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Working Group Updates
Working Group Updates
Biogeochemical Interactions at Deep-Sea Vents
Chair - N. Le Bris (IFREMER, France)
Members
The WG for Biogeochemical Interactions at Deep-Sea Vents
had one new change in membership for 2008: Huaiyang Zhou
has joined the IR WG for Deep Earth Sampling, and we invited
Xiqiu Han (Second Institute of Oceanography, China)
to join our WG in replacement. Xiqiu's expertise in oxygen
and carbon isotopic signatures of chemosynthetic processes fits
perfectly with the WG objectives, and she will bring a complementary
view from China.
IRTI
Many of our WG activities in this past year have been as a
follow-up to the InterRidge Theoretical Institute on Biogeochemical
Interactions at Deep-Sea Vents (Woods Hole, Sept.
10-14, 2007), with the help of the IR office, WHOI colleagues
and chairs of the discussion groups (see article in 2007 Inter-
Ridge Newsletter). Our workshop report is available at:
http://www.interridge.org/files/interridge/IRTI_2007_rept_
full_posted_NLB.pdf.
The development of original strategies and collaborative projects
was a main objective of the IRTI. Beyond smaller-scale
initiatives, the proposition for a coordinated action on an international
basis was issued from the workshop. A common
concern about the capacity of hydrothermal systems to derive
chemical energy to fix CO 2
into biomass arose from four of
the IRTI discussion groups (plume biogeochemistry, life in extreme
environments, hidden biosphere, long-term seafloor ecosystems
changes) and provided the basis for such an initiative.
Below, we highlight in particular two direct outcomes from
the IRTI:
- a SCOR proposal for a synthesis and modelling effort on
which a future large-scale biogeochemical flux experiment
will be based (developed from the several discussion groups
mentioned above), and
- interactions with the GEOTRACES program (another
SCOR-affiliated program) that developed more specifically
from the discussion group on plume biogeochemistry.
New SCOR Working Group
A major achievement of our WG in this past year is the approval
of a new SCOR Working Group, to be co-funded by
InterRidge, on "Hydrothermal energy transfer and its impact
on ocean carbon cycles." This new Working Group will be
co-chaired by Nadine Le Bris (IFREMER, France) and Chris
German (WHOI, USA). Currently, the proposal is posted
on the SCOR website at: http://www.scor-int.org/2008GM/
Ridges.pdf. We will also create a mirror webpage for this new
SCOR-InterRidge initiative as part of the on-going IR WG for
Biogeochemical Interactions at Deep-Sea Vents.
Hydrothermal venting is widespread throughout all ocean basins,
and the local fixation of carbon and the export of biolimiting
nutrients to the broader ocean may be much greater
than previously recognized. Recent advances in molecular
methods as well as in situ and in vivo experimentation now
provide us new opportunities for a coordinated, integrating effort
in which interdisciplinary approaches and modelling can
be proposed. The main objective is to set the basis for a revised
consideration of the diverse pathways of CO 2
fixation driven
by hydrothermal processes and the potential contribution that
they may make to the global ocean carbon cycle. Our new
SCOR support should allow larger initiatives to be organized
on this topic, involving a broader community of researchers,
including other IR WGs.
This is the first SCOR Working Group in over ten years to be
stimulated from InterRidge activities. We congratulate those
involved with the proposal and thank all who were involved
with the discussions at the IRTI. Please feel free to contact Nadine
(Nadine.Le.Bris@ifremer.fr), Chris (cgerman@whoi.edu),
or the InterRidge office (coordinator@interridge.org) with
questions or suggestions for the new SCOR Working Group.
Links with the GEOTRACES program
GEOTRACES is one of the newest SCOR-affiliated programs
and seeks to conduct a series of 2-D cross sections of the
oceans, spanning entire ocean basins, to characterize globalocean
biogeochemistry on scales comparable to the WOCE
program's physical oceanographic studies. In the USA the first
priority is a trans-North Atlantic geochemical section, currently
planned to be conducted in 2010, that will include one
station at the TAG hydrothermal mound. A second priority
for U.S. GEOTRACES, identified at a meeting held in Oct.
2008, will be to run a pair of sections in the eastern Pacific.
One will run from north to south between Alaska and Tahiti
and intercept dispersing hydrothermal plumes that span
the Pacific basin, emanating from (from North to South): the
Juan de Fuca Ridge, Loihi Seamount (Hawaii), East Pacific
Rise (EPR) 9-10°N and EPR 10-20°S. The complementary E-
W section will run between Tahiti and Peru, where the western
InterRidge News 44 Vol. 17, 2008