How does salinity affect the freezing point of inland water?

In inland water ecosystems, salinity plays a critical role in determining the physical properties of water, including its freezing point. The presence of dissolved salts, such as sodium chloride, lowers the freezing point of water through a process known as freezing point depression.123

Essentially, dissolved salts act as solutes that interfere with the ability of water molecules to bond together into a rigid, solid structure. As the concentration of these ions increases, it becomes progressively more difficult for the water to transition into ice at the standard freezing temperature of 0 °C (32 °F).32

In addition to lowering the freezing point, higher salinity also reduces the temperature of maximum density in water. These physicochemical changes are significant because they distinguish saline lakes from freshwater bodies, influencing the thermal structure and overall biological environment of the ecosystem.21