Ästuare, or estuaries, are coastal areas where freshwater from rivers meets and mixes with saltwater from the ocean. These unique environments are characterized by their brackish water, which supports a diverse range of plant and animal life. Estuaries serve as crucial habitats for many species, including fish, birds, and invertebrates, making them vital for biodiversity. Estuaries also play an important role in the ecosystem by acting as natural filters, trapping pollutants and sediments before they enter the open ocean. Additionally, they provide essential services such as flood protection and nursery grounds for commercially important species like fish and crustaceans.