Ch 6: Environmental Problems and Solutions p.154

Section 1: Environmental Problems Industrial Revolution (late 1700s): – People started to rely more and more on machines – as a result, more harmful substances entered the air, water, and soil

Types of Pollution  Pollution: an unwanted change in the environment  caused by: substances or forms of energy (radiation or volcanic eruptions)  may harm plants, animals and humans  Five types of Pollution: 1.Garbage 2. Chemicals 3. High-Powered Wastes 4. Gases 5. Noise

1. Garbage  Hazardous waste: wastes that can catch fire, corrode metal, explode, or make people sick  Produced by industries(paper mills, oil refineries)

2. Chemicals Fertilizer promotes the growth of algae. As dead algae decompose, oxygen in the water is used up. Fish die because they cannot get oxygen.

3. High-Powered Wastes  Nuclear power plants provide electricity but produce radioactive wastes.  Radioactive wastes : hazardous wastes that give off radiation that can take thousands of years to become harmless. Nuclear power plant Nuclear Storage Plant Drums of Radioactive Waste

4. Gases  CO 2 : acts as a protective blanket keeping Earth warm enough for life to exist  greenhouse effect: has caused the atmosphere to trap the heat around the Earth that has resulted in increased global temperatures  If temperatures continue to rise: 1. polar icecaps could melt 2.oceans would rise and coastal areas could flood

Resource Depletion 1. Renewable resource: can be replaced at the same rate the resource is used  Ex: Solar, wind energy and some kinds of trees (Christmas tree farm) Wind Mill Farm Solar Panels Christmas Tree Farm

Resources Cont. 2. Nonrenewable resource: cannot be replaced or that can be replaced only over thousands or millions of years  Examples: Most minerals and fossil fuels, such as oil and coal  Cannot last forever; will become harder to find and more expensive  The removal of some materials may lead to oil spills, loss of habitat, and damage from strip mining, as shown below. Minerals Coal Mines Oil Wells

Renewable or Nonrenewable?  Resources once thought to be renewable are becoming nonrenewable.  Ex: Fresh water supplies are being used faster than being replaced, so some areas may run out.

Invasive (Exotic) Species  Exotic Species: Organism that makes a home for itself in a new place outside its native home  Ex: Northern snakehead fish, kudzu, zebra mussels  thrive in new places because they are free from predators found in their native homes  so, they can become pests and compete with native species. Eating other fish, amphibians, small birds and mammals, it can move across land in search of water and could invade more lakes and ponds. It can also survive out of water for four days.

Human Population Growth  Factors possibly causing increase: 1.Advances in medicine-immunizations 2.Advances in farming

Habitat Destruction  Habitat: where an organism lives  Biodiversity: habitats have their own number and variety of organisms  If a habitat is damaged or destroyed, biodiversity is lost.

1. Forest Habitats  Deforestation: clearing of forest lands Trees provide humans with oxygen, lumber, food, rubber, and paper. For some of these products, such as lumber and paper, trees must be cut down. Deforestation is the clearing of forest lands, as shown in Figure 6. At one time, many of these cleared forests were not replanted. Today, lumber companies often plant new trees to replace the trees that were cut down. However, some biodiversity is still lost.Trees provide humans with oxygen, lumber, food, rubber, and paper. For some of these products, such as lumber and paper, trees must be cut down. Deforestation is the clearing of forest lands, as shown in Figure 6. At one time, many of these cleared forests were not replanted. Today, lumber companies often plant new trees to replace the trees that were cut down. However, some biodiversity is still lost. Fi g u r e 6 D e f o r e st a ti o n c a n l e a v e s o il e x p o s e d t o e r o si o n. T r o p ic al r ai n f o r e s t s, t h e m o s t d iv e r s e h a b it a t s o n E a rt h, a r e s o m e ti m e s cl e a r e d f o r f a r m la n d, r o a d s, a n d l u m b e r. B u t a ft e r a tr o p ic al r ai n f o r e s t is cl e a r e d, t h e a r e a c a n n o t g r o w t o b e a s d iv e r s e a s it o n c e w a s. A ls o, t h i n tr o p ic al s o il s a r e o ft e n b a d ly d a m a g e d.

Environmental Solutions: Section 2

Conservation  Conservation: the preservation and wise use of natural resources.  Ex: Use organic compost instead of chemical fertilizer in your garden thus reducing soil and water pollution.  Three ways to conserve Resources: 1. Reduce 2.Reuse 3.Recycle

Reduce  Waste and Pollution  1/3 of waste is packaging material  Nonrenewable Resources  Use sources of energy that can replace fossil fuels  Ex: Biofuels, solar energy, wind, tides, falling water, electric and hydrogen fueled automobiles Solar Wind Falling Water

Reuse  Reusing Products : An important way to conserve resources.  Examples: plastic bag: sandals, tires: handbags, building materials including wood, bricks, tiles Plastic sandals composite decking Brick Re-purposed tile Reused tires

Recycle  Recycling: the recovery of materials from waste  Yard clippings: made into different products for natural fertilizer  Trash: Recyclable materials: Plastics, paper, aluminum, wood, glass, cardboard Yard clippings into fertilizer

 Recycling Resources  Electricity is generated in waste-to-energy plants  Resource recovery: Use garbage to make electricity  Ex: companies make electricity using their own waste which saves money and conserves resources A waste-to-energy plant can provide electricity to many homes and businesses. About 16% of the solid waste in the United States is burned in waste-to-energy plants. But some people are concerned that these plants pollute the air. Other people worry that the plants reduce recycling.

Maintaining Biodiversity  Every species has a unique role in an ecosystem-- Losing one species could disrupt an entire ecosystem  Protecting Habitats  To protect the interconnected web of organisms, COMPLETE HABITATS, not just individual species, must be preserved.

Environmental Strategies  Laws have been passed to help protect the Earth’s environment. 1. Reduce pollution:  Recycle, don’t dump wastes 2. Reduce pesticide use  Use natural pesticides 3. Protect habitats  Conserve wetlands; Reduce deforestation 4. Develop alternative energy sources:  Increase use of renewable energy (solar and/or wind power) or biofuels