Biogeochemical Silicon Cycle in the South Pacific Ocean
My research focus on the biogeochemical silicon (Si) cycle using stable Si isotopes as a tool. For that, I work with seawater, particulate, marine pore waters and sediment samples.
Silicon (Si) is a major element and an important nutrient mainly for diatoms. Diatoms are important primary producers that take up dissolved Si from the water to build a siliceous skeleton and are responsible for the production of the majority of organic carbon in the oceans, which shows the importance of diatoms in both the global carbon and Si cycles. The stable Si isotope composition of different reservoirs like seawater or diatoms bears information on the dominant pathways and processes by which Si is transported to and cycled in the ocean. Additionally, the use of Si isotopes in pore waters can provide information about early diagenetic processes affecting the Si cycle in the sediments. Therefore, understanding the factors that control biogenic silica preservation has a vital importance for our general understanding of the global Si cycle.