Case study: China

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Case study Chinas one-child policy
1980
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Human population growth 7 billion
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The human population is still growing rapidly
1350
Agricultural Revolution
Industrial Revolution
Hunter/ Gatherer
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Human population growth 7 billion
A few milestones that lead to our present
population

• 10,000 bc agriculture
• 1500 new crops from Americas reach Europe
• 1798 vaccinations
• 1850 sewers were separated from drinking water,
  which was filtered and chlorinated
• 1884 contraception
• 1930 better nutrition, sanitation, health care
• 1960 Green Revolution

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Result of Large Populations
pollution
Greater need for resources
starvation
Reduction in biodiversity
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World population has risen sharply
baby boom

• Global human population was lt1 billion in 1800.
• Population has doubled just since 1963.
• We add 2.5 people every second (79 million/year).

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United States birth rate (births per 1000
population)
Baby boom 1946-1964
1939-1945 WWII
1909 1919 1929 1939
1949 1959 1969 1979
1989 1999 2009
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Rates of growth vary from region to region

• At todays 1.2 global growth rate, the
  population will double in 58 years

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Global Variation in Fertility Rate
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Is population growth really a problem?

• Population growth results from technology,
  medical care, sanitation, and food.
• Death rates drop, but not birth rates.
• Some people say growth is no problem.
• New resources will replace depleted ones.
• But some resources (i.e., biodiversity) are
  irreplaceable.
• Quality of life will suffer with unchecked
  growth.
• Less food, space, wealth per person

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Population and the Environment

• Population growth can lead to environmental
  degradation.

Overpopulation in Africas Sahel region has led
to overgrazing of semi-arid lands.
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Affluence and the environment

• Poverty can lead to environmental degradation
• BUT
• wealth and resource consumption can produce even
  more severe and far-reaching environmental
  impacts.

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Population vs. Energy Use
Population (Billions), 1999 Energy Use/ Year (1999)
Developed 1.2 7.4 kW
Developing 4.6 1 kW
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Increasing our carrying capacity
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Demography studies human populations

• Demography the application of population ecology
  to the study of human populations
• Population size
• Density and distribution
• Age structure, sex ratio
• Birth, death, immigration, and emigration rates

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Population size and density
Predictions of population size depend on
different assumptions about fertility rates.
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Population density and distribution
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Population size National populations
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Age Pyramid United States 2012
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Age structure Age pyramids
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Age structure Graying populations

• Demographers project that Chinas population will
  become older over the next two decades.

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Age structure Graying populations

• Chinas aging population will mean fewer
  working-age citizens to finance social services
  for retirees.

Figure 7.11c
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Chinas natural rate of change has fallen
Chinas rate has fallen with fertility rates. It
now takes the population 4 times as long to
double as it did 25 years ago.
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Age structure Baby booms

• The United States baby boom is evident in age
  bracket 4050. U.S. age structure will change as
  baby boomers grow older.

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Sex ratios

• 100 females born to 106 males
• China 100 females born to 117 males

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Population growth depends on various factors

• Birth ?
• Death ?
• Immigration ?
• Emigration ?
• Technological advances led to dramatic decline in
  human death rates.
• Widening the gap between birth rates and death
  rates resulting in population expansion

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Migration can have environmental effects

• Immigration and emigration play large roles today.

Refugees from the 1994 Rwandan genocide endured
great hardship, and deforested large areas near
refugee camps.
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Factors affecting total fertility rate

• Urbanization decreases TFR.
• Access to medical care
• Children attend school and impose economic costs
• With social security, elderly parents need fewer
  children to support them.
• Greater education allows women to enter the labor
  force, with less emphasis on child rearing.

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Worldwide, total fertility varies widely
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Family planning and TFR

• Family planning, health care, and reproductive
  education can lower TFRs.

A counselor advises African women on health care
and reproductive rights.
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Poverty and population growth are correlated
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Wealth also produces environmental impacts

• The population problem does not exist only within
  poor countries.
• Affluent societies have enormous resource
  consumption and waste production.
• People use resources from other areas, as well as
  from their own.
• Individuals ecological footprints are huge.

One American has as much environmental impact as
6 Chinese or 12 Indians or Ethiopians.
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The Earth cant support our consuming lifestyle
Humanitys global ecological footprint surpassed
Earths capacity to support us in 1987.
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The wealth gap and population growth cause
conflict
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Wealthy nations must help others

• overcome their increasing social, economic, and
  environmental problems
• And if not
• A profoundly negative outcome for humans and the
  environment

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Longevity

• Lowest Africa (55 years) and developing Oceania
  (64) years)