Salt marshes are areas of periodically flooded low-lying coastal wetlands.
They are often rich in plants, birds and animals.
Vegetation Succession
A salt marsh begins life as an accumulation of mud and silt in a sheltered part of the coastline, e.g. in the lee of a spit or a bar.
As more deposition takes place, the mud begins to break the surface to form mudflats.
Salt-tolerant plants such as cordgrass soon start to colonise the mudflats - early colonisers are known as pioneer plants.
Cordgrass is tolerant of saltwater and its long roots prevent it from being swept away by waves and tides, as well as helping to trap sediment and stabilise the mud.
As the level of mud rises, it is less frequently covered by water.
The conditions become less harsh as rainwater begins to wash out some of the salt, and decomposing plant matter improves the fertility of the newly forming soil.
New plants such as sea asters start to colonise the area and gradually, over hundreds of years a succession of plants develops. (vegetation succession)
Pioneer Plant: The first plant species to colonise an area that is well adapted to living in the harsh environment. Vegetation Succession: A sequence of vegetation species colonising an environment.