Chapter 1- Science and the
Environment
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I. Understanding Our Environment
A. What is Environmental Science?
1. The study of the impact of humans on
the environment.
2. One goal is to understand and solve
environmental problems.
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3. Scientists study two main types of
interactions between humans and the
environment.
4. Water and plants
5. How our actions alter our environment.
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6. Ecology is the study of how living things
interact with each other and with their
nonliving environment.
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7. See page 7 in your textbook to see the
other major fields that contribute to
Environmental science.
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B. Scientists as Citizens, Citizens as
Scientists
1. Everyone can take an active role in
our environment
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C. Our Environment Through Time
1. For most of human history people
were known as hunter-gatherers, people
who obtain food by collecting plants and
animals.
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2. Hunter gatherers affected their
environment in many ways.
3. Tribes set fires to burn the prairies so
they could hunt bison.
4. Over hunting may have led to the
disappearance of some species.
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5. Eventually many hunter-gatherer groups
began to use the land as agriculture.
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B. The agricultural Revolution
1. Agriculture is the practice of growing,
breeding and caring for plants an
animals than are used for food, clothing,
housing, transportation and other
purposes.
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2. Agricultural revolution allowed human
populations to grow very fast.
3. An area of land can support up to 500
times as many people by farming as it
can by hunting and gathering.
4. The revolution also changed the food we
eat.
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5. Replacing forests and wetlands with
farmland, habitats were destroyed.
6. It caused soil loss, floods, and water
shortages.
7. The soil became overworked and it
became infertile.
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C. The Industrial Revolution
1. A shift from energy sources like animals
to coal and oil.
2. Machinery reduced the amount of land
and human labor needed for farming.
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C. Improving Quality of Life
1. The industrial revolution introduced
many positive changes.
2. Examples: light bulbs, sanitation,
nutrition, medical care, telephone,
computer.
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3. In the 1900’s modern societies began to
use artificial substances in place of raw
animal or plant products.
4. Plastics and other artificial materials
made life easier.
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D. Spaceship Earth
1. Earth is considered a closed system-the
only thing that enters is energy from the
sun and the only thing that leaves is heat.
2. There are some problems with this type
of system.
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3. Resources are limited.
4. Waste will be produced more quickly than
we can dispose.
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E. Population Growth: A local Pressure
1. The agricultural and Industrial
revolution has allowed the human
population to grow much faster than
before.
2. Technology, medicine and sanitation
increase the human population.
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3. The size of the human population in 2000
was more than 10 times larger than I was
400 years ago.
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F. What are our main environmental
Problems?
1. Resource depletion
2. Any natural material that is used by
humans is called a natural resource.
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3. Natural resource can be renewable or
nonrenewable resource.
4. A renewable resource is a resource that
can be replaced quickly by natural
processes.
5. Examples: fresh water, air, soil, trees and
crops.
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6. A nonrenewable resource is a resource
that forms at a slower rate than it is
consumed.
7. The most common nonrenewable
resources are minerals and fossil fuels.
8. Once they are used up, it might take
MILLIONS of years to replenish it!
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9. Resources are said to be depleted when
a large fraction of the resource has been
used up.
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G. Pollution
1. Pollution is an undesired change in
air, water or soil that adversely affects
health, survival, or activities of humans
or other organisms.
2. There are two types of pollution:
biodegradable and nondegradable.
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3. Biodegradable pollutants are pollutants
that can be broken down by natural
processes: human sewage or food wastes.
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4.Nondegradable pollutants cannot be
broken down: mercury, lead, and some
plastics.
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H. Loss of Biodiversity
1. Biodiversity refers to the number and
variety of species that live in an area.
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II. The Environment and Society
A. The Tragedy of the Commons
1. Hardin stated that the conflict
between solving environmental issues is
the conflict between short-term interests
of individuals and the long-term welfare
of society.
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2. His essay basically said that someone or
some group has to take responsibility for
maintaining a resource. If no one does,
the resource can be overused and
become depleted.
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OVER GRAZING
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B. Economics and the Environment
1. One basic rule of economics is the
law of supply or demand.
2. The greater the demand for a limited
supply of something, the more the thing
is worth.
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3. The cost of environmental solutions can
be high.
4. A cost-benefit analysis balances the cost
of the action against the benefits on
expects from it.
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5. Risk assessment, is a tool that helps to
create cost-effective ways to protect our
health and the environment.
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C. Developed and developing countries
1. Developed countries have a higher
average incomes, slower population
growth, diverse industrial economies,
and stronger social support systems.
2. United States, Canada, Japan and
countries of Western Europe.
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3. Developing countries- have lower average
incomes, simple agriculture-based
economies, and rapid population growth.
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D. Population and Consumption
1. Most environmental problems can be
traced back to two root causes: Human
population growing too quickly, people
are using up, wasting or polluting natural
resources.
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2. An ecological footprint shows the
productive area of Earth needed to
support one person in a particular country.
3. Environmental problems are complex and
simple solutions are rare.
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4. Sustainability is the condition in which
human needs are met in such a way that a
human population can survive indefinitely.
5. A sustainable world is not an unchanging
world.
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THE END
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