Salt marshes appear as vast dynamic and constantly changing wet lands with fields of grasses; complex ecosystems with various plants like rushes, sedges, and grasses – as well as animals and microbes in various stages of life that all coexist in a fragile balance with their environment and with each other. Salt marshes are important to the estuaries and other coastal waters that surround them as the tides bring sea water into and out of the marsh twice a day. The organisms that live in salt marshes must be able to live in salty water and salty soils. At high tide, the marsh can be completely covered with water. At low tide, it can be completely dry and exposed to the sun. Salt marsh organisms have to be able to live in both wet and dry conditions.
Salt marshes are found on shorelines that are sheltered from ocean waves. Some salt marshes are narrow, fringing marshes and other cover vast acres. They are found on steep coasts, between the water and dry land and salt marshes several miles wide are primarily found near the mouths of rivers, in bays, and in protected lagoons. In some warmer climates, mangrove trees take the place of marshes – which are adapted to both a warmer climate and salt water.
In the Americas these transitional areas are found along coastlines in Florida, South Carolina, Mexico, and in Central and South America – and are considered an important a source of nourishment for many species and a unique and important ecosystem that we must preserve as one of our great natural heritages.