C-DEBI Newsletter – February 3, 2014

• Session 19a: Biomodulation: Do Organisms Drive Biogeochemical Cycles or Vice-Versa?Conveners: Hope Jahren, Jen Biddle, Uwe Balthasar, Stephan Hättenschwiler
  Keynote Speaker: Jake Bailey
         Globally cycled elements such as carbon, nitrogen, phosphorous, magnesium, iron (and many others) are also critical to the life processes of organisms. As organisms acquire and metabolize these chemical resources, the biogeochemical cycling of the elements is affected on local-to-regional-to-global scales. At the same time, the relative abundance of these elements is a major driver of biological evolution and is at the origin of much of the global biodiversity. This session is meant to explore feedbacks between biogeochemical cycles and the evolution and alteration of life forms on Planet Earth through time, and within today’s changing environment. We welcome work that highlights the interactive effects of changing biogeochemical cycles and the activity and diversity of evolving living organisms. We are interested in highlighting contributions discussing plants, animals, and microbes; we are also interested in discussing marine, freshwater, and terrestrial ecosystems at multiple spatial and temporal scales. Related phenomena within extreme and extraterrestrial environments are also welcome. Specific examples of subjects that could be explored include (but are not limited to) the following: The effect of plants on weathering, the effect of soil animals on nutrient cycling, the effect of anthropogenically-induced changes in elemental cycles upon species distribution and ecosystem functioning, the relationship between geologic cycles and microbial community structure, the role of metabolites in climate, the feedbacks between animals, plants and microbes, the evolution of organism strategies to cope with shortage of elements.
   
• Session 18b: Life at Limits
  Conveners: Jan Amend, Dirk de Beer
         Microbial life is found under a remarkably wide range of environmental conditions. Microorganisms can live under energy and nutrient limitations, with extreme pH levels, temperatures, salinities, pressures and radiation conditions, and combinations thereof, where organisms that inhabit more common habitats cannot survive. But eventually all life on Earth (and elsewhere) has its limits. By studying life at the extremes, as well as the geochemical conditions on both sides of the biotic:abiotic divide, we can gain a better understanding of particular adaptations for harsh situations in terrestrial and extraterrestrial environments.  This session will feature recent discoveries in microbiology, geochemistry, and related disciplines that focus on archaea and bacteria that may thrive or merely eke out a living under apparently difficult conditions.  We invite contributions that employ field, laboratory, and/or modeling approaches and encourage the authors to interpret their findings in a global context. In particular, we invite scientists to present data on environments where they found no signs of life or microbial conversions, despite the presence of thermodynamic disequilibria. This is fascinating, as it allows exploring the boundaries beyond which no life is possible. We would like to encourage you to submit an abstract to what promises to be an exciting session.
   
• Session 25b: Microbial Signatures in Sedimentary Organic Matter and the Deep Biosphere
  Conveners: Helen Marie Talbot, Julius Lipp, Kai Hinrichs, and Karen Lloyd
  Keynote Speaker: Ann Pearson
         A vast array of organic geochemical biomarker and isotopic proxies are available to investigate modern and past signatures of microbialy mediated biogeochemical cycles from pigments indicative of bacterial and algal photosynthesis to highly specific lipids indicating processes such as anaerobic ammonium oxidation or methane oxidation, to RNA, extra- and intracellular DNA, and functional protein assays. In this session we will cover signatures from all forms of microbial life (eukaryotes, bacteria and archaea) covering both aerobic and anaerobic processes from shallow, recent sedimentary environments to ancient and deeply buried subseafloor systems. We particularly welcome talks exploring novel applications offering new insights into the complex roles of microorganisms in regulating biogeochemical cycles through geological time in either terrestrial or marine sedimentary environments.
   
• Session 18f: Life and Death: Molecular Biomarkers to Study Current and Past Ecosystems
  Conveners: Marco Coolen, Laura Epp, Jen Biddle, Casey Hubert, Bente Lomstein
  Keynote Speaker: William D. Orsi
         Molecular biomarkers such as RNA, DNA, lipids, and proteins are used to study currently living environmental organisms that have never been cultivated as well as past organismal assemblages. In this session we seek to explore novel methodological developments using molecular biomarkers in both aquatic and terrestrial environments. How can we discriminate molecular signatures of active, dormant and fossil life? How do taphonomical processes after death change these signatures? How do dormant organisms – or spores – help shape biogeography and biogeochemical functions? What novel insights can be achieved by the inclusion of (ancient) DNA into studies of historical biodiversity? In particular, we welcome studies which combine different biomarkers to address methodological questions and to provide a highly detailed picture ecosystem structure and it’s changes with a special focus on the Holocene.
   
• Session 05f: Serpentinization Processes: From Mantle to Microbe, Past and Present
  Conveners: Susan Lang, Muriel Andreani, Tom McCollom
  Keynote Speaker: Tori Hoehler
         This session seeks to bring together scientists from a range of backgrounds to discuss the many different aspects of serpentinization and its geophysical, geochemical, and biological consequences. Serpentinites are widespread in both oceanic and continental lithospheres on Earth, and likely occur in a number of other planetary bodies in the solar system as well. The formation of serpentinites through hydration of ultramafic rocks plays a role in many other processes, including the geophysical and geochemical evolution of the ocean crust from ridges to subduction zones, transfer of elements and volatiles to overlying rocks and seawater, production of reduced compounds that support chemosynthetic microbial communities in surface and subsurface settings, sequestration of CO₂ in carbonate minerals, and abiotic synthesis of methane and other organic compounds. Serpentinites have contributed to these processes throughout Earth’s history, and perhaps provided a setting for the evolution of the earliest forms of life. We invite contributions concerning these and other topics related to serpentinization, including field, laboratory, and theoretical studies. Contributions that explore links between the geophysical, geochemical, biological, and astrobiological aspects of serpentinization are especially encouraged.

The 3rd International Conference of Geobiology, June 16-18, 2014, Wuhan, China
Registration deadline is Feb 28, 2014.