Which factor does NOT affect oxygen saturation in aquatic environments?

Oxygen saturation in aquatic environments is affected by several factors, each impacting how oxygen is dissolved and available in water. Temperature plays a significant role because warmer water holds less dissolved oxygen compared to cooler water. Atmospheric pressure also influences oxygen availability; at higher altitudes, the lower atmospheric pressure decreases the amount of oxygen that can be dissolved in water. The presence of aquatic plants is crucial since they produce oxygen through photosynthesis during daylight hours, affecting overall oxygen levels in the water.

Water salinity, while it influences the density and chemistry of the water, does not directly determine the amount of oxygen saturation. In fact, changes in salinity can have complex effects on aquatic organisms, but they do not influence the inherent capacity of water to hold oxygen in the same way that temperature or atmospheric pressure does. Thus, while salinity is an important factor in aquatic ecosystems, it does not directly correlate with oxygen saturation levels.