Coastal ecosystems

Question 1

Biome -

Answer 1

is a global ecosystem that shares the same climate (coral reefs; mangroves)

Question 2

Habitat zone -

Answer 2

is a local ecosystem (salt marshes; sand dune)

Question 3

Coral reefs need (5 things):

Answer 3

• warm tropical water (23-28 degrees)
• shallow
• salinity 36
• very clean water
• the edge of the continental shelf

Question 4

Abiotics -

Answer 4

factors that are created by non-living chemical and physical.

Question 5

Food chain vs Food web

Answer 5

Food chain - flow energy

Food web - who eats who

Question 6

The Great Barrier Reef threats

Answer 6

Tourism -> diving, unexperienced divers step on the corals and destroy them
Port -> oil spills which leads to a contaminated water that corals can’t live in
Coal -> mining and eventual burning of this coal generate huge amount of CO2, which accelerates global warming
Agriculture -> pollutants from the agriculture decrease the quality of water
Hotels -> sewage

Question 7

Management of the Great Coral Reef (3 things to mention)

Answer 7

1) International
It is declared a UNESCO world heritage, which give the reef legal protection against any new developments. Many species have been put on the red list.

2) National strategy
The marine park is managed by the marine park authority. They allow activities but educate the companies or groups of people to be environmentally friendly.

3) Local management
The non-government organisations work with local people to reduce the environmental issues/impact of human activity. They count the number of species numbers, which can help decied which areas to protect.

Question 8

Mangroves -

Answer 8

are trees that grow in a sub-tidal area.

Question 9

Threats to mangroves (4 things to mention)

Answer 9

1) Sea level rise
Global warming -> melting of glaciers -> sea level rises -> salt water incursion

2) Shrimp farming
The mangroves are cleared to make lagoons for shrimp farmers

3) Rise farming
The mangroves are cleared to grow rice plants. Chemical fertilizers are used which pollute the water

4) Building of dams
Mangroves grow in mud, which is supplied by the river. If the dam is built, it stops a mud flow, which leads to a decrease of mangroves

Question 10

Salt marshes -

Answer 10

A salt marsh is an area of mud that has been colonised by plants

Question 11

Threats to salt marshes

2 natural threats and 2 human

Answer 11

1) Storms
The high waves can erod the coastline

2) Climate change
as the sea temperature increases, thermal expansion leads to sea level rise, flooding salt marsh

1) Agricultural pollution
run of nitrates and phosphates into the salt marsh can increase the algae and decrease other plant species

2) Sea wall
If there’s a road, railway, sea wall behind the salt marsh, sea level rise lead to the ‘squeezing’ of the salt marsh.

Question 12

Sand dunes formation -

Answer 12

Embryo dune:
Pioneer plants grow and trap more sand

Yellow dune:
Narrow grass can grow as the dune is more stable. When the grass dies it adds organic matter (humus) which traps moisture

Grey dune:
The organic matter decreases the sand and has water which allows new plants to grow. They outcompete the smaller plants.

Question 13

Threats to sand dunes (3 things to mention)

Answer 13

1) Trampling
lower biodiversity as the plants are eroded

2) Climate change
sea level rise -> more erosion of the embryo dunes

3) coastal development