Nutrient Dynamics in Freshwater Ecosystems and Solutions to Eutrophication

Eutrophication is one of the growing threats to freshwater habitats, which involves nutrient loading and subsequent destabilization of the ecosystem functioning due to excess nutrients such as (N) and (P). This article explores the issue of nutrient dynamics in freshwater communities paying special attention to nutrient loading processes, internal cycling, and its impacts on ecological processes within a chosen lentic ecosystem study site. The analysis combines empirical data collected during a field study with spatial modeling of nutrient flows to determine seasonal and spatial variability of N and P concentrations, measures of trophicity, and algal bloom dynamics. As shown, both total phosphorus (TP) and total nitrogen (TN) exceed recommended concentrations (TP > 50 μg/L; TN > 1.5 mg/L) leading to the onset of hyper eutrophication and cyanobacterial blooms. An important role in phosphorous cycling is played by the internal loading due to phosphorous sediments released under anoxic conditions. Several strategies for managing nutrient loads are considered, and the integrated approach combining physical, chemical, and biological measures appears to be most effective, achieving a 47–62% decrease in phosphorous loading through the use of alum and construction of wetlands.