What is the major nutrient of concern in lake deterioration?

Phosphorus is recognized as the major nutrient of concern in lake deterioration due to its critical role in the process of eutrophication. Eutrophication occurs when excess nutrients, particularly phosphorus, promote the overgrowth of algae and aquatic plants. This can lead to significant ecological imbalances, resulting in oxygen depletion, fish kills, and the degradation of water quality.

In freshwater ecosystems, phosphorus is often the limiting nutrient, meaning its availability largely dictates the rate of primary production by algae and aquatic plants. When phosphorus enters lakes from agricultural runoff, wastewater discharges, or other sources, it can trigger harmful algal blooms, which not only harm aquatic life but also impair water usage for recreation and drinking purposes.

While nitrogen is also important for aquatic ecosystems, it's phosphorus that is typically the primary driver of the problems associated with lake deterioration, making it the nutrient of greatest concern in this context. Potassium and calcium, while essential for various biological processes, do not have the same direct impact on lake water quality and the immediate issues of eutrophication as phosphorus does.