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 resourcesenvironmental education and communicationenvironmental research

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Biodiversity: Renewable Resource: 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 species are alive today.

Mass Extinction: Large scale extinction (some

natural and some man made)

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A resource that can be replaced relatively quickly by natural processes. ex. Fresh water, air soil, trees, crops

Nonrenewable Resource:A resource that forms at a much

slower rate than it is consumed

Agriculture: Agriculture Revolution: The practice of growing,

breeding, and caring for plants and animals that are used for food, clothing, housing, transportation, etc.

Dramatic changes that impacted human societies and their environment when man began practicing agriculture more than 10, 000 years ago.

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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.

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 ageDisease (similar to influenza or rabies) was introduced with the arrival of humans

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Hunter-GathersPeople who obtain food by collecting plants and

by hunting wild animals / scavenging their remains

Usually migrated from place to placeStill some remain in Amazon rain forestCleared grassland by setting fires

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 eatGrasslands, forest, and wetlands were replaced

with farmland (**habitats were destroyed)Caused floods, water shortage, infertile soil

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Industrial Revolution

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 transportationUrban areas grew –people moved from farms

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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 Shared 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 EnvironmentSupply 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 ContinuedCost 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. 16

Developed v’s Developing CountriesDeveloped 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.

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Population and ConsumptionEnvironmental 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 FootprintShows 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 WorldSustainability:

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. 20