How Do People use Earth’s Resource? Land, Air, and Water Resources Ms. De Los Rios 7th Grade 8-4 Water Pollution and Solutions Essential Question: How Do People use Earth’s Resource? Why is Fresh Water a Limited Source? What are the Major Sources of Water Pollution? How can Water Pollution Be Reduced? Pgs. 280-287

Vocabulary Pesticide- A chemical that kills insects and other crop-destroying organisms. Sewage- The water and human wastes that are washed down sinks, toilets, and showers. Sediment- small, solid pieces of material that come from rocks or the remains of organisms; earth materials deposited by erosion.

My Planet Diary- pg. 280 A Flood of Sludge In December 2008, over 4.5 billion liters of polluted water flooded the area around Kingston, Tennessee. A nearby coal-powered electric plant produced polluted water containing arsenic, lead, and other toxic chemicals. The toxic chemicals and coal ash mixed with water in a holding pond to form a thick sludge. When the dam holding back the pond broke, the water poured into rivers. The sludge water spilled over the land, damaging trees, homes, and other buildings. Local residents feared the flood would be dangerous to their health as well. Communicate- Is water pollution a problem in your community? Why or why not? ____________________________________________ _______________________________________________________

Why Is Fresh Water a Limited Resource? Pg. 280 Oceans cover nearly three fourths of the Earth’s surface. Yet water is scarce on Earth because most of it—about 97 percent—is salt water. Salt water cannot be used for drinking or watering crops. About three quarters of the planet’s fresh water is ice. For drinking water, people use fresh liquid water and groundwater, which is water stored in soil and rock beneath Earth’s surface. Water is renewable: It cycles between the atmosphere and Earth’s surface. Water shortages occur when people in an area use water faster than the water cycle can replace it.

Assess Your Understanding pg. 281 I get it! Now I know that fresh water is limited on Earth because_______________________________________________________________________________________________

What are the Major Sources of Water Pollution? Pg. 282 Since fresh water is scarce, water pollution can be devastating. Most water pollution is the result of human activities. Wastes produced by agriculture, households, industry, mining, and other human activities can end up in water. AGRICULTURAL WASTE Agricultural wastes include animal wastes, fertilizers, and pesticides, chemicals that kill crop-destroying organisms. HOUSEHOLD SEWAGE The water and human wastes that are washed down sinks, showers, and toilets are called sewage. Sewage must be treated to kill disease-causing organisms.

This scene may show common things found on a farm, Farm Pollution This scene may show common things found on a farm, but even common things can lead to water pollution. Circle the potential sources of water pollution.

What are the Major Sources of Water Pollution? Pg. 282 INDUSTRY AND MINING WASTES Industries and mines produce chemicals and metal wastes that pollute water. HEAT Some factories and power plants also produce thermal pollution, releasing heated water that can kill organisms living in bodies of water. OIL AND GASOLINE Spills and leaks of oil and gasoline can cause catastrophic damage to living things in water. SEDIMENTS Water that causes erosion picks up sediments, or particles of rock and sand. In bodies of water, sediments can prevent plants from growing by blocking sunlight.

Water Pollution Sources What are the various causes of water pollution? Fill in the graphic organizer below to outline causes of water pollution.

Assess Your Understanding pg. 253 I get it! Now I know that the major sources of water pollution include _____________________________________________ ___________________________________________________

How Can Water Pollution Be Reduced? Pg. 284 By working together, governments, industries, and individuals can improve water quality. The keys to keeping water clean are effective cleanup of oil and gasoline spills, proper sewage treatment, and reduction of pollutants. Cleaning Up Oil and Gasoline Spills While natural bacteria can clean up small amounts of oil in bodies of water, it is necessary for people to help clean up large spills. Gasoline or oil leaks from underground tanks is hard to clean up.

Wastewater Treatment pg. 284 There are several steps to proper sewage treatment. What is the correct order of proper sewage treatment steps?

How Can Water Pollution Be Reduced? Pg. 284 Sewage Treatment In most communities, wastewater and sewage are treated before they are returned to the environment. Reducing Pollutants Many industrial companies are trying to reduce the amount of waste they produce, as well as to recycle wastes. What You Can Do Individuals can take steps at home to avoid creating water pollution.

Analyze Costs and Benefits pg. 285 What are the pros and cons of using bacteria to clean oil spills? 1.Fill in the boxes with some pros and cons of using engineered bacteria to clean oil spills. 2. If you were creating bacteria for cleaning oil spills, what characteristics would you want to test the bacteria for? __________________________________________________________________ __________________________________________________________________

Fig. 4 How do people use Earth’s Resources? Pg. 286 All living things depend on land, air, and water. Conserving these resources for the future is important. Part of resources for the future is important. Part of resource conservation is identifying and limiting sources of pollution. Land- Identify one impact humans have had on land. Then describe one way to reduce pollution on land. ____________________________________________________________________________________________________________ Air- Identify one impact humans have had on the air. Then describe one way to reduce air pollution. Water- Identify one impact humans have had on water. Then describe one way to reduce water pollution.

Assess Your Understanding pg. 286 1a. What are sediments? _________________________________ ______________________________________________________ b. How can bacteria help clean an oil spill in the ocean? _________ c. How do people sue Earth’s resources? ____________________ _____________________________________________________ d. Why might a company not want to recycle the waste they produce even if it would reduce water pollution?________________ I get it! Now I know that water pollution can be reduced by ______