The Science of Maryland Agriculture

Transcription

1 Edition 3 (2016) The Science of Maryland Agriculture GOAL STATEMENT: Students will develop an understanding of ways in which human activities can cause nonpoint pollution within a watershed. OBJECTIVES: Students will create a landscape model and add residential, business, and agricultural development areas. Students will add nonpoint source pollutants to their model and observe the effects of precipitation on pollutants. Students will identify possible effects of nonpoint pollutants within the Chesapeake Bay watershed and research strategies to reduce nonpoint pollution. REQUIRED MATERIALS: Chesapeake Bay Watershed Map Activity Directions worksheet (1 per group) Analysis and Conclusion Questions worksheet (1 per student) Aluminum foil 6 feet of standard foil or 3 feet of heavy duty foil (per group) Plastic tub about 12 x 18 x 6 deep (1 per group) Permanent markers blue and other colors Development icons Scissors Transparent tape or double-sided tape Pollutant substances (1 set per class) 14 small jars or beakers Icons for labeling pollutants Ingredients to make pollutants see teacher s key for suggestions Small spoons or forceps for solid pollutants Small droppers for liquid pollutants Small spray bottles (1 per group) AMOUNT OF TIME TO ALLOW: 70 minutes. Extension activities will take additional time.

2 Most people think the main factor that influences water quality is point source pollution, which is single-source pollution from a major disaster like an oil tanker spill or oil well leak. However, nonpoint pollution contributes the vast majority of pollutants that enter bodies of water in a typical year. Nonpoint pollution is the sum of small amounts of pollutants from numerous sources. Small amounts of pollutants scattered over a watershed can move downstream or through groundwater and end up concentrated in one area. Nonpoint pollutants can include topsoil, plant matter, fertilizer, solid waste or trash, herbicides and pesticides, industrial air pollutants, animal waste, soaps or detergents, antifreeze, leaking sewage, acid rain, motor oil, and others. These pollutants can be transported by rain, wind, and gravity. Everyone contributes to nonpoint pollution. Homeowners contribute to pollution when their cars leak oil onto the ground, when their septic or sewage system fails, or when they over-apply fertilizers and lawn chemicals. Developers contribute to pollution when they improperly protect loosened soil from erosion or when they create paved surfaces such as parking lots that allow pollutants to run off during rain. Farmers contribute to pollution when they over-apply agricultural chemicals or mismanage topsoil and accidentally accelerate rates of soil erosion. Farmers, developers, and homeowners play a key role in protecting and preserving the Chesapeake Bay. Maryland environmental regulations require the use of conservation techniques and/or best management practices (BMPs) that minimize environmental damage. These strategies help to reduce soil erosion and improve water quality. In the Conservation Choices lesson, another lesson in this curriculum, students will explore and apply a wide variety of conservation techniques. It is important that everyone makes efforts in their daily life to minimize the amount of pollutants that they contribute to the environment. This lesson will help students understand the sources of nonpoint pollution and what they can do to reduce nonpoint pollution. 10 minutes Ask students what they already know about the Chesapeake Bay watershed. Discuss ideas. Show students a map of the Chesapeake Bay watershed that highlights the parts of each state New York, Pennsylvania, Maryland, Delaware, Virginia, West Virginia, and D.C. Explain that the Chesapeake Bay watershed covers an area of 64,000 square miles. More than 17 million people live in the watershed, and our actions can have positive or negative effects on the Bay s water quality.

3 30 minutes 1. Divide students into small groups. Distribute copies of the activity instructions and analysis and conclusion questions worksheets. 2. Provide each group with a plastic tub, a piece of foil, and a blue permanent marker. Explain that students will use the foil to create a landscape inside the pan. (Heavy duty foil works best; if using standard foil, fold a larger piece in half to double the thickness.) Students should then use their blue markers to draw in all possible rivers, lakes, ponds, and streams. 3. Distribute scissors, tape, and printouts of the development icons. Explain that students will develop the land by taping the icons to the foil. Students may also use permanent markers to draw additional development features. Instruct students to carefully consider where to place different features based on topography, accessibility, and other characteristics of the land. 4. Ask students to consider what types of pollutants may be found in different areas of their models. Allow time for students to pollute their landscapes using the substances the teacher has prepared. Students need not use all pollutants, just those that make sense based on the development in their models. 5. Provide each group with a spray bottle of water. Explain that students will rain on their landscapes by spraying water over the model. Instruct students to observe the flow of water and movement of pollutants. 6. Have students complete the analysis and conclusion questions on their worksheets. 30 minutes Have each group show its model to the class and describe: (1) the topography (shape) of the landscape the group designed; (2) the group s land development technique; and (3) how the water and pollutants moved and whether they ended up in different watersheds. Use the questions from the activity to guide a class discussion. What effects did rainfall have on the different areas in your model? What happened to the different types of pollutants? Did the same thing happen to all of the pollutants? How does this model compare to real life? Explain that this activity demonstrates the problem of nonpoint source pollutants that enter watersheds and can eventually end up in the Chesapeake Bay or other bodies of water. Ask students why the pollutants they used in this activity are called nonpoint pollutants. Guide discussion to the concept that rain, wind, and gravity can transport pollutants in small amounts from all over the watershed. Nonpoint pollution is difficult to control because it comes from many different places.

4 Most people think that the main factor influencing water quality is point source pollution, singlesource pollution from major disasters such as the Exxon Valdez tanker oil spill or the Gulf of Mexico oil well leak. Actually, the opposite is true: each year, nonpoint source pollutants in the United States are by far the major sources of pollution to bodies of water. Small amounts of pollutants scattered over the Chesapeake Bay s 64,000 square mile watershed can all end up concentrated in the Bay and dramatically alter water quality. Emphasize that everyone must be careful in his or her daily life to minimize the amount of pollutants they contribute to the environment. Assign each group one or more of the pollutants used in the activity. Have groups research the sources of the pollutants, possible effects of the pollutants, and techniques to reduce pollutant entry into waterways. The Chesapeake Bay Foundation ( and the Environmental Protection Agency ( are good sources of information. As a class, compile a list of simple things everyone can do to reduce pollution. Format the list nicely and distribute it to students to take home and share with their families. On a weekly or monthly basis, check in with students to see if they and their families are following the pollution-reduction strategies. Which strategies are easy to follow? Which are difficult to follow? Stream monitoring and stream cleanup are excellent service learning projects. Find out if there are local environmental or watershed groups in your area that welcome volunteers for this kind of project. Your local Extension 4-H educator may be able to help you find opportunities in your area.

5 There are many careers associated with water quality. Water Quality Specialist This person tests samples of water for pollutants. Environmental Health Inspector This person goes to various locations and looks for signs of damage due to pollution. They notify property owners of violations and report violations to state agencies. Aquatic Biologist This person studies the effects of pollutants on animals and plants. Other careers are important for water quality even if we don t normally associate them with the Bay. Waste Management Specialist This person designs landfills and develops processes for collecting and disposing of solid waste (trash) so that it does not harm waterways. Sewage Treatment Specialist This person develops processes for treatment of sewage and reducing the amount of pollution from sewage that enters waterways. Nutrient Management Specialists This person develops plans for farmers that help reduce pollution from agricultural practices. Student understanding can be evaluated through class discussion or assessment of completed activity data sheets. The following questions may also be used to evaluate student learning. 1. What is the difference between point source and nonpoint source pollution? 2. What effects might nonpoint source pollution have on the environment? 3. Where does nonpoint source pollution come from? How can we prevent it? Chesapeake Bay Foundation, < Environmental Protection Agency, < EPA Water Quality Careers, <water.epa.gov/aboutow/careers/>. Chesapeake Bay Health Report Card, <ian.umces.edu/ecocheck/report-cards/chesapeake-bay/ >.

6 Teacher Key The following substances may be used to create pollutants for the activity. Pollutants (dry) Topsoil Plant Matter Farm Fertilizer Lawn Fertilizer Solid Waste (Trash) Pesticide Industrial Air Pollutants Substance Used in Model Dry powdered soil Crushed dried leaves Corn starch or baking soda Corn starch or baking soda Tiny pieces of shredded paper or foam Cinnamon or paprika Pepper Pollutants (wet) Animal Waste Soaps And Detergents Antifreeze Leaking Sewage Acid Rain (from auto exhaust and factories) Motor Oil Substance Used in Model Muddy water, coffee, or tea Diluted dish detergent Green colored water or Gatorade Colored water with corn starch added Vinegar Cooking oil or corn syrup The Science of Maryland Agriculture because of race, age, sex, color, sexual orientation, physical or mental disability, religion, ancestry,

7 Name: Date: Period: Activity Directions Background A watershed is the entire area of land from which water drains into a body of water such as the Chesapeake Bay. If you imagine a shed with a peaked roof, each side of the roof represents a different watershed because it sends water in a different direction. The Chesapeake Bay Watershed is very large, covering thousands of square miles. Water entering the Bay originates in six states and Washington, DC! Nonpoint pollution contributes the vast majority of pollutants that enter bodies of water, including the Bay. Nonpoint pollutants can include topsoil, fertilizer, trash, pesticides, air pollutants, detergents, antifreeze, leaking sewage, motor oil, and others. These pollutants can be transported by rain, wind, and gravity. Small amounts of pollutants scattered over the Chesapeake Bay s 64,000 square mile watershed can all end up concentrated in the Bay and dramatically alter water quality. Directions 1. Create a landscape. Use a sheet of heavy-duty aluminum foil or a double layer of thin foil to create a landscape with mountains, hills, and valleys, rivers and lakes, and/or flat land. Make sure your landform fits entirely inside the plastic pan. Use a permanent marker to draw in rivers, steams, lakes and ponds. How many different watersheds do you think your landform contains? How do you know? 2. Develop the land. Cut out the small icons and tape them to your model in areas that you decide are appropriate. You may also use permanent marker to draw other development features like schools, hospitals, or landfills. Carefully consider where to place the icons based on topography, accessibility, and other features of your landscape. 3. Pollute the land. Add small amounts of pollutants to the places on your model where they might be found in real life. Here are some ideas. Housing developments Pollutants may include lawn fertilizers, herbicides, and other substances used in and around homes. Businesses and parking lots Pollutants may include oil and other chemicals that may leak from cars onto the pavement. Farms Pollutants may include fertilizers and pesticides, manure, and soil eroding from fields. 4. Observe the movement of pollutants. Using a spray bottle filled with water, gently rain over your landscape for about one minute. Observe what happens to the pollutants. 5. Clean up and reflect. Listen to your teacher s directions about how to clean up your model. Then answer the questions on your worksheet. The Science of Maryland Agriculture because of race, age, sex, color, sexual orientation, physical or mental disability, religion, ancestry,

8 Name: Date: Period: Analysis and Conclusion Questions CREATING A LANDSCAPE WITH WATERSHEDS How many watersheds does your landscape have? How do you know? DEVELOPING THE LAND What strategies did your group use while planning the development? Did everyone agree? Why or why not? OBSERVING THE MOVEMENT OF POLLUTANTS Describe what you observed during a rainfall. ANALYSIS AND CONCLUSION QUESTIONS 1. What effects did rainfall have on the different areas in your model? 2. What happened to the different types of pollutants? Did the same thing happen to all of them? 3. This activity demonstrates the problem of NONPOINT POLLUTANTS that enter watersheds and can eventually end up in the Chesapeake Bay. Why do you think they are called nonpoint pollutants? 4. What kinds of short-term problems might be caused by pollutants entering the Bay? Long-term problems? 5. What are some things people could do to reduce the volume of pollutants that end up in the Bay? The Science of Maryland Agriculture because of race, age, sex, color, sexual orientation, physical or mental disability, religion, ancestry,