Ch. 7 Aquatic Ecosystems Flashcards
Wetland
land consisting of marshes or swamps; saturated land.
Plankton
Plankton are the diverse collection of organisms found in water that are unable to propel themselves against a current. The individual organisms constituting plankton are called plankters. In the ocean, they provide a crucial source of food to many small and large aquatic organisms, such as bivalves, fish and whales.
Nekton
Nekton (or swimmers) are living organisms that are able to swim and move independently of currents. Nekton are heterotrophic and have a large size range, with familiar examples such as fish, squid, octopus, sharks, and marine mammals.
Benthos
Benthos (from Ancient Greek βένθος (bénthos) ‘the depths (of the sea)’), also known as benthon, is the community of organisms that live on, in, or near the bottom of a sea, river, lake, or stream, also known as the benthic zone.
Littoral zone
The littoral zone is the near shore area where sunlight penetrates all the way to the sediment and allows aquatic plants (macrophytes) to grow. Light levels of about 1% or less of surface values usually define this depth. … The bottom sediment, known as the benthic zone, has a surface layer abundant with organisms.
Benthic zone
The benthic zone is the lowest ecological zone in a water body, and usually involves the sediments at the seafloor. These sediments play an important role in providing nutrients for the organisms that live in the benthic zone.
Eutrophication
excessive richness of nutrients in a lake or other body of water, frequently due to runoff from the land, which causes a dense growth of plant life and death of animal life from lack of oxygen.
Estuary
the tidal mouth of a large river, where the tide meets the stream.
Salt marsh
A salt marsh or saltmarsh, also known as a coastal salt marsh or a tidal marsh, is a coastal ecosystem in the upper coastal intertidal zone between land and open saltwater or brackish water that is regularly flooded by the tides.
Mangrove swamp
Mangrove swamps are coastal wetlands found in tropical and subtropical regions. They are characterized by halophytic (salt loving) trees, shrubs and other plants growing in brackish to saline tidal waters. … Mangrove trees dominate this wetland ecosystem due to their ability to survive in both salt and fresh water.
Barrier island
Barrier islands are coastal landforms and a type of dune system that are exceptionally flat or lumpy areas of sand that form by wave and tidal action parallel to the mainland coast. They usually occur in chains, consisting of anything from a few islands to more than a dozen.
Coral reef
A coral reef is an underwater ecosystem characterized by reef-building corals. Reefs are formed of colonies of coral polyps held together by calcium carbonate. Most coral reefs are built from stony corals, whose polyps cluster in groups.
