Rehevöityvä

Rehevöityvä is a Finnish term that describes the process of eutrophication, specifically in aquatic ecosystems. It refers to the enrichment of water bodies by nutrients, primarily nitrogen and phosphorus. This influx of nutrients can originate from various sources, including agricultural runoff, sewage discharge, industrial waste, and atmospheric deposition.

When excessive nutrients enter a lake, river, or coastal area, they fuel rapid growth of algae and aquatic plants. This phenomenon is often referred to as an algal bloom. The dense growth of these organisms can deplete dissolved oxygen in the water, especially when they die and decompose. This oxygen depletion, known as hypoxia or anoxia, can have severe consequences for aquatic life, leading to fish kills and a decline in biodiversity.

The visual characteristics of a rehevöityvä water body often include murky water, a green or brown discoloration due to algae, and potentially foul odors from decaying organic matter. In some cases, the excessive plant growth can form thick mats on the water surface, hindering light penetration and further impacting submerged vegetation. The overall ecological balance of the water body is disrupted, shifting towards a less diverse and often less desirable state for human use and enjoyment. Addressing rehevöityvä typically involves reducing nutrient inputs from their sources.