marine biome and human impact -...
TRANSCRIPT
Marine Biome and
Human Impact
Topics: Marine Biome and Human Impact
1. Oceans
2. Coral Reefs
3. Shorelines a. Weathering
b. Erosion
c. Longshore movement
d. Erosional Features
e. Depositional Features
4. Threats to Marine Biome a. Oceans
b. Coral Reefs
c. Human Impact on Shorelines
Oceans http://mbgnet.mobot.org/salt/sandy/
1. Play an integral role in many of
the Earth's systems including
climate and weather.
2. Produce more than half of the
oxygen in the atmosphere, and
absorb the most carbon from it.
3. Ocean waters serve as a source
of food and valuable minerals.
Coral Reefs
Close to equator
Shallow water
Coral reefs buffer adjacent shorelines
from wave action and prevent erosion
biodiversity is considered the key to
finding new medicines for the 21st
century
Waves along the shoreline are
constantly eroding,
transporting and depositing
sediment.
Shorelines
a. Shoreline weathering 1. Wave impact
Water pounding on the
shore
Large waves, high
energy & lots of force
2. Abrasion
Sawing & grinding
action of rock
fragments in water
b. Shoreline erosion Wave refraction
Bending of waves.
(Waves slow down and
curve as they approach
the shore.)
3. Longshore transport
When currents flow parallel
to the shore moving large
amounts of sediment
****Longshore currents result primarily from the curved
approach of waves towards the beach (refraction).
Movement of water along the shore creates water currents
that move sediment parallel to the beach.
Longshore current= movement of water along the shore
Longshore drift= movement of sediment along the
shoreline
c. Longshore Movement
Coastal landforms that form as a
result of erosion by waves
d. Shoreline Erosional
Features
1. Wave-cut cliffs
& platforms:
formed by
waves slowly
wearing away
coastal land
2. Sea arches & stacks: softer parts of headland eroded away by waves
e. Depositional Features
Result of beach sediment being transported
along the shore and deposited where wave
energy is low
1. spit: long, narrow deposit of sand connected at one end to the shore
end might hook in response
to the dominant direction of
the longshore current
The formation of a spit by sand movement in response to longshore
currents.
2. Baymouth
Bar
sand bar that completely
crosses a bay, sealing it off
from open ocean
3.Tombolo
ridge of sand that connects an
island to the mainland or
another island
4.Barrier Islands
narrow sand bars parallel to, but separated from, the coast at distances from 3-30 km offshore
Barrier Islands can be a hazardous place to live because of severe erosion during storms
THREATS TO THE MARINE
BIOME
a. Threats to
the Oceans
1. Pollution
2. Overfishing
3. Poor fishing methods
4. Destruction of fishing grounds
http://www.worldbiomes.com/biomes_aquatic.htm
b. Threats to the Coral
Reefs
1. Temperature is important,
If it is too hot or too cold,
the animals can’t live there
to create limestone
(CaCO3)
2. Human intrusion (scuba
diving) is damaging if you
touch/step on the reef
3. Pollution
4. Ocean Acidification
5. Loss of Biodiversity
www.calacademy.org
c. Human Impact on Marine
Shorelines
Protective Structures
Humans have developed techniques to
stabilize shoreline erosion through the use of
HARD STABILIZATION STRUCTURES and
beach nourishment.
1. Groins
structure that is built perpendicular to a beach to prevent sand from moving
2. Seawall
built parallel to shore
to protect property
from breaking waves
3. Breakwater
structure build parallel to shore to
create a “quiet zone” between the
shore and the open ocean; used to
protect boats from large, breaking
waves
4. Beach Nourishment
adding additional sand to a beach to
replace sand that has been washed
away; alternative to building
protective structures
