Is Lake Superior Freshwater Or Saltwater?
Lake Superior is the world’s largest freshwater lake, covering an area of approximately 82,414 square kilometers or 31,700 square miles. Its surface area is the second largest in the world, surpassed only by Lake Michigan-Huron. Its maximum depth of 406 meters / 1,332 feet makes it the deepeset of the North American Great Lakes. As a result, its volume of over 12,000 cubic kilometers / 2,900 cubic miles is the largest by far.
Lake Superior is known as a freshwater lake because of its high concentration of dissolved organic matter and low concentrations of dissolved salts. This low salinity level is due to nearly 40% of the lake being fed by thousands of rivers, creeks and streams. This water is typically low in salinity, coming from land-based sources such as rainfall, snowmelt and runoff from surrounding watersheds.
However, Lake Superior does contain some saltwater. The lake is connected to the Atlantic Ocean via the ST Lawrence River, which allows salt water to flow in from the Atlantic and mixes with the freshwater. This causes the salinity level of the lake to rise to an average of 0.3 Parts Per Thousand (ppt), which is similar to the salinity levels found in many other large lakes in the world. Additionally, Lake Superior receives a large amount of water from the many lakes and streams that feed into it, some of which have naturally occurring salt water.
Despite this, Lake Superior is still considered to be a freshwater lake, as the amount of saltwater that mixes with the freshwater is negligible. For example, the average salinity level of 0.3 ppt pales in comparison to the typical salinity levels of tropical oceans, which are typically between 30-38 ppt. This low salinity level is further due to the fact that Lake Superior is far enough away from the Atlantic Ocean, which is the main source of saltwater.
The fact that Lake Superior is a freshwater lake is to the benefit of the surrounding terrestrial aquatic food webs. The lack of saltwater means that a wide variety of fish and other aquatic species can inhabit the lake and its tributaries. This also helps to maintain the health of local watersheds, as many freshwater species require low salinity levels in order to survive, while saltwater species are unable to survive in such low salinity levels.
Lake Superior has been a source of fascination and admiration for centuries. A popular tourist attraction, the lake continues to draw in visitors from all over the world, with its crystal clear waters, vast expanses and diverse ecosystems. Although it is a freshwater lake, the lake still contains a healthy amount of salt, with its low salinity levels ensuring that it is ideal habitat for many species of freshwater fish. In doing so, Lake Superior ensures the survival and prosperity of its many inhabitants, just as it has done for generations.
Factors That Preclude Saltwater from Entering Lake Superior
Lake Superior is protected from the influx of saltwater by several different factors. The lake’s location makes it further from any potential sources of saltwater, such as the Atlantic Ocean. Additionally, the two rivers that connect Lake Superior to the ocean, the St. Mary’s and the St. Lawrence, are too short for saltwater to make a meaningful impact on the lake.
Furthermore, Lake Superior’s vast area ensures that the amount of incoming freshwater outweighs the amount of saltwater that enters it. The large watersheds the lake receives its water from also contain large amounts of freshwater, thus minimizing the effect of any small influx of saltwater. This also serves to reduce the amount of sediment in the lake, encouraging clearer and cleaner water.
Overall, the absence of significant saltwater influx is beneficial for Lake Superior. As the lake is a freshwater lake, the lack of saltwater means that the lake is able to sustain a greater variety of aquatic life, making it an ideal environment for fish, insects, and smaller aquatic organisms to live in.
The impact of the lack of saltwater can also be seen on the lake’s chemistry, with its low salinity levels allowing a greater range of organisms to live in the lake, such as certain species of freshwater fish. The effect of this is that the lake’s populations of fish, invertebrates and other aquatic species remain healthy and plentiful.
Why is it Important to Control the Salinity of Lake Superior?
The importance of controlling the salinity of Lake Superior can be seen in the lake’s vital role in the local freshwater ecosystem. The lake provides habitat, food, and water to a variety of species, ranging from plankton to fish such as lake trout, walleye and bass. The presence of freshwater species in the lake is partly due to the fact that the lake is less saline than other bodies of water, thus allowing species that require lower salinity levels to thrive.
The impact of maintaining a suitable salinity level in the lake can also be seen when it comes to water pollution. Pollutants often come in the form of chemical or heavy metals and can have a devastating impact on aquatic species. These pollutants become increasingly concentrated in waters of higher salinity, and a higher salinity level would make it increasingly difficult for Lake Superior to sustain its ecosystem and its native species.
The control of the salinity of Lake Superior is further important for economic and recreational reasons. People visit the lake and watersheds to take part in activities such as fishing and watersports, thus contributing to the local economy in the process. The lake’s low salinity level of 0.3 ppt provides the ideal environment for these activities, as it ensures that a variety of species can live in a healthy and prosperous environment.
Ultimately, the low salinity level and protection from saltwater sources that Lake Superior boasts are essential for the longterm health of the lake and its citizens. The salinity level of the lake must be maintained in order for it to continue to sustain a healthy and diverse ecosystem and for people to continue to visit and enjoy, for generations to come.
Effects of Low Salinity Level
The low salinity level in Lake Superior has several positive effects on its surrounding ecology, economy and recreation. On an ecological level, the low salinity ensures that a wide variety of species can inhabit the lake and its tributaries. This aids in maintaining the robustness and health of the local food web and also helps to preserve the lake’s biodiversity.
The low salinity level of Lake Superior also has benefits on the economic front. The presence of a wide variety of species establishes the lake as an ideal place for recreational activities such as fishing, thus encouraging people to visit and take part in such activities. This helps to generate revenue for the local economy and promote economic growth in the area.
Finally, the low salinity level ensures that people can continue to take part in activities such as swimming and watersports in the lake. The lack of saltwater means that the lake is far less harsh on the eyes, nose and skin when compared to other bodies of water. As such, people are able to enjoy the lake and its surrounding environment without having to worry about uncomfortable levels of salinity.
Uses of Salinity Levels
In addition to recreational and economic benefits, the salinity levels of Lake Superior also serve other important purposes. For example, it is used by scientists and researchers as a tool to gauge the health of the lake. High salinity levels often point to human activities such as industrial pollution and runoff, while low salinity levels point to a healthy and balanced ecosystem that is less prone to pollution and human interference.
The salinity level of the lake is also used to forecast weather patterns in the region, with rising levels often implying increased rainfall while declining salinity levels often pointing to periods of dry weather. This has been observed in the lake over the years, with changing salinity levels often correlating with changing weather patterns.
In addition, the salinity levels of the lake can also be used to gauge the level of nutrients in the water. With higher salinity levels usually meaning increased levels of nutrients, such as nitrogen, phosphorus and other chemicals, scientists are able to gain an insight into the health of the aquatic species in the lake.
Finally, the salinity level of the lake also has an effect on the taste of the water. While freshwater typically has a sweet taste, saltwater often has a more salty and bitter taste. As Lake Superior is largely freshwater, it has a mild and soothing taste that encourages people to take part in recreational activities in the lake.
Conclusion
The conclusion is that Lake Superior is unquestionably a freshwater lake. Not only is the lake far enough away from any source of saltwater, its vast area, extensive watersheds and rivers also ensure that the amount of freshwater outweighs any small influx of saltwater that might enter it. This has enabled the lake to maintain its characteristically low salinity level, with the resulting benefits being a healthy population of freshwater species, the ability to sustain recreational activities, the ability to forecast weather patterns and the health of the local ecosystem.
