| Explore | Cadence- I have a garden at home where I grow a variety of plants such as potatoes, chives, rosemary, nasturtium, and oregano. I also have a cactus in my room named Mark. Most of my family gardens so I spend time helping my mom, grammie, and papa with their gardens at home. Ben- I like plants and trees. When I was young I tried planting apple seeds outside without soil, just dug a hole into the ground, put the seed in, covered it with dirt, and left it there, not even watering it Anthony- The best plant i have grown is green beans Owen- My mom owns a tower garden and she grows the best lettuce on the tower. We know that some seeds require different climates. And in those different climate there are different temperatures and different amounts of sun/water. We are interested in how different liquids other than water would affect plant growth. For example if we added lemon juice or another substance to the water will it affect the plant growth. |
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| Research Question | Does salt affect the the growth rate and height of a cress plant? Does salt affect seed germination of cress? |
| Predictions | We think that the plant will survive for some time with the salt. We think that some seeds will germinate but not all. With a ton of salt it might survive for a week but no longer. |
| Experimental Design | Materials -ten containers -200 cress seeds -5 cups of soil -5 Liters of water -50 grams of salt -5 Paper Towels -5 petri dishes -5 water container- Soda bottles? -5 graduated cylinders EXPERIMENTAL DESIGN Put soil in containers mix water Put 200 ml of water in soil Soak paper towels in water Place paper towels in petri dishes Plant seeds in soil Put some seeds in petri dishes Add 25-50 ml of salt water daily depending soil wetness and measure (Start with normal for pot plants until grown) |
| Conclusion | The data supported our prediction that the plants will survive for some time with some salt, maybe a week or so, and the plants with less salt would survive longer. It also supported our prediction that some seeds will germinate but not all. We can prove this with our healthy plants chart. One example in the healthy plants chart is that our twenty ppt B pot ( or the second pot that got the salt concentation of twenty ppt) had eight healthy plants on 10/18 and by the 25th there were 0 healthy plants. Another way we can prove this is by looking at 15 ppt B (or the second pot that got the salt concentration of 15 ppt). On the 19th, the average height was 2.82 cm, and on the 28th the average was 2.33 cm. Not all of the plants survived which changed our average height. This helps prove our point because if you look at one of our control pots, over the same period of time, the control plant grew .63 cm. Supporting Data: Concentration of Salt Average Ending Height (cm) Average # of Healthy Plants at End of Experiment Control 4.2 3.5 5 ppt 0.8125 2 10 ppt 2.75 0 15 ppt 4.05 0 20 ppt 4.115 0 The best way to prove we were correct in saying that some seeds will germinate but not all is to look at our germination graph. If you look at our germination graph you can see that all ten of the 0 ppt had sprouted and 8 ended up growing. On the other hand in our 10 ppt experiment only 1 had sprouted in the experiment but ended up dying. In this experiment especially you can see the line between the 5 ppt and the 10 ppt. In the 5 ppt all of them germinated and all of the spouts grew into plants, unlike the 10 ppt. At the end of this experiment, we ended up looking at all of the plants that had germinated and taking some more measurements. In doing this, we also found that the control is heavier per sprout. In the control, the average weight per sprout was 0.025 grams, and in the 5 ppt, the average weight per sprout was 0.01 grams. This is another interesting finding. Not only does salt affect the amount of germination, but it also affects the weight of the plants germinated. Supporting Data: Salt Concentration # Germinated at End of Experiment Average Mass Per Sprout at End of Experiment in Grams Control 8 0.025 5 ppt 10 0.01 10 ppt 0 N/A 15 ppt 0 N/A 20 ppt 0 N/A Although our experiment turned out okay, there were a few major experimental errors along the way. When one of our group members was bringing in some of the plants he was growing at home, another student accidentally knocked the plant out of his hands as he was walking past. Another issue we had was with the watering. We think that somewhere along the line one of our control plants got watered with the wrong water because it was looking droopy, like it had gotten watered with salt. We didn’t really have any unexpected results, other than a few mishaps when everything went as planned. An idea for a future experiment would be to find out if salt affects the mass of other germinated seeds that weren’t cress, such as buckwheat for example. One real world connection would be in the massive drought in California. All of their crops are failing because they have little to no freshwater. However, they do have lots of saltwater along the coast, so if you figured out how high the salt to water ppt ratio could be, then you could figure out a way to use the salt water to help fix that problem. Using all of that data you can conclude that cress plants can handle some salt, up to 5 ppt but no more. This would be about a seventh as salty as ocean water and not any where close to the amount of salt that would be in the snow and ice that has been salted for winter. |
| Investigation Theme | WOS |
| Teacher Name | Rebecca Buzzell |
| School Name | Nottingham School |
| Session | Fall 2021 |
| About this Project | The team had an excellent communication with the mentor about the the experiment process with updated journals, photos, and posts. They did a good job on analysing the data and making detailed conclusion on the experiment. |
