Posts Tagged ‘Oceans’

Bioluminescence Flashes to the Rescue

Monday, January 16th, 2012

Very cool article a couple of weeks back in the NY Times about Laura  Widder, a famed marine biologist, who has discovered that the bioluminescence of thousands of microbial sea creatures can be used to measure the toxicity of marine sludge:

Dr. Widder has found a way to put bioluminescence to work to fight pollution in the Indian River Lagoon, a 156-mile estuary that scientists say is one of Florida’s most precious and threatened ecosystems.

Back in her laboratory here, she mixes the sediment samples with a bioluminescent bacterium called Vibrio fischeri. Using a photometer to measure the light given off by the bacteria, she can quickly determine the concentration of toxic chemicals in the sediment by seeing how much and how quickly the light dims as the chemicals kill the bacteria.

Measuring the level of pollutants in the sediment provides a better indication of the estuary’s health than measuring the level of chemicals in the water, Dr. Widder said. “Pollution in water is transient,” she said, “but in sediment it’s persistent.”

Her samples have revealed high concentrations of heavy metals and nutrients like phosphorus and nitrogen, which can cause runaway algae growth; those organisms consume oxygen and stifle life in the estuary. Dr. Widder has also designed sensors that are placed around the estuary and can beam real-time data like current and flow direction of the water. Pairing those data with the toxicity of the sediment, she can trace the source of pollution. The method is far cheaper and quicker than the more common practice of sending samples to a lab for analysis.

She does most of her work at ORCA [Ocean Research and Conservation Organization] where you can find more about her, and the work of ORCA

The Ocean is Breaking – and That’s Not A Good Thing

Tuesday, June 21st, 2011

The changes to the world’s oceans from warming, acidification and the resultant hypoxia are far greater in magnitude  than previously thought, and are happening much faster than predicted.

This is the conclusion of leading researchers on ocean stress, from an April, 2011 workshop at Oxford University.

The key points needed to drive a common sense rethink are:

 

  • Human actions have resulted in warming and acidification of the oceans and are now causing increased hypoxia.
  • The speeds of many negative changes to the ocean are near to or are tracking the worst case scenarios from IPCC and other predictions.  Some are as predicted but many are faster than anticipated, and many are still accelerating.
  • The magnitude of the cumulative impacts on the ocean is greater than previously understood.
  • Timelines for action are shrinking.
  • Resilience of the ocean to climate change impacts is severely compromised by the other stressors from human activity, including fisheries, pollution and habitat destruction.
  • Ecosystem collapse is occurring as a result of both current and emerging stressors.
  • The extinction threat to marine species is rapidly increasing.

The workshop was led by the International Programme on the State of the Ocean (IPSO) together with International Union for the Conservation of Nature (IUCN)

Full report here.

 

More in a Travis Donovan post at HuffPo and by Richard Black at BBC.

 

 

Jellyfish LOVE Global Warming

Saturday, November 28th, 2009

In some yucky news that may catch more attention than mere Pacific Islanders losing their entire homes jelly fish have shown by their activities to appreciate the new footholds provided by warmer waters and fertilizer enriched waters.

Once considered a rarity occurring every 40 years, jellyfish swarms are now an almost annual occurrence along several thousand kilometers of Japanese coast, and far beyond Japan.

Scientists believe climate change – the warming of oceans – has allowed some of the almost 2,000 jellyfish species to expand their ranges, appear earlier in the year and increase overall numbers, much as warming has helped ticks, bark beetles and other pests to spread to new latitudes.

The gelatinous seaborne creatures are blamed for decimating fishing industries in the Bering and Black seas, forcing the shutdown of seaside power and desalination plants in Japan, the Middle East and Africa, and terrorizing beachgoers worldwide, the U.S. National Science Foundation says.

… Increasingly polluted waters – off China, for example – boost growth of the microscopic plankton upon which “jellies” feed, and overfishing has eliminated many of the jellyfish’s predators and cut down on competitors for plankton feed.

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