Coastal Zones

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Coastal Zones
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Essential Questions

• What are Coastal zones?
• What are the types of coastal zones?
• What are the characteristics of local coastal
  zones?

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Waves, Beaches and Coasts

• Answer the question sheet provided and place into
  your portfolio.
• http//www.learner.org/vod/vod_window.html?pid335
  
• 30 mins

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What are Coastal zones?
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The Coastal Zone
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What is a Coastal Zone?

• Also called a littoral zone
• Is part of a sea, lake, or river that is close to
  the shore
• Extends from the high water mark to shoreline
  areas that are permanently submerged

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Types of tides

• Neap Tide
• a less than average tide occurring at the first
  and third quarters of the moon
• Spring Tide
• tides with the greatest range between highs and
  lows, usually occurring during the full or new
  moons

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(No Transcript)
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What are the types of coastal zones?
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Types of Coastal Zones

• Supratidal aka supralittoral zone
• Intertidal aka eulittoral zone
• Subtidal aka sublittoral zone
• Continental shelf
• Continental margin

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Supratidal zone

• also called the splash, spray, or supralittoral
  zone
• the area above the spring high tide line that is
  regularly splashed, but not submerged by ocean
  water

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Organisms of the Supratidal zone

• patches of dark lichens can appear as crusts on
  rocks in the upper supratidal zone
• some types of periwinkles, Neritidae and detritus
  feeding Isopoda commonly inhabit the lower
  supratidal

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Intertidal zone

• also called the midlittoral or eulittoral zone
• is the area that is exposed to the air at low
  tide and underwater at high tide
• can be clearly separated into the following
  subzones
• high tide zone, middle tide zone, and low tide
  zone
• can include many different types of habitats
• steep rocky cliffs, sandy beaches, or wetlands
• water is available regularly with the tides but
  varies from fresh with rain, to highly saline,
  and dry salt with drying between tidal inundations

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Types of Intertidal zones

• Rocky intertidal communities
• occur on rocky shores, such as headlands, cobble
  beaches, or human-made jetties
• tend to have higher wave action
• Soft-sediment habitats include
• sandy beaches, and intertidal wetlands (e.g.,
  mudflats, and salt marshes)
• are generally protected from large waves but tend
  to have more variable salinity levels

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Organisms of the Intertidal zone

• plankton
• filter feedersmussels, clams, barnacles, sea
  squirts, and polychaete worms
• Sea stars
• scavengers crabs and sand fleas

• autotrophs ranging from microscopic algae, to
  huge kelps and other seaweeds
• limpets and kelp crabs
• Goliath Grouper
• sharks

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Subtidal zone

• also called the Coastal Ocean, Neritic or
  sublittoral zone
• extending from the low tide mark to the edge of
  the continental shelf
• has generally well-oxygenated water, low water
  pressure, and relatively stable temperature and
  salinity levels
• areas where sunlight reaches the ocean floor,
  that is, where the water is never so deep as to
  take it out of the photic zone

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Types of Subtidal zones

• The sublittoral zone is further divided into 2
  regions
• The infralittoral zone
• extends to five metres below the low water mark
• the algal dominated zone
• The circalittoral zone
• the region beyond the infralittoral
• dominated by sessile animals such as oysters.

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Organisms of the Subtidal zone

• Corals are more common in the subtidal zone
• Zooplankton live in this zone and together with
  the phytoplankton form the base of the food
  pyramid that supports most of the world's great
  fishing areas

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Continental shelf

• is the extended perimeter of each continent and
  associated coastal plain
• the stretch of the seabed adjacent to the shores
  of a particular country to which it belongs
• known as Territorial waters
• abruptly terminates with the continental slope

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Continental Margin

• between the continental shelf and the abyssal
  plain
• comprises a steep continental slope followed by
  the flatter continental rise
• margins constitute about 28 of the oceanic area

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Continental Slope and Rise

• Continental rise
• found between the continental slope and the
  abyssal plain
• an underwater hill composed of tons of
  accumulated sediments

• Continental slope
• usually begins at 430 feet depth and can be up to
  20 km wide
• connects the continental shelf and the oceanic
  crust
• the average angle is 3, but it can be as low as
  1 or as high as 10

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Over the EdgeThe Endless Voyage Series

• http//learning.aliant.net/Player/ALC_Player.asp?P
  rogIDINT_ENDVOY11
• Complete the Self Test after watching the video
• 27mins

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What are the characteristics of local coastal
zones?
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The Continental Shelf of NS

• The continental shelf extends from 125-230 km
  offshore to depths of about 200 metres.
• Major offshore areas that make up the shelf are
  the Northumberland Strait, southeastern Gulf of
  St. Lawrence, Sydney Bight, Scotian Shelf,
  Georges Bank, Gulf of Maine, and Bay of Fundy.
• Features include basins up to 280 m deep on the
  central shelf fishing banks channels and Sable
  Island, on Sable Island Bank, extending 26 m
  above sea level.

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The divisions in NS

• Four major geological or bedrock units are
  represented
• (1) the Acadian Basin, an area of Triassic rocks
  in the Bay of Fundy and northern Gulf of Maine,
• (2) terrestrial bedrock extending to 25 km
  off-shore along the Atlantic coast of Nova Scotia
  and into basins on the south side of the Gulf of
  Maine,
• (3) an outer area comprising the Middle and Outer
  Scotian Shelf, consisting of Jurrasic,
  Cretaceous, and Tertiary rocks and including
  Georges Bank, the outer Gulf of Maine, and the
  outer part of the Laurentian Channel,
• (4) Sydney Basin, an area of carboniferous rocks
  northeast of Cape Breton Island

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Plant Life

• Beds of kelp and other marine algae grow on the
  seabed close to shore
• microscopic phytoplankton occur both nearshore
  and in most other waters
• There are 2 types of attached plants
• those attached to rocks
• kelps and rockweeds but more than 300 species of
  seaweed occur around Nova Scotia coasts
• those in soft bottom
• Eelgrass

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Animals

• grazing vertebrates, invertebrates and suspension
  feeders such as mussels, scallops and oysters
• grazers such as sea urchins
• groundfish cod, haddock, pollock, halibut, and
  various species of flatfish
• herring, mackerel, Bluefin Tuna, capelin, and
  some smaller species
• Seabirds Herring and Black Back gulls, Great
  and Double-crested cormorants
• oceangoing birds shearwaters, terns, jaegers,
  phalaropes, and Storm-petrels
• Nesting colonies of gannets, puffins, petrels,
  and kittiwakes

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Other Features of Coastal Zones

• Sand dunes
• Estuaries
• Littoral drift
• the process by which sediment is continuously
  moved along beaches by wave action
• occurs because waves hit the shore at an angle,
  pick up sediment (sand) on the shore and carry it
  down the beach at an angle
• helps create many landforms including barriers,
  bay beaches and spits