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CHAPTER 1UNDERSTANDING OUR

ENVIRONMENT

Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display.

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The Planet Earth

• Unique (?) in the universe

• Mild, relatively constant temperatures

• Biogeochemical cycles

• Millions of species

• Diverse, self-sustaining communities

PART 1: UNDERSTANDING OUR ENVIRONMENT

Earth – our frame of reference

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Environment - the circumstances and conditions that surround an organism or a group of organisms.

Environmental science - the systematic study of our environment and our place in it.

Ecology - the study of an organism or organisms, the impact of the environment on them, and their impact on the environment.

Environmental Science

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Part 2: Science as a Way of Knowing

• Modern science has its roots in antiquity

• Greek philosophers

• Arabic mathematicians and astronomers

• Chinese naturalists

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A Quote to think about regarding Ecology:

The reasonable man adapts himself to the world; the unreasonable one persists in

trying to adapt the world to himself.

Therefore all progress depends on the unreasonable man.

[George Bernard Shaw]

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A quote to think about regarding Technology:

The only two things that are infinite in size are the universe, and human stupidity. And I'm not completely sure about the universe.

[Albert Einstein]

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Scientific Investigation

• Deductive vs. inductive reasoning

• Hypothesis - a conditional explanation that can be verified or falsified

• Scientific theory - an explanation supported by an overwhelming body of data and experience

• Deductive reasoning – going from a general principle to a testable prediction about a specific case

• Inductive reasoning – taking many observations to discover patterns and produce general explanations

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Models and Natural ExperimentsModels• Simulate real environmental systems;• Physical or mathematical;• Provide heuristic information (suggestions of how

things MIGHT be); and• Are influenced by researchers' assumptions.

Natural Experiments• Gathering of historic evidence; and• Conducted by scientists who can't test their

hypotheses directly.

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• In some ways, children are the “ultimate” practical scientists…no pre-conceived bias in their investigations.

• However, Society uses numbers, called “statistics” to evaluate and compare things.

• Information known by only one person isn’t useful to Society, and communication is essential. This is one reason why scientists are rewarded so much for publishing in scientific journals. “Publish or Perish” is a

real threat in academia.

Open Minds are Learning Minds

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Statistics and ProbabilityQuantitative data• Precise and easily compared• Good benchmarks for measuring change.

Probability• Measure of how likely something is• High degree of scientific certainty: 95% probability.

Statistics• Important tool in both planning and evaluating scientific

studies• Sample size, number of replications important.

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Paradigms and Scientific Consensus

Paradigms • All-encompassing models of the world that guide our

interpretation of events• Examples: Einstein's theory of relativity, plate tectonics

Paradigm shift • When a majority of scientists accept that the “old”

explanation no longer explains new observations very well

• Paradigm shifts are sometimes contentious and political; often requires turnover of the “old guard”.

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Part 3: Thinking About Thinking

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Table 1.3 Steps in Critical Thinking

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Applying Critical Thinking• Identify and evaluate premises and

conclusions in an argument;• Acknowledge and clarify uncertainties,

vagueness, ambiguities, and contradictions; • Distinguish between facts and values;• Recognize and assess assumptions;• Distinguish source reliability or unreliability;

and• Recognize and understand conceptual

frameworks.

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Part 4. History of Conserva-tion and Environ-

mentalism

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Our Conservation and Environmentalism History has four Distinct Stages:

– Pragmatic Resource Conservation– Moral and Aesthetic Nature Preservation– Modern Environmentalism– Global Environmental Citizenship

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Pragmatic Resource Conservation

President Theodore Roosevelt and his chief conservation advisor, Gifford Pinchot, believed in utilitarian conservation.– Forests should be saved so they can be

used to provide homes and jobs.– Should be used for “the greatest good for

the greatest number, for the longest time.”

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Moral and Aesthetic Nature Preservation

John Muir, first president of the Sierra Club,

opposed Pinchot’s utilitarian policies.– Biocentric Preservation – nature exists for

its own sake, could care less about us– emphasizes the fundamental right of all

organisms to pursue their own interests– Creation of National Park Service

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Modern Environmentalism

Rachel Carson’s Silent Spring (1962) started

the modern environmental movement.– awakened the public to threats of pollution and

toxic chemicals to humans as well as other species

– modern environmentalism extends concerns to include both environmental pollution and use/misuse of natural resources.

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Global Concerns

Increased travel and communication enables

people to know about daily events in places

unknown in previous generations.

Global environmentalism is the recognition

that we share one environment that is common to

all humans.

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Part 5: Current Environmental Conditions

• Half the world's wetlands were lost in the last 100 years (a big problem in Louisiana bayou areas).

• Land conversion and logging have shrunk the world's forests by as much as 50%.

• Nearly three-quarters of the world's major marine fish stocks are over-fished or are being harvested beyond a sustainable rate.

• Soil degradation has affected two-thirds of the world's agricultural lands in the last 50 years.

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Major Causes of Environmental Degradation

(1) Population Growth

• Almost 6.5 billion people now occupy the earth, and we are adding about 85 million more each year.

• In the next decade, most population growth will be in the poorer countries - countries where present populations already strain resources and services

http://www.census.gov/main/www/popclock.html

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• burning of fossil fuels• destruction of tropical

rainforests and other biologically rich landscapes

• production of toxic wastes

(2) Resource Extraction and Use

Major Causes of Environmental Degradation (cont’d)

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Part 6: Human Dimensions of Environmental Science

• More than 1.3 billion people live in acute poverty, with an income of less than $1 (US) per day. These people generally lack access to an adequate diet, decent housing, basic sanitation, clean water, education, medical care, and other essentials.

• Four out of five people in the world live in what would be considered poverty in industrialized countries.

• The world's poorest people are often forced to meet short-term survival needs at the cost of long-term sustainability.

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The American Lifestyle

To get an average American through the day takesabout 1,000 pounds of raw materials, including• 40 pounds of fossil fuels• 22 pounds of wood and paper• 119 gallons of water.

Every year, Americans throw away some 160 million tons of garbage, including• 50 million tons of paper• 67 billion cans and bottles• 18 billion disposable diapers.

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SustainabilitySustainability

How can the nations of the world produce the goods and services needed to improve life for everyone without overtaxing the environmental systems and natural resources on which we all depend?

Sustainable development:progress in human well-being that can be extended/prolonged

over many generations, rather than just a few years.

To be truly enduring, the benefits of sustainable development must be available to all humans, not just to the members of a privileged group.

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Indigenous Peoples

Indigenous peoples are generally among the least powerful, most neglected groups.– In many countries, traditional

caste systems, discriminatory laws, economics, or prejudices repress indigenous peoples.

– In many places, indigenous people in traditional homelands guard undisturbed habitats and rare species.

– Recognizing native land rights may safeguard ecological processes.

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