The role of salt marshes in the coastal system - Essay Example

Since salt marshes are shallow areas, the plants that exist in salt marshes are those that can adapt to the tidal changes in the volume of water. The water waves that make it to the salt marshes carry with them tons of organic material which accumulate overtime to form peat. There are many varieties of salt marshes namely: low marsh, high marsh, panes and pools and upland border. Apart from providing thick vegetation, salt marshes are also amongst the most productive ecosystems in the world (New Hampshire Department of Environmental Services, 2004).

Role of Salt Marshes in the Coastal System: Salt marshes are sometimes referred to as tidal marshes, the reason being that salt marshes are found in zones between high and low tide. Salt marshes thrive well along the coastal areas because the vegetation is not sturdy enough to withstand strong waves, therefore towards the coastal areas, where the intensity of the waves is reduced to quite an extent, salt marshes thrive (Casagrande, 1997). Salt marshes serve many purposes, namely; they cleanse pollutants from marine water, provide a habitat to many marine species, provide a barrier against soil erosion, provide a source of refuge for the vulnerable marine species, salt marshes are rich in organic matter therefore they form a food chain for the marine life and also provide good nutrient value for the vegetation in the salt marshes (Department of Environmental Protection: Florida Marine Reseach Institute, 2010).

Let us throw some light on the varied roles of salt marshes: Remove Pollutants from the Water Since the speed of the waves reduces considerably by the time they reach salt marshes, many suspended particles that are otherwise carried away by the waves throughout the sea, tend to settle. These suspended particles sometimes comprise of toxic nutrients from human activities, thus by allowing them to settle the salt marshes play a key role in cleansing the water of toxic sediments. The thick vegetation helps in slowing down the waves which in turn causes the particles to settle.

Furthermore, during the months of summer and spring the salt marshes’ plants take up the nutrients which if left in the water, would turn into algae, further polluting the water by causing “Eutrophication” and thus depleting the oxygen supply of the water (Cloern, 2007). The toxic contaminants which are settled by the salt marshes form peat which results in the removal of these toxic substances from the marine food web. Moreover, the microbes present in the salt marshes tend to remove nitrogen from the ecosystem (Edwards, 2010).

This is beneficial even to the surrounding eelgrass. The reason behind this is that the existence of high levels of nitrogen encourages the growth of phytoplankton. Phytoplankton refers to microscopic organisms that live in water (Lindsey, 2010). This phytoplankton, when in excess blocks the sunlight which is needed for eelgrass to thrive. Therefore, the presence of salt marshes also benefits eelgrass. Harbour Marine Food Chains The excessive nutrients found in the salt marshes form food chains for marine species.

Primarily, the plant matter that partially decays in the salt marshes forms a good source of food for marine species in the deeper waters. This decayed vegetation is taken away by the tidal waves into the ocean where it becomes the food of many marine animals. A two way process runs between aquatic