Question | Answer |
estuary | the areas of water and shoreline where a freshwater stream or river merges with the ocean |
Salt-Wedge Estuaries | when the mouth of a river flows directly into salt water (Mississippi, Columbia and Hudson rivers) |
Fjord | characterized by a deep elongated basin that is U-shaped and a ledge or barrier that separates the basin from the sea. Found along glaciated coasts--Alaska, Norway |
Slightly Stratified or Partially Mixed Estuary | have a tidal flow that provides a means of erasing the salt wedge--Puget Sound, San Francisco Bay |
Vertically Stratified or Well Mixed Estuaries | have strong tidal mixing and low river flow that mix the sea water throughout the shallow estuary--Delaware Bay |
Freshwater Estuaries | occur where massive freshwater systems, as the Great Lakes, are diluted by river or stream waters draining from adjacent lands |
Common Estuarine Habitats | oyster reefs
kelp forests
rocky and soft shorelines
submerged aquatic vegetation
coastal marshes
mangroves forests
mud flats
tidal streams
barrier beaches
salt marshes
deepwater swamps and riverine forests |
Salt pannes and pools | water retaining depressions located within salt and brackish marshes |
Invasive species | species that do not naturally live in an estuary, but were introduced, often accidentally, by humans |
Kelp Forests | occur in cold, nutrient-rich water of shallow open coastal waters |
Rocky Shorelines and Bottoms | have hard surfaces made of stones, boulders and bedrock |
Soft Shores and Bottoms | low-lying sand beaches, muddy shores and mudflats made of sediments that have mixed with detritus (think of muck or ooze) |
Submerged Aquatic Vegetation | also called SAV, are beds of leafy rooted, grass-like plants with tiny flowers, found in shallow waters where light can penetrate |
Coastal Marshes | composed of upright plants that live above the water surface, often with their roots submerged |
Mangroves | trees that can survive in very salty areas |
Deepwater Swamps and Riverine Forests | flooded, forested wetlands growing near edges of lakes, rivers and sluggish streams |
Mud Flats and Sand Flats | part of benthic (bottom) zone exposed at low tide and comprised of extremely fine sediments |
Tidal Streams | highly productive transitional areas between the freshwater of rivers and the salt water of bays |
Barrier Beaches | spits of sand that form parallel to the shore |
Salt Marshes | wetland flooded regularly by tidal, brackish water |