Week 1 - Introduction To Coastal Environments Flashcards
What is a coastal environment?
An interface between the land and sea where marine and terrestrial areas influence each other
What are some examples of coastal environments?
Beach
Fjord
Tidal wetland
Rocky cliff
Coral reef
Estuary
Mangrove
What is the coastal zone?
An area influenced by its proximity to the coast
What is the offshore zone
A portion of the profile where there is no significant transport of sediment by wave action
What is the littoral zone
The portion of the coastal profile where sediment can be transported by wave action
What is the shore/beach
A portion of the profile that is subject to wave action
It is exposed sub-aerially at least some of the time
What is the intertidal zone
The area where the ocean meets the land between high and low tides
What is the nearshore
The portion of the profile extending from low tidal limit, to start wave action
Describe the rocky coast
Characterised by erosion
High energy environment
Typically located in active margins
Composed of any rock type
Usually the site of complex tectonic landforms
Describe the sandy coast
Highly dynamic environment
Subject to rapid and extreme changes
High offshore sediment influence
Found in wave-dominated, depositional settings
Location and form are a function of sediment supply and coastal processes
Geological features include: barrier Islands, barrier sits, dunes, tombolos
Describe an estuary
Semi-enclosed, elongated coastal basin
Received an inflow of both freshwater and saltwater
Marine/terrestrial interface
Affected by tidal oscillations and river discharge
Vulnerable to compound flooding
Shape and size of estuary can dictate hydro- and sediment dynamics
Most estuaries are young basins (geologically speaking)
Established by the flooding of fluvial (river-eroded) or glacially scoured valleys during the Holocene rise of sea level
Describe deltas
Where rivers provide large quantities of sediment to the shore
Estuaries are filled and river sediments are discharged directly into the ocean
Build-up of sediment occurs at river mouths if the rate of sediment supply exceeds the rate of sediment removal by waves and tidal currents
Deposits, which commonly assume triangular shapes in planar view, are termed deltas because they resemble the Greek letter delta
describe coral reefs
Same physical processes than in other latitudes
In warm tropical waters, colonies of corals form, mostly between 30 degrees north and 30 degrees south latitude
Corals are stationary – their food source is washed to them through continuous water motions
Living corals require a minimum sea temperature for growth
They are concentrated in the tropics
Vulnerable to bleaching when water temperature increases
Favour clear waters – cannot live in deltas or muddy environments
Generally depths shallower than 75 ft, some species tolerate depths of up to 500 ft
Most well-known = barrier reef
Built in shallow waters
May reach enormous proportions e.g. Great Barrier Reef
why are coastal environments important to the economy
Storm protection
Jobs
Residence
Tourism
Shipping
Energy
Food
Fisheries
why are coastal environments important to the environment
Home of flora and fauna species
Primary protection
Habitats
Nutrient cycling
Regulating:
Link between ocean and land
Energy exchange
