Mudflats And Saltmarshes Flashcards
Why are river estuaries important
They are large sediment stores where huge quantities of river sediment are deposited
What sediment accumulates at river estuaries
Most sediment that accumulates here is mud due to low velocities. This causes mudflats to form and develop into saltmarshes
What is a saltmarsh
An area of flat silty sediments that develop around estuaries or lagoons
What environments do saltmarshes occur in
Sheltered areas where deposition occurs
Where salt and freshwater meet
What are halophytes
A salt tolerant species that colonise and stabilise the saltmarshes
What happens during high and low tide
Saltmarshes are covered during high tide and exposed at low tide
What is the process of sand dune development
Mud is deposited close to the high tide line dropping out of the water by flocculation
Pioneer plants colonise transition zones between high and low tides these are called halophytes
Gradually the mud level rises above the high tide line
Next it develops with a wider range of plants that no longer need to survive salty water
Soil conditions improve and the vegetation succession continues to form a meadow
Eventually shrubs and trees will colonise
What is flocculation
When tiny individual particles of clay stick together, their combined mass enables them to sink to the sea bed
Why won’t a sand dune reach climatic climax
Because it will always be interrupted by the sea unless something like climate change interrupts
