Human Population

Chapter 8Environmental Science

The Central Case

• China’s One-Child Policy

• How does the human population affect the environment?

Section 1

• Objectives

• 1. Describe how technological advances have contributed to human population growth

• 2. Explain recent trends in population growth

• 3. Identify characteristics of human population that are studied by demographics

Section 1

• Human population has undergone tremendous growth that dwarfs all previous growth during our 200,000 years of existence.

• The world population hit 1 billion about 1800, but now is about 6.8 billion as of 2010.

• What is the largest population that Earth can sustain???.....

Section 1

• Agricultural Revolution• Around __________________ years ago

human societies changed from ___________________ to _____________________.

• Results:• 1. • 2• 3• 4

Section 1

• Industrial Revolution

• Began in _________________

• Shift from _____________ life to ___________ life.

• Led to these improvements:• 1.• 2• 3

Section 1

• Sanitation

• Louis Pasteur:

• Things we learned:• 1. • 2.• 3.• 4.

Section 1

• Medical Technology

• Things we learned:

• 1.

• 2.

Section 1

• Changes in Agriculture

• Things that changed:• 1.• 2.• 3.

• Real Data lab

Section 1

• Recent Trends in Human Population Growth

• ________________ is the number of babies out of 1000 that die during their first year of life.

• _________________ is the average number of years an individual is expected to live.

Section 1

• ______________ is how the population changes in size during a specific period of time.

• Since the 1960’s the population rate has slowed from 2.1% to 1.2%

• Rule of 72: divide 72 by the growth rate to determine how quickly a population will double.

Section 1

• Figure 4

• Growth rate varies by region – in fact some populations are actually decreasing.• Ex: Germany and Russia

Section 1

• Demography

• The study of human population statistics is called __________________.

• They use the same terminology we used earlier:• 1.• 2.• 3.

Section 1

• Population size

• Changes every second

• Population density• Global densities

• Population densities are highest in regions with _____________________.

• Population densities are lowest in regions with _____________________.

Section 1

• Population densities• _______________ are more densely

populated than regions ___________________

• Regional densities• ___________________ are more densely

populated than __________________ areas.

• Population distribution• Human population is ____________ rather

than _______________ or ___________________.

Section 2

• Objectives

• 1. Describe total fertility rates and replacement fertility

• 2. Explain how the age structure and sex ratio of a population define its potential for growth

• 3. Describe the demographic transition

• 4. Discuss social factors that affect population growth

Section 2

• Predicting population growth

• Some scientists predict the world’s population may reach 9 billion by 2050……others project it could reach 10.5 billion by then.

• That is a big range……..so how do demographers make theses predictions?????

Section 2

• Scientists use the same statistics ecologists use to describe ecological populations:• 1

1234

• 2

Section 2

• Fertility rate

• _______________ refers to the number of children a female member of a population has during her lifetime.• In the past the total fertility rate has been

___.• Recently it has _______ in many regions of the

world

• The total fertility rate for a nation that would keep its population size stable: ____________

Section 2

• Age Structure and Sex Ratios

• Figure 9

• Quick Lab

Section 2

• The Demographic Transition

• The shift from high birth rates and death rates to low birth rates and death rates

• This is a 4-stage process• 1• 2• 3• 4

Section 2

• Pre-industrial Stage• both death rates and birth rates are _______

• Why??

• These populations are not likely to see much ________________.

• The Transitional Stage• Led by _________________• Birth rates are ______, death rates

___________• Population ____________

Section 2

• The Industrial Stage• Increases ___________ outside the home,

especially for ______________.• ____________children are born.• Birthrates ______________• Population growth ___________

Section 2

• The Post-Industrial Stage• Both birthrates and deathrates ____• The population __________

Section 2

• Social Factors

• What social factors affect a nation’s population growth????

• List them…..

Section 2

• These factors also affect a country’s population growth:• 1.• 2.• 3.

Section 2

• Developing Nations• Definition:• Tend to have higher ____________,

___________________, and _______________.• Life expectancy is ______________.• Reasons: ___________, ______________,

________________, _______________.• But, population growth of these nations

_________ that of developed nations.

Section 2

• Developing countries• National policies:

• 1. • 2• 3• 4

• Empowering women

Section 2

• Developed nations

• Developed countries tend to have lower population growth, but they tend to have MUCH higher resource consumption.

• 1 American can have as much environmental impact as 5 Chinese or 13 Pakistanis.

• So, who is the bigger threat to the environment??????

Section 3

• Objectives

• 1. Describe how humans impact their environments

• 2. Discuss the negative and positive impacts of technology.

Section 3

• Impacts of population

• Affluent societies• Tend to use more

• 1• 2• 3• 4

• Affluent countries tend to have higher _______________________.

Section 3

• Poor Societies• Put different stresses on their

environment• Overwhelmed governments• Land overuse• Land clearing

Section 3

• The Wealth Gap

• The difference between affluent countries and poor countries.• Leads to different social and

environmental stress• Refers to the difference in assets and

income between individuals or nations.• Figure 16

Section 3

• Quality of life

• What determines quality of life?

Section 3

• Impacts of technology

• Negative impacts• 1.• 2• 3• 4

Section 3

• Impacts of technology

• Positive impacts• 1• 2• 3