- 11.1 billion plastic items are entangled on reefs in oceans: Study
- Researchers surveyed 159 coral reefs in Asia-Pacific region
- When plastic meets coral, the likelihood of disease increases 20 times
New Delhi: Oceans are choking on plastic junk as more than eight million tonnes of plastic waste (water bottles, soda bottles, drinking straws and single use plastic bags) make their way into the oceans every year, the United Nations reports. The floating plastic debris is wreaking havoc on aquatic ecosystem, killing turtles and other underwater creatures. Now, another inhabitant of the oceans may be in danger. The scientists have found that plastic trash massively increased the chance of disease in corals, the tiny animals with living tissue that cling together and build upon one another to form “apartments,” or reefs. The researcher Joleah Lamb at Cornell University in Ithaca, New York, and her colleagues surveyed around 159 reefs in the Asia-Pacific region (contains 55.5 percent of global coral reefs and encompasses 73 percent of the global human population) for signs of disease and plastic pollution, and discovered a dramatic correlation: the likelihood of disease on a coral free of plastic waste was only 4 percent, but jumped to 89 percent on a coral infected by plastic, registering a 20-fold change.
Between 2011 and 2014, the researchers surveyed the reefs in Myanmar, Thailand, Indonesia, and Australia, where they examined the health of more than 124,000 corals and also checked to see whether these y were hosting any pieces of plastic larger than 0.5 centimeters.
We found that the chance of disease increased from four per cent to 89 per cent when corals are in contact with plastic, said Joleah Lamb.
According to the study, the plastic trash can carry bacterial pathogens and hard debris might wound corals, triggering infection. And if plastic debris blocks sunlight, it could lead to low-oxygen conditions that promote the growth of disease-causing bacteria. “What’s troubling about coral disease is that once the coral tissue loss occurs, it’s not coming back. It’s like getting gangrene on your foot and there is nothing you can do to stop it from affecting your whole body,” the researcher said.
In her research, she further highlighted that the problem of plastic waste looks to be getting worse.
We estimate there are 11.1 billion plastic items on coral reefs across the Asia-Pacific and forecast this to increase by 40 percent within seven years, she said.
The study noted that the finding adds to the burden of climate-related disease outbreaks that have already had an impact on coral reefs globally. “Coral Bleaching (when water is too warm, corals will expel the algae living in their tissues causing the coral to turn completely white) events are projected to increase in frequency and severity as ocean temperatures rise. There are more than 275 million people relying upon coral reefs for food, coastal protection, tourism income, and cultural significance,” said Professor Bette Willis, from the James Cook University in Australia.
So moderating disease outbreak risks in the ocean will be vital for improving both human and ecosystem health, said the professor.
The scientists forecast that by 2025, plastic going into the marine environment will increase to roughly 15.7 billion plastic items on coral reefs, which could lead to skeletal eroding band disease, white syndromes and black band disease.
Our work shows that plastic pollution is killing corals. Our goal is to focus less on measuring things dying and more on finding solutions, said senior author Drew Harvell, professor of ecology and evolutionary biology.
While we can’t stop the huge impact of global warming on coral health in the short term, this new work should drive policy toward reducing plastic pollution, the research suggests.
The study also highlights that coral reef, which provides vital fisheries and coastal defense, need urgent protection from the damaging effects of plastic waste, and the reduction in the amount of plastic waste entering the ocean will have direct benefits to coral reefs by reducing disease-associated mortality.
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