Ground-truthing paleo-proxy calibrations in Desmophyllum dianthus deep-sea corals using long-term aquaria cultures

• Main Authors: Martínez-Dios, Ariadna, Ko, Stanley, Sherrell, Robert M., Pelejero, Carles, Kozdon, Reinhard, López-Sanz, Àngel, Calvo, Eva María, Lucas, Arturo
• Other Authors: Generalitat de Catalunya, National Science Foundation (US), Fundación Endesa, Consejo Superior de Investigaciones Científicas (España), Fundación San Ignacio del Huinay, Ministerio de Ciencia, Innovación y Universidades (España)
• Format: Still Image
• Language: unknown
• Published: American Geophysical Union 2018
• Subjects: Southern Ocean
• Online Access: http://hdl.handle.net/10261/192716; https://doi.org/10.13039/100000001; https://doi.org/10.13039/501100002809; https://doi.org/10.13039/501100007827; https://doi.org/10.13039/501100003339; https://doi.org/10.13039/501100007829

American Geophysical Union Fall Meeting, 10-14 December 2018, Washington D.C.-- 1 page Deep-sea corals (DSCs), similar to their tropical counterparts, potentially provide continuous, high-resolution records of surrounding seawater conditions for up to a century or more. Several CWC elemental and isotopic ratios have been suggested as useful proxies of past oceanic conditions, for example for temperature, nutrients and CO2 system parameters. So far, however, such proxies have only been calibrated using modern seawater variations in the field, where inevitably properties of interest co-vary. In order to better constrain their use, robust calibrations under controlled conditions in aquaria are needed. This kind of experiment is rare, however, given the technical challenges involved in maintaining these slow-growing animals alive during the long-term experiments required to achieve sufficient skeletal growth for geochemical analyses. We will show details of the setup and the current status of a long-term experiment being run at the ICM (Barcelona), where live specimens (~130) of Desmophyllum dianthus collected from Comau Fjord (Chile) are kept under controlled and manipulated parameters (temperature, pH, phosphate, barium, cadmium) and feeding frequency. With this setup, in combination with geochemical analysis of the coral skeletons using Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS), we aim to calibrate specific elemental ratios including P/Ca, Ba/Ca, Cd/Ca, ¿11B, B/Ca, U/Ca and Li/Mg as proxies of nutrient dynamics, pH, carbonate ion concentration and temperature, respectively. Data obtained so far from this experiment will be presented, together with preliminary geochemical data on fossil corals from different regions, including the Southern Ocean and the Mediterranean Sea Financial support is acknowledged from CSIC, Endesa Foundation, San Ignacio del Huinay Foundation, Spanish Ministry of Science, Innovation and Universities, Catalan Government and the National Science Foundation ...