NIVEAU AVANCÉ DU SUPPLÉMENT SONORE
Shelly reçoit le Dr Emma Camp, experte en biologie marine, qui partage avec elle les secrets de la Grande Barrière de Corail. CD audio ou téléchargement MP3 (sur abonnement)
rubble around reefs could also help create space for new corals to grow, and is another area under investigation. Modelling for the program found these approaches tended to only be cost effective if emissions in the future were very low. But they could still help at smaller scales.
11. Anthony says if temperatures stay below 2C “then there is so much we can do” across all the approaches. “It’s both daunting to look at the challenge ahead, but also we know we have to come up with a plan,” he says. “At 3C the reef will look very different – it would be a sad story, but you still wouldn’t give up.” rubble débris / to grow, grew, grown pousser / area ici, possibilité / cost effective rentable / still ici, malgré tout. 11. daunting impressionnant, effrayant / ahead devant; ici, qui nous attend / to come, came, come up with concevoir / to give, gave, given up abandonner, renoncer.
TRANSPORTING CORALS AND LARVAE
12. Prof Peter Harrison, at Southern Cross University, is a global expert on how corals reproduce and was among the first to discover their mass spawning on just a few nights of the year after full moons. “It’s like an underwater snowstorm and billions of eggs and sperm get released,” he says. One approach under development is to find ways to capture larvae during natural spawning and then move them in “slicks” and drop them in places that need help to recover.
13. Harrison says there is always masses of excess coral larvae that would float away or be eaten and, before the impacts of climate change, “it didn’t matter if 99% [of the larvae] drifted away or got eaten by fish, because there were so many of them.” “Because the production of larvae has been so dramatically impacted because of the mass bleaching, we are now looking to see how we could use what we know about coral reproduction and more effectively transfer them onto damaged reef systems.”
14. Harrison says methods being researched under the new program include scaling up floating ocean pools to transfer coral larvae, or eggs and sperm raised in aquaculture ponds, onto reefs. Corals get much of their colour and nutrients from the symbiotic relationship they have with special algae. Harrison says that some corals are more heat tolerant than others, and the same goes for the algae.
15. Combining heat tolerant algae and heat tolerant corals, and then producing more heat tolerant larvae, could give reefs “more scope for growth under warming conditions”. “We think we can get an increased tolerance [of corals] of just a few degrees. Ultimately, unless the political leadership around the world enables a realistic approach to managing greenhouse gas emissions and bringing the rate of climate change under control, the system will become so overwhelmed we won’t be able to use these corals.
16. “We are buying time to help coral species to evolve and adapt and buy enough time to get some real action on climate change. There’s a large group of people around me who feel we can’t wait for action. We have to work out what we can do now.”