LAB Growing Grass in Acid Rain Science 6 Pollution

Background Information Acid rain is rarely acidic enough to kill trees and other plant life directly. The effect of the acid rain is to weaken the plant making it more vulnerable to insects, diseases, and storm damage.

Acid Rain’s Effect on Trees

Why is Acid Rain Harmful? Acidic water dissolves the nutrients and helpful minerals in the soil and then washes them away before trees and other plants can use them to grow. (phosphorus, potassium, calcium and magnesium)

Why is Acid Rain Harmful? At the same time, acid rain causes the release of substances that are toxic to trees and plants, such as aluminum (<5.5) and other metals, into the soil. (zinc, manganese, copper and iron)

Effect of Acid Rain

Origin of Acid Rain Sulfur dioxide (SO 2 ) and nitrogen oxides (NOx) are the primary causes of acid rain. SO 2 in US –2/3 comes from electric power plants burning fossil fuels like coal. Nitrogen oxides –1/2 come from cars and trucks burning gasoline. –¼ electric power plants burning fossil fuels like coal. Acid rain occurs when these gases react in the atmosphere with water, oxygen, and other chemicals to form various acidic materials. The result is a mild solution of sulfuric acid and nitric acid rain or snow.

Information A natural chemical reaction with carbon dioxide in the air turns neutral water slightly acidic. Rain water can have a pH of 5.6.

Fresh Water Habitats The pH of most lakes and ponds is between 6 and 8. In fresh water, crustaceans, mollusks, and snails begin to die when the pH drops to slightly under 6.0.

Fresh Water Habitats The young of most species are more sensitive than adults. Frogs may tolerate relatively high levels of acidity, but if they eat insects like the mayfly, they may be affected because part of their food supply may disappear. Some acid lakes have no fish. At pH 5, most fish eggs cannot hatch. At lower pH levels, some adult fish die. Toxic substances like aluminum that wash into the water from the soil may also kill fish.

Level of Plant Tolerance

Video EPA video: Effects of Acid Rain

pH of Tested Water Samples (Information) Most plants do best in slightly acidic soils between 6.0 and 7.0. Type of WaterpH Level Tap Water ½ & ½ Water Acid Water Vinegar

LAB: Growing a Grass Garden Jobs Rotate jobs in your group: –Materials –Encourager –Recorder –Timekeeper –Reader

Problem How will water of 3 different pH levels affect the growth of grass? What qualities of the grass should we look for when we observe the grass? –height –color –volume –sturdiness –soil –roots

Information What do you already know about grass? What did you just learn about the effect on plants of water with an acidic pH level?

Hypothesis Which of the three gardens do you think will grow the best? Explain why. Which of the three gardens do you believe will have the worst growth? Explain why. If….then….because…...

Hypothesis(Educated Guess) If the water used on the grass garden has a pH < 5.5, then the grass will not be as tall, green, as many blades or as sturdy because… __________________________________ I believe the grass garden watered with the ______ water will grow the best because… I believe the grass garden watered with the ____ water will grow the worst because…

LAB #10 Procedure M 1 : Fill fluted container with ½ of bag of soil. (about 2 cups) E: Sprinkle the packet of seeds on top of the soil. T: Cover seeds with 1 cm (3/8 in) soil. Rc: Write period, name, and type of water on masking tape to label. Adhere to front of container. Rd: Read the steps IN ORDER for your team to follow.

Procedure M : Get 100 ml of the correct type of water you need for your team’s grass garden: –Tap water –½ and ½ water- –Acid water T Carefully pour the100 ml water on your grass garden. Try to spread it out evenly.

Clean-Up T - wipe off table, trash and recycle Rc – grass gardens to teacher when requested M - return bins to LAB table E – Return goggles

Follow Up On Monday (10/6), Wednesday (10/8), Friday (10/10), and Monday (10/13), we will observe and measure any growth that has occurred. Students will write careful observations on their LAB sheet. Then you will water the gardens.

DATA: Period 1 Height Grass Garden Day 4 10/6 Day 6 10/8 Day 8 10/10 Day 11 10/13 Tap Water Roots 1 cm 2cm 3 cm R – 2cm 7cm 8 cm 3 cm 10 cm 11 cm R 3 cm ½ and ½ Water Roots.25 cm 1.5cm 2.5 cm R – 1.5 cm 5 cm R – 2 cm 5.5 cm R – 3.5 cm 8 cm R – 2.5 cm 8.5 cm R – 6 cm Acid Water Roots.5 cm 1 cm 1.5 cm R – 2 cm 1.5 cm R – 2 cm 3.5 cm R – 3.5 cm R – 3 cm 7 cm R 4.5 cm 5 cm R cm

DATA: Period 2 Height Grass Garden Day 4 10/6 Day 6 10/8 Day 8 10/10 Day 11 10/13 Tap Water 2 mm R-.5cm R – 1.5cm 3 cm 10 cm 2.5 cm R – 3.5 cm 7.5 cm R – 13 cm 7 cm R – 10 cm 12.5 cm R – 17 cm 14cm R – 7 cm ½ and ½ Water R- 2cm R- 1 cm 2.5 cm R – 6 cm 1.5 cm 3.5 cm 6 cm R – cm 5 cm R – 2 cm 8.5 cm R – 12 cm 5 cm R – 8 cm Acid Water 4 mm R- 5mm R -.75 cm 1.5 cm R – cm R – 2 cm 2.5cm R – 5.5 cm 2.5 cm R – 2 cm 4.5 cm R – 2.5 cm 6.5 cm R – 5 cm

Data: Period 5 Height Grass Garden Day 4 10/6 Day 6 10/8 Day 8 10/10 Day 11 10/13 Tap Water pH 6.5 R- 1.5 mm 2 mm R - 1 cm 3.5 cm 5.5 cm R- 6 cm 8 cm R – 7cm 11cm R – 7 cm 17 cm R - 10 cm 19 cm R – 9 cm ½ and ½ Water pH 5 5 mm R - 1 cm R – 6 mm 3.5 cm R – 4 cm 2.4 cm R - 4 cm 8cm R – 4 cm 9.2cm R – 4.5 cm 13 cm R – 13.5 cm 13 cm R –cm Acid Water pH 4 R – 1 cm R - 5 mm 1.5 cm R- 2.5 cm 2 cm R – 6 cm 7cm R – 8 cm 5 cm R cm 7 cm R – 9 cm 11 cm R – 10.5 cm

DATA: Period 7 Height Grass Garden Day 4 10/6 Day 6 10/8 Day 8 10/10 Day 11 10/13 Tap Water pH 6.5 R – 1 cm 1 mm R cm 3 cm R – 3 cm 8cm R – 10 cm 6 cm R – 9 cm 13 cm R – 14 cm 12 cm R – 15 cm ½ and ½ Water pH 5 R -.5 cm R – 4mm 2.75 cm R – 5 cm 3 cm R – 4.5 cm 5.5 cm R – 5 cm 6 cm R – 5 cm 10 cm R – 8 cm 10 cm R – 7 cm Acid Water pH 4 R – 1 cm 2.5 cm R – 2 cm 2.5 cm R – 5 cm 4.5 cm R – 6 cm 4.5 cm R – 5.5 cm 9 cm R - 14 cm 7.5 cm R – 8 cm

Clean - up E: wipe out bin R: wipe off table T: carry garden to windowsill M 2: return beaker and masking tape to bin M 1: return bin to table

Written Observation Type of Water _____________ Day 4 colorNo grass volumeSeeds scattered over the surface sturdinessStraight soildry, cracked surfaced, minute white crusty objects spread on top of soil roots 5 roots visible only through the bottom, white, fuzzy root hairs attached to the roots Day 6 color volume sturdiness soil roots

Written Observation Type of Water _____________ Day 4 color volume sturdiness soil roots Day 6 color volume sturdiness soil roots

Written Observation Type of Water _____________ Day 4 color volume sturdiness soil roots Day 6 color volume sturdiness soil roots

Written Observation Type of Water _____________ Day 8 color volume sturdiness soil roots Day 11 color volume sturdiness soil roots

Written Observation Type of Water _____________ Day 8 color volume sturdiness soil roots Day 11 color volume sturdiness soil roots

Written Observation Type of Water _____________ Day 8 color volume sturdiness soil roots Day 11 color volume sturdiness soil roots

Grass Garden Conclusion #1 Do you accept or reject your hypothesis? WHY? I accept (or reject) my hypothesis because

Grass Garden Conclusion #2 Do you see a difference between the gardens that are watered with different pH water? What do you see? What relationship is there between the pH of water and the growth of the grass?

Conclusion Do you have any questions? What makes you curious? Were there any errors? Explain

RACER