International Indian Ocean Science Conference(IIOSC)-2022

Abstract Submission No.	ABS-2022-10-0006
Title of Abstract	Reconstructing early diagenetic redox conditions by an amino acid based degradation indicator
Authors	Birgit Gaye^*
Organisation	Institute for Geology, University of Hamburg
Address	Institute for Geology, University of Hamburg, Bundesstraÿe 55 Hamburg, Hamburg, Germany Pincode: 22159 Mobile: 17637376854 E-mail: birgit.gaye@uni-hamburg.de
Country	Germany
Presentation	Oral
Abstract	Amino acids (AA) comprise the major proportion in fresh organic matter in the ocean and are also the main constituents identified by analytical techniques, in most oceanic particulate and dissolved organic matter pools. AA composition undergoes characteristic changes during organic matter degradation, making AA based biogeochemical indicators suitable to track decomposition processes. We analyzed AA data of a large set of samples covering sinking and suspended particles, sediments and water samples by a principal component analysis to test common degradation proxies and to better understand particle dynamics. This resulted in a new indicator of sinking particle and sediment degradation (SDI) which allows a fine tuned classification with respect to the intensity of degradation during early diagenesis in the water column and sediments. The SDI is furthermore sensitive to sedimentary redox conditions. We apply this proxy to reconstruct redox conditions in Holocene and Pleistocene sediments from the Arabian Sea.