Environmental Problems_ Their Causes_ and Sustainability

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					Unit 1
Fall 2008
Environmental Problems,
   Their Causes, and
              Chapter 1
“What’s the use of a house if you don’t
have a decent planet to put it on?”
     -Henry David Thoreau
    Introduction to Environment,
    Ecology, and Environmental
    Environment: external
  conditions that affect
  living organisms
• Ecology: study of
  relationships between
  living organisms and their
• Environmental Science:
  interdisciplinary study
  that examines the role of
  humans on the earth
 Solar Capital and Earth Capital
• Solar Capital: energy from the sun
  - provides 99% of the energy used on earth

• Earth Capital: life-support and economic

  -Environment describes: planet’s air, water, soil,
  wildlife, minerals, natural purification, recycling
  and pest control
             Carrying Capacity
• The maximum numbers of
  organisms of a local, regional,
  or global environment can
  support over a specified period

• Varies with:
  -time (short term seasonal
  changes and long-term global
  changes in factors such as
  -types of technology

• The ability of a
  specified system to
  survive and function
  over time
  Sustainable resource harvest
• Certain quantity of
  that resource can be
  harvested each year
  over a specified
• Sustainable supply of
  fish or timber
           Sustainable earth
• Earth’s supplies of
  resources and the
  processes that make
  up earth capital are
  used and maintained
  over a specified
            Sustainable society
• Manages its economy
  and population size
  without exceeding all or
  part of the planet’s ability
  -absorb environmental
  -replenish its resources
  -sustain human and other
  forms of life over a
  specified period (100s-
  1000s of years)
             Linear Growth
• Quantity increases by
  a constant amount       120
  per unit of time        100

• 1,2,3,4,5               80

• 1,3,5,7,9               60

• When plotted on a       20
  graph, growth of         0
  money yields a                1st Qtr   2nd Qtr   3rd Qtr   4th Qtr

  straight line sloping
       Exponential Growth
• Starts off slowly, doubles a few
  times, then grows to enormous
• Quantity increases by a fixed
  percentage of the whole in a
  given time as each increase is
  applied to the base for further
• If plotted on a graph, the
  growth yields a J shape curve
• Used to describe the
  population problem, which
  disturbs the environment today
                 Rule of 70
• How long does it take to double resource use,
  population size, or money in a savings account
  that is growing exponentially?

• Use Rule of 70 to calculate this doubling time

• Doubling time is the approximate number of
  years required to double a population
     How to calculate rule of 70
• Doubling time = 70 / % annual growth rate
• Annual growth rate = 70 / number of years to
                      double population

• For example, at a 10% annual growth rate,
  doubling time is 70 / 10 = 7 years.

• Similarly, to get the annual growth rate, divide 70
  by the doubling time. For example, 70 / 14 years
  doubling time = 5, or a 5% annual growth rate.
Growth Rate      Doubling Time
  (% per Year)     in Years
        0.1               700
        0.5               140
         1                70
         2                35
         3                23
         4                18
         5                14
         6                12
         7                10
         10                7
Does doubling time affect
     Sustainable Development
• Assumes that we have a
  right to use the earth’s
  resources and earth
  capital to meet our needs
  but that we have an
  obligation to pass on the
  earth’s resources and
  services to future
  generations in as good or
  better shape than these
  condition were passed on
  to us.
• Intergenerational equity
  or fairness
         Developed Countries
•   Average GNP is about $4,000
•   20% of the earth’s total population
•   85% of the world’s total wealth
•   75% of pollution and wastes
•   88% of the natural resources
•   USA, Japan, Germany account for more
    than 1/2 of the world’s economic output
• Diversified workforce

• Low fertility rates

• Low illiteracy rates

• Low infant mortality

• Higher average lifespan

• Greater social support systems
         Developing Countries
•   Low GNPs
•   mostly Africa, Asia, Latin America
•   80% of total population (4.7 billion)
•   15% wealth and income
•   12% natural resources
• Low diversity in workforce

• High fertility rates

• High illiteracy rates

• High infant mortality

• low average lifespan

• low social support systems
• 1 in 5 live in luxury
• 3 in 5 have enough to get by
• 1 in 5 struggles to get by on less than $1 a
• 1 in 6 are malnourished
• 1 in 3 lack enough fuel to keep warm and
       Types of Resources
Renewable               Non-      Potentially
                        renewable renewable
Direct solar energy     Fossil fuels      Fresh air
Winds, tides, flowing   Metallic          Fresh water
water                   minerals (iron,
                        Nonmetallic       Fertile soil
                        minerals (clay,
                                          Plants and
 The Tragedy of the Commons
• Common property resources: available to
  all users free of charge

• #1 cause of environmental degradation

• The cumulative effects of many people
  trying to exploit a common property
  eventually exhausts it
     Nonrenewable (Exhaustible)
• Resources that exist in a fixed quantity
• energy resources (coal, gas, petroleum)
• metallic mineral resources (iron, copper,
• nonmetallic mineral resources (salt, clay,
  sand, phosphates)
   How to preserve non-renewable

Recycling: involves collecting and reprocessing a
 resource into new products.

Reuse: using a resource over and over in the
 same form.
Model of Environmental Impact
• Number of People x Number of units of
  resources used per person x
  Environmental degradation and pollution
  per unit of resource used = Environmental
  impact of population

• PxAxT=I

• People x affluence x technology = impact
 What is your impact on Earth?

• How many earth’s are needed to maintain
  the world’s current population to your
  standard of living?
Environmental Degradation
    Environmental Degradation
• Common property
  resources: owned by
  no one but are
  available to all users
  free of charge
• Tragedy of the
• Can convert potentially
  renewable resources
  into nonrenewable
•   Four Rs of resource:
•   Refuse (don’t use)
•   Reduce
•   Reuse
•   Recycle
• input pollution control:
  throughput solution.
• Slows or eliminates
  the production of
  pollutants, often by
  switching to less
  harmful chemicals or
• Pollution cleanup/
  output pollution
• cleanup: involves
  cleaning up pollutants
  after they have been
    Environmental Worldviews
• How people think the
  world works, what
  they think their role in
  the world should be,
  and what they see as
  right and wrong
  (environmental ethics)
          Planetary management
• Has become increasingly
  common during the past 50
• We are the planet’s most
  important species, and we are
  in charge of the rest of nature
• There is always more
• All economic growth is good.
  Potential for economic growth
  is limitless
• Our success depends on how
  well we manage earth’s
  system for our benefit
       Earth-wisdom worldview
• Nature exists for all of the
  earth’s species, not just
  for us
• There is not always more
• Not all forms of economic
  growth is beneficial to the
• Our success depends on
  learning to cooperate with
  one another and with the
        Working with the Earth
• Earth wisdom: learning
  as much as we can about
  how the earth sustains
  itself and adapt to ever-
  changing environmental
  conditions and integrating
  such lessons from nature
  into the ways we think
  and act