Metal contamination free science on a metal ship: trace metal saga
Main characters: The Incredible Team Iron
Protagonists:
Maeve Lohan
(University of Plymouth)
Antony Birchill
(University of Plymouth)
Dagmara Rusiecka
(University of Southampton/Geomar, Kiel)
Amber Annett (University
of Edinburgh)
Antagonists:
Metal contamination
(Everywhere)
. / .
DY029 Fe transect trilogy by Dagmara Rusiecka (University of Southampton/Geomar, Kiel): The return of the Team Iron
It’s been less
than four months since DY018 and ‘Team Iron’ is back on board RRS Discovery
waiting with excitement for the first cast of the first iron transect…
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Encouraging message from the Team Iron fan club onboard. Photo by Chata |
April the 7th, 11PM, kick off: Team Iron is all dressed up in clean white Tyvek suits and white mop hats rushing around in the clean sampling lab. 24 grey bottles designed specifically for the trace metal sampling returned from 2500m and with gloved taps were very quickly transferred from the deck to the clean lab to minimize the risk of metal contamination. Now, they’re racked on the wall, safe, secured and ready for a solid 4 hour sampling session. Team Iron wearing ‘dirty’ gloves is tackling through sample bottles for other scientists; DOM (dissolved organic matter), SPM (suspended particulate matter), alkalinity, flow cytometry, chlorophyll a, oxygen, salinity. Finally, it’s time for the ‘clean’ gloves and the ‘clean’ samples!
In meantime, outside
of the clean lab, Amber Annett is already waiting for the stainless steel rosette
to return on deck with 480L of seawater just for Ra (Radium) isotope measurements
at only a few depths! In plastic cubic containers she’s carrying 20L of
seawater one by one on her shoulder to her container. She’s not only strong but
also a lucky girl. No need to worry about the metal contamination but hey, she
needs liters of seawater to detect the short-lived Ra 224 isotope! Therefore,
the rosette is deployed again for another round and more water for Amber.
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Team Iron in the zone of discussing results from DY018. Photo by Jose Lorenzo |
1AM: All geared up with clean sampling clothing. Team Iron is tackling through ‘clean’ sample bottles. 5 liters for chromium isotopes, 1 liter for iron isotopes, 500 ml for copper speciation ……. It’s time for their own samples. 250 ml for iron speciation, one 125ml bottle for trace metals and one 125ml bottle for iron.
3 AM: Team Iron is
packing samples from the first cast whilst the ship is already at the next station
and the crew is ready for the next cast. “Here we go again guys! 6 stations to
go!” and the process is starting all over again.
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Rare and short appearance of 'Rosie' the trace metal clean titanium rosette with bottles on deck. Still with gloved taps, almost ready for the deployment. Photo by Dagmara Rusiecka |
Coming up soon:
Volume two: The Two transects
Volume three: The Fellowship of the Iron: Final transect
So why do we do what we do?
As some of you may
know, iron is an essential micronutrient to marine organisms present at very
low concentration. It influences
phytoplankton productivity, community structure and ecosystems and is a
limiting factor on primary production in some regions. Our aim is to capture
the mechanisms of iron off-shore transport to the open ocean that currently are
unknown.
