Evolution: marine snow econiche (Introduction)

by David Turell , Monday, December 03, 2018, 19:03 (1971 days ago) @ David Turell

T he econiche in the ocean involves death and decomposing bodies reaching the bottom of oceans to supply food for bottom dwellers:

https://phys.org/news/2018-12-pulses-carbon-deep-sea-captured.html

"More than two miles below the ocean's surface, microbes, worms, fishes, and other creatures great and small thrive. They rely on the transport of dead and decaying matter from the surface (marine snow) for food at these dark depths.

"Up near the sea surface, carbon dioxide from the atmosphere is incorporated in the bodies of microscopic algae and the animals that eat them. When they die, these organisms sink to the depths, carrying carbon with them.

"This supply of carbon to the deep sea isn't steady. At times, months' to years' worth of marine snow falls to the abyss during very short "pulse" events.

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"The PNAS study focused on six periods between 2011 and 2017 when large amounts of marine snow reached sediment traps at Station M. During these episodic pulse events, four times more carbon reached the deep sea each day, in comparison to non-pulse days.

"Compared to the first 20 years of the time-series, pulse events became more prevalent after 2011. Of the total carbon that reached the sediment traps at 3,400 meters depth from 2011 to 2017, over 40 percent arrived during the pulse events.

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"These events are becoming a much bigger part of the carbon cycle," said Christine Huffard, a marine biologist at MBARI and co-author of the study. In fact, since these pulse events have become larger and more frequent, researchers have had to double the size of the collection cups used in their sediment traps.

"The pulses of food (and carbon) to the deep sea are not currently taken into account in global climate models. The "Martin curve" formula, which is based on sea-surface conditions such as water temperature, is widely used to estimate how much carbon reaches the deep sea.

"Huffard and her coauthors found that the Martin curve matched their data well on non-pulse days, but it underestimated the amount of carbon arriving during pulse events by 80 percent.

"'In total the Martin curve estimated only half the deep-sea carbon that we measured," said Huffard."

Comment: Surprise! Mammals in the ocean add to the bottom food supply as they die and decompose. Another example of how delicate econiches are set up to provide food supply. The niches are part of God's design for life to survive and evolve over long stretches of time. I'm sorry dhw can't see the logic.