Project: Constraining past variations in the global biogeochemical silica cycle
Silica biomineralization in the oceans has affected evolutionary competition for dissolved Si, and this has resulted in changes in the global biogeochemical cycles of silica, carbon and other nutrients that regulate oceans productivity and climate. The major goal of this project is to create new knowledge of the interactions between biosilicification in organisms and the environment and how these interactions have evolved through Earth’s history.
Facts about the project
Project manager at Linnaeus University Jarone Pinhassi, Hanna Farnelid, Daniel Lundin Project manager at Lund University Daniel Conley Other project members at Linnaeus University Camilla Karlsson, Mellat Solomon, Evangelia Charalampous, Anabella Aquilera Other project members at Lund University Sylvain Richoz, Franziska Stamm, Yuhao Dai, Tjördis Störling, Karolina Brylka Participating organizations Linnaeus University, Lund University Financier Knut och Alice Wallenbergs Stiftelse Timetable 1 jan 2019 - 31 dec 2023 Subject Microbiology (Department of Biology and Environmental Science, Faculty of Health and Life Sciences) Research group Marine microbiology
More about the project
It is widely recognized that the emergence and expansion of silica biomineralization in the oceans has affected evolutionary competition for dissolved Si (DSi). This resulted in changes in the global biogeochemical cycles of silica, carbon and other nutrients that regulate ocean productivity and ultimately climate.
However, a series of very recent discoveries in geology and biology suggest that the first biological impacts on the global Si cycle were likely by prokaryotes during the Archean with further decrease in oceanic DSi with the evolution of widespread, large-scale skeletal biosilicification significantly earlier that the current paradigm. Three critically important time periods when large-scale changes in Si-cycling occurred will be investigated; 1) the transition from bacterial to eukaryotic marine primary productivity in the Meso- and Neoproterozoic, 2) the role of stramenopiles, including diatoms, in changing oceanic DSi concentrations starting in the lower Mesozoic, and 3) the impact of changing DSi inputs on the Cenozoic oceans.
The major goal of this project is to understand the interactions between biosilicification in organisms and the oceans and how these interactions have evolved through Earth’s history until today. In the modern oceans the availability of DSi controls the amount of diatom primary productivity, which today account for 20% of the world’s primary production- Therefore, understanding the mechanisms of the past and present regulation of oceanic DSi and the interactions with other key biogeochemical cycles is critically important to understanding climate and food webs.
We will utilize state of the art stable isotope measurements of biosilicification in fossil material from deep time coupled with an exploration of the role of the three major groups of extant eukaryotic phytoplankton (cyanobacteria, diatoms and dinoflagellates) under a number of different ecologically relevant conditions present in the ancient oceans. It is through this unique combination of novel analyses of the geological record coupled with experimental biological investigation of key prokaryotes and silicifying eukaryotic phytoplankton groups that we will achieve a new understanding of the functioning of the Earth’s oceans through geological time.