Award: OCE-1635893

Impacts The marine carbon cycle is one of the most fundamental biogeochemical pathways on earth and is linked to many other elemental cycles. As such, the processes and mechanisms of this cycle have far reaching implications on the biosphere and climate systems, and consequently have been thoroughly studied over decades. However, the potential importance of NICP as a CaCO3 formation pathway has received very little attention, with previous studies limited to experiments in the laboratory and carbonate-rich environments (e.g., CaCO3 sediments). At present, the role of NICP in the marine carbon cycle is unknown. In addressing this knowledge gap, this project will have a number of impacts: 1) This is the first study to examine the mechanisms and significance of in-situ NICP in non-carbonate rich coastal environments and will therefore fill a knowledge gap in our understanding of the carbon cycle. 2) The study uses a comprehensive approach, including field observation, in situ mesocosm experiments, lab-controlled experiments, and modeling, to gain in-depth understanding of the factors controlling NICP, and the impact of NICP, in different environments with different sediment sources. 3) The project results directly contribute to the US Coastal Carbon Synthesis activities by providing a carbon flux estimate of a previously ignored process in the Gulf of Mexico. This interdisciplinary project brings together investigators from three institutions in two countries, with expertise in carbonate chemistry and sensor development (Wang, WHOI), sediment dynamics and modeling (Churchill, WHOI), CaCO3 biogeochemistry (Wurgaft, postdoc of this project), coastal marine sedimentology (Dellapenna, Texas A&M University), and sediment diagenesis and isotope geochemistry (Lazar, HUJI). Carbonate minerals constitute an important source for paleo-oceanographic data. Therefore, if NICP is proven significant in various coastal environments, the project results will be important for both contemporary marine carbon cycle research and paleo-oceanography studies. Since the role of NICP in the oceanic carbon cycle has never been studied in common oceanic settings, we expect this study to stimulate extensive future research on NICP, which would extend beyond chemical oceanography to other disciplines of oceanographic and geochemical research, such as paleo-oceanography and sediment diagenesis. The collaboration among scientists from HUJI, WHOI and Texas A&M University has strengthened scientific collaboration and exchange between these research institutions. This project allows each institution access to sampling sites with different sediment sources and processes (the GoA and the nGoM) as well as to a wider range of analytical equipment and sensors, thus broadening research scope and reducing overall cost. This project has integrated research with education and promoted teaching and training of new scientists through the following activities: (1) Dr. Eyal Wurgaft, whose PhD study formed the foundation of this study, worked as a co-PI/postdoc on the project. He gained the leadership and independence through this project, which will prepare him to become a world-class carbonate chemist. (2) We engaged two undergraduate students, including a minority REU fellow, through the WHOI summer education fellowship. (3) Diverse group of undergraduates from TAMUG have participated in the cruise to the nGoM as part of Dellapenna’s Modern Oceanographic Methods Field course as well as his Geological Oceanography and Coastal Processes courses. (4) Project findings are being incorporated into courses taught by project PIs and postdoc. Lazar is adding this project’s findings to the syllabus of "Introduction to Geochemistry" and "Chemical Oceanography" courses at HUJI. @font-face {font-family:"Cambria Math"; panose-1:2 4 5 3 5 4 6 3 2 4; mso-font-charset:0; mso-generic-font-family:roman; mso-font-pitch:variable; mso-font-signature:-536870145 1107305727 0 0 415 0;}@font-face {font-family:Calibri; panose-1:2 15 5 2 2 2 4 3 2 4; mso-font-charset:0; mso-generic-font-family:swiss; mso-font-pitch:variable; mso-font-signature:-469750017 -1073732485 9 0 511 0;}p.MsoNormal, li.MsoNormal, div.MsoNormal {mso-style-unhide:no; mso-style-qformat:yes; mso-style-parent:"; margin-top:0in; margin-right:0in; margin-bottom:10.0pt; margin-left:0in; line-height:115%; mso-pagination:widow-orphan; font-size:11.0pt; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:"Times New Roman"; mso-fareast-theme-font:minor-fareast; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi; mso-fareast-language:ZH-CN;}.MsoChpDefault {mso-style-type:export-only; mso-default-props:yes; font-family:"Calibri",sans-serif; mso-ascii-font-family:Calibri; mso-ascii-theme-font:minor-latin; mso-fareast-font-family:Calibri; mso-fareast-theme-font:minor-latin; mso-hansi-font-family:Calibri; mso-hansi-theme-font:minor-latin; mso-bidi-font-family:"Times New Roman"; mso-bidi-theme-font:minor-bidi;}div.WordSection1 {page:WordSection1;} Last Modified: 05/21/2021 Submitted by: Timothy M Dellapenna