ABSTRACT
Salt and brackish marshes are highly productive habitats that occur at the intersection between the ocean and the land. They are the result of the interactions among vegetation, sediments, and the tides. Marsh plants capture sediments carried by rivers, thereby elevating the habitat above sea level. Salt and brackish marshes are exposed to contrasting salinities because they occupy different locations along an estuarine gradient. Coastal marshes provide many important services to humans including coastal protection, erosion control, and the maintenance of fisheries. However, humans have dramatically changed marshes for agriculture, development, and resource extraction; it is estimated that 50% of the coastal marshes in the United States are gone. In addition to direct human impact, marshes are highly susceptible to climate change via sea-level rise, terrestrial flooding, and extreme disasters in the form of hurricanes and tsunamis. The future of salt and brackish marshes will depend on conservation, restoration, and climate.
