Section 2 Marine Ecosystems
Where are marine ecosystems located?
ª
Mainly coastal areas and in the open ocean
What do organisms that live along coastal areas adapt to?
ª
Changes in water level and salinity
What do organisms that live in the open ocean adapt to?
ª
Changes in temperature and the amounts of
sunlight and nutrients avaialable
Coastal Areas
What are coastal wetlands?
ª
Coastal land areas that are covered by salt
water for all or part of the time
What do coastal wetlands do?
ª
Provide habitat and nesting areas for many fish
and wildlife, absorb excess rain (protecting areas from floods), filter out
pollutants and sediments, provide recreational areas for boating, fishing, and
hunting
Estuaries
What is an estuary?
ª
An area in which fresh water from a river mixes
with salt water from the ocean
How does a mineral-trap form?
ª
As two bodies meet, currents forma nd
mineral-rich mud and other sediment fall to the bottom
Why are estuaries productive?
ª
Constantly receive fresh nutrients from the
river and from the ocean
Plants and Animals of Estuaries
Why do estuaries support many marine ecosystems?
ª
Receive plenty of sunlight and plenty of
nutrients
What do the light and nutrients support?
ª
Large populations of rooted plants as well as
plankton
Why are plankton important?
ª
Provide food for larger animals, such as fish
Why are organisms of estuaries able to tolerate variations
in salinity?
ª
Salt content of water varies as freshwater and
saltwater mix when tides go in an out
What do estuaries provide?
ª
Protected harbors, access to oceans, connection
to rivers
What are the 6 large urban areas built on estuaries?
ª
Tokyo, New York, Shanghai, Buenos Aires, Rio de
Janeiro, Bombay
Threats to Estuaries
Where were estuaries developed as building sites?
ª
California
What pollutants damage estuaries?
ª
Sewage, industrial waste containing toxic
chemicals, agricultural runoff of soil containing pesticides and fertilizers
Salt Marshes
Where are salt marshes found?
ª
Shoreline of the Gulf of Mexico and the Atlantic
Coast of the US
Where do salt marshes develop?
ª
In estuaries where rivers deposit their load of
mineral-rich mud.
What animals use salt marshes as a nursery?
ª
Shrimps, crabs, and fishes
What do salt marshes absorb?
ª
Pollutants
Mangrove Swamps
Where are mangrove swamps located?
ª
Coastal areas of tropical and subtropical zones
What do mangrove swamps protect?
ª
Coastline from erosion and reduce the damage
from storms
How many animals use mangrove swamps for breeding and
feeding grounds?
ª
2,000
Rocky and Sandy Shores
Which has more plants and animals and why?
ª
Rocky, rocks provide anchorage for seaweed and
many animals that live on them
Where are barrier islands found and what do they do?
ª
Islands that run parallel to the shore, help
protect the mainland and the coastal wetlands
Coral Reefs
Where are coral reefs found?
ª
Warm, shallow tropical seas where there is
enough light for photosynthesis
What are coral reefs?
ª
Limestone ridges built by tiny coral animals
called coral polyps
How do coral reefs form?
ª
Coral polyps secrete skeletons of limestone
(calcium carbonate), which slowly accumulates and form coral reefs
Where are living corals found?
ª
Only on the outer layer of the coral reef
What type of organisms are coral and how do they get their
food?
ª
Predators, use stinging tentacles to capture
small animals, such as zooplankton, that float or swim close to the reef
Disappearing Coral Reefs
What % of coral reefs are in danger?
ª
27
What things may damage or destroy coral reefs?
ª
Water is too hot or too cold or freshwater
drains into the area surrounding reef.
If water is too muddy, polluted, or is too high in nutriments
How can over-fishing affect coral reefs?
ª
Devastate the fish population which upsets
balance of reef ecosystem
How can people damage coral reefs directly?
ª
Careless divers, fisheries, shipwrecks, ships
dropping anchors, people breaking off for decorative items or for building
materials
Oceans
How deep does sunlight penetrate into the ocean?
ª
100 meters or 330 feet
Where is most ocean life concentrated?
ª
Shallow, coastal areas
Plants and Animals of Oceans
Where do phytoplankton grow in the open ocean?
ª
Areas where there is enough light and nutrients
What is the least productive of all ecosystems?
ª
Open ocean
What do phytoplankton have that stops them from sinking?
ª
Buoyancy devices, such as whip-like flagella to
stop them from sinking into deep water
What are zooplankton and give examples?
ª
Small herbivores that eat phytoplankton –
jellyfish, tiny shrimp, and the larvae of fish and bottom dwelling animals such
as oysters and lobsters
What feed on plankton?
ª
Fish and marine mammals such as whales
Where does food of the deep ocean come from?
ª
Dead organisms that fall from the surface
What organisms are found in the deep ocean?
ª
Decomposers, filter feeders, and other organisms
that eat them
Threats to the Ocean
Where does most ocean pollution arises from where?
ª
Activities on the land
What is the biggest source of coastal pollution?
ª
Industrial waste and sewage discharged into
rivers
How does fishing affect ocean organisms?
ª
Trawl nets entangle organisms and marine mammals
can drown, discharge fishing lines into the ocean, which can strangle and kill
fish and seals
Arctic and Antarctic Ecosystems
Why do the North and South Pole depend on marine ecosystems?
ª
Nearly all food comes from them
Why is the Arctic Ocean important?
ª
Rich in nutrients from surrounding landmasses,
and supports large populations of plankton, which feeds a large diversity of
fish
What is the only continent never colonized?
ª
Antarctic
What is the Anatarctic used for and who governs it?
ª
Mainly for research, international commission
What animals are found in the Antarctic?
ª
Fish, whales, birds such as penguins
