Discussion

Our research investigated questions about how the environment changes during the fall, how tree leaves change, and if the same thing happens at both schools. We definitely found differences in the timing of the color change and decided that could be the influence of being near a large body of water. We found changes in leaf reflectance that we could explain (for example, the blue wavelength increased as chlorophyll disappeared from the leaf), and other changes that we could not explain (why Indiana's green wavelength reflectance did not change during autumn?). What we really learned was how the tree is connected to its environment. We became more aware of how a leaf is alive, and how it creates its own food by photosynthesizing. The neat thing about this research was that simply measuring the light reflectance could monitor the life of a leaf. In Europe, scientists say warmer temperatures are affecting the spring and autumn seasons. This is affecting the growth patterns of plants and delaying the flight of birds from one place to another. There are connections between the seasons and climate change. Our leaf study found connections between living things, the environment, and the season. We suspect the warmer the air is, the more delayed the changes of the leaves will be. Anthocyanins thrive in cool, crisp air, and when it is warm, they take longer to appear. We felt our project was a success because we were able to learn how to measure changes and differences in the environment, and in the leaves. It was great to compare the results from our two schools. We compared our climate differences, like how ISD is further inland while MSSD is closer to Chesapeake Bay and the Atlantic Ocean. This experiment enabled us to understand what we read in our science textbooks. We experienced a "real science" project and we probably would not have been able to get this experience anywhere else. It was wonderful exchanging information with each other by videoconference. It was an enriching experience to communicate through a camera and a television. We were able to show each other data, graphs, information, and sign all of our questions the way we wanted it to be! We learned that we would get better results if we checked equipment to see if it's in working order, every time we went out. The data probably will be more accurate if we measure more often during the week. We should do leaf reflectance measurements two times a year, in the autumn and in the spring. We could compare results from autumn measurements and spring measurements. If we gathered more years of measurements, maybe we could see the climate changes over the years. Some problems we encountered were the infrared-1 lights breaking on MSSD's ALTA Spectrometer and the tree we were analyzing was probably too close to the building. The green wavelength dropped to 0.00%, which should never happen, and might be due to equipment problems. It was hard to have a videoconference because the only time we could do it was during the other school's hours and our time zones and schedules were different. We have ideas for further research. From reading GLOBE's Green Down protocol, we know that the greenness of the leaves could be related to the amount of carbon dioxide in the air, since plants remove the carbon dioxide during photosynthesis. We are wondering how much the carbon dioxide changes around our tree from before the leaves change color until after they change color. We'd like to measure the carbon dioxide and see how it changes during the fall. Also, we learned that during photosynthesis, plants release water because of transpiration. We are wondering what happens to that water in the environment during autumn. Does our tree affect the humidity? We were thinking about how the air temperature affects the color change of the tree's leaves. Does the tree have any effect on the air temperature? We obviously have enough questions to continue this research at both of our schools for several years!