The reef and beyond
changes on the reef
oceans of the future
managing fisheries
miscellaneous
100
When did the formation of the GBR stabilise due to stabilisation is sea levels?
6500 years ago
100
changes in the environment caused by humans
anthropogenic
100
identify two weather patterns in Australia associated with La Nina
wetter (flooding)
more cyclones
cooler
fewer temperature extremes
100
what are the three main types of fisheries?
artisanal
recreational
commercial
100
arrange in the correct sequence:
planula, polyp, gamete, zygote
polyp >gamete>zygote>planula (>polyp)
200
the family name of the reef forming corals
Scleractinia
200
what is the name of the "balancing" of carbonate, bicarbonate and carbonic acid in the oceans?
carbonate buffering system
200
give two differences between the responses of government or non government organisations
speed
diplomatic constraints
political influence
enforceability
200
What is MSY?
the maximum sustainable yield - the number of fish that can be harvested without reducing the population
200
Determine the stock size if the number initially marked is 48, the number in the second capture is 20 and the number of marked in the second capture is 5
192
300
which reef zone has the greatest biodiversity?
reef slope or reef front
300
what happens to the amount of CO2 dissolved in sea water as you get deeper? why
it increases, because the water is getting colder - cold water dissolves more gas
300
explain how the temperature difference between land and sea can produce onshore or offshore breezes
day: land is hot, water is cooler, hot air rises, cooler air from the sea replaces it (onshore breeze)
night: land is cold, water is warmer. creates an offshore breeze
300
what is the formula for Lincoln index, and what do the letters stand for?
N = M x n/m
N=total number of organisms
M= total number of marked organisms
n=number in the second capture
m= number of marked in the second capture
300
what is FCR?
feed conversion ratio - how much feed is given to the fish for a certain mass gain
400
Why do polyps withdraw their tentacles in the day and extend them at night (two reasons)
- more food (zooplankton) available at night
- fewer predators to nibble on them
400
describe the process of ocean acidification in terms of the concentration of hydrogen ions and availability of carbonate ions (3 steps)
carbon dioxide dissolves in water to form carbonic acid
carbonic acid dissociates to release H+ ions
decreased pH reduces availablity of CO3 ions
400
recall two arguments for preserving species and habitats
ecological
economic
aesthetic
ethical
400
describe how fish populations are determined by one of: temperature, primary productivity, currents, upwelling
answer
400
identify two attributes which make a good aquaculture species
fast life cycle, high reproduction rate
low feed conversion ratio
resilience
marketability
500
explain how water quality factors can reduce coral cover due to crown of thorns outbreaks (3 points)
increased run-off increases the nutrients in the water, this increases the amount of phytoplankton. phytoplankton is COTS larval food, so an increase in COTS larvae, results in an increase of COTS adults
500
how will ocean acidification affect marine food chains (with reference to coccolithophores)
coccolithophores have calcium carbonate shells
OA will reduce availability of CO3, and so make the shells weaker
coccolithophores will be less abundant - less food for zooplankton, disrupts food chain
500
identify two management strategies used to support marine ecosystem health
managing threats
zoning
permits
plans
longitudinal monitoring
500
what is the difference between an open and a closed aquaculture system in terms of waste management?
open - waste is removed by currents directly into the environment
closed - water is pumped and cleaned through filters before being put back in the tank
500
why is a higher proportion of seafood consumed in australia is imported than locally grown?
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