Meet the super corals that can handle acid, heat and suffocation

Resilient corals are offering hope for bleached reefs.
Emma Camp

Emma F Camp, University of Technology Sydney and David Suggett, University of Technology Sydney

Climate change is rapidly changing the oceans, driving coral reefs around the world to breaking point. Widely publicised marine heatwaves aren’t the only threat corals are facing: the seas are increasingly acidic, have less oxygen in them, and are gradually warming as a whole.

Each of these problems reduces coral growth and fitness, making it harder for reefs to recover from sudden events such as massive heatwaves.

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Read more:
Acid oceans are shrinking plankton, fuelling faster climate change

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Our research, published today in Marine Ecology Progress Series, investigates corals on the Great Barrier Reef that are surprisingly good at surviving in increasingly hostile waters. Finding out how these “super corals” can live in extreme environments may help us unlock the secret of coral resilience helping to save our iconic reefs.

Bleached coral in the Seychelles.
Emma Camp, Author provided

Coral conservation under climate change

The central cause of these problems is climate change, so the central solution is reducing carbon emissions. Unfortunately, this is not happening rapidly enough to help coral reefs, so scientists also need to explore more immediate conservation options.

To that end, many researchers have been looking at coral that manages to grow in typically hostile conditions, such as around tide pools and intertidal reef zones, trying to unlock how they become so resilient.

These extreme coral habitats are not only natural laboratories, they house a stockpile of extremely tolerant “super corals”.

What exactly is a super coral?

“Super coral” generally refers to species that can survive both extreme conditions and rapid changes in their environment. But “super” is not a very precise term!

Our previous research quantified these traits so other ecologists can more easily use super coral in conservation. There are a few things that need to be established to determine whether a coral is “super”:

1. What hazard can the coral survive? For example, can it deal with high temperature, or acidic water?

2. How long did the hazard last? Was it a short heatwave, or a long-term stressor such as ocean warming?

3. Did the coral survive because of a quality such as genetic adaption, or was it tucked away in a particularly safe spot?

4. How much area does the coral cover? Is it a small pocket of resilience, or a whole reef?

5. Is the coral trading off other important qualities to survive in hazardous conditions?

6. Is the coral super enough to survive the changes coming down the line? Is it likely to cope with future climate change?

If a coral ticks multiple boxes in this list, it’s a very robust species. Not only will it cope well in our changing oceans, we can also potentially distribute these super corals along vulnerable reefs.

Some corals cope surprisingly well in different conditions.
Emma Camp, Author provided

Mangroves are surprise reservoirs

We discovered mangrove lagoons near coral reefs can often house corals living in very extreme conditions – specifically, warm, more acidic and low oxygen seawater.

Previously we have reported corals living in extreme mangroves of the Seychelles, Indonesia, New Caledonia – and in our current study living on the Great Barrier Reef. We report diverse coral populations surviving in conditions more hostile than is predicted over the next 100 years of climate change.

Importantly, while some of these sites only have isolated populations, other areas have actively building reef frameworks.

Particularly significant were the two mangrove lagoons on the Great Barrier Reef. They housed 34 coral species, living in more acidic water with very little oxygen. Temperatures varied widely, over 7℃ in the period we studied – and included periods of very high temperatures that are known to cause stress in other corals.

Mangrove lagoons can contain coral that survives in extremely hostile environments, while nearby coral reefs bleach in marine heatwaves.
Emma Camp, Author provided

While coral cover was often low and the rate at which they build their skeleton was reduced, there were established coral colonies capable of surviving in these conditions.

The success of these corals reflect their ability to adapt to daily or weekly conditions, and also their flexible relationship with various symbiotic micro-algae that provide the coral with essential resources.

While we are still in the early phases of understanding exactly how these corals can aid conservation, extreme mangrove coral populations hold a reservoir of stress-hardened corals. Notably the geographic size of these mangrove locations are small, but they have a disproportionately high conservation value for reef systems.

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Read more:
Heat-tolerant corals can create nurseries that are resistant to bleaching

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However, identification of these pockets of extremely tolerant corals also challenge our understanding of coral resilience, and of the rate and extent with which coral species can resist stress.

Emma F Camp, DECRA & UTS Chancellor’s Research Fellow, Climate Change Cluster, Future Reefs Research Programe, University of Technology Sydney and David Suggett, Associate Professor in Marine Biology, University of Technology Sydney

This article is republished from The Conversation under a Creative Commons license. Read the original article.

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Ultra, super, clean coal power? We’ve heard it before

Marc Hudson, University of Manchester

Replacing old coal power stations with new “ultra-supercritical” stations could help meet Australia’s greenhouse gas targets, according to research commissioned by Resources Minister Matt Canavan. Other analysts have reacted with scepticism.

Echoing recent prime ministers, Canavan retorted that these criticisms were part of an “ideological” attack on coal:

Coal has an important role to play as Australia and the rest of the world reduce carbon dioxide emissions… Australia has the resources to be a low-cost and efficient energy superpower. Access to affordable and reliable power underpins our economy and is the key to long-term jobs in the manufacturing sector.

This is not the first time Canavan has put his weight behind increasing Australia’s coal production to “help the environment”.

But technological promises and government support for coal’s bright future stretch back almost 40 years, long before the election of Tony “coal is good for humanity” Abbott, and have been entirely bipartisan, as have claims that Australian coal is especially clean.

Early days

The NSW was funding “supercoal” research for air-pollution reasons from the early 1980s. Climate change entered the fray in 1988, when delegates at the Australian Coal Association conference were told:

Coal’s contribution to the greenhouse effect is small… Means of controlling C0₂ emissions from coal-fired plant are considered best achieved by improved overall operating efficiency using new technology, rather than by endeavouring to capture C0₂ emissions.

The early Labor advocate of climate action, Graham Richardson, told a reporter in July 1989:

Fortunately we use mostly – but not entirely – the cleanest coal in the world. But that doesn’t mean we can’t improve the technology and so limit how much carbon dioxide is blown up the spout.

(Times change; Richardson recently called on Opposition Leader Bill Shorten to recant on his “silly” green goals.)

The same year the visiting president of the US National Coal Association told a government committee that, while much of the low-emissions technology was still in the laboratory stage, he was confident it could be applied soon to plants using coal to produce energy.

In 1991 Australian government funds supported an international conference on clean coal in Sydney.

After Australia’s first climate policy, the National Greenhouse Response Strategy, was agreed in December 1992, it quickly became clear that the Commonwealth was not going to stand in the way of state-level support for new coal-power stations.

On March 21 1994, the UN Framework Convention on Climate Change became international law. Coincidentally, Singleton Council in New South Wales approved a new coal-fired power station. Greenpeace launched a legal challenge, but this failed in November 1994. The State Electricity Commission of Victoria’s greenhouse reduction plans died with privatisation.

Peak (clean) coal

It is debatable, but Labor perhaps had more concern – for both climate change and coalminers’ jobs – than the incoming Howard government. The Prime Minister’s Science Engineering and Innovation Council in 1999 suggested Australia ratify the Kyoto Protocol and see it as an opportunity and spur to new technologies.

This fell on John Howard’s deaf ears, but a December 2002 report, chaired by Rio Tinto’s chief technologist and government chief scientist Robin Batterham, was taken up, and the enthusiasm for carbon capture and storage (CCS) was born. A COAL21 plan followed in 2004, and the Australian Coal Association Low Emissions Technologies group was formed.

Howard’s enthusiasm for coal over renewables was such that he even called a “secret” meeting of fossil fuel producers to advise on lower emissions technologies.

The 2004 Energy White Paper continued the trend in support for CCS over renewables.

Labor’s innovation in 2007 was to say yes to both. As opposition leader, Kevin Rudd announced he would bring in a National Clean Coal Centre.

Had the Coalition won the 2007 election, it would have removed the Renewable Energy Target and replaced it with a scheme that would have allowed coal-with-CCS to be considered “low carbon”.

In 2008 the coal association spruiked “NewGenCoal” in television adverts.

It all started to go wrong in 2009, shortly after the launch of the expensive and controversial Global Carbon Capture and Storage Institute, Rudd’s brainchild.

Former Liberal minister Ian MacFarlane, who had previously urged the coal industry to sell its message, told ABC’s Four Corners:

The reality is, you are not going to see another coal-fired power station built in Australia. That’s, that’s a simple fact. You can talk about all the stuff you like about carbon capture storage, that concept will not materialise for 20 years, and probably never.

Geology intervened as the Queensland ZeroGen project ended in late 2010, when the state government decided to stop throwing taxpayers’ money at it.

And in 2013 it emerged that the coal association’s funding for low-emissions technologies had been broadened to include “promoting the use of coal”.

While there is now a functioning CCS plant in Canada, in Australia CCS limps on and the sums involved now are pitifully small.

Dark days ahead

Three concepts from the study of technological innovation may help us understand what is going on.

The first is the “hype cycle” – the observation that initial unrealistic enthusiasm for a shiny new technology goes up like a rocket and down like a stick, followed by a more gradual, tempered enthusiasm over time (for a recent appraisal see here).

The second is the sailing ship effect. When challenged by steamships, the incumbent technology added more sails, automated sailors and so on, trying to keep up. But ultimately it was in vain – a new technology won out.

Thirdly, supporters of incumbent technologies highlight teething problems in the challenger technologies, in what academics call “discursive battles”.

It’s fair to guess three things. Promises of clean coal, high-efficiency, low-emissions (HELE) coal power and bio-energy carbon capture and storage(BECCS) will escalate, but perhaps learning from the public mockery of the last two efforts – Australians for Coal and Little Black Rock.

Protests, by people who agree with James Hansen’s 2009 assessment that coal-fired power stations are death factories, will continue. Legal challenges will escalate.

Governments – state and federal – will keep wrestling with the greased pig that is the “energy trilemma”. 2017 will be bloody, and noisy.

Marc Hudson, PhD Candidate, Sustainable Consumption Institute, University of Manchester

This article was originally published on The Conversation. Read the original article.

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