COBR-2023-April

We plan to carry out a series of seasonal cruises to improve and expand the published biogeochemical characterizations of the hypersaline Orca Basin, focusing specifically on sulfur and carbon cycling. This cruise will be our first expedition to the proposed field site. We plan to collect water samples via Niskin bottles on the ship's rosette to estimate the distributions of various compounds (e.g.: HS-, DOC, POC, CH4, NH4, etc) throughout the upper water column, the basin salinity gradient, and within the hypersaline basin. We will conduct shipboard experiments will basin water to measure rates of microbial methane oxidation. We will further sample the hypersaline sediments with a box core to collect an in-situ microbial community for lab-based incubation studies. This sampling scheme will inform future work in Orca Basin analyzing degradation and sulfurization rates of terrestrial biomass deployed via a benthic lander.