Marine Ecosystems Quiz

Study Notes

Marine ecosystems include oceans, salt marshes, intertidal habitats, estuaries, lagoons, mangroves, coral reefs, and the deep sea and sea floor.
They are contrasted with freshwater ecosystems, which have a smaller salt content.

Considered ecosystems because plant life supports animal life and vice-versa.
Provide fish habitat, food, shelter from predators and competitors, migration routes, and reproduction cues.
Critical habitats include salt marshes, intertidal ecosystems, lagoons, estuaries, mangroves, beaches, coral reefs, and seagrass beds.

Transitional area between land and salty or brackish water (e.g., sloughs, bays, estuaries).
Dominated by halophytic (salt-tolerant) herbaceous plants.
Considered one of the most biologically productive habitats on the planet, rivaling tropical rainforests.
Tidal surges bring in nutrients, which tend to settle in plant roots, and natural chemical activity of salty water and algae blooms allow for great biodiversity.

Study of intertidal ecosystems involves interactions between organisms and their environment, as well as between different species within a community.
Organisms live between low and high tide lines, with exposure at low tide and immersion at high tide.
Vertical zonation is a key characteristic of intertidal ecosystems.

Shallow, semi-enclosed, and sheltered littoral bodies of water.
Lagoons: semi-enclosed coastal basins with limited freshwater input, high salinity, and restricted circulation.
Estuaries: semi-enclosed coastal basins where freshwater from rivers mixes with saline water from the ocean.
Bays: more open littoral basins with flow not as restricted and salinity levels approaching the open sea.
Favorable conditions in these ecosystems include a wide range of salinity, near total light penetration, large quantities of organic nutrients, and high rates of vertical mixing.

Uses: harbors, disposal sites, recreation, science and education, aquaculture, transport, fishing, sand mining, seed fish and shrimp collection, ornamental fish collection, gleaning, and desalination.
Threats: pollution from domestic sewage waste, domestic solid waste, sediments from erosion and construction, mine tailings, industrial organic and toxic wastes, agricultural chemicals, oil and fuel leaks, and landfills.