valuable, not sent to school

  • Poor conditions for women leads to environmental degradation


Case study slowing population growth in china 1
Case Study: Slowing Population Growth in China (1) with 1.3 Billion people

  • One-child families

  • Halved birth rate and drastically reduce TFR

  • Improved quality of life

  • Strict family planning

  • Sons still preferred – gender imbalance


Case study slowing population growth in china 2
Case Study: Slowing Population Growth in China (2) with 1.3 Billion people

  • Population rapidly aging

  • Rapidly growing economy

  • Larger middle class increases resource consumption and waste

  • Sustainable economic plan needed to avoid environmental degradation


Case study slowing population growth in india
Case Study: Slowing Population Growth in India with 1.3 Billion people

  • Tried to slow population growth for five decades

  • Most populous country in 2015

  • Problems increase with growing population

    • Poverty

    • Malnutrition

    • Environmental degradation

    • Growing middle class – resource consumption


Assignment
Assignment with 1.3 Billion people

  • Read Handout: “What do you think? Cultural Choices and the Rate of Population Growth” that discusses the approach to population control taken by two Indian states, Kerala and Andra Pradesh

  • Answer the question Which method of population control (that used by Kerala or Andra Pradesh) offers better insights and models for other countries? What are the benefits and limitations of each approach?

  • What do you think of the approach taken in Thailand? Why might this approach not work everywhere?


6 5 what are the major urban resource environmental problems
6-5 What Are the Major Urban Resource Environmental Problems?

  • Concept 6-5Most cities are unsustainable because of high levels of resource use, waste, pollution, and poverty.


Urban living
Urban Living Problems?

  • Half the world lives in urban areas

  • 79% of Americans live in cities

  • 50% of world population lives in cities

  • Urban areas continue to grow

    • Natural increase

    • Immigration


Major trends in urban growth
Major Trends in Urban Growth Problems?

  • Proportion of urban global population growing

  • Number and sizes of urban areas mushrooming

  • Rapid increase in urban populations in developing countries

  • Urban growth slower in developed nations

  • Poverty increasing


Environmental science

Shows populations of Problems?18 megacities (each with 10 million or

more people) in 2009 and their projected populations in 2015. All but 3

are located in developing countries.

Karachi

10.4 million

16.2 million

Dhaka

13.2 million

22.8 million

Beijing

10.8 million

11.7 million

Tokyo

26.5 million

27.2 million

New York

16.8 million

17.9 million

Cairo

10.5 million

11.5 million

Los Angeles

13.3 million

19.0 million

Mumbai

(Bombay)

16.5 million

22.6 million

Osaka

11.0 million

11.0 million

Calcutta

13.3 million

16.7 million

Mexico City

18.3 million

20.4 million

Sao Paulo

18.3 million

21.2 million

Manila

10.1 million

11.5 million

Lagos

12.2 million

24.4 million

Jakarta

11.4 million

17.3 million

Delhi

13.0 million

20.9 million

Shanghai

12.8 million

13.6 million

Key

Buenos Aires

12.1 million

13.2 million

2004 (estimated)

2015 (projected)

Fig. 6-11, p. 108


Case study urbanization in the united states 1
Case Study: Urbanization in the Problems?United States (1)

  • 1800–2009: urban population increased from 5% to 79%

  • Migration patterns

    • Rural areas to large cities

    • Large cities to suburbs and smaller cities

    • Cities and suburbs to rural areas

    • North and East to South and West


Environmental science

Almost 8 of every 10 Americans live in Problems?

urban areas. Areas with names in white

Are fastest growing metropolitan areas.

48% of all Americans live in cities of 1

million or more

Fig. 6-12, p. 109


Urban sprawl is a product of
Urban Sprawl is a product of Problems?

  • Prosperity

  • Ample and affordable land

  • Automobiles

  • Cheap gasoline

  • Poor urban planning

  • Urban sprawl=growth of low density development on the edges of cities and towns


Urban sprawl problems
Urban Sprawl Problems Problems?

  • Increased automobile use

  • Decreased energy efficiency

  • Destruction of cropland, forests, wetlands

  • Economic deaths of some cities


Environmental science

Natural Capital Degradation Problems?

Urban Sprawl

Land and

Biodiversity

Energy, Air,

and Climate

Water

Economic Effects

Loss of cropland

Increased use of surface

water and groundwater

Increased energy use

and waste

Decline of

downtown business

districts

Loss of forests and

grasslands

Increased runoff and

flooding

Increased air pollution

Increased

unemployment in

central city

Loss of wetlands

Increased greenhouse

gas emissions

Increased surface water

and groundwater

pollution

Loss and

fragmentation of

wildlife habitats

Can enhance climate

change

Loss of tax base in

central city

Decreased natural

sewage treatment

Fig. 6-14, p. 110


Advantages of urbanization 1
Advantages of Urbanization (1) Problems?

  • Economic development

  • Innovation

  • Education and jobs

  • Technological advances

  • Longer life spans


Advantages of urbanization 2
Advantages of Urbanization (2) Problems?

  • Better social and medical services

  • Recycling more feasible

  • Biodiversity increased

  • Increased energy efficiency


Disadvantages of urbanization 1
Disadvantages of Urbanization (1) Problems?

  • Unsustainable systems

  • Lack of vegetation

  • Water problems

  • Pollution and health problems


Disadvantages of urbanization 2
Disadvantages of Urbanization (2) Problems?

  • Noise pollution

  • Climate and artificial light

  • Urban heat islands

  • Light pollution


Environmental science

Natural capital degradation Problems?: urban areas rarely are sustainable systems. Typical city

Depends on large non-urban areas for huge inputs of matter and energy resources

and for large outputs of waste matter and heat.

Inputs

Outputs

Energy

Solid wastes

Waste heat

Food

Air pollutants

Water

Water pollutants

Raw

materials

Greenhouse gases

Manufactured

goods

Manufactured goods

Noise

Money

Wealth

Information

Ideas

Fig. 6-15, p. 111


Urban poor in developing countries
Urban Poor in Developing Countries Problems?

  • Slums

  • Shantytowns and squatter settlements

  • Lack of basic services



Case study mexico city 1
Case Study: Mexico City (1) Problems?

  • Large population

  • Severe noise, water, and air pollution

  • 50% unemployment

  • 100,000 premature deaths per year


Case study mexico city 2
Case Study: Mexico City (2) Problems?

  • 3 million without sewer

  • Fecal snow

  • Geography contributes to air pollution

  • Progress – tree planting and lower air pollution


6 6 how does transportation affect urban environmental impacts
6-6 How Does Transportation Affect Urban Environmental Impacts?

  • Concept 6-6 In some countries, most people live in dispersed urban areas and depend mostly on motor vehicles for their transportation.


Cities can grow outward or upward
Cities Can Grow Outward or Upward Impacts?

  • Compact cities

    • Transportation by walking, biking, or mass transit

    • Hong Kong, Tokyo

  • Dispersed cities

    • Transportation by automobile

    • Most American cities


Automobiles
Automobiles Impacts?

  • Gas guzzlers

  • 40,000 people per year die from auto accidents in the United States

  • World’s largest source of air pollution

  • Lead to urban sprawl and congestion


Reduce automobile use
Reduce Automobile Use Impacts?

  • User-pays system

  • Full-cost pricing

  • Tax revenues to finance mass transit, bike paths, sidewalks

  • High gasoline tax unlikely

  • Need to discourage automobile use


Alternatives to cars
Alternatives to Cars Impacts?

  • Bicycles

  • Mass transit systems in urban areas

  • Bus systems

  • Rapid rail


Environmental science

Trade-Offs Impacts?

Bicycles

Advantages

Disadvantages

Are quiet and

non-polluting

Provide little

protection in an

accident

Take few

resources to

make

Provide no protection

from bad weather

Burn no fossil

fuels

Are impractical for

long trips

Require little

parking space

Secure bike parking

not yet widespread

Fig. 6-18, p. 115


Environmental science

Trade-Offs Impacts?

Mass Transit Rail

Advantages

Disadvantages

Uses less energy

and produces less

air pollution than

cars do

Is expensive to build

and maintain

Is cost-effective only

in densely populated

areas

Reduced need for

more roads and

parking areas

Commits riders to

transportation

schedules

Causes fewer

injuries and

deaths than

cars do

Reduces car

congestion in

cities

Can cause noise and

vibration for nearby

residents

Fig. 6-19, p. 116


Environmental science

Trade-Offs Impacts?

Buses

Advantages

Disadvantages

Can greatly reduce car

use and air pollution

Can lose money because

they require affordable fares

Can get caught in traffic

and add to noise and

pollution

Can be rerouted as

needed

Cost less to develop

and maintain than

heavy-rail system

Commit riders to

transportation schedules

Fig. 6-20, p. 116


Environmental science

Trade-Offs Impacts?

Rapid Rail

Advantages

Disadvantages

Is much more energy

efficient per rider than cars

and planes are

Is costly to run and

maintain

Causes noise and

vibration for nearby

residents

Produces less pollution

than do cars and planes

Can reduce need for more

air travel, cars, roads, and

parking areas

Has some risk of

collision at car

crossings

Fig. 6-21, p. 116


6 7 how can cities become more sustainable and livable
* Impacts?6-7 How Can Cities Become More Sustainable and Livable?

  • Concept 6-7An ecocityallows people to choose walking, biking, or mass transit for most transportation needs; recycle or reuse most of their wastes; grow much of their food; and protect biodiversity by preserving surrounding land.

  • What is an Ecocity? What is an example of an ecocity?


Environmentally sustainable cities
Environmentally Sustainable Cities Impacts?

  • Smart growth

  • Ecocities

    • Use renewable energy as much as possible

    • Build and design people-oriented cities

    • Use energy and matter efficiently

    • Prevent pollution and reduce waste

    • Recycle, reuse, and compost

    • Protect and encourage biodiversity

    • Promote urban gardens and farmers markets

    • Zone for environmentally stable population levels


Homework assignment
Homework Assignment Impacts?

  • Go on an ecocity scavenger hunt! Find at least 3 things in Athens or on campus that could be found in an ecocity.

  • Take pictures and email them with a description of why you think you would find it in an ecocity 

  • You may work in pairs or groups of 3 if you wish


Environmental science

Solutions Impacts?

Smart Growth Tools

Protection

Limits and Regulations

Limit building permits

Preserve existing open space

Urban growth

boundaries

Buy new open space

Buy development rights that

prohibit certain types of

development on land parcels

Greenbelts around cities

Public review of new

development

Taxes

Zoning

Tax land, not buildings

Encourage mixed use of

housing and small

businesses

Tax land on value of actual use

(such as forest and agriculture)

instead of on highest value as

developed land

Concentrate

development along mass

transportation routes

Promote high-density

cluster housing

developments

Tax Breaks

For owners agreeing not to allow certain types of development (conservation easements)

Planning

Ecological land-use

planning

For cleaning up and developing abandoned urban sites (brownfields)

Environmental impact

analysis

Revitalization and New Growth

Integrated regional

planning

Revitalize existing towns and cities

State and national

planning

Build well-planned new towns and villages within cities

Fig. 6-22, p. 117


Case study curitiba ecocity in brazil 1
*Case Study: Impacts?Curitiba, Ecocity in Brazil (1)

  • Curitiba – “ecological capital” of Brazil

  • Inexpensive, efficient mass transit

  • High-rise apartments near bus routes, mixed-use structures

  • Bike and pedestrian paths


Case study curitiba ecocity in brazil 2
Case Study: Curitiba, Ecocity in Brazil (2) Impacts?

  • 1.5 million trees planted

  • Recycling

  • Many services for the poor

  • Emphasis on ecological awareness, health, literacy


Curitiba video
Curitiba Video Impacts?

  • http://www.youtube.com/watch?v=hRD3l3rlMpo&feature=fvw


Environmental science

Bus rapid transit system in Curitiba, Brazil. Boarding is speeded up by the use of

Extra-wide doors and boarding platforms sheltered by large glass tubes where

passengers can pay before getting on the bus.

Fig. 6-23, p. 118


Environmental science

Each of the 5 major spokes has 2 express lanes used only speeded up by the use of

by buses.

City

center

Route

Direct

Workers

Interdistrict

Feeder

Express

Fig. 6-23, p. 118


Three big ideas from this chapter 1
Three Big Ideas from This Chapter - #1 speeded up by the use of

The human population is increasing rapidly and may soon bump up against environmental limits.


Three big ideas from this chapter 2
Three Big Ideas from This Chapter - #2 speeded up by the use of

We can slow human population growth by reducing poverty, encouraging family planning, and elevating the status of women.


Three big ideas from this chapter 3
Three Big Ideas from This Chapter - #3 speeded up by the use of

Most urban areas, home to half of the world’s people, are unsustainable, but they can be made more sustainable and livable within your lifetime.


Review growth curves
Review Growth Curves speeded up by the use of

Exponential Growth

Logistic Growth

Carrying capacity= capacity of a given habitat to support a given species, stated in terms of the maximum population of the species that the habitat can support over a given period



Environmental science

*What will happen here? each of the age structure diagrams?

Fig. 6-6, p. 102