Goldschmidt Conference 2009

Goldschmidt™ 2009 - "Challenges to Our Volatile Planet"
June 21 - 26 in Davos, Switzerland
http://www.goldschmidt2009.org/index
Contributions from IR-SCOR Working Group listed below

Theme 16: Life at the Edge: Extreme Environments
Co-ordinators:
Samantha (Mandy) Joye (University of Georgia)
Antje Boetius (Max Planck Institute for Marine Microbiology)
Team members:
Katrina Edwards (University of Southern California), Nadine Le Bris (IFREMER), Ron Oremland (US Geological Survey), Anna-Louise Reysenbach (Portland State University), Andreas Teske (University of North Carolina)
Scope of theme:
Geofluids and life (hydrothermal vents, methane seeps, brines), Microbial communities in rock-dominated environments, Survival on a permanent diet (deep biosphere), Origin of life and biosignatures, Life at the fringe (microbial diversity and activity in contaminated sites), Thermodynamic and kinetic limits on geomicrobial activity, Life in deep cold environments (Polar lakes), Exobiology.

16b: Pathways and Regulation of Energy and Carbon Transfer in Deep-Sea Extreme Environments
Convenors: Stefan Sievert, Nadine Le Bris
Keynote: Costantino Vetriani (Rutgers University)
Some of the most extreme environments on Earth are found in the deep-ocean (hydrothermal vents, methane and hydrocarbon seeps, hypersaline lakes). They exhibit tremendous variability in a number of physico-chemical parameters, including temperature, pH, gas (H2S, CO2, CO, O2) and heavy metal concentrations, and other potentially harmful chemicals. Yet they are among the most productive marine environments. Key processes sustaining deep-sea chemosynthetic communities have been highlighted (chemolithoautotrophy, symbiosis) but the wide range of biogeochemical pathways arising from the variety of redox conditions, and the complexity of energy transfer mechanisms from molecules to organisms remain to be described. Availability of chemical substrates and energy budgets, diversity of carbon fixation pathways, adaptability of symbioses, interactions between invertebrates and biogeochemical processes, and large-scale impact of these processes are major issues for which recent interdisciplinary studies and new analytical capabilities have allowed significant advances. These new insights provide a better understanding of the underlying mechanisms sustaining the high productivities of these ecosystems and their potential impact on global element cycling.

A Geochemical and Microbiological Analysis of Nitrate Reduction at a Hydrothermal Vent and at a Cold Seep M. W. BOWLES AND S. B. JOYE

Detecting Total Dissolved Sulfide anomalies in marine sediments using XRF core scanner J. ETOUBLEAU, J.-C. CAPRAIS, G. BAYON, D. BIROT, L. RUFFINE, P. PIGNET, B. DENNIELOU

Fatty-acids and their 13C signatures in seep carbonates from hydrocarbon seeps on the upper (GC 185) and lower (AC 645) continental slope of the Gulf of Mexico H. X. GUAN, D. FENG, N. Y. WU AND D. F. CHEN

Archaeal and bacterial diversity and distribution in methane seep of Yung-An Ridge, SW Taiwan M. C. LAI, J. Y. DING, S. Y. WU, C. C. HUNG, S. J. LAI, S. LIN, T. F. YANG

Organism-environment interaction and the productivity of chemosynthetic communities at hydrothermal vents N. LE BRIS

Methanethiol: a geochemical link between carbon and sulfur in hydrothermal systems?
EOGHAN REEVES AND JEFFREY S. SEEWALD

(Meta)genome Enabled Insights into Chemolithoautotrophy at Deep-Sea Hydrothermal Vents STEFAN M. SIEVERT, CRAIG D. TAYLOR, STEPHAN C.
SCHUSTER, LARA K. GULMANN

Benthic respiration and energy transfer in cold seep habitats S. SOMMER , P. LINKE, O. PFANNKUCHE, H. NIEMANN, T. TREUDE, M. HAECKEL

Deep ocean interactions between hydrothermally-sourced iron and organic carbon.
BRANDY M. TONER, SARAH A. BENNETT, NAN-CHIN CHU, AND CHRISTOPHER R. GERMAN

From whale to chemosynthesis: energy and carbon fluxes at a deepsea whale fall
TINA TREUDE, CRAIG R. SMITH, FRANK WENZHÖFER, ERIN CARNEY, ANGELO F.
BERNARDINO, ANGELOS K. HANNIDES, MARTIN KRÜGER, ANTJE BOETIUS

Microbial Mechanisms of Energy Conservation, Carbon Transfer and Detoxification in Deep-Sea Extreme Environments (Keynote) COSTANTINO VETRIANI

Metagenomics assisted investigations of the Metabolic Diversities of Microbial Communities in the chimneys at Juan de Fuca Ridge FENGPING WANG, HUAIYANG ZHOU, JUN MENG, CHUANLUN ZHANG,JIZHONG ZHOU, WEI XIE, ANLONG XU NING ZHOU, AND XIANG XIAO

Compositional and functionaltransition in epibiotic symbionts of Shinkaia crosnieri: Morphology,Structure, Energy and Carbon Metabolisms during rearing TOMORO WATSUJI AND KEN TAKAI

Post-eruption sulfide and iron content of hydrothermal vent fluids from East Pacific Rise, 9°50’ N MUSTAFA YÜCEL*, KATHERINE M. MULLAUGH AND GEORGE W. LUTHER, III

Please note that abstracts were published in a special edition of GCA (Geochimica et Cosmochimica Acta), Volume 73, Issue 13 Supplement 1 (June 2009). http://www.goldschmidt2009.org/abstracts/view

16f: Life in the Deep Dark Subsurface Biosphere
Convenors: Peter Girguis, Julie Huber
Recent studies show that oceanic crust and sediments host extensive but poorly characterized microbial communities. Data suggest these are the largest microbial communities on Earth, and accordingly, there is continuing debate about the extent and impact of this deep biosphere.
This session will examine these issues, highlighting results of novel and interdisciplinary approaches to studying the subsurface biosphere, and examining the role of interdisciplinary approaches to studying microbial processes. This session will specifically focus on the recent and significant advances that provide insight into the physiological potential and activity of these communities. These and other findings have been enabled by recent advances in techniques and technologies, from metagenomics to bioenergetic modeling, and will constitute the basis of our discussion.

Other sessions included:
4c: Hydrothermal processes at mid-ocean ridges: temporal and spatial variability and impacts on biogeochemical cycling between mantle, crust, and ocean
Convenors: Hedy Edmonds (UT), Julie Bryce (UNH), Marv Lilley (UW), Adelie Delacour (IPGP), Marguerite Godard (U. Montpelier)
Keynote Speaker: Andrea Koschinsky
Session Description: The numerous hydrothermal systems discovered along mid-ocean ridges during the last decades have underscored the importance of seawater circulation and alteration processes in crustal and mantle-dominated lithosphere as means of mass and energy transfers in oceanic accretion zones. Hydration of the cooling lithosphere results in a series of strongly interconnected thermal, chemical, and biological processes within and upon the seafloor, which contribute significantly to biogeochemical budgets throughout the Earth-ocean system. Throughout her career, Karen Von Damm provided many insights into these significant processes by studying temporal and spatial variations in mid-oceanic ridge hydrothermal systems. In celebration of her legacy, we encourage contributions from all who seek to shed light upon the geological, geochemical and biological processes active at mid-oceanic ridge spreading centers.