First off I would like to clarify one point in my last post. Oscillic refers to the movement of the water in terms of flow rate and retention time. Oscillic water is water that does not strictly behave like a river or like a lake but can behave like both, depending on the conditions. Therefore, the zone that I am looking at is an example of a oscillic freshwater zone but it is not the only example. The true name of the area in which my research is focused is the tidal freshwater zone.
I have made a lot of discoveries about the tidal freshwater zone in the past few weeks. First, I have determined that the further downstream you go, the less oxygen there is in the soil profile. This leads me to believe that there is a higher amount of cellular respiration occurring downstream on the river. Second, I have noticed higher oxygen penetration in the Aransas river than in the Mission river. My hypothesis is that the Aransas river has a faster flow rate which causes a lower retention time. I am still in the process of obtaining the data on the flow rate in both rivers. I have obtained most of my data for my presentation but I am still in the process of analyzing it so I cannot make any definitive statements about my findings yet. More to come soon.