Laguunijärvi

A laguunijärvi, also known as a lagoon lake or coastal lagoon, is a shallow body of water that is separated from a larger body of water, typically the sea, by a natural barrier. This barrier is often a sandbar, a coral reef, or a spit. The water in a laguunijärvi can be brackish, meaning it is a mixture of freshwater and saltwater, or it can be almost entirely freshwater or saltwater depending on the degree of connection to the open sea and the amount of freshwater input from rivers or rainfall.

These geological formations are found in various coastal environments around the world. They are characterized by their relatively calm waters due to the protection offered by the barrier. The salinity levels can fluctuate significantly due to tidal influences, rainfall, and evaporation. Laguunijärvet often support unique ecosystems, providing habitats for a diverse range of flora and fauna adapted to these specific conditions. They can be important nursery grounds for fish and invertebrates, and they often attract migratory birds.

The formation of a laguunijärvi is a dynamic process influenced by coastal erosion, sediment deposition, and sea-level changes. Over time, the physical characteristics of a laguunijärvi can change, with some gradually filling in with sediment and becoming marshland or even disappearing entirely. Others may be subject to breaches in their protective barriers, allowing for greater exchange with the adjacent sea.