Abstract

The pollution of nitrogen (N) and phosphorus (P) is also an acute environmental problem at the global level, which contributes to the intensive process of eutrophication of freshwater, estuarine, and coastal aquatic environments. The overloading of nutrients, which is mainly caused by nonpoint sources such as agricultural runoff, wastewater discharge, and atmospheric deposition, initiates harmful algal growth, lowers the transparency of the water, and decays the dissolved oxygen (hypoxia) and biodiversity. To solve this ubiquitous issue, it is necessary to change the traditional single nutrient management approach to source-to-sink control. This study introduces a combined model where it is essential to consider innovative methodologies of nutrient reduction, such as improving watershed management methodologies and new ecotechnologies. The framework focuses on an amalgamation of Best Management Practices (BMPs), including high-level fertilizer optimization, and state-of-the-art ecological design, including constructed wetlands blended with specific adsorption media. The Soil and Water Assessment Tool (SWAT) algorithm is included in the prediction model based on the transport of nutrients, and it allows for the best location of mitigation actions. The general Discussion of the different ways of addressing the problem reveals the need to implement site-specific solutions. The most important one is that a holistic management model that aims at achieving N and P reduction and the recovery of resources is proposed. This will help reestablish the ecological balance, improve the quality of water, and assist in maintaining the health of the aquatic ecosystems.

Keywords: Nutrient pollution, Eutrophication, Nitrogen, Phosphorus, Mitigation, Aquatic ecosystems, Integrated management