Here's a breakdown of the key features:
* Shallow: Lagoons are typically not very deep, often less than 10 meters.
* Separated: They are distinct from a larger body of water like an ocean, sea, or lake.
* Barrier: The barrier separating the lagoon can be natural, such as a coral reef or sandbar, or artificial, like a dam or levee.
Types of lagoons:
* Coastal lagoons: These are the most common type, formed along coastlines.
* Atoll lagoons: Located within the ring of islands that make up an atoll.
* Lake lagoons: Formed within a lake by a barrier of land or vegetation.
Characteristics:
* Often salty: Lagoons are usually influenced by saltwater from the ocean, but their salinity can vary depending on the amount of freshwater input.
* Rich in biodiversity: Lagoons can support a wide variety of life, from fish and birds to plants and algae.
* Vulnerable to pollution: Their shallowness and connection to the ocean can make them susceptible to pollution from human activities.
Examples:
* The Great Barrier Reef Lagoon (Australia): The largest lagoon in the world, home to a vast coral reef system.
* Venice Lagoon (Italy): A complex system of canals, islands, and waterways in the Adriatic Sea.
* Lake Pontchartrain (Louisiana, USA): A large lake lagoon connected to the Gulf of Mexico.