Environmental
Science
Chapter 1
Notes
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Section 1:
Science and the Environment
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Environmental Science:
 Is a interdisciplinary field of science that draws from many
sciences (as well as other fields)
 Ex. Biology, chemistry, ecology,
geology, earth science, geography
 Is considered an applied science.
 Focuses on three main areas:
 conservation and protection of natural resources
 environmental education and communication
 environmental research
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Biodiversity:
 The number and variety of species that
live in the area.
 Earth has been home to millions of
species. Yet only a fraction of those
Renewable Resource:
A resource that can be replaced
relatively quickly by natural processes.
ex. Fresh water, air soil, trees, crops
species are alive today.
 Biodegradable:
 Are pollutants that can be broken down
by natural processes. Ex: food waste
 Non-degradable: pollutants that
cannot be broken down by natural
processes. Ex: plastics, lead, mercury
Mass Extinction:
 Large scale extinction (some natural
Nonrenewable Resource:
A resource that forms at a much slower
rate than it is consumed
and some man made)
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Agriculture:
 The practice of growing, breeding,
and caring for plants and animals
that are used for food, clothing,
housing, transportation, etc.
Agriculture Revolution:
 Dramatic changes that impacted
human societies and their
environment when man began
practicing agriculture more than
10, 000 years ago.
Closed System:
• Earth has been compared to a
“spaceship” traveling through space,
unable to dispose of waste or take on
new supplies as it travels.
• The only thing that enters Earth’s
atmosphere in large amounts is
energy from the sun.
• The only thing that leaves is heat.
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Species Extinction
• Three popular theories as to how and why the
megafauna (extremely large animals) ceased to exist
in North America:
 The blitzkreig (overkill) : they were over hunted
 Rapid climate shifts associated with the last ice age
 Disease (similar to influenza or rabies) was
introduced with the arrival of humans
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Hunter-Gathers
 People who obtain food by collecting plants and by
hunting wild animals / scavenging their remains
 Usually migrated from place to place
 Still some remain in Amazon rain forest
 Cleared grassland by setting fires
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Which of the following was not
caused by Hunter-Gatherers?
A) Clearing of land
B) Introduction of non-native species
C) Smog and industrial waste
D) Extinction of plants and animals
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Impacts made by the hunter-gatherers
 Changed the landscape by moving plants.
 Skeletal remains of hunter-gatherers from as many
as 20, 000 years ago show signs that these humans
were responsible for the pollutions of their
environment and even suffered deformities as a
result.
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Agricultural Revolution
 Caused human population growth, habitat loss, soil
erosion, domestication of plants and animals
 Changed the food we eat
 Grasslands, forest, and wetlands were replaced with
farmland (**habitats were destroyed)
 Caused floods, water shortage, infertile soil
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Industrial Revolution
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 Few restrictions were placed on air pollution during I.R.
(burning of fossil fuels became extensive – leading to
major pollution)
 Humans and animals had powered tools for almost
10, 000 years (prior to I.R.) now machines do.
 Greatly increased the efficiency of agriculture,
industry, and transportation
 Urban areas grew –people moved from farms
Main Environmental Issues
 Resource depletion
 Pollution
 Loss of biodiversity
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Section 2:
The Environment and Society
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“The Tragedy of the Commons”
 Written by Garrett Hardin (in 1968)
 Influential essay
 Described the relationship between the short-term
interest of the individual and the long-term interest of
society
 Overall point is that someone or some group has to
take responsibility for maintaining a resource
“If I don’t
use this
resource,
someone
else will.”
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Earth’s Modern Commons are our
“Natural Resources”
 Anything within the “Biosphere”
World’s Oceans / Waterways ; Air ; Migrating Animals ;
Forest ; Fossil Fuels / Nuclear Materials
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Economics and the Environment
 Supply and Demand: the greater the demand for a
limited supply of something, the more it’s worth.
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Economics and the Environment Continued
 Cost benefit analysis: balances the cost of the
action against the benefits one expects from it.
The cost of environmental
regulations are often passed
on to the consumer.
“The cost to clean up after an oil
spill is added to the price of gas”
 Risk Assessment: a tool to
help create cost-effective
ways to protect our health
and the environment.
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Developed v’s Developing Countries
 Developed Country: have higher average incomes,
slower population growth, diverse industrial economies,
stronger support systems.
 Include US, Canada,
Japan, and the countries
of Western Europe
 Developing Countries: lower
average incomes, simple and
agricultural-based economies,
and rapid population growth.
Ex: Ethiopia, China
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Population and Consumption
 Environmental problems in
developed countries tend
to be related to consumption.
 The major environmental
problems in developing
countries are related to
population growth.
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Ecological Footprint
 Shows the productive
area of Earth needed to
support one person in a
particular country.
 It estimates the land
used for crops, grazing,
forest products, and
housing.
 It also estimates the
ocean area used to
harvest seafood and the
forest are needed to
absorb the air pollution.
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A Sustainable World
 Sustainability: the
condition in which
human needs are
met in such a way
that a human
population can
survive indefinitely.
 Is a primary goal of
environmentalist.
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