Acid Rain Lab
Collaborators:
AP Environmental Science 1st Period Class
Abstract:
In order to test the effects of acid rain on vegetation, an experiment was conducted. The experiment involved watering samples of grass with solutions with pH levels of 2, 4, and 6 over an extended time period. It was discovered that the grass watered with more acidic water did not grow as tall, was discolored, and was not standing up straight. Furthermore, these effects become progressively visible as the acidity increases.
Problem:
According to EPA.gov, "acid rain is a serious environmental problem that affects large parts of the United States and Canada... [It] is particularly damaging to lakes, streams, and forests and the plants and animals that live in these ecosystems." What are the specific effects of acid rain on grass?
Hypothesis:
If groups of grass are watered with different pH levels, then it will be found that the grass watered with the lowest pH will grow as much less in terms of height and become discolored.
Parts of the Experiment:
Independent variable is the level of acidity of the water poured on the grass while the dependent variable is the characteristics of the grass such as height, color, health of roots, etc. Experimental group is the grass which received the acid water while the control group was the grass that was just watered with distilled water.
Materials:
Six 2 liter bottles, scissors or a knife, potting soil, grass seed, water, sulfuric acid, sunlight
Methods:
1. Cut six 2 liter bottles in half.
2. Place soil in the bottles.
3. Spread grass seed through one of the bottles' soil.
4. Water the seed every 3-4 days (with regular water) and make sure the bottle is under light. Do this until the grass grows 2-4 inches tall.
5. Now, separate the bottles into three groups, two in each group.
6. Create three different solutions of water: one simply distilled, one with a pH of 4, and the other with a pH of 2.
7. Water each different group with an assigned solution about two or three times a week for about three weeks.
Data:
Collaborators:
AP Environmental Science 1st Period Class
Abstract:
In order to test the effects of acid rain on vegetation, an experiment was conducted. The experiment involved watering samples of grass with solutions with pH levels of 2, 4, and 6 over an extended time period. It was discovered that the grass watered with more acidic water did not grow as tall, was discolored, and was not standing up straight. Furthermore, these effects become progressively visible as the acidity increases.
Problem:
According to EPA.gov, "acid rain is a serious environmental problem that affects large parts of the United States and Canada... [It] is particularly damaging to lakes, streams, and forests and the plants and animals that live in these ecosystems." What are the specific effects of acid rain on grass?
Hypothesis:
If groups of grass are watered with different pH levels, then it will be found that the grass watered with the lowest pH will grow as much less in terms of height and become discolored.
Parts of the Experiment:
Independent variable is the level of acidity of the water poured on the grass while the dependent variable is the characteristics of the grass such as height, color, health of roots, etc. Experimental group is the grass which received the acid water while the control group was the grass that was just watered with distilled water.
Materials:
Six 2 liter bottles, scissors or a knife, potting soil, grass seed, water, sulfuric acid, sunlight
Methods:
1. Cut six 2 liter bottles in half.
2. Place soil in the bottles.
3. Spread grass seed through one of the bottles' soil.
4. Water the seed every 3-4 days (with regular water) and make sure the bottle is under light. Do this until the grass grows 2-4 inches tall.
5. Now, separate the bottles into three groups, two in each group.
6. Create three different solutions of water: one simply distilled, one with a pH of 4, and the other with a pH of 2.
7. Water each different group with an assigned solution about two or three times a week for about three weeks.
Data:
Data Analysis:
The grass is much shorter in the bottles which received the acidic water, especially in the one with the pH of 2. Also, by looking at the bottom of these bottles, it was seen that there were less roots as well. Furthermore, the color of the grass differs across the different bottles; the grass in the one watered with the normal water is bright green and becomes progressively darker as the acidity of the water increases. Another interesting discovery is the strength of the grass. To explain, it seems that the grass watered with the 2 and 4 pH solutions is not standing as tall as the one with distilled water. This is especially true of the water with a pH of 2.
Conclusion:
The data affirms the hypothesis that watering the grass with an acidic solution will cause it to not grow as much and become discolored. Despite this, a little more discoloration was predicted than just a slight change in the shade of green. Also, the way the grass in the more acidic solutions is scattered in all directions and not standing straight up was not predicted. Still, this does not invalidate the hypothesis, it is merely adds on to it. The data gathered also confirms the original point of doing the experiment - it can be proven that acid rain negatively affects vegetation.
If this experiment were to be repeated, there are definitely several things that could be done to improve it. First of all, the watering of the grass and the amounts given could be more precise. To elaborate, there was some incident regarding an excess of one of the solutions being lost somewhere (presumably poured in one of the bottles). This could have negatively affected the results. Another thing that could have been done to improve the experiment would be increasing the sample size (using more bottles), as this would generate more accurate results.
Citation:
"Acid Rain." EPA. Environmental Protection Agency, n.d. Web. 11 Dec. 2013. <http://www.epa.gov/acidrain/>.
The grass is much shorter in the bottles which received the acidic water, especially in the one with the pH of 2. Also, by looking at the bottom of these bottles, it was seen that there were less roots as well. Furthermore, the color of the grass differs across the different bottles; the grass in the one watered with the normal water is bright green and becomes progressively darker as the acidity of the water increases. Another interesting discovery is the strength of the grass. To explain, it seems that the grass watered with the 2 and 4 pH solutions is not standing as tall as the one with distilled water. This is especially true of the water with a pH of 2.
Conclusion:
The data affirms the hypothesis that watering the grass with an acidic solution will cause it to not grow as much and become discolored. Despite this, a little more discoloration was predicted than just a slight change in the shade of green. Also, the way the grass in the more acidic solutions is scattered in all directions and not standing straight up was not predicted. Still, this does not invalidate the hypothesis, it is merely adds on to it. The data gathered also confirms the original point of doing the experiment - it can be proven that acid rain negatively affects vegetation.
If this experiment were to be repeated, there are definitely several things that could be done to improve it. First of all, the watering of the grass and the amounts given could be more precise. To elaborate, there was some incident regarding an excess of one of the solutions being lost somewhere (presumably poured in one of the bottles). This could have negatively affected the results. Another thing that could have been done to improve the experiment would be increasing the sample size (using more bottles), as this would generate more accurate results.
Citation:
"Acid Rain." EPA. Environmental Protection Agency, n.d. Web. 11 Dec. 2013. <http://www.epa.gov/acidrain/>.