salt marshes Flashcards
what are salt marshes
-transitional intertidal area between land and salty/brackish water
where do salt marshes develop
-in sheltered areas where deposition occurs
-where salt and fresh water meet
-where there are no strong tides or currents to prevent sediment deposition and accumulation
what is the effect of tides on salt marshes
-covered at high tide
-exposed at low tide
formation of salt marsh
-as mud flats develop, salt tolerant plants colonise and stabilise them
-halophytes (salt tolerant) such as glasswort help slow down tidal flow and trap more mud and silt
-sediment accumulates so surface becomes drier and different plants colonise
-creeks divide up salt marsh
what is a creek
small flow of river
what occurs at the tidal creek
-partial or constant submersion
-salt tolerant species are only ones to develop
what happens just after the tidal creek
-submersion from high tide only partial so diverse species develop
what happens in the high marsh
more species provide more roots to stabelise soil raising it above the level of tidal range
what happens in the marsh border
-diverse community of salt intolerant species can develop
plants that form at the algal stage of a salt marsh
-blue green algae which can grow on and within mud binding it together
plants that grow on pioneer stage of salt marsh
-glasswort
-roots stabelise but
plants that grow during establishment stage
-salt marsh grass
-carpet of vegetation established and salt marsh height increases
climax vegitation
-sedge
-developed soil profile only submerged once or twice a year
what coasts are salt marshes developed on
-depoisitional coasts
-where tidal action is gentle and erosion is intermittent and light enough to allow vegetation to take hold
