According to a report in the Independent, phytoplankton of the oceans has declined by more than 40 per cent over the past century and that change is inextricably linked to rising sea temperatures and global warming.
The study, published in the journal Nature, is the first analysis of its kind.
The report, quoting scientists, says if the findings are confirmed by further studies it will represent the single biggest change to the world -- even bigger than the destruction of the tropical rainforests and coral reefs.
According to the reports, phytoplanktons are microscopic marine organisms capable of photosynthesis, just like terrestrial plants. They float in the upper layers of the oceans, provide much of the oxygen we breathe and account for about half of the total organic matter on Earth. A 40 per cent decline, scientists say, represent a massive change to the global biosphere.
"I've been trying to think of a biological change that's bigger than this and I can't think of one," marine biologist Boris Worm of Canada's Dalhousie University in Halifax, Nova Scotia told Independent.
He added, "If real, it means that the marine ecosystem today looks very different to what it was a few decades ago and a lot of this change is happening way out in the open, blue ocean where we cannot see it. I'm concerned about this finding."
They studied phytoplankton records going back to 1899 when the measure of how much of the green chlorophyll pigment of phytoplankton was present in the upper ocean was monitored regularly.
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