With the exception of a few anaerobic bacteria, all life forms are dependent upon a source of oxygen gas.
Aquatic organisms aquire their oxygen dissolved in water.
The level of dissolved oxygen in the water can be an excellent indicator of the primary productivity of an aquatic habitat. Lower water tempertures, larger amounts of turbulence, shallower water, and increased photosynthetic activity by plants all contribute to an increase in DO levels. Higher temperatures, slower moving or deeper water, and increased rates of decomposition all contribute to lower DO levels. High dissolved oxygen levels supports greater diversity of organisms in aquatic systems. We use LaMotte's snap off DO viles and CBL's equipped with Vernier DO probes .