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Marshes

At a Glance: Tidal vs Non-Tidal Marshes

What are the differences between tidal and non-tidal marshes?
Credits

Produced by the Space Telescope Science Institute’s Office of Public Outreach in collaboration with the NASA Earth Observatory.

All images, illustrations, and videos courtesy of NASA except:
·       Celtic Monster illustration by John Dickson Batten
·       Phosphate mine photo courtesy of Pamlico-Tar River Foundation, Washington, North Carolina
·       Horicon Marsh photos and marsh wildlife photos courtesy of Andrea Gianopoulos
·       Sea creature illustration copyright The National Library of Israel, Shapell Family Digitization Project _and The Hebrew University of Jerusalem, Department of Geography – Historic Cities Research Project
·       Assateague Island marsh photos courtesy of Lucy Albert
·       Muskrat photo courtesy of Dan Leveille
·       Peat fire photo courtesy of Guillermo Rein
·       Marsh algae photos courtesy of Andrea Gianopoulos
·       Close-up Lake Carnegie satellite image courtesy of the USGS EROS Data Center Satellite Systems Branch
·       Photos of Tigris River and drained Mesopotamian Marshes courtesy of Dr. Michelle Stevens, iraqmarshrestoration.blogspot.com
·       Photo of boatmen in an Iraqi marsh courtesy of Hassan Janali, U.S. Army Corps of Engineers
 
Music courtesy of Associated Production Music
Written by Andrea Gianopoulos
Designed by Marc Lussier
Transcript

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An animation of Earth in a star-filled sky. Text, at-a-GLANCE, Marshes
 
There are two types of marshes.
 
Italy and Florida.
 
Italy, Tidal. Florida, Non-Tidal
 
Tidal marshes are found along protected coastlines. They can be freshwater, salt water, or brackish (slightly salty) marshes, but all are influenced by the motion of ocean tides. Tidal marshes are important coastline buffers. They slow shoreline erosion and protect the coast from stormy seas. They also protect oceans by absorbing sediment and excess nutrients that rivers carry to the sea.
 
A red circle highlights a Tidal Marsh, Venetian Lagoon, Italy.
 
The Venetian Lagoon holds salt marshes and is the largest wetland in the Mediterranean basin.
 
Non-tidal marshes are the most common wetlands in North America. They hold mostly fresh water, but some are brackish.
 
A red circle near Lake Okeechobee highlights a Non-Tidal Marsh, Florida Peninsula. The Everglades in southern Florida are a vast array of wetlands, including many non-tidal marshes.
 
Water leaving Lake Okeechobee forms a vast, 60-mile-wide, slow-moving river that flows southward to Florida Bay.
 
Suspended sediment is carried to Florida's southern shoreline, making it appear turquoise in this image.