Chapter 4

Environmental Problems and Solutions

Sect 1- Environmental Problems Pollution is an unwanted change in the

environment caused by substances, such as wastes, or forms of energy, such as radiation.

1. Garbage/Hazardous waste: includes wastes that can catch fire; corrode, or eat through metal; explode; or make people sick. Many industries, such as paper mills and oil refineries, produce hazardous wastes.

2. High-Powered Waste: Nuclear power plants provide electricity to many homes and businesses. The plants also produce radioactive wastes.

3. Chemicals: Chemicals are used to treat diseases, in plastics and preserved foods.

The same chemicals that help people may harm the environment.

CFCs and PCBs are two groups of harmful chemicals. Ozone protects Earth from harmful ultraviolet light. CFCs destroy ozone.

CFCs were used in aerosols, refrigerators, and plastics.

PCBs, was once used in appliances and paints. PCBs are poisonous and may cause cancer. Both CFCs and PCBs are banned but traces can

still be found in the atmosphere.

4. Gases: Earth’s atmosphere is made up of a mixture of gases. The atmosphere acts as a protective blanket. It keeps Earth warm enough for life to exist.

Since the Industrial Revolution, however, the amount of carbon dioxide in the atmosphere has increased. Carbon dioxide and other air pollutants act like a greenhouse, trapping heat around the Earth.

Many scientists think the increase in carbon dioxide has increased global temperatures.

5. Noise: Some pollutants affect the senses. These pollutants include loud noises. Too much noise is not just annoying.

Noise pollution affects your ability to hear and think clearly. And it may damage your hearing. People who work in noisy environments, such as in construction zones, must protect their ears.

Resource Depletion Renewable Resource: is one that can be

replaced at the same rate at which the resource is used.

Solar and wind energy are renewable resources, Non-renewable Resource: is one that cannot be

replaced or that can be replaced only over thousands or millions of years.

Most minerals and fossil fuels, such as oil and coal, are nonrenewable resources.

Nonrenewable resources cannot last forever. These resources will become more expensive as they become harder to find.

The removal of some materials from the Earth also carries a high price tag. This removal may lead to oil spills, loss of habitat, and damage from mining.

Some resources once thought to be renewable are becoming nonrenewable. Scientists used to think that fresh water was a renewable resource.

However water supplies are being used faster than they are being replaced

Human Population Growth Advances in medicine, such as immunizations,

and advances in farming have made human population growth possible.

Some people argue that there may eventually be too many people on Earth.

Overpopulation: happens when the number of individuals becomes so large that the individuals can’t get the resources they need to survive.

Scientists hope that populations level off before it gets to this point.

Habitat Destruction Biodiversity: is the number and variety of

organisms in a given area during a specific period of time.

Biodiversity can be measured in terms of: 1. Species richness 2. Evenness 3. Genetic diversity

Point-Source Pollution: pollution from one source

Non-Point Source Pollution: pollution that comes from many different sources.

Section 2- Environmental Solutions Conservation: is the preservation and wise use

of natural resources. 1. Reduce: As much as one-third of the waste

produced by some countries is packaging material. Products can be wrapped in less paper and plastic to reduce waste.

Biodegradable: can be broken down by living organisms, such as bacteria.

Agricultural specialists are also working on farming techniques that are better for the environment.

Reducing the Use on Non-renewable Resources

Some scientists are looking for sources of energy that can replace fossil fuels. Solar energy can be used to power homes.

Scientists are studying power sources such as wind, tides, and falling water.

Car companies have developed electric and hydrogen-fueled automobiles. Driving these cars uses fewer fossil fuels and produces less pollution than driving gas-fueled cars does.

2. Reuse: Reusing an item can reduce garbage overall by one-eighth.

Reusing water is vital to the survival of life on Earth. Many communities are experiencing water shortages. Some of these communities are experimenting with reusing, or reclaiming, wastewater.

One way to reclaim water is to use organisms to clean the water. These organisms include plants and filter-feeding animals, such as clams. Often, reclaimed water isn’t pure enough to drink. But it can be used to water crops, lawns, and golf courses.

3. Recycle: the recovery of materials from waste Plastics, paper, aluminum, wood, glass, and

cardboard are examples of materials that can be recycled.

Recycling aluminum saves 95% of the energy needed to change raw ore into aluminum. Glass can be recycled over and over again to make new bottles and jars.

Waste that can be burned can also be used to generate electricity in waste-to-energy plants. Using garbage to make electricity is an example of resource recovery.

Maintaining Biodiversity Biodiversity is also important because each

species has a unique role in an ecosystem. Losing one species could disrupt an entire ecosystem.

One way to maintain biodiversity is to protect individual species. In the United States, a law called the Endangered Species Act was designed to do just that. Endangered species are put on a special list.

The law forbids activities that would harm a species on this list. The law also requires the development of recovery programs for each endangered species.

Environmental Strategies 1. Reduce Pollution 2. Reduce Pesticide Use 3. Protect Habitats 4. Learn about local issues 5. Develop alternative energy resources The Environmental Protection Agency (EPA)

is a government organization that helps protect the environment. The EPA keeps people informed about environmental issues and helps enforce environmental laws.

Chapter 5

Energy Resources

Section 1- Natural Resources

Natural Resource: any natural material that is used by humans. Such as water, petroleum, minerals, forests, and animals.

Renewable Resource: a natural resource that can be replaced at the same rate at which the resource is consumed.

Nonrenewable Resource: a resource that forms at a rate that is much slower than the rate at which it is consumed.

Section 2- Fossil Fuels Energy Resources: natural resources that

humans use to generate energy. Fossil Fuel: a nonrenewable energy resource

formed from the remains of organisms that lived long ago; examples include oil, coal, and natural gas.

Energy is released from fossil fuels when they are burned. The energy is stored in the fossil fuel until it is burned.

Types of Fossil Fuels 1. Liquid Fossil Fuels: Petroleum-- a liquid

mixture of complex hydrocarbon compounds; used widely as a fuel source- More than 40% of the world’s energy comes from petroleum.

2. Gaseous Fossil Fuels: Natural Gas-- a mixture of gaseous hydrocarbons located under the surface of the Earth, often near petroleum deposits; used as fuel.- Most is used for heating, but is also used for generating electrical energy. Advantages to natural gas are a reduction in air pollution.

3. Solid Fossil Fuels: Coal-- a fossil fuel that forms underground from partially decomposed plant material.- Used more in the 1800s and early 1900s to heat homes, cook food and power trains. Once cleaner options became available, coal was not used as much die to its large amount of air pollution.

Stages of Coal Formation Stage 1: Peat Forms- 60% of peat is carbon Stage 2: Lignite Forms- When pressure and

temperature are increased on the peat it turns into lignite. 70% of lignite is carbon

Stage 3: Bituminous Coal Forms- When sediment is added, the pressure and temperature again increase. Lignite is changed into bituminous coal- 80% of bituminous coal is carbon

Stage 4: Anthracite Forms- When pressure and temperature increase anthracite is formed- 90% of anthracite is coal. Anthracite is the hardest coal.

Problems with Fossil Fuels 1. Acid Precipitation 2. Coal Mining 3. Petroleum Problems 4. Smog

Section 3- Alternative Resources 1. Fission: splitting the nucleus of a radioactive

atom- during this an extreme amount of energy is released--- CONS: remains of materials must be stored in an isolated areas for years until their danger is no longer.

2. Fusion: the joining of two or more nuclei to form a larger nucleus. CONS: extremely high temperatures are needed for this to occur.

3. Chemical Energy: the energy released when a chemical compound reacts to produce new compounds

4. Solar Energy: the energy received by the Earth from the sun in the form of radiation. This is a renewable resource because the Earth receives radiation constantly. Can be changed into electricity through the use of solar panels. PROS: no pollution CONS: panels are expensive

5. Wind Power: the use of a windmill to drive an electric generator. PROS: free, no pollution CONS: if no wind, no energy.

6. Hydroelectric Energy: electrical energy produced by falling water

7. Burning Biomass: Biomass: organic matter that can be a source of energy-- In developing countries, wood and animal waste are the primary sources of energy.

8. Gasohol: alcohol mixed with gasoline to generate energy for cooking, heating homes

9. Geothermal Energy: energy produced from the heat inside the Earth. This form of energy generation can be seen visually in the form of geysers.

This is the END of the NOTES!!!!