In a first, researchers from the University of California, Irvine - as well as Switzerland's University of Zurich, IBM Research-Zurich and UC Santa Cruz - have obtained direct images of dissolved organic carbon molecules from the ocean, allowing better analysis and characterization of compounds that play an important role in the Earth's changing climate.

Using an atomic force microscopy technique developed by IBM, the team was able to visualize individual atoms and bonds, yielding clues about their persistence in the marine environment. Findings were published in the American Geophysical Union journal Geophysical Research Letters.

"To understand processes happening on the scale of ocean basins, it is sometimes necessary to view objects that are orders of magnitude smaller," said study co-author Ellen Druffel, professor and Fred Kavli Chair of Earth System Science at UCI. "By seeing with our own eyes the double bonds and rings of dissolved organic carbon molecules, we are better equipped to explain how they remain in the ocean for tens of thousands of years."

The molecules that were imaged were collected by UC Santa Cruz researchers from waters in the northern central Pacific Ocean.

The marine dissolved organic carbon pool, comparable in size to the atmospheric CO2 reservoir, is about 200 times larger than the amount of carbon contained in all the plants and animals on the planet. Because of its complexity, diverse origins and varied reactions to environmental conditions, only about 10 percent of DOC has been characterized.

"We are still trying to figure out how the vast majority of this substance is going to be impacted by the ongoing addition of new CO2 from fossil fuel burning and from increasing temperatures due to global climate change," said co-author Brett Walker, a UCI assistant researcher in Earth system science.

Most DOC near the ocean surface is derived from the remains of recently living phytoplankton. However, radiocarbon dating of DOC in the deep ocean shows it to be much older than expected - by as much as 4,500 years - indicating that a portion of this DOC survives multiple ocean mixing cycles.

Researchers have suggested that the chemical structure of DOC is responsible for its endurance in the environment, and through the atomic force microscopy technique, scientists are now able to see real-space images of the bound atoms in these compounds. The team has found that molecules from the deep ocean frequently exhibit aromaticity, meaning they're flat rings of atoms that are very stable and do not break apart easily.

"These atom-scale visualizations help demonstrate that the old age of small DOC molecules in the deep ocean has to do with their chemical structure, which bacteria do not seem to utilize," Walker said.

"This is a crucial finding that will help researchers better understand the cycling of carbon in the oceans and the overall health of our planet's marine environments."

Related Links
University of California - Irvine
Carbon Worlds - where graphite, diamond, amorphous, fullerenes meet

Tweet

Thanks for being here; We need your help. The Space Media Network continues to grow but revenues have never been harder to maintain. With the rise of Ad Blockers, and Facebook - our traditional revenue sources via quality network advertising continues to decline. And unlike so many other news sites, we don't have a paywall - with those annoying usernames and passwords. Our news coverage takes time and effort to publish 365 days a year. If you find our news sites informative and useful then please consider becoming a regular supporter or for now make a one off contribution.
SpaceMediaNetwork Contributor $5 Billed Once credit card or paypal		SpaceMediaNetwork Monthly Supporter $5 Billed Monthly paypal only

World's most efficient production of succinate from carbon dioxide
Kobe, Japan (SPX) Jun 11, 2018
Succinate is widely used as a raw ingredient for petrochemicals, and there is high demand for a way of producing succinate that is renewable and environmentally benign. A Japanese researcher has discovered that succinate production levels increase when cyanobacteria is grown above the ideal temperature for cell growth. He used insights into the metabolic pathway engineering to achieve the world's most efficient production rate for bio-succinate. The discovery was made by Professor Tomohisa Hasunum ... read more