The following notes are to provide some background and focus for getting started in the five mini-study areas. They are in no way comprehensive, but are given only to help get into the work of the mini-studies.
It is important to remember that the purpose of having students write and work with mini-studies is to provide a general background of information to use throughout the unit. Students will bring in different material for the topics and from this the work in each area will develop.
Mini-Study #1: The Water cycle and Water Pollution.
There is a fairly constant supply of water on earth and it moves about constantly in what is referred to as the hydrologic cycle. Water flowing and circling around the earth illustrates the interconnectedness of all things. It also illustrates how easily pollution can encircle the earth.
About 2/3 of the earth is covered with water and less than 1% is available to us as fresh water. According to one estimate, that is about 9,000 cubic kilometers, which is enough to sustain about 20 billion people. 16 That’s the good news. The bad news is that it is not evenly distributed and it is being badly polluted.
Polluted water makes people ill, kills fish, destroys rivers and lakes, ruins animal habitats, decreases the quality of drinking water, destroys recreational areas, and decreases the quality of life at all levels.
Some of the major causes of water contamination are sewage, hazardous waste, leakage from landfills, agricultural practices, farm factories, effluent from industries and leakage from underground storage tanks.
About 50% of the U.S. population depends on groundwater for drinking water. Increasingly new sources of groundwater pollution are being reported. Our primary sources of groundwater pollution are as follows.
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192,000 Surface impoundments (ponds, pits, and lagoons which have been built to store waste-many of them hazardous wastes)
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9,000 municipal landfills
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280 million acres of cropland treated with pesticides
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50 million tons of fertilizers/year
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23 million septic tanks
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10 million tons of dry salt applied to highways/year
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5 million underground storage tanks, underground injection wells oil and drilling operations
There are two areas of focus for consumers, conservation of water and keeping water clean. See Activity #4: a Water Conservation Problem for reasons why we want to conserve water. Suggestions to prevent polluting water are as follows. (1) Don’t empty pollutants from home into drains or outside in the yard. Things like paint, toxic cleaners, and motor oil should be disposed of in the city’s hazardous waste collection. (2) Buy products that don’t pollute. This may require research. (3) Read labels. (4) Report pollution.
Mini-Study #2: Energy
Some of our current energy concerns are (1) the impact on the environment from extracting fossil fuels and generating energy, (2) the amount of greenhouse gases produced in energy generation, (3) limited amounts of fossil fuels and uranium, (4) dependence on other countries for fuel, and (5) the claim of future generation for the resources we are using.
For environmental purposes, it is important to keep in mind that energy can be produced from either renewable sources such as solar, wind, water, and wood, or nonrenewable sources such as oil, gas, coal, and uranium. Norway uses 100% renewable energy sources to produce its electricity. At the other extreme, Denmark uses only 1% renewable and 99% nonrenewable (99% fossil fuel) for their electricity. The U.S. uses about 6% renewable and 94% nonrenewable (20% nuclear and 74% fossil fuel).
Mini-Study #3: Air Pollution.
Air pollution in general is caused by the thousands of tons of toxins that are dumped into the air each year primarily from motor vehicles, power plants, and other industries including farming and agriculture. It causes illness and death in people, damage to trees and wildlife, and corrodes buildings and other structures.
Ozone depletion
, acid rain, and global warming are three aspects of air pollution commonly talked about today. Students mini-studies on air pollution might include information on any of these.
Ozone deletion refers to the fact that the ozone layer, which is about seven to fifteen miles above the earth’s surface, has been thinning to the point that holes have developed. This is believed to be caused primarily by chlorofluorocarbons (CFCs) which are widely used in refrigeration, air conditioners, Styrofoam, solvents and as propellants in aerosols. The gas halon, less well known but even more destructive to ozone, is also a cause. Halon is used primarily in fire extinguishers.
Near earth, CFCs are relatively inert. But when not properly disposed of, as happens when refrigerators and cars with air conditioners are dumped into landfills, the CFCs escape into the air and slowly rise, taking any where from 10 to 100 years, until they penetrate the ozone layer. At this point they become radiated by the sun’s energy and actively begin destroying ozone molecules.
The reason for concern is that the ozone layer acts as a filter and filters out the sun’s harmful ultraviolet rays. As the layer gets thinner, more UV rays reach earth and are believed to be causing an increase in skin cancer and cataracts in people, possibly similar effects in animals, and diseases in plants.
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Johnson and Sons has produced a video called
Ozone: The Hole story
. It explains what the ozone problem is, its cause, the increase risks related to it, and discusses ideas on easing the problem. However, it also is an example of how industry can skew facts and make suggestions that mitigate the problems their products cause.
Acid Rain
. Acid rain is caused by sulfur dioxide and nitrogen oxides from the burning of fossil fuels. Once they are emitted into the air, they mix with moisture and become sulfuric acid and nitric acid. The effects of this are an increasing threat to human health, acidification of lakes with loss of fish and wildlife, die-back of forests, stunting of crops, and corrosion of buildings.
Global Warming
refers to the idea that the Earth’s atmosphere is increasing in temperature. Even though the earth’s average global temperature has stayed fairly constant for thousands of years, some scientists are predicting an increase of 4 to 9 degrees in the next 70 years.
If this does happen, some possible results would be the melting of the polar glaciers, a rise in sea level of 5 feet, coastal flooding, and significant change in climate conditions. The cause of global warming is the increase of motor vehicle and industrial waste being put into the air.
Mini-Study #4: Discard Management.
As a culture we are producing and consuming so much so fast and in such a careless way that we can’t get rid of what we have produced fast enough. Our landfills are being filled to capacity and no one wants a new landfill to be placed near where he or she lives. Landfills have had all kinds of hazardous waste dumped into them and some of the hazardous waste seeps into the ground water and water systems on which people depend for drinking water. Spent nuclear rods take something like 500,000 years to become safe. Hauling garbage away is expensive. Pollution of rivers and streams kills fish. Most of our current landfill methods do not allow garbage to decay so much of it is being preserved. The problems of trying to disposal of solid waste are many. However, that’s the bad side of the story. Today a lot is being done to decrease waste and pollution and save resources. Some points to be made in this area are as follows.
Consider the terms “garbage,” “trash,” and “waste.” They all have a negative connotation and imply a lack of value. Discards imply things people no longer want. The things could or could not have value. Discarded resources implies a reserve, supply, a store of things or stuff that people no longer want. So discard management refers to the handling or controlling of what we discard, or no longer want. It more accurately represents what is starting to happen today than the phrase “solid waste management.”
Another point to consider is that garbage is something we manufacture. A Coke can in your hand isn’t garbage, it’s an aluminum can. When you throw it into a waste basket with all kinds of other discarded things, then it becomes garbage.
The Green Consumer movement even has its own “Three R’s,” and for some even ‘Four R’s.”
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1. Refuse—to buy wasteful and polluting products
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____
- this is where green power is the strongest
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- is also known as precycling
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2. Reduce—How much is enough?
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- How much packaging, junk mail, toys, and gadgets do we need?
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- How much credit and debt can we afford?
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3. Reuse—buy products with the longest life possible so they can be reused over and over
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4. Recycle—After we refuse, reduce, and reuse, a high percentage of what is leftover discard should be recyclable
Why should we recycle? To save material, energy, and the cultural value of things. It also creates more jobs to recycle than to make new. It saves money too.
If after refusing and reducing we have things to dispose of, the choices we have are to reuse, recycle, landfill or incinerate.
Mini-Study #5: Wilderness Depletion.
Wilderness depletion is probably the most difficult for many of us to understand because so few of us are exposed to real wilderness. By its very nature the wilderness is not controlled by humankind but operates on its own natural laws. Two videos that clearly and beautifully portray the wilderness sense and struggle are
The Wilderness Idea
and
The Garden of Eden
.
The Wilderness Idea
is a video documentary that portrays the first great wilderness battle between John Muir and Gifford Pinchot over whether the Hetch Hetchy, a valley within Yosemite National Park, should be dammed and flooded to form a reservoir for San Francisco. This battle took place in the early part of this century.
A second documentary,
The Garden of Eden
, portrays a current wilderness battle to save a Florida forest which housed rare species of plants and animals and some that are found no where else. It interviews the environmentalists, community people, and an electrical company executive as the drama unfolds as to whether or not the new power plant would be built as scheduled in the Garden of Eden.
The rainforest destruction which we hear so much about is part of the deeper, more general problem of wilderness destruction. The destruction of the rainforest is caused by many factors: the clearing of the forest to support cattle and cash crops to pay off debt, poor government planning, poorly planned attempts to satisfy demands for land reform, a demand for tropical wood and the clearing of the forest by people trying to subsist by farming land that is not suited for it.
The destruction of the rainforest causes many problems. The rainforest are home for many people and a large variety of animals and plants found nowhere else on earth. They are major climate regulators and a source of many medicines, seeds, herbs, rubber, and a vast number of yet unknown plants, insects, and animals.
But wilderness destruction is worldwide. In the U.S. we have destroyed over 80% of our natural forest and almost all of our great plain natural prairies. As a people we are only now beginning to understand what this means.