Dissolved Oxygen Content in Cedar Lake

In an aquatic system, there is a balance between the production and consumption of oxygen. Oxygen is produced by photosynthetic microorganisms, and is taken directly from the atmosphere; it is consumed by the respiration of aquatic animals, decomposers, and a myriad of other chemical reactions. The biochemical oxygen demand (BOD) is the amount of oxygen consumed by organisms and is measured as dissolved oxygen (DO). DO concentrations are dependent upon temperature, wind and other physical factors, fluctuating diurnally. In our experiment we will compare the DO concentrations at different depths in Cedar Lake. We will accomplish this by using a dissolved oxygen meter (YSI DO probe) to collect DO at depths of 1 foot intervals, starting from the surface of the water. We will also collect data on the temperature and wind speed at the same time to determine how they affect the DO concentrations at each depth, on each day. We expect to see higher levels of dissolved oxygen at the surface of the lake due to the closer proximity to the atmosphere and the churning effect of the wind. Although the water at the bottom would likely be colder, and therefore hold more oxygen, it is also being consumed by decomposers