![]() Gradually, the sediments built up to the degree that they were no longer underwater at low tide. Ocean currents and tidal rivers flowing into the quiet lagoons deposited large amounts of clay and sand sediments there. Rising sea levels from melting continental glaciers created shallow lagoons behind young barrier islands. The origin of the salt marshes can be traced to a period near the end of the Pleistocene geologic epoch, about 18,000 years ago. Tidal Creek, Sapelo Island Courtesy of Georgia Department of Economic Development. The potential damage from large storm-spawned waves and tides is greatly reduced when they pass over the marshes. In addition, salt marshes help filter pollutants from the water and act as buffers against offshore storms. Young shrimp and other marine organisms also use salt marshes as shelters and hiding places from predators. The enormous productivity helps to make the salt marshes primary nursery areas for blue crabs, oysters, shrimp, and other economically important fish and shellfish. According to the Georgia Department of Natural Resources, they produce nearly twenty tons of biomass to the acre, which makes them four times more productive than the most carefully cultivated cornfields. ![]() Georgia’s salt marshes are some of the most biologically productive natural systems on Earth. ![]() The Georgia Department of Natural Resources estimates that the state encompasses more than 378,000 acres of salt marsh. The study, however, did not distinguish between salt marsh and freshwater marsh. In 1977 the National Aeronautics and Space Administration reported that Georgia had 429,294 acres of tidal marshland, more than any other state on the East Coast. Estimates of Georgia’s total tidal marshland acreage vary.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |