rehevöittävää

Rehevöittävää is a Finnish term that translates to "eutrophication" in English. It describes the process by which a body of water becomes overly enriched with minerals and nutrients, primarily nitrogen and phosphorus. This enrichment often leads to excessive growth of algae and aquatic plants. When these organisms die and decompose, they consume large amounts of dissolved oxygen in the water, a process known as hypoxia or anoxia. This depletion of oxygen can create dead zones where fish and other aquatic life cannot survive.

The primary causes of eutrophication are human activities, particularly agricultural runoff containing fertilizers and animal waste, as well as wastewater discharge from sewage treatment plants. Industrial pollution can also contribute. Natural sources of nutrients, such as geological weathering and atmospheric deposition, exist but are typically less significant in causing severe eutrophication.

Symptoms of eutrophication include increased algal blooms, often visible as green or brown scums on the water surface. These blooms can block sunlight from reaching submerged aquatic vegetation, hindering its growth. Changes in water clarity, odor, and taste are also common. The ecological impacts are significant, leading to a loss of biodiversity and a decline in the overall health of aquatic ecosystems. Management strategies focus on reducing nutrient inputs from various sources, such as improving wastewater treatment, implementing better agricultural practices, and controlling urban runoff.