Andrew Presley, University of Rhode Island


The Silica cycle and the biological pump in our global oceans are intimately related. As a part of the NASA Export Processes in the Ocean from Remote Sensing (EXPORTS) our work aims to explore the community composition of picoplankton in the 0.2-5µm size fraction and their contributions to the silica cycle using next generation MiSeq sequencing and analysis. Recently published data from collaborators within the EXPORTS project have observed high biogenic silica production in the picoplankton, indicating that organisms in this size fraction are contributing notably to the silica cycle in the North Pacific, though it remains unclear exactly what organisms are responsible. During our analysis we have also pioneered the use of an internal DNA reference within the picoplankton for the calculation of absolute sequence abundance, as well as the reduction of sequencing, PCR and DNA extraction variability in community analyses. By pioneering this method in our analysis, we hope to create an example for future labs both within the EXPORTS group as well as the Oceanographic community as a whole to utilize in their analyses going forwards to better allow collaboration and comparison of community analysis work.