Skip to main content

Business-as-usual approach to curbing CO2 emission could kill vital corals by 2100 (downtoearth)

In a further vindication of claims that ocean acidification is wiping our coral reefs from marine ecosystem, a Griffith University study on the Great Barrier Reef has revealed that CO2 emissions help coral-killing seaweeds grow more poisonous and thus, accelerate destruction of coral reefs worldwide.

The study was conducted on Heron Island by reef and chemical ecology experts from the University of Queensland and the US. According to the study, “business as usual” emissions would harm vital corals by 2050 and kill them by 2100.

The findings shed new light on the competitive advantage that seaweeds have over corals in seawater with increasing concentrations of CO2. Moreover, the scale of the problem is so big, that removing a bunch of seaweed from the reef doesn’t help much as it just regrows and regenerates. So, the solution doesn’t lie in cutting off seaweeds but in reducing carbon emissions.

Calling this study “a major step forward in understanding how seaweeds can harm corals”, Guillermo Diaz-Pulido, associate professor at Griffith University, said that the research has “important implications for comprehending the consequences of increased carbon dioxide emissions on the health of the Great Barrier Reef”.

While it was known that increased carbon dioxide in the atmosphere affects the behaviour of seaweed as oceans absorb CO2 and turn more acidic, this study discovers that greater carbon concentrations led to “some algae producing more potent chemicals that suppress or kill corals more rapidly”, in some cases in just weeks.

According to the study’s co-author, Mark Hay, a professor from the Georgia Institute of Technology, “If the algae overtake the coral, we have a problem which contributes to reef degradation, on top of what we already know with coral bleaching, crown of thorn starfish outbreaks, cyclones or any other disturbance.”

Methodology

With  an objective of understanding to what extent would the CO2 affect some of the things algae do, the researchers focussed their attention on  the Heron Island, located north-east of Gladstone at the southern end of the Great Barrier Reef. They used both underwater reef experiments and outdoor lab studies to arrive at a conclusion.

Conclusion

A common brown algae species, which is found in reefs worldwide, has been identified as one of those weeds that caused the maximum damage. Algae, like any other plant, need light and CO2 to grow. When this algae takes advantage of elevated CO2 in seawater, it becomes a matter of concern. The research document states, “Elevated seawater CO2 concentrations may enhance fleshy algal growth rates, reduce coral growth and calcification rates, and strengthen space competition between macroalgae and corals, with outcomes that favour macroalgae over corals.” Researchers concluded that the way to tackle this threat is to reduce the levels of CO2 in the atmosphere.

Comments

Popular posts from this blog

Cloud seeding

Demonstrating the function of the flare rack that carries silver iodide for cloud-seeding through an aircraft. 
Water is essential for life on the earth. Precipitation from the skies is the only source for it. India and the rest of Asia are dependent on the monsoons for rains. While the South West Monsoon is the main source for India as a whole, Tamil Nadu and coastal areas of South Andhra Pradesh get the benefit of the North East Monsoon, which is just a less dependable beat on the reversal of the South West Monsoon winds.

SC asks Centre to strike a balance on Rohingya issue (.hindu)

Supreme Court orally indicates that the government should not deport Rohingya “now” as the Centre prevails over it to not record any such views in its formal order, citing “international ramifications”.

The Supreme Court on Friday came close to ordering the government not to deport the Rohingya.

It finally settled on merely observing that a balance should be struck between humanitarian concern for the community and the country's national security and economic interests.

The court was hearing a bunch of petitions, one filed by persons within the Rohingya community, against a proposed move to deport over 40,000 Rohingya refugees. A three-judge Bench, led by Chief Justice of India Dipak Misra, began by orally indicating that the government should not deport Rohingya “now”, but the government prevailed on the court to not pass any formal order, citing “international ramifications”. With this, the status quo continues even though the court gave the community liberty to approach it in …

India’s criminal wastage: over 10 million works under MGNREGA incomplete or abandoned (hindu)

In the last three and half years, the rate of work completion under the Mahatma Gandhi National Rural Employment Guarantee Act (MGNREGA) has drastically declined, leading to wastage of public money and leaving villages more prone to drought. This could also be a reason for people moving out of the programme.

At a time when more than one-third of India’s districts are reeling under a drought-like situation due to deficit rainfall, here comes another bad news. The works started under the MGNREGA—close to 80 per cent related to water conservation, irrigation and land development—are increasingly not being completed or in practice, abandoned.

Going by the data (as on October 12) in the Ministry of Rural Development’s website, which tracks progress of MGNREGA through a comprehensive MIS, 10.4 million works have not been completed since April 2014. In the last three and half years, 39.7 million works were started under the programme. Going by the stipulation under the programme, close to 7…