Balance of nature: importance of ocean ecosystems (Introduction)

by David Turell , Tuesday, August 09, 2022, 19:20 (625 days ago) @ David Turell

Phytoplankton's at the base if life's ecosystems:

https://phys.org/news/2022-08-daynight-global-ocean.html

"Phytoplankton is the foundation of all life on the planet. Understanding how these photosynthetic organisms react to their ocean environment is important to understanding the rest of the food web.

"In spite of that, computer models of the global ocean biogeochemistry typically don't include the day/night (diel) light cycle, even though that cycle is critical for photosynthesis in the ocean's primary producers.

"For the first time, scientists from the Ecosystems Center at the Marine Biological Laboratory (MBL) have incorporated the diel cycle into a global ocean model in order to investigate its effects on phytoplankton.

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"The researchers found that the diel cycle did indeed matter to the simulated phytoplankton.

"'We know that a lot of traits of different phytoplankton are based on the day/night cycle. Some dinoflagelletes go deeper [in the water column] to get more nutrients and then go up to photosynthesize. Some store carbon during the day, so they can use it at night," says Ioannis Tsakalakis, MBL postdoctoral researcher and first author on the paper.

"The model showed that diel cycles are associated with higher concentrations of limited nutrients, which meant that at lower latitudes (−40° to 40°), the simulated opportunists were more abundant than the gleaners compared to the control simulation. This includes phytoplankton like diatoms. This mechanism became less important at higher latitudes, where the effects of the seasonal light cycle were stronger than the day/night cycles.

"If scientists don't understand how phytoplankton are getting their energy as primary producers at the base of the food web, it's hard to make inferences about the interactions of the rest of that global ocean food web—all the way up to humans.

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"'This model contributes to advancing our fundamental understanding of how the ocean works," says Vallino, adding that as scientists make better ocean models, eventually they may use them to investigate possible solutions to climate change while minimizing unintended consequences.

"'Being able to predict how the distribution of phytoplankton will change is going to have repercussions higher up the food web," says Vallino. "If you can't get that base change right, you can't get anything that's connected to that above it.'"

Comment: this shows how some of the earliest evolved forms contribute to today's food supply. And it supports my claim that all of evolution was necessary to produce humans.