sponge what is environmental science? how has man influenced the environment through the ages? 1
TRANSCRIPT
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.
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 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
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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
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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SpongeWhat are renewable and nonrenewable
resources and give an example of each?How do we determine how resources are
allocated?What is the tragedy of the commons?
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SpongeHumans have influenced 83% of the
Earth’s surface. Does this number seem like a lot or a little? Some areas are more vulnerable to human influenced than others- why might this be?
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Exit TicketAmerican make up 5% of the world’s population,
own 30% of the world’s cars, and consume 25% of the world’s energy. By their first birthday, the average American will be responsible for more carbon dioxide emissions than a person in Tanzania generates in a lifetime.
Why do different cultures use and consume things at different rates? What do these numbers indicate about contemporary American culture?
“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 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. 22
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 EuropeDeveloping Countries: lower average incomes, simple and agricultural-based economies, and rapid population growth.Ex: Ethiopia, China
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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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