Thursday, November 6, 2014
How corals can actually benefit from climate change effects
Researchers from Northeastern University's Marine Science Center and the University of North Carolina at Chapel Hill have found that moderate ocean acidification and warming can actually enhance the growth rate of one reef-building coral species. Only under extreme acidification and thermal conditions did calcification decline.
Their work, which was published Wednesday in the journal Proceedings of the Royal Society B: Biological Sciences, is the first to show that some corals may benefit from moderate ocean acidification.
The authors attribute the coral's positive response to moderately elevated carbon dioxide to the fertilization of photosynthesis within the coral's algal symbionts, which may provide the coral with more energy for calcification even though the seawater is more acidic. They propose that the eventual decline in coral calcification at the very high levels of carbon dioxide occurs when the beneficial effects of fertilizing photosynthesis are outweighed by the negative effects of acidification on the skeleton-forming process.
"The study showed that this species of coral (Siderastrea siderea) exhibited a peaked or parabolic response to both warming and acidification, that is, moderate acidification and warming actually enhanced coral calcification, with only extreme warming and acidification negatively impacting the corals," Ries said. "This was surprising given that most studies have shown that corals exhibit a more negative response to even moderate acidification."
Furthermore, their work indicates that ocean warming is likely to threaten this coral species more than acidification by the end of the century, based on projections from the Intergovernmental Panel on Climate Change.
He noted that in the past 200 years, ocean pH level has dropped from 8.2 to 8.1 and is expected to fall even further to about 7.8 over the next one or two centuries. That is a significant decrease over a relatively short period of time, Ries said, when looking at the geologic history of ocean acidification.
"The amount of change that would typically occur in about 10 million years is being condensed into a 300-year period," Ries said. "It's not the just the magnitude of the change that matters to the organisms, but how quickly it is occurring."
"Acidification of the surrounding seawater is certainly important for marine organisms, but what is equally as important—perhaps even more important—is how the chemistry of their internal calcifying fluid responds to these changes in seawater chemistry," Ries said.
Tuesday, August 12, 2014
Panic about the reef is a hardy perennial; I remember it from 50 years ago. But coral recovers quickly from damage. The Greens would only be happy if all human influences were removed
Two major reports into the health and management of the Great Barrier Reef have found parts of the World Heritage site are still under pressure and the central and southern areas are deteriorating.
Federal Environment Minister Greg Hunt today released a strategic assessment and a five-yearly outlook for the reef.
The United Nations' World Heritage Committee is concerned about the Abbot Point port expansion and the plan to dump of three million cubic metres of dredge spoil within the marine park.
It is due to decide next year whether to list the reef as a World Heritage site "in danger".
The outlook report, prepared by the Great Barrier Reef Marine Park Authority (GBRMPA), found the health of the reef was still worrying compared to its last report five years ago.
"Even with the recent management initiatives to reduce threats and improve resilience, the overall outlook for the Great Barrier Reef is poor and getting worse," the authority's chairman Russell Reichelt wrote.
While pollutants entering the reef had measurably reduced since 2009, the greatest risks have not changed.
They include climate change, farm run-off, coastal developments and fishing.
In recent years, a series of major storms and floods have affected an ecosystem already under strain, and the accumulation of all impacts had the potential to further weaken its resilience.
"This is likely to affect its ability to recover from series disturbances, such as major coral bleaching events, which are predicted to become more frequent," the report said.
"The Great Barrier Reef is an icon under pressure.
"Without promptly reducing threats, there is a serious risk that resilience will not be improved and there will be irreversible declines in the region’s values.”
The report found the northern third of the region has good water quality and its ecosystem was in good condition.
However, the habitat, species, and ecosystem in the central and southern inshore areas had continued to deteriorate because of human use and natural disasters.
The dugong population, which was already at very low levels, had declined further in those areas.
Overall, some species were rebounding, including humpback whales, estuarine crocodile and loggerhead turtles.
Hunt confident reef won't be listed as 'in danger'
Federal Environment Minister Greg Hunt said there had been some improvements, but there needed to be more.
"The report is a mixture of pressure and progress," he said.
"In the south, there were some real negatives, to be honest. Now is the moment that we have to turn around the reef."
He said he was confident the Government would do enough to save the reef from being listed "in danger", including reducing port developments.
"It was put on the review list on somebody else's watch," he said. "Our task is to not just remove it from the watch list, but to make sure the reef recovers to its former glory."
Environmentalists want the Government to commit billions to reduce water pollution.
WWF-Australia CEO Dermot O'Gorman said billions were being spent to save the Murray River, and the reef needed the same commitment.
"Australians are deeply concerned that our national icon is dying on our watch," he said.
Tuesday, June 3, 2014
Coral reefs are better at coping with rising sea temperatures than we thought
Coral reefs are under threat from rising sea temperatures caused by global warming. But in a recent paper, published in Science, it was found that certain types of coral are able to adapt to tolerate higher sea temperatures by changing the genes they express. Scientists think this new discovery could be used to devise new ways of protecting coral reefs, as well as improving our predictions of how they will cope with climate change in the future.
Known as the "rainforests of the sea," coral reefs form some of the most diverse ecosystems on earth. Despite only covering 0.1 percent of the ocean's surface, they provide a home for 25 percent of all maritime species, including fish, mollusks, and sponges.
Coral reefs are actually deposits of calcium carbonate, the substance found in sea shells. The makeup of any coral reef is complex and consists of microscopic organisms called corals that live together in small colonies known as polyps. Polyps that contain "reef building" coral species are responsible for laying down the calcium carbonate that form the reefs. Corals live together with algae, and this relationship helps coral reefs survive.
But when coral reefs experience stress, such as an increase in sea temperature, they sometimes expel the algae, which results in coral bleaching, a phenomenon in which the coral loses all its color, appearing completely white. This can result in the death of the reef. For example, in 2005, the US lost half of its coral reefs in the Caribbean to a massive bleaching event.
It is already known that some corals are better than others at coping with stress. So Professor Stephen Palumbi and his colleagues at Stanford University in California set out to assess whether coral species have the ability to acclimate to warmer temperatures by increasing their thermal tolerance levels.
Palumbi and his team completed their fieldwork on coral reefs in the U.S. National Park of American Samoa on Ofu Island. They concentrated on an important reef-building coral species. The corals were contained in two adjacent pools. In the first pool, water temperatures were more varied, reaching temperatures as high as 35°C. This was known as the highly variable pool. The second pool, known as the moderately variable pool, rarely experienced water temperatures of above 32°C.
First, the researchers tested the photosynthesis rates of corals from both pools to compare how well they coped with high temperatures. They then transplanted coral colonies from the moderately variable pool to the highly variable pool to see if the coral would adapt to higher water temperatures. The transplanted corals were left to acclimate over the course of about two years, and were regularly tested for thermal tolerance over this time. The researchers conducted genetic analysis to see if there was any change in gene expression during this period that would result in higher thermal tolerance.
It was found that corals in the highly variable pool were more tolerant of higher temperatures when compared to the corals in the moderately variable pool. But the most interesting finding involved the ability of the coral to acclimate to higher water temperatures. Dr Daniel Barshis, part of the team that completed the research, said: "The most important finding was that corals are capable of increasing their thermal tolerance limits substantially in just 12 to 18 months. This acclimation in upper tolerance limits correlates with changes in gene expression as well."
Barshis went on to say that this new knowledge should be integrated into models that predict the effects of global warming on coral reefs to help us understand how they will respond to rising sea temperatures in the future, he said: "This research provides some glimmer of hope that corals may have the ability to survive more than we've given them credit for, but only if we reduce the amount of current and future stresses."
This research also has many real-world applications that could help protect coral reefs from future climate change. Palumbi said, "It should be possible to use climate-resistant corals in transplant/restoration efforts in order to replant reefs with greater future resilience. This is one of the things we are doing this summer in a set of pilot projects in Samoa."
More information: Mechanisms of reef coral resistance to future climate change, Science 23 May 2014: Vol. 344 no. 6186 pp. 895-898. DOI: 10.1126/science.1251336
Reef corals are highly sensitive to heat, yet populations resistant to climate change have recently been identified. To determine the mechanisms of temperature tolerance, we reciprocally transplanted corals between reef sites experiencing distinct temperature regimes and tested subsequent physiological and gene expression profiles. Local acclimatization and fixed effects, such as adaptation, contributed about equally to heat tolerance and are reflected in patterns of gene expression. In less than 2 years, acclimatization achieves the same heat tolerance that we would expect from strong natural selection over many generations for these long-lived organisms. Our results show both short-term acclimatory and longer-term adaptive acquisition of climate resistance. Adding these adaptive abilities to ecosystem models is likely to slow predictions of demise for coral reef ecosystems.
Saturday, March 8, 2014
Hoagy is squawking again
Disaster looming, says the director of the Global Change Institute at the University of Queensland, writing for EarthHour.org. But to quote Mandy Rice-Davies, "But he WOULD say that, wouldn't he?"
I have had a look at Hoagy's "report" and the evidence he musters for bad things happening is mostly quotations from his own writings and the the writings of his fellow Warmists. Andrew Bolt points out that other reef scientists say the reef is doing fine and bounces back swiftly from setbacks.
Hoagy's own research showed a resilient reef a few years ago and Hoagy retreated into embarrassed silence for a while but the embarrassment seems to have faded. Maybe he needed to do a screech to hang on to his job.
But a point that nobody can deny is that the reef is most luxuriant in the WARMEST part of its range e.g. the Torres Strait. The reef LIKES warmth
The Great Barrier Reef will suffer “irreversible” damage by 2030 unless radical action is taken to lower carbon emissions, a stark new report has warned.
Unless temperatures are kept below the internationally agreed limit of 2C warming on pre-industrial levels, the reef will cease to be a coral-dominated ecosystem, the report warns.
Coral bleaching, which occurs when water becomes too warm and coral’s energy source is decimated, is now a “serious threat” to the reef, having not been documented in the region prior to 1979.
The increase in carbon dioxide pumped into the atmosphere, 90% of which is absorbed by the oceans, has already caused a 30% rise in the hydrogen ions that cause ocean acidification. This process hinders the ability of corals to produce the skeletal building blocks of reefs.
Co-author Ove Hoegh-Guldberg, director of the Global Change Institute at the University of Queensland, told Guardian Australia that current climate trends signal “game over” for the Great Barrier Reef.
Tuesday, March 4, 2014
Australia: Let’s dump Great Barrier Reef dredging myths
Mr Reichelt mentions it obliquely but it deserves pointing out WHY good landfill material is being dumped at sea. It is because Greenies won't let it be dumped on land! Dredged material used to be poured directly onto waterfront swamps and mangroves as land reclamation. Most of the Cairns foreshore was built up that way. I watched the dredge TSS Trinity Bay discharging into polders there when I was a boy. But littoral swamps and mangroves are now "wetlands" so must not be touched, even though there are untold miles of them left
AUTHOR: Russell Reichelt, Chairman and Chief Executive of the Great Barrier Reef Marine Park Authority
The Great Barrier Reef Marine Park Authority’s recent decision to allow 3 million cubic metres of dredge material to be disposed of 25 kilometres off Abbot Point in north Queensland has attracted passionate commentary around the world.
Millions of people from Australia and overseas have a fierce desire to protect one of the world’s most beautiful natural wonders. As the independent body managing the Great Barrier Reef for future generations, all of us at the Authority understand and share that desire: it’s what makes us want to come to work every day.
But the debate about Abbot Point has been marked by considerable misinformation, including claims about “toxic sludge”, dumping coal on the reef and even mining the reef. Late last week, it was confirmed that our decision to allow the dredge disposal will be challenged in court.
So what’s true, and what’s not? I hope with this article, I can clear up some of those misunderstandings on behalf of the Authority, particularly about our role, the nature and scale of the dredge disposal activity, and its likely environmental impacts.
If you still have questions at the end of this article, I and others from our team at the Authority will be reading your comments below and we’ll do our best to reply to further questions on The Conversation.
A sizeable challenge
At 344,400 square kilometres, the Marine Park is roughly the same area as Japan or Italy.
Of this vast and richly diverse expanse, one-third is highly protected; some places are near pristine, while others are feeling the effects of centuries of human uses.
But rather than locking the entire area away, the Great Barrier Reef Marine Park Authority’s (GBRMPA) role — as set out under Australian law — is to protect the region’s ecosystem, while also ensuring it remains a multiple-use marine park open to sustainable use. This includes tourism, commercial fishing, shipping and other operations.
While there are five major ports in the region, to this day only 1% of the World Heritage Area is set aside for ports. Most of the region’s 12 ports existed long before the Marine Park was created in 1975, and nearly all fall inside the World Heritage Area, but outside the park itself.
Responding to “toxic” claims
Among the many claims made about the Abbot Point decision is the assertion that the “Reef will be dredged” and that “toxic sludge” will be dumped in marine waters.
Both of those claims are simply wrong, as are suggestions that coal waste will be unloaded into the Reef, that this natural wonder is about to be mined, or that Abbot Point is a new coal port.
The reality is that disposal of dredge material of this type in the Marine Park is not new. It has occurred off nearly all major regional centres along the reef’s coastline before now.
It is a highly regulated activity and does not allow material to be placed on coral, seagrass or sensitive marine environments.
The material itself in Abbot Bay is about 60% sand and 40% silt and clay, which is similar to what you would see if you dug up the site where the material is to be relocated.
In addition, testing by accredited laboratories shows the material is not toxic, and is therefore suitable for ocean disposal.
Limiting new port development
As Queensland’s population has grown over the past 150 years, so too have the size and number of ports along the Great Barrier Reef coastline.
We recognise the potential environmental risks posed at a local level by this growth, which is why we have strongly advocated limiting port development to existing major ports — such as Abbot Point — as opposed to developing new sites.
This will produce a far better outcome than a proliferation of many, albeit smaller, ports along the coastline. And that’s not just our view: it’s a view shared by the UNESCO World Heritage Committee, which oversees the Great Barrier Reef’s listing as one of Australia’s 19 World Heritage sites.
Given Abbot Point has been a major port for the past 30 years, our approval of the dredge disposal permit application from North Queensland Bulk Ports is entirely consistent with this position.
The added benefit of the port is its access to naturally deep waters, meaning it requires less capital dredging than other ports. It also has a much lower need for maintenance dredging.
What’s being done to protect the reef?
With this as our backdrop, we analysed the potential impacts and risks to the Great Barrier Reef from disposing dredge spoil off Abbot Point within the Marine Park.
In this case, we reached the conclusion that with 47 stringent conditions in place, it could be done in a way that makes us confident there will be no significant impact on the reef’s world heritage values.
These safeguards are designed specifically to ensure potential impacts are avoided, mitigated or offset, and to prevent harm to the environmental, cultural or heritage values associated with the nearby Holbourne Island fringing reef, Nares Rock, and the Catalina World War II wreck.
Our conditions are in addition to those already imposed by the federal government in prior approvals.
Again, just to clear up any confusion: the dredge material will not be “dumped on the reef”.
Instead, we are looking at an area within the Marine Park that is about 25 kilometres east-northeast of the port at Abbot Point, and about 40 kilometres from the nearest offshore reef.
When the dredge disposal occurs, the material will only be allowed to be placed in a defined 4 square kilometre site free of hard corals, seagrass beds and other sensitive habitats.
If oceanographic conditions such as tides, winds, waves and currents are likely to produce adverse impacts, the disposal will not be allowed to proceed.
As an added precaution, the activity can only happen between March and June, as this falls outside the coral spawning and seagrass growth periods. As the sand, silt and clay itself will be dredged in stages over three years, the annual disposal volume will be capped at 1.3 million cubic metres.
Compared with other sites in this region, it is much less than has been done in the past. For example, in 2006 there were 8.6 million cubic metres of similar sediments excavated and relocated in one year at Hay Point, near Mackay. Scientific monitoring showed no significant effects on the ecosystem.
The dredge disposal from Abbot Point will be a highly managed activity — and it will not, as some headlines have suggested, mean the Great Barrier Reef will become a sludge repository or that tonnes of mud will be dumped on coral reefs.
This is not Gladstone Harbour all over again
I have often heard during this debate that Abbot Point will become “another Gladstone”.
I can assure you that GBRMPA understands strongly the need to learn the lessons from past port developments, including ones like Gladstone that fall outside of the Marine Park. This is why the recommendations from an independent review into Gladstone Harbour have been factored into our conditions.
Much of the criticism of the development at Gladstone Harbour centred on monitoring and who was doing it. This is why one the most common questions we’ve heard at GBRMPA about Abbot Point is “Who is going to make sure this is all done properly?”
The answer is: there will be multiple layers of independent oversight. Indeed, past authors on The Conversation have used Townsville’s port as a good example of how local impacts can be managed safely through transparent, independent monitoring and reporting, and active on-site management.
This is why we will have a full-time staff member from GBRMPA located at the port to oversee and enforce compliance during dredge disposal operations. This supervisor has the power to stop, suspend or modify works to ensure conditions are met.
In addition, an independent technical advice panel and an independent management response group will be formed. Membership of both these bodies will need the approval of GBRMPA.
Importantly, the management response group will include expert scientists as well as representatives from the tourism and fishing industries, and conservation groups. Together, GBRMPA and those other independent scrutineers will be overseeing the disposal, and will have the final say — not North Queensland Bulk Ports, which operates Abbot Point, or the coal companies that use the port.
Water quality monitoring will take place in real-time to measure factors such as suspended solids, turbidity and light availability. This is in addition to a long-term water quality monitoring program that will run for five years — much longer than what is normally required.
It’s vital that there is utmost transparency and scrutiny of what happens. We believe that with our staff on the job, plus independent oversight that includes the community, it will be a highly transparent process.
What are limits of the Authority’s powers?
It is true to say that despite all these safeguards, placing dredge material on land rather than in the Marine Park remains our preferred choice, providing it does not mean transferring environmental impact to sensitive wetlands connected to the reef ecosystem.
Indeed, land-based disposal is an option that must always be examined under national dredging guidelines.
But we recognise onshore disposal is not always immediately practical. Some of the challenges include finding suitable land, the need for dredge settlement ponds and delivery pipelines, and potential impacts on surrounding environments.
Ultimately, what occurs on land is outside of GBRMPA’s jurisdiction. We do not make decisions about mines, railways and loading facilities, and have never had the power to compel a port authority to place dredged material onshore or to build an extension to existing jetties.
Nor do we have the ability to stop dredge disposal from occurring in port limits that fall inside the World Heritage Area, but outside of the Marine Park.
Our legislative powers simply enable us to approve or reject a permit application for an action in the Marine Park, or to approve it with conditions.
Based on the considerable scientific evidence before us, we approved the application for Abbot Point with conditions, on the basis that potential impacts from offshore disposal were manageable and that there would be no significant or lasting impacts on the reef’s world heritage values.
Monday, February 10, 2014
Can Migrating Corals Outpace Ocean Warming and Acidification?
Discussing: Couce, E., Ridgwell, A. and Hendy, E.J. 2013. "Future habitat suitability for coral reef ecosystems under global warming and ocean acidification". Global Change Biology 19: 3592-3606.
According to Couce et al. (2013), "there is concern that the growing frequency and severity of mass bleaching episodes may lead to species composition shifts and functional collapse in coral reefs in the near future." On the other hand, they also note global warming "has the potential to improve currently marginal environmental conditions and extend the range of tropical coral reefs into higher latitudes," as is "demonstrated in the fossil record in response to warmer geological periods (e.g., Lighty et al., 1978; Veron, 1992; Precht and Aronson, 2004; Greenstein and Pandolfi, 2008; Woodroffe et al., 2010; Kiessling et al., 2012)."
But what if ocean acidification occurs concurrently?
To investigate this potential situation, Couce et al. employed "a suite of statistical models based on the environmental factors thought to be limiting to the present equilibrium distribution of shallow-water coral reefs, perturbing them with Earth System Model projected future sea surface temperatures and aragonite saturation changes (the simulations used in Turley et al., 2010)," while considering "a range of potential future CO2 emissions scenarios," but focusing on "the consequences of the 'A2' scenario (characterized by regionally oriented economic development and high population growth, expecting ca. 850 ppm CO2 by 2100)."
After all was said and done, the three UK researchers found, "contrary to expectations, the combined impact of ocean surface temperature rise and acidification leads to little, if any, degradation in future habitat suitability across much of the Atlantic and areas currently considered 'marginal' for tropical corals, such as the eastern Equatorial Pacific." And they note, in this regard, that "these results are consistent with fossil evidence of range expansions during past warm periods."
In terms of the nitty-gritty here-and-now, Couce et al. conclude by stating that their results "present important implications for future coral reef management, as they suggest that more emphasis should be placed on conservation efforts on marginal reefs as they are not necessarily a 'lost cause'."
Monday, February 3, 2014
Coral reefs in Palau surprisingly resistant to naturally acidified waters
Ocean researchers working on the coral reefs of Palau in 2011 and 2012 made two unexpected discoveries that could provide insight into corals' resistance and resilience to ocean acidification, and aid in the creation of a plan to protect them.
The team collected water samples at nine points along a transect that stretched from the open ocean, across the barrier reef, into the lagoon and then into the bays and inlets around the Rock Islands of Palau, in the western Pacific Ocean. With each location they found that the seawater became increasingly acidic as they moved toward land.
"When we first plotted up those data, we were shocked," said lead author Kathryn Shamberger, then a postdoctoral scholar at Woods Hole Oceanographic Institution (WHOI) and a chemical oceanographer. "We had no idea the level of acidification we would find. We're looking at reefs today that have levels that we expect for the open ocean in that region by the end of the century."
Shamberger conducted the fieldwork in Palau with other researchers from the laboratory of WHOI biogeochemist Anne Cohen as well as scientists from the Palau International Coral Reef Center (PICRC).
While ocean chemistry varies naturally at different locations, it is changing around the world due to increased levels of carbon dioxide (CO2) in the atmosphere. The ocean absorbs atmospheric CO2, which reacts with seawater, lowering its overall pH, and making it more acidic. This process also removes carbonate ions needed by corals and other organisms to build their skeletons and shells. Corals growing in low pH conditions, both in laboratory experiments that simulate future conditions and in other naturally low pH ocean environments, show a range of negative impacts. Impacts can include juveniles having difficulty constructing their skeletons, fewer varieties of corals, less coral cover, more algae growth, and more porous corals with greater signs of erosion from other organisms.
The new research, published in Geophysical Research Letters, a journal of the American Geophysical Union, explains the natural biological and geomorphological causes of the more acidic water near Palau's Rock Islands and describes a surprising second finding – that the corals living in that more acidic water were unexpectedly diverse and healthy. The unusual finding, which is contrary to what has been observed in other naturally low pH coral reef systems, has important implications for the conservation of corals in all parts of the world.
"When you move from a high pH reef to a low pH neighboring reef, there are big changes, and they are negative changes," said Cohen, a co-author on the paper and lead principal investigaor of the project. "However, in Palau where the water is most acidic, we see the opposite. We see a coral community that is more diverse, hosts more species, and has greater coral cover than in the non-acidic sites. Palau is the exception to the places scientists have studied."
Through analysis of the water chemistry in Palau, the scientists found the acidification is primarily caused by the shell building done by the organisms living in the water, called calcification, which removes carbonate ions from seawater. A second reason is the organisms' respiration, which adds CO2 to the water when they breathe.
"These things are all happening at every reef," said Cohen. "What's really critical here is the residence time of the sea water."
"In the Rock Islands, the water sits in the bays for a long time before being flushed out. This is a big area that's like a maze with lots of channels and inlets for the water to wind around," explained Shamberger. "Calcification and respiration are continually happening at these sites while the water sits there, and it allows the water to become more and more acidic. It's a little bit like being stuck in a room with a limited amount of oxygen – the longer you're in there without opening a window, you're using up oxygen and increasing CO2."
Ordinarily, she added pushing the analogy, without fresh air coming in, it gets harder and harder for living things to thrive, "yet in the case of the corals in Palau, we're finding the opposite. "What we found is that coral cover and coral diversity actually increase as you move from the outer reefs and into the Rock Islands, which is exactly the opposite of what we were expecting."
The scientists' next steps are to determine if these corals are genetically adapted to low pH or whether Palau provides a "perfect storm" of environmental conditions that allows these corals to survive the low pH. "If it's the latter, it means if you took those corals out of that specific environment and put them in another low pH environment that doesn't have the same combination of conditions, they wouldn't be able to survive," said Cohen. "But if they're genetically adapted to low pH, you could put them anywhere and they could survive."
"These reef communities have developed under these conditions for thousands of years," said Shamberger, "and we're talking about conditions that are going to be occurring in a lot of the rest of the ocean by the end of the century. We don't know if other coral reefs will be able to adapt to ocean acidification – the time scale might be too short."
The scientists are careful to stress that their finding in Palau is different from every other low pH environment that has been studied. "When we find a reef like Palau where the coral communities are thriving under low pH, that's an exception," said Cohen. "It doesn't mean coral reefs around the globe are going to be OK under ocean acidification conditions. It does mean that there are some coral communities out there – and we've found one – that appear to have figured it out. But that doesn't mean all coral reef ecosystems are going to figure it out."
"In Palau, we have these special and unique places where organisms have figured out how to survive in an acidified environment. Yet, these places are much more prone to local human impacts because of their closeness to land and because of low circulation in these areas," said co-author Yimnang Golbuu, CEO of the PICRC. "We need to put special efforts into protecting these places and to ensure that we can incorporate them into the Protected Areas Network in Palau."
Australia has argued it is making substantial progress on the United Nations' requests for better protection of the Great Barrier Reef and that it should not be listed among world heritage sites "in danger".
In a progress report to the UN World Heritage Committee, the federal and Queensland governments say the natural values the reef was protected for are still largely intact, although in parts - such as inshore areas south of Cooktown - they are declining.
The report was delivered to the UN on Saturday, a day after final approval was granted to dump in the reef's waters 3 million cubic metres of dredging sludge from the expansion of coal export terminals at Abbot Point.
The World Heritage Committee has threatened to put the reef on a list of world heritage sites considered "in danger" after becoming concerned in 2012 about the effect of numerous resource projects slated for the reef's coast.
Australia needs to show significant progress on UN recommendations for better reef management to avoid a downgrade. Tourism operators warn an "in danger" listing will damage the reef's international reputation and their businesses.
The governments' report points to several programs to reduce threats, including a sustainability strategy, water quality measures and a draft Queensland ports strategy.
Federal Environment Minister Greg Hunt said there was genuine improvement in reef indicators in regard to dugongs, turtles, seagrass and coral. The Coalition had rejected Labor's multiple new-port strategy and was containing development to five existing port areas, he said.
"It is a permanent task for every Australian government to protect and maintain the reef. Nobody can ever rest on that, but there should be no way the reef can and should be considered 'in danger'," Mr Hunt said.
Australian Coral Reef Society president Peter Mumby said many people had argued convincingly that the reef was in the worst shape since monitoring began. He said the progress report downplayed industrial development threats, including port and agriculture expansion, that could add as much as another 14 million tonnes a year of damaging sediment to reef waters.
University of Queensland coral reef ecologist Selina Ward said the Abbot Point decision was dangerous because the best modelling showed dumped sediment would drift to outer areas, damaging coral and seagrass.
The government progress report said extreme weather and climate change were the biggest threats to the reef. It also pointed to nutrient and sediment run-off from land clearing and agriculture, and associated spikes in crown-of-thorns starfish numbers.
It said pollution from other sources, including port development and dredging, "is minor but may be highly significant locally and over short time periods".
Queensland Resources Council chief executive Michael Roche said the governments' progress report had identified the port development impacts as being minor and temporary.
Monday, January 27, 2014
Coralline algae in a high CO2 world: How do they cope?
Discussing: Ragazzola, F., Foster, L.C., Form, A.U., Buscher, J., Hansteen, T.H. and Fietzke, J. 2013. "Phenotypic plasticity of a coralline algae in a high CO2 world". Ecology and Evolution 3: 3436-3446.
Ragazzola et al. (2013) introduce their study by noting that coralline algae have been shown to be a major contributor to the formation and stabilization of coral reefs and in enhancing coral larvae settlement, citing Chisholm (2000). And due to what they call "their crucial role in shallow water ecosystems and their worldwide distribution," they say that "understanding the impact of ocean acidification on calcifying algae is fundamental," especially since "their high-Mg calcite skeleton is the most soluble polymorph of CaCO3 (50% more soluble than calcite and 20% more soluble than aragonite)," and that coralline algae are therefore "likely to be particularly sensitive to a reduction in Ω," which is the calcium carbonate saturation state of seawater, citing Ries (2011), Burdett et al. (2012) and Martin et al. (2013).
Due to the fact that "species with wide geographic ranges, such as coralline algae, are in general very plastic and able to acclimatize to a variety of habitats through morphological and functional responses (Brody, 2004)," Ragazzola et al. cultured Lithothamnion glaciale, one of the main maerl-forming species in the northern latitudes, under different elevated CO2 levels (410, 560, 840, 1120 ppm = 8.02, 7.92, 7.80, 7.72 pH ) for a period of ten months, but with initial analyses of the various parameters they measured being conducted at the three-month point of the study, as reported by Ragazzola et al. (2012).
In doing so, the six scientists report that the growth rates of the plants in the three CO2-enriched treatments after the first three months of their study were not significantly different from either each other or from those of the ambient-treatment plants.
At the end of the ten-month experiment, however, the CO2-enriched plants' growth rates were approximately 60% lower than that of the ambient-treatment plants. On the other hand, they found that the individual cell wall thicknesses of both inter and intra filaments at the three-month point of the study were significantly thinner than those of the control plants, whereas at the end of the ten-month study they were equivalent to those of the control plants.
In discussing these findings, Ragazzola et al. (2013) write that a possible explanation for them is "a shift from what could be termed a 'passive' phase during the first three months to an 'active' phase by the end of ten months," whereby "during the 'passive' phase, the increased energy requirement for calcification due to higher CO2 results in a reduction in the amount of calcite deposited in each cell well," but during the 'active phase,' L. glaciale reduces its growth rate so that the cell wall structure can be better maintained.
Noting that maintaining skeletal integrity is one of the main priorities of marine organisms living in high CO2 environments, the German and UK researchers say "the results of this study indicate that seawater chemistry can drive phenotypic plasticity in coralline algae," and that "the ability to change the energy allocation between cell growth and structural support is a clear adaptive response of the organism," which they say "is likely to increase its ability to survive in a high CO2 world."
Friday, December 13, 2013
Great Barrier Reef Marine Park Authority scientists say baby corals are blooming on the Great Barrier Reef
GBRMPA and Queensland Parks and Wildlife Service have carried out their second inspection of a series of reefs between Townsville and Tully, in the wake of cyclone Yasi.
GBRMPA's Climate Change and Ecosystems Manager Roger Beeden has been heading up the survey and says that the coral bloomings are a positive sign of recovery.
"We are seeing baby corals in some of the shallows and also in some of the deeper areas," he said.
"It is showing that even though it has had multiple impacts in the last few years, it is able to bounce back.
"It has got that natural resilience to recover, provided it doesn't get hit with too many other events."
Mr Beeden says many parts of the reef looked like "moonscapes" when they surveyed after cyclone Yasi.
"Even though coral are animals it was akin to seeing a whole forest knocked down in lots of places," he said.
"That was really, almost heart breaking for many of us to see, and yet two years on we are beginning to see lots of the early signs of recovery."
Mr Beeden says it is not just wind from the cyclones that causes damage to the coral.
"During cyclone Yasi ... there were some monitoring stations that are out on reefs and there was actually mixing in the water down to 200 metres in some places," he said.
"So it was a huge event in terms of moving water around and it is that water movement that caused the damage to about 15 per cent of the Great Barrier Reef."
Mr Beeden says it is good news for fast growing coral, but there are slower growing coral that need more time.
"In the fast growing ones we can begin to see quite good recovery in 5-10 years, but in the really big ones, the kind of huge, great big trees if you like, actually can take decades to centuries to recover," he said.
"What we are seeing now is actually the ones that are 2 or 3 years old, so they are actually the ones that have spawned after cyclone yasi and you can actually visibly see them now on the reef."