Tuesday 14 August
5.15 pm in poster hall – Dr Johan Faust, ChAOS:
“Does sea ice reduction enhance preservation of organic carbon in Arctic marine sediments?”
Session 10b – Biogeochemical Cycling in Aquatic Sediments: Mechanisms, Environmental Controls and Responses to Change
Convenors: Sian Henley, Johan Faust, Silke Severmann, Robert Aller, Aninda Mazumdar, Wriddhiman Ghosh
Keynotes: John Crusius (U.S. Geological Survey), Carolina Reyes (University of Vienna)
Aquatic, especially marine, sediments are global sinks of organic carbon and hot-spots for the biogeochemical cycling of carbon, nutrients, metals and sulphur. Continental margins are regions of high organic fluxes and sediment accumulation rates, intense diagenetic cycling, sediment-water fluxes, and burial of biogenic and lithogenic debris. Integrated carbon-sulphur-iron cycling constitutes a key biogeochemical pathway in the cycling of redox sensitive elements and acts as an important control on the ultimate fate of carbon. The effects of climate change, such as decreasing sea-ice in the higher latitudes or changing precipitation patterns in drainage basins, have the potential to alter benthic cycling and the exchange between sediments and the water column significantly. In this session we will explore and contrast benthic biogeochemical cycling along continental margins and in other marine and lacustrine sedimentary settings from a range of climatic and weathering regimes, tectonic setting, sediment types, and oceanographic conditions. A central objective is to integrate geochemical records with live microbiome information so as to elucidate the characteristics, origin, processing, and fate of organic and inorganic carbon, nutrients and metals within the context of modern climate, oceanographic and ecosystem change from tropical to polar systems.