Eutrophication is the enrichment of nutrients in aquatic ecosystems. It starts when water receives an additional element, for example from agricultural activity, that fosters an excessive proliferation of organic matter. This causes an accelerated increase in algae and other green plants that cover the water’s surface, preventing sunlight from reaching the layers below. The water darkens, and as the amount of light decreases, the vegetation dies as it is unable to photosynthesise, increasing the activity of microorganisms that feed on dead organic matter. As a result of this, the levels of dissolved oxygen rapidly diminish, making it impossible for aquatic organisms to survive, as they need this oxygen for their biological processes.
The accumulation of nitrates in surface waters is mainly attributed to inappropriate agricultural practices that make incorrect and excessive use of nitrogen fertilisers, causing the dissolved nutrients they carry to be enriched, leading to eutrophication problems in the waters that take them in, thus diminishing their quality. This is the framework in which the EUTROMED project lies.