Salt marshes are coastal wetlands that are flooded and drained by salt water brought in by the tides. They are marshy because the soil may be composed of deep mud and peat. Peat is made of decomposing plant matter that is often several feet thick. Peat is waterlogged, root-filled, and very spongy. Because salt marshes are frequently submerged by the tides and contain a lot of decomposing plant material, oxygen levels in the peat can be extremely low--a condition called hypoxia. Hypoxia is caused by the growth of bacteria which produce the sulfurous rotten-egg smell that is often associated with marshes and mud flats. Continue reading in National Ocean Service
Salt Marsh is a wetland that has shallow water and levels that usually fluctuate due primarily to tides along the coast or changes in water depth in depressions. Coastal salt marches are primarily intertidal; that is, they are found in areas at least occasionally inundated by high tide but not flooded during low tide, including estuaries, lagoons, and the lee side of barrier islands. The vegetation comprises emergent shrubs and herbs with at least 10%cover, especially saline or halophytic species.They occur at all latitudes around the globe, but are concentrated in the temperate mid-latitudes(23-70°N and S). Continue reading from NatureServe Explorer
Although not always pleasing to our human sense of smell, salt marshes are the "ecological guardians of the coast" that maintain healthy fisheries, coastlines and communities. They provide shelter, food and nursery grounds for more than 75% of coastal fisheries species including shrimp, crab and many fish. Salt marches also protect shorelines from erosion by creating a buffer against wave action and by trapping soils. In flood prone areas, salt marshes reduce the flow of flood waters and absorb rainwater. By filtering runoff and excess nutrients, salt marshes also help to maintain water quality in coastal bays, sounds and estuaries. Salt marshes and other coastal wetlands also serve as "carbon sinks," holding carbon that would otherwise be released into the atmosphere and contribute to climate change.
The U.S. has experienced tremendous losses of freshwater and coastal wetlands since the early 20th century, primarily from construction, development and habitat loss. The U.S. Fish and Wildlife Service estimated that between 2004 and 2009 alone, wetlands in coastal watersheds declined by 360,720 acres or over 80,000 acres per year. The National Park Service puts a high priority on wetland protection and restoration. Continue reading from National Park Service
11 Facts about Salt Marshes and Why We Need to Protect Them (Pew)
Understanding the Importance of Salt Marshes (Eos)
Salt Marshes in Connecticut Aim to Create More Resilient Coastline (Audubon)
Our Historic Salt Marshes (Connecticut Explored)
NASA Scientists Map Global Salt Marsh Losses and Their Global Impact (NASA)
