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Chapter 21 Environmental Problems and Solutions

Pollution – the presence of harmful substances in the environment. These substances (pollutants) may be solid, chemicals, noise or heat. Pollutants can damage and kill plants and animals and the habitat that they live within. Pollutants can also harm humans.

Garbage

Americans produce more household garbage than any other country. If we gathered all of the aluminum cans we use in one year, and stacked them on top of each other, they could reach to the moon and back 17 times “WOW”. WE HAVE A PROBLEM! These aluminum cans could be recycled and this would save over 50% of the energy required to make cans from the ore bauxite we get from the Earth. We also send our household wastes to landfills and it is estimated that on average each American family throws away 12 kilograms of trash each week. This is about 26.5 pounds of waste per day. We can recycle about 70% of this relatively easily if we put forth the effort.

Billions of kilograms are classified as hazardous wastes each year, which means it is harmful to the environment, and to organisms including humans. A few industries that produce hazardous wastes include paper mills, nuclear power plants, oil refineries, plastic and metal processing plants, and hospitals. We should all take the blame for this, not just the industries. We consume the products these industries produce and then we use the products in our homes. When we use the products, we create wastes that are hazardous. Many home cleaners, detergents, batteries, paint, and other forms of home waste are dangerous to the environment and the organisms.

Following Our Waste Stream

Many people never consider where the waste they generate goes to. The waste we generate in our homes usually finds it’s way to the landfill(s). The wastes in the landfills are often covered with soil. Most landfills have to meet federal rules, but years ago we did not know what would occur to the wastes placed into these landfills. Well, we have found out that many of the wastes in liquid form end up seeping into ground water or seeping into lakes, rivers, and streams and polluting the environment. New landfills must have a liner that prevents this from happening, but what about all the chemicals that combine in the landfills. Just because something is out of sight does not mean it is not dangerous.

Hazardous wastes are sometimes burned, and if done improperly the wastes can end up in our air. It is now illegal to dump hazardous wastes into our rivers and streams, but years ago we did not know the danger of doing such practices. Many rivers that were filled with hazardous chemicals are now being cleaned up and some that were void of certain fish species have recovered to have healthy populations of these fish again.

Chemicals Are Not All Bad

Chemicals are not all bad, many are very useful in treating illnesses, making plastics, thermometers, hair spray, paints, to help preserve foods, cure diseases, and many other beneficial uses.

Some chemicals are used to control pests that damage crops. These chemicals are called pesticides and many are used in agriculture. These pesticides are released into the environment and if not properly used can get into waterways, and the soil. In the 1940’s and 1950’s Rachael Carson wrote a book called Silent Spring. This brought about the awareness of the misuse of pesticides. We were polluting the environment with pesticides. Many birds almost became extinct, like the Bald Eagle, because the pesticides were getting into the animals bodies and when they laid their eggs, the egg would break instead of having a hard shell the birds could sit on and incubate. Many bird populations declined due to this. Rachael Carson is considered the “fountainhead” of the environmental movement because she made Americans aware of the problem with her book. Unfortunately she died from cancer and never realized the impact she had on improving our environment.

One class of chemicals are Chlorinated Fluorocarbons (CFC’s) that was used in aerosol spray cans, refrigerators, and plastics became unlawful to use due to their destruction of the ozone layer. These chemicals would rise into the atmosphere and destroy the ozone layer. The ozone layer protects us from the ultraviolet radiation (light) the sun emits.

Another class of chemicals called poly-chlorinated biphenyl’s (PCB’s) were used as a source of insulation, placed in paint, and used in household appliances. Scientists discovered that these chemicals are poisonous and it is now unlawful to use PCB’s. These chemicals are still in the environment because they do not break down or decompose rapidly. Some places are very much polluted with this chemical.

Nuclear Wastes

Nuclear power plants also produce hazardous wastes when they make electricity for our homes, schools and businesses. Some of the wastes are radioactive wastes, which take hundreds to thousands of years to become harmless. These wastes can cause cancer, leukemia, and birth defects in humans. Why do we use them you ask? Because humans believe the benefit of using nuclear energy to make electricity is greater than the risks involved when we use nuclear power plants.

Carbon Dioxide in Our Atmosphere

The Earth is surrounded in our atmosphere by a “blanket of gases” that keep out ultraviolet radiation and carbon dioxide is one of the gasses we find in the atmosphere. The problem is that since we have been keeping record of the percent of carbon dioxide in the atmosphere, we have noticed it has increased about 25%. This “insulates” the Earth and prevents some of the heat from escaping our atmosphere and the global temperature is increasing. The carbon dioxide acts like a greenhouse and keeps the earth warm. Compare to an experience: If it is real cold outside and you enter a car on a sunny day. The car is often very warm because the glass acts as a greenhouse (it traps the heat inside the car). Well, carbon dioxide in our atmosphere acts very similar.

What problems can result? When the global temperatures rise, the polar ice caps can warm and begin to melt, which could lead to the seas rising. Scientists think that if the trend continues the sea level could rise 10 centimeters to 1.5 meters by the year 2100. If this occurs, many of our coastlines would flood. The growing “belt” of continents would change as the climate warms and changes. Many productive agricultural lands may become too dry to grow crops. The problems can continue to mount.

Noise Pollution

Noise pollution is when sounds are loud enough to cause problems for organisms. Loud noises for humans can cause headaches, loss of hearing, distractions in places safety is very important as well as psychological problems when we are exposed to noise pollution.

Losing Our Resources

The Earth is a finite “closed system”, we do not get more resources from somewhere else. The resources are cycled. Resources do however change form. Example when oil is pumped out of the ground and refined is can be turned into gasoline and other products. When we burn the gasoline, it is changed into gasses and heat. The form has changed. Our current problem is we are using resources faster than nature can produce them. When this happens, we call the resource nonrenewable.

If we are using the resource at the same pace that nature provides the resource, we will never run out and the resource is said to be a renewable resource. If we harvest trees for products at the same rate we can grow them, then trees can be a renewable resource. Most of the resources are considered nonrenewable if mining is involved in manufacturing products from the resource.

We used to think many resources like forests were renewable, but the tropical rain forests as well as many forests in the U.S. are being cut down faster than they can re-grow. This makes the forests nonrenewable. Another resource that is now considered nonrenewable is ground water. We are extracting (pumping) ground water our faster than it is recharged by nature. Some water sources are being polluted at a faster rate than nature can clean them up, so they too are becoming nonrenewable.

Alien Species

When an organism is introduced to a new environment that normally does not occur there, we say the species is an alien species. Example: if we turned loose thousands of kangaroos in America, they would be considered aliens because they normally do not occur here. This type of problem has occurred with other organisms like honeysuckle, kudzu, the starling bird, the Eurasian collared dove and other animals and plants. It may not necessarily be they were brought into the ecosystem from another country; simply they were transferred from one ecosystem to a different one that the species normally do not occur. Most alien species cause problems with native species. They often out-compete for food or space and the native species suffer.

Human Population Growth

In 1800, there were 1 billion people in the world. In 1990, there were 5.2 billion people. It is estimated that in 2100 there will be 14 billion. Today, there are people starving to death in many countries. What will happen as the population keeps increasing exponentially? More starvation, diseases, and illnesses? How will we be able to produce enough crops for the population when we cannot keep it up currently? Time will tell what will happen. Has the human population already reached carrying capacity?

Overpopulation occurs when the number of individuals becomes so large that they cannot get all of the food, water and other resources they need on an ongoing basis.

Habitat Destruction

The key to habitat of any type is the biodiversity that is found in the habitat. Biodiversity means “variety of life”. So biodiversity references the number of different species of organisms found in a particular habitat. The greater number of species in a particular habitat, the more biodiversity the area has. When habitat is destroyed, biodiversity is lost or goes down.

Forests and Diversity and Destruction

Recall: Trees give off oxygen when they carry out photosynthesis. They also give us lumber to build things with, provide nuts for food, provide cellulose for making paper, provide the chemicals for turpentine, resin for rubber, alcohol, pencils, telephone poles, and many other uses. Trees are a vital part to every person’s life. Deforestation is the removal of forest and it is occurring worldwide faster than it ever has. People are clearing tropical forests to plant crops on, but the soil is so nutrient poor that the farmers can only grow crops about two years before having to convert more tropical rain forest to farmland. The “used up” land is often abandoned and the soil erodes away and may take hundreds to thousands of years to recover if it ever does recover.

Wetlands and their Destruction

Wetlands are also a very an environment that contains much biodiversity. Humans are unfortunately draining wetlands to convert the land into farmland and this results in a great biodiversity loss. When wetlands are in their natural state, they help prevent flooding, provide habitat for many waterfowl, and filter pollutants from the water that flows through the wetland. Wetlands are also drained for building sites for homes, shopping malls, and many other destructive purposes. Wetlands can also be destroyed if we overload them with pollution.

Marine Habitat Destruction

The main cause of marine habitat destruction is oil. Oil comes from ships spilling the oil in our oceans, draining off our streets into waterways that lead to the ocean, and sometimes oils have been dumped into the oceans to mention a few. Remember from social studies that all the oceans are ultimately connected so the oil can spread from one ocean to another and end up all around the world.

Plastics are another pollutant in the oceans. Plastic bags resemble jellyfish and sea turtles feed on jellyfish. When the sea turtles try to eat the bags, their digestive system becomes clogged and they starve to death. The rings of plastic around soft drink cans create problems for marine life. The plastic rings get caught around the organism and as the organism grows, the ring cuts into the organisms body and infections can result that lead to death. Marine birds often get the plastic rings caught around their neck and die. Plastic beads often resemble eggs of different fish and when organisms eat the beads that get into the oceans, they die also.

Plastics are often NOT biodegradable, in other words they do not decompose or break down.

Destruction Effects on Humans

Humans are also affected by habitat destruction and pollution getting into the environment. If humans drink polluted water, we get sick and may even die from the illness. Sometimes we do not detect the damage for many years after the pollution is in the environment. Some pollutants cause cancers, birth defects, and mutations in humans. Any pollutant that harms organisms in the environment will also end up harming humans over time. We must be good stewards (caregivers, or caretakers) of the environment in order to prevent being affected by pollution.

SECTION 2 All Is Not Bad

So far you have heard about many bad and destructive results regarding our environment. There is good news. Humans can work together and often find solutions to the problems and work toward correcting those problems. We have learned from past mistakes and try to prevent those types of mistakes from occurring again. We are trying to clean up many of the problems we created, like the pesticide problems.

Conservation Not Preservation

There is a difference that many people have trouble understanding. Conservation and preservation do not have the same meanings. Conservation is the use of resources without abusing the resource and preservation is when we do not use the resource and try to keep it in its original state. Preservation is not always the answer. Example: People want to “preserve” the Yellowstone National Park. If we practice preservation, that means we MUST let nature take its course. If a fire breaks out from a natural lightening strike, we should let the park burn under the sense of preservation. Many people say they are preservationists, but when a natural disaster occurs in the environment, they are often the first people that want to interfere with what is going on.

Most people that truly understand the relationships of the environment agree that conservation is often the best method. We should use the resource, but use it to the best of our ability that we have. In other words, if we burn coal, we should use the newest technology we have to prevent the damaging of the environment. We often have much safer methods to protect the environment than we use. Why do we do this? Because it costs a great deal of money to use the best or safest practices we have.

Three ways we can practice conservation is through REDUCE, REUSE, and RECYCLE.

REDUCE

The easiest and most apparent way to practice conservation is to reduce the waste and pollution we produce. We can reduce at least one-third (33%) of our waste by reducing the packaging. Can you think of a food that you have to open a package and then open another package before being able to eat the product? This is “over packaging” of products. We can wrap the products in less paper and plastic to reduce this waste.

Some companies are searching for less hazardous materials to use in making their products. Some people are trying to not use many chemicals that are available (example: many farmers are choosing not to use pesticides and herbicides in their fields and use organic farming). Organic products often cost more, but do not have pesticide or chemical residues on them.

Scientists are also searching for methods to use less of the nonrenewable resources for completing tasks. Example: producing vehicles that use less fuel. Many research projects are in the business of finding alternative fuels or alternative sources of energy. Solar energy is an example of an alternative energy source. We also have scientists learning how to use ocean currents to drive turbines in order to produce electricity.

Everyone should be involved in taking responsibility to reduce the resources we use. Large companies, small companies as well as private individuals have the responsibility to reduce how much waste we generate.

REUSE

Many products that we use can be reused over and over again. Example: clothes can be given to others to wear when people out grow them. Many types of equipment can be repaired instead of simply throwing it away. By reusing materials we are helping to conserve the resources we have.

We can reuse many plastic products. When we reuse plastic bags over and over, we do not have to make extra bags. When we use rechargeable batteries, new ones do not have to be made for replacements as often. When reuse products we are conserving resources and reducing the amount of pollution.

Water is one of the most important resources we have. Water can be reused if we treat it and “clean it up” after each use and prevent it from becoming a hazardous waste. About 85% of the water we use in our homes is sent down a drain of some sort. This water can often be sent to a wastewater treatment plant and cleaned up to be reused. Many cities that have very limited water supplies (especially in California where there is little water available) send the wastewater to a treatment plant and from the treatment plant it goes to a water filtration (treatment) plant and sent back to customers homes, businesses and places of work.

Much of the water that is sent down a drain is not dangerous and could potentially be used to water lawns and agricultural crops.

RECYCLING

Recycling is a form of reuse, but the product may be recycled into a totally different product. Example: We can now take plastic soda bottles and recycle them into carpet, clothing and lumber. Glass containers can be recycled. In Japan, many of their glass containers are simply sterilized and refilled with consumable products.

We can also recycle many forms of trash. Paper bags, newspapers, and many other forms of paper products can be recycled into new paper products. The paper products that have had food contact cannot be recycled because in order to kill the bacteria and other harmful pathogens we must heat the paper up. When we heat the paper to the proper temperature to kill these organisms, the paper will burn and you lose the product.

Aluminum drink containers can be recycled into new cans or other aluminum products. Lead batteries like cars have can be recycled.

The waste that can be burned can be placed into incinerators, which heat water to make steam to drive a turbine and create electricity. Recycling is easy, but people often do not choose to try and recycle. Many cities and states require recycling products in order to save landfill space.

Maintaining Biodiversity

Remember: the more species an area has, the more biodiversity the area has. Let’s look at an example of biodiversity. If we had a forest with one species of tree and some natural disaster occurred, the one species may not survive. It probably would not survive.

On the other hand, if we had a forest with 40 different species of trees and the same natural disaster occurred there is a chance that some of the species would survive. In this situation, we would maintain some biodiversity compared to the forest with one species and all of the trees died (zero biodiversity).

Each species in an ecosystem serves a particular role or niche. Some species are predators, some are prey, some form symbiotic relationships, some decompose dead organisms, and you can probably name many other roles organisms play in a generic ecosystem. The point is that all organisms play an integral or important part in the ecosystem for the ecosystem to function properly.

Protecting Species

Many species must be protected in order to maintain biodiversity. When species populations get smaller it may be necessary to place the species on the Endangered Species List. The organisms on the Endangered Species List have a high chance of becoming extinct if we do not protect them. Plants and animals are on the Endangered Species List. It takes a long time to get an organism listed on the Endangered Species list due to all of the paperwork and having to present the information to the government. Sometimes the species may actually become extinct before all of the steps can be taken to place the species on the endangered list. Can you think of any endangered species? Here are a few: the White Tiger, California Condor, Whooping Crane, and a bat called the Indiana myotis. Bald eagles are still protected, but they have been placed on a “Threatened List” and removed from the Endangered List.

We can often protect specific habitat in order to save a species from becoming endangered or extinct. Species that are not currently threatened or endangered must also be protected so we have laws that regulate the harvesting of these animals during hunting seasons, and we protect habitat to protect species.

How Can You Help?

Reduce any pesticide use you may do. Use the natural pesticides on the market instead of man made chemicals.

Reduce pollution by prohibiting the dumping of wastes into rivers, streams, and forests, or other ecosystems.

Protect habitats by not doing any destructive activities when using resources or being involved in an activity that could damage habitat.

Enforce protection laws, especially the Endangered Species Act.

Develop alternative energy sources and make more efficient use of the resources we currently use.

Purchase products that can be recycled or reused. Do not use extra resources when you do not need them. Reduce the amount of resources you depend on. Repair leaking pipes and faucets in homes, and businesses. Use biodegradable products, use cloth products that can be washed instead of paper that is thrown away (napkins, hand towels), use rechargeable batteries, turn off lights not being used, walk or ride a bicycle to other locations, and use lunch boxes instead of a new bag to carry lunches in everyday. These are a few of the many ways we can conserve our resources and preserve the environment.

Chapter 21 Study Guides Environmental Problems and Solutions

SECTION 1

1. P is the presence of harmful substances in the environment.

2. The substances referred to in question one can be in several forms, list the four forms we read about.

3. The Americans produce more waste products than any other c in the world. So much in fact that that it could stretch to the moon _______ times.

4. Most of the household wastes end up in giant l .

5. Chemicals are found e . Some chemicals are very beneficial, while others can be very dangerous and deadly.

6. R C was the lady responsible for bringing about awareness of the pesticides.

7. C ‘s and P ‘s are two groups of chemicals that have been identified as being very harmful in the environment. They have now been banned in the United States.

8. R wastes are special kinds of hazardous wastes that take hundreds and even thousands of years to become harmless.

9. Since the late 1800’s the gas c d has increased in our atmosphere by 25%, which scientists believe can result in global temperature.

10. N pollution can result in affects to human senses. It can result in headaches and loss of hearing.

11. A resource that can be used again and again or used at the same rate it can be produced is called a r resource.

12. A resource that can only be used one time like coal, natural gas, or other petroleum products are considered n resources.

13. There used to be some resources we considered renewable, but now are considered nonrenewable. What are two examples that the book talks about? We read about these.

14. An organisms that makes a home for itself outside of it’s natural “home range” is considered an e .

15. O occurs when the number of individuals becomes so large that they can’t get all the food, water, and other resources they need on an ongoing basis.

16. B refers to “variety of life” or how many different species occupy an ecosystem.

17. D is the clearing of forests, which over time may lead to more carbon dioxide in the atmosphere since we have a loss of trees.

18. List three reasons why wetlands are important. ______________________________________________________________________________________________________________________________________________________________________________________________________

19. O is the major contributor to the loss of marine habitats.

20. Things that are naturally broken down in the environment are b .

21. How can pollution in the environment cause health problems? List or explain a couple.

SECTION 2 Good News and Solutions

1. A major method that we can practice in order to help save the Earth is

c , which means the “use without abuse”.

2. The three “R’s” for conservation are r , r and

r .

3. What percentage of the wastes comes from cities and towns that are packaging?

4. List three examples of alternative energy “power” sources. 1.___________________________, 2)________________________ and 3. ________________________________.

5. Each citizen of the United States produces ___________ times more waste than a citizen of a developing country.

6. Know: Reusing materials is an excellent method to conserve resources and help prevent pollution.

7. What percentage of water used in homes “goes down the drain”. ______ Much of this water could be used to water plants and gardens without negative outcomes.

8. R involves breaking down trash and using it again, it may be in the same form or a different form of a product.

9. What are six common waste products that we could recycle instead of throwing them in the trash? ______________________________________________________________________________________________________________________________________________________________________________________________________

10. If we recycle aluminum foil, what percentage of the energy is saved instead of mining the ore and making the aluminum? _______________

11. The process of transforming garbage into electricity is known as _______________________ _____________________________. The garbage is often incinerated and used to produce steam, which turns a turbine and generator to make electricity.

12. The percentage of garbage recycled in the U.S. is ______________ percent compared to ______________ percentage in Europe and _____________ percentage in Japan.

13. Biodiversity keeps communities and ecosystems s .

14. What piece of government or Act is responsible for protecting organisms that could become extinct? E S A

15. One of the easiest methods to protect organisms is to protect the

h they live in.

16. Explain or list three ways you can practice conservation at your house.

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