User: | Open Learning Faculty Member:
When I initially planned this experiment I thought I would be able to determine different shades of green present on the trees. I had planned to match the tree trunks to a color wheel and see different shades of green. After making my first few attempts at data collection I quickly realized that this method would not work. Different viewing angles changed the lighting on the trunk and that alone changed the color. It was also difficult to determine different shades depending on what was around the tree or even in the background. I decided this method was too subjective and changed from my continuous approach to a categorical one to make observations just on the presence or absence of green on the tree trunks. Some of the data I collected did surprise me. I did not expect to see green all the way around the trunk on some trees. I also didn’t expect to see it completely absent on others. I plan to continue to collect data based on the presence or absence of color. I feel it is the best method I have without access to more expensive and accurate ways of measuring the green layer. Ideally I would be able to cut out small samples of bark and measure the thickness of the chlorophyll layer to get a truly accurate measurement as well as see if it was present in the areas where it wasn’t visible to the human eye.
My response as per Module 5:
Good catch on the variation in green of the trunk. It would be hard to subjectively detect the difference unless you had access to equipment to do the detection. Color gradient detection even varies among individual observers, especially under changing light conditions outside.
I like the idea of samples with thickness measurement. You could do a lot of sampling quickly with this and would allow your hypothesis (as seen in blogpost 3) to be falsifiable or proven.
One small adjustment to your hypothesis may improve the resolution of your results; you mention ‘green pigment’ and that could be clarified further in your hypothesis in order to determine where it comes from so you can exclude any other factors that may cause this (such as other flora).