Ecosystems-coral reefs

Question 1

tell me about physical influences on coral reef-warm seas

Answer 1

-causes coral bleaching
-in Jamacia, coral bleaching is significant when sea temp is above 29.3
-in Jamacia (2005) sea surface temps high and 34% of coral bleached on average

Question 2

tell me the Jamaican reef location

Answer 2

-coral reef area=1,240km2
-along most of the north and east coast
-on neighbouring banks within Jamaica’s EEZ

Question 3

how quickly does coral grow?

Answer 3

1-100cm per year

Question 4

tell me about physical influences on coral reefs-disease epidemic

Answer 4

-disease epidemic swept through populations of important reef grazers & led to mass mortality across the Caribbean
-sea urchin populations declined 99%
-lack of fish & urchins meant there was rapid algae growth
-these limit the sunlight available & cause lack of oxygen in water
-when oxygen levels decline, marine animals, corals reefs and other vital habitants suffer and may die

Question 5

Tell me about human prevention methods in Jamaica

Answer 5

• humans can help by setting up marine protected areas such as underwater national parks
• fishing can be forbidden
• This allows reefs to recover
• Can seed nearby areas with coral larvae
• Will slow down decline

Question 6

Tell me the physical influences on coral reefs- hurricanes

Answer 6

• violent waves fragment and kill Corals in Shallow water
• corals are damaged by objects being tossed around in waves

Question 7

Tell me about human influences in coral reefs- chemicals in Jamcia

Answer 7

• in recent years there’s been water sohortage in Jamaica
• been calls for the building of desalination plants on the island
• These plants remove all the unwanted chemicals from water and produce a freshwater supply
• unwanted chemicals are flushed into the sea which causes localised increase in salinity and temp
• causes widespread alternations to community structure in reefs when discharges are released in areas where there’s little mixing of sea water

Question 8

Tell me about Human influences on coral reefs-pollution

Answer 8

• comes in many forms, including onshore development such as bauxite mining, which is particularly important for Jamaica’s economy
• This activity releases large quantities of sediment that can be deposited in marine areas
  -The processes of excavating, removal of top soil and vegetation, transportation of bauxite and unwanted elements, cause degradation of air quality mainly related to dust pollution
  -Coral reefs need clean, clear water to survive.
  -When sediment and other pollutants enter the water, they smother coral reefs, speed the growth of damaging algae, and lower water quality.
  -Pollution can also make corals more susceptible to disease, impede coral growth and reproduction, and cause changes in food structures on the reef.

Question 9

Tell me about Jamaica’s overfishing

Answer 9

• the fish population on Jamaica reefs have been steadily declining as a result of overfishing
• one study indicated that fish biomes have already been reduced by up to 80% since the late 1970s
  -decline of fish species leads to booms in organisms such as phytoplankton
  -these take up oxygen from other forms of life leading to the decline in coral

Question 10

Tell me some characteristics of coral reefs

Answer 10

• 30° north and south of the equator
• surface temp 23° C-27°C
• composed of calcium, carbonite and limestone

Question 11

Tell me about the effect of climate change on coral reefs

Answer 11

• the warming atmosphere heats up the oceans causing increased coral bleaching
• further increases in dissolved CO2 will make the oceans more acidic depleting the carbonate ions that the corals need

Question 12

Tell me about the cultural value of coral reefs

Answer 12

• education and research
• reefs are easily accessible from the shore

Question 13

Tell me about ecological value of coral reefs

Answer 13

• protection for the coastline breaks power of waves before reaching land
• highly diverse ecosystem

Question 14

Tell me about the economic value of coral reefs

Answer 14

• aquamarine trade
• medicine- algae and sponges contain bioactive compounds used by the pharmaceutical industry
• building materials - minend for limestone
• tourism- some Caribbean countries gain a half of their GDP from tourism

Question 15

Tell me about the future prospect for coral reefs

Answer 15

• coral reefs are being collapsed and replaced by algae
• In Jamaica-proportion of the reef covered by live coral has fallen from 50% in the 1970s to 8% in 2013 which changes fish communities
• people suffer. More than 450 million people live close to reefs and rely on them as sources of tourism, revenue and protein. And as buffers that dampen the energy of the incoming storms

Question 16

Tell me about coral adaptations

Answer 16

• some corals have genetic advantages that allow them to thrive in shallower warmer waters
• corals can climatize to change in conditions and there is some evidence that corals which bleach extensively for one year are better able to handle warmer waters a decade later
• refs can shift from sensitive species(elkhorns)to robust ones ( boulder coral)

Question 17

Tell me about the Great barrier reef and adopting coral

Answer 17

• reef restoration foundation programs sees coral growth in an underwater nursery from finger size corals to large scale coral colonies
• for £50 you can join the coral crusade and adopt one
• planting 25,000 new corals in the Great barriers in 2021
• After 6 to 12 months of growing under the careful care of scientist and volunteers, the coral graduates from the nursery and a reattached to the reef

Question 18

explain the negative impact of gases on coral reefs

Answer 18

-increased gases from burning fossil fuels enter oceans- this turns them into acids (ocean acidity)
-this makes limestone dissolve more easily

Question 19

why are blooms of algae bad?

Answer 19

-they soak up oxygen (eutrophication)
-block sun light

Question 20

tell me about polyp

Answer 20

-these are the tiny organisms which, together, form coral reefs
-they settle on rocks and produce limestone beneath them
-groups of polys link up to become less vulnerable

Question 21

tell me about the symbiotic relationships between algae and coral

Answer 21

-algae gives coral 90% of the corals total food intake
-if algae becomes separated from coral (coral bleaching) the coral will starve

Question 22

tell me about bio rock

Answer 22

-this is a preservation method
-low voltage electrical currents are ran through a steel frame
-this allows calcium carbonate to crystalise on the surface
-this creates more places for coral to grow