Download an introduction to environmental science

AN INTRODUCTION
TO
ENVIRONMENTAL SCIENCE
Dr. B. K. Bindhani
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Assistant Professor
KIIT School of Biotechnology
KIIT University, Bhubaneswar,
Orissa, India
This lecture will help you understand:
• The
nature
of
environmental science.
• The scientific method
and
the
scientific
process.
• Natural resources and
their importance.
• Culture
worldviews.
and
• Environmental ethics.
• Sustainability.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
The “environment”
Consists of both:
Biotic factors (living things)
&
Abiotic factors (nonliving things)
that surround us and with which
we interact.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Humans and the environment
• We humans exist within the environment and
are a part of the natural world.
• Like all other species, we depend for our
survival on a properly functioning planet.
• Thus, our interactions with our environment
matter a great deal.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Natural resources
• Renewable resources like sunlight cannot be depleted.
• Nonrenewable resources like oil CAN be depleted.
• Resources like timber and clean water are renewable only
if we do not overuse them.
Figure 1.1
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Global human population growth
• Our population has
skyrocketed to over
6 billion.
• The agricultural and
industrial revolutions
drove population
growth.
Figure 1.2
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Thomas Malthus (1766-1834)
Population growth will lead
to starvation, war, disease.
Death rates check
population unless birth rates
are lowered.
In our day, Paul Ehrlich
(The Population Bomb,
1968) is called
“neo-Malthusian.”
Figure 1.3
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“The tragedy of
the commons!”
Garrett Hardin, 1968:
In a “commons” open to
all, unregulated use will
deplete limited
resources.
Figure 1.4
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Environmental science
How does the natural world work?
How does our environment affect us?
How do we affect our environment?
Applied goal: Developing solutions to environmental
problems.
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What is an “environmental problem?”
Definitions differ.
The pesticide DDT:
was thought safe in
1945
is known to be toxic
today
but is used widely in
Africa to combat
malaria
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Figure 1.5
Environmental science
… can help us avoid mistakes made by past civilizations.
On Easter Island, people annihilated their culture by
destroying their environment.
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From The Science behind the Stories
Environmental science
… is an
interdisciplinary
field, drawing on
many diverse
disciplines.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Figure 1.6
Environmental science
… is NOT the same as
environmentalism.
It is science, NOT
advocacy.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Science
A systematic process for learning about the world and
testing
our
understanding
of
it
A dynamic process of observation, testing, and discovery
And the accumulated body of knowledge that results
from this process
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Applications of science
Policy decisions and
management practices
are applications of science.
Prescribed burning, used to
restore forest ecosystems
altered by human
suppression of fire.
Figure 1.8a
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Applications of science
Technology is another
application of science.
Energy-efficient
methanol-powered
fuel cell car from
DaimlerChrysler
Figure 1.8b
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Scientific method: Assumptions
Fixed natural laws govern how the universe works
All events arise from causes, and cause other events
We can use our senses and reason to detect and describe
nature’s laws
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Scientific method
A step-by-step method
for testing ideas with
observations.
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Scientific method
Scientists use educated guesses called hypotheses to
generate predictions
that are then tested experimentally.
Results may reject or fail to reject a hypothesis.
Results never confirm a hypothesis, but only lend support to
it by failing to reject it.
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Experiments
Manipulative experiments
are strongest.
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Natural or correlational
ones are often necessary.
Figure 1.10
Scientific process
Peer review,
publication,
and debate are
parts of the
larger
scientific
process.
Figue 1.11
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Hypothesis, theory, and paradigm
Hypothesis = an educated guess, to be tested
Theory = a well-tested and widely accepted explanation,
validated by much previous research
Paradigm = a dominant view. May shift if new results
show old results or assumptions to be wrong
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Ethics
Ethics is a discipline that
deals with how we value
and perceive our
environment.
Ethics influence our
decisions and actions.
Figure 2.1
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Worldview
Worldview = a person’s or group’s beliefs about the
meaning, purpose, operation, and essence of the world.
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Some questions in environmental ethics
Should the present
generation conserve
resources for future
generations?
Is it OK to destroy a
forest to create jobs
for people?
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Are humans justified
in driving other
species to extinction?
Is it OK for some
communities to be
exposed to more
pollution than others?
Three ethical worldviews
Ecocentric: Denote a nature-centred, as opposed to human-centred, system of values.
Biocentric: The value of non-human life in nature
Anthropocentric: Humans as the central element of the universe.
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Early environmental philosophers
The industrial revolution inspired reaction.
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The preservation ethic
John Muir (right, with President Roosevelt at Yosemite)
advocated preserving unspoiled nature, for its own sake
and for human fulfillment.
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The conservation ethic
Gifford Pinchot advocated using natural resources, but
exploiting them wisely, for the greatest good for the
greatest number for the longest time.
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The land ethic
Aldo Leopold urged people to view themselves as part
of nature, and to strive to maintain “the integrity,
stability, and beauty of the biotic community.”
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Environmental justice (EJ)
Poor people and minorities suffer more than their share of
environmental problems, EJ advocates say.
The EJ movement began with a protest against a toxic waste dump
in an African-American community in North Carolina.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Sustainability
The key concept for our future:
Limiting human impact on the natural
world so that our civilization can
continue to exist.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Sustainable development
UN: Development that “meets the needs of the
present without sacrificing the ability of future
generations to meet theirs”.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Conclusions: Challenges
We live on a planetary island with limited
resources.
Population and consumption are growing.
Many feel that we have not yet developed
the ethical basis for sustainability.
Environmental justice remains a challenge.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Conclusions: Solutions
We are developing ideas and technologies
to lessen our impacts.
We can
reduce
consumption.
population
and
Sustainability is catching on.
Science helps us understand our world
and develop solutions.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Conclusions: Solutions
Environmental science is vibrant and growing.
Ethics evolve, and we may yet develop an ethical
basis for sustainability.
Advances in technology and efficiency can
mitigate our environmental impacts.
Advances have been made toward environmental
justice.
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings
Copyright © 2005 Pearson Education, Inc., publishing as Benjamin Cummings