Nav: Home

New insight into glaciers regulating global silicon cycling

August 14, 2019

A new review of silicon cycling in glacial environments, led by scientists from the University of Bristol, highlights the potential importance of glaciers in exporting silicon to downstream ecosystems.

This, say the researchers, could have implications for marine primary productivity and impact the carbon cycle on the timescales of ice ages.

This is because silica is needed by primary producers, such as diatoms (a form of algae that account for up to 35 percent of all marine primary productivity), and these primary producers remove significant amounts of carbon dioxide from the atmosphere, transporting it to the deep ocean.

Lead author Jade Hatton from the University of Bristol's School of Earth Sciences, said: "It is important we understand the role glaciers play in silicon cycling and we have examined previously published work considering subglacial weathering and nutrient fluxes to bring together this review, focusing upon the chemical fingerprint of silicon exported from these environments."

The team, whose findings were published this week in the journal Proceedings of Royal Society A, considered some of the 'big questions' currently surrounding glaciers and silicon export including the differences in the chemical fingerprint of silicon between glacial and non-glacial rivers, and if weathering processes occurring beneath glaciers are driving these differences.

Through combining new measurements of meltwaters from over 20 glaciers in Iceland, Alaska, Greenland and Norway with existing data, the paper shows that the chemical fingerprint of silicon exported from glaciers is distinct compared to silicon within non-glacial rivers.

This chemical signature (the silicon isotopic composition) helps to understand the nature of weathering processes occurring beneath glaciers.

Jade Hatton added: "Data from such a range of glaciers represents a significant endeavour in terms of fieldwork and represent a vast improvement in our knowledge of the isotopic signature of silicon from glaciers.

"We suggest that the distinct silicon isotopic composition in glacial waters is driven by the high physical erosion rates beneath glaciers.

"This has implications on how we understand subglacial weathering processes and the export of nutrients from glacial environments."

These new data are presented alongside work previously carried out in Iceland and Greenland to provide stronger evidence that the relationship between glacial meltwaters and a distinct silicon isotope signature holds.

The researchers hope this wider data set will help inform more complex computer models in the future, building on our previous modelling work that has demonstrated the importance of glacial silica on glacial-interglacial timescales.

The paper also provides a discussion of the complexities of glacial environments and highlights some of the important questions that are still uncertain, including the importance of particulate silica when considering the overall export flux from glacial environments.

Jade Hatton said: "Very little work has been done to understand the formation of this 'amorphous' silica beneath glaciers. We suggest the high physical erosion within these systems is extremely important, however encourage future work to constrain this further.

"Another highly debated area presently is the role of fjords in nutrient recycling, resulting in uncertainties in fluxes of glacial nutrients reaching the open ocean. Funding from the ERC (ICY-LAB) and the Royal Society is allowing us to continue research into this area, with projects considering biogeochemical cycling in Greenlandic fjords.

"We look forward to being able to shed light on these uncertainties by using a range of analyses from fieldwork within these fjord environments."
-end-


University of Bristol

Related Science Articles:

75 science societies urge the education department to base Title IX sexual harassment regulations on evidence and science
The American Educational Research Association (AERA) and the American Association for the Advancement of Science (AAAS) today led 75 scientific societies in submitting comments on the US Department of Education's proposed changes to Title IX regulations.
Science/Science Careers' survey ranks top biotech, biopharma, and pharma employers
The Science and Science Careers' 2018 annual Top Employers Survey polled employees in the biotechnology, biopharmaceutical, pharmaceutical, and related industries to determine the 20 best employers in these industries as well as their driving characteristics.
Science in the palm of your hand: How citizen science transforms passive learners
Citizen science projects can engage even children who previously were not interested in science.
Applied science may yield more translational research publications than basic science
While translational research can happen at any stage of the research process, a recent investigation of behavioral and social science research awards granted by the NIH between 2008 and 2014 revealed that applied science yielded a higher volume of translational research publications than basic science, according to a study published May 9, 2018 in the open-access journal PLOS ONE by Xueying Han from the Science and Technology Policy Institute, USA, and colleagues.
Prominent academics, including Salk's Thomas Albright, call for more science in forensic science
Six scientists who recently served on the National Commission on Forensic Science are calling on the scientific community at large to advocate for increased research and financial support of forensic science as well as the introduction of empirical testing requirements to ensure the validity of outcomes.
World Science Forum 2017 Jordan issues Science for Peace Declaration
On behalf of the coordinating organizations responsible for delivering the World Science Forum Jordan, the concluding Science for Peace Declaration issued at the Dead Sea represents a global call for action to science and society to build a future that promises greater equality, security and opportunity for all, and in which science plays an increasingly prominent role as an enabler of fair and sustainable development.
PETA science group promotes animal-free science at society of toxicology conference
The PETA International Science Consortium Ltd. is presenting two posters on animal-free methods for testing inhalation toxicity at the 56th annual Society of Toxicology (SOT) meeting March 12 to 16, 2017, in Baltimore, Maryland.
Citizen Science in the Digital Age: Rhetoric, Science and Public Engagement
James Wynn's timely investigation highlights scientific studies grounded in publicly gathered data and probes the rhetoric these studies employ.
Science/Science Careers' survey ranks top biotech, pharma, and biopharma employers
The Science and Science Careers' 2016 annual Top Employers Survey polled employees in the biotechnology, biopharmaceutical, pharmaceutical, and related industries to determine the 20 best employers in these industries as well as their driving characteristics.
Three natural science professors win TJ Park Science Fellowship
Professor Jung-Min Kee (Department of Chemistry, UNIST), Professor Kyudong Choi (Department of Mathematical Sciences, UNIST), and Professor Kwanpyo Kim (Department of Physics, UNIST) are the recipients of the Cheong-Am (TJ Park) Science Fellowship of the year 2016.
More Science News and Science Current Events

Trending Science News

Current Coronavirus (COVID-19) News

Top Science Podcasts

We have hand picked the top science podcasts of 2020.
Now Playing: TED Radio Hour

Processing The Pandemic
Between the pandemic and America's reckoning with racism and police brutality, many of us are anxious, angry, and depressed. This hour, TED Fellow and writer Laurel Braitman helps us process it all.
Now Playing: Science for the People

#568 Poker Face Psychology
Anyone who's seen pop culture depictions of poker might think statistics and math is the only way to get ahead. But no, there's psychology too. Author Maria Konnikova took her Ph.D. in psychology to the poker table, and turned out to be good. So good, she went pro in poker, and learned all about her own biases on the way. We're talking about her new book "The Biggest Bluff: How I Learned to Pay Attention, Master Myself, and Win".
Now Playing: Radiolab

Invisible Allies
As scientists have been scrambling to find new and better ways to treat covid-19, they've come across some unexpected allies. Invisible and primordial, these protectors have been with us all along. And they just might help us to better weather this viral storm. To kick things off, we travel through time from a homeless shelter to a military hospital, pondering the pandemic-fighting power of the sun. And then, we dive deep into the periodic table to look at how a simple element might actually be a microbe's biggest foe. This episode was reported by Simon Adler and Molly Webster, and produced by Annie McEwen and Pat Walters. Support Radiolab today at Radiolab.org/donate.