DISSOLVED ORGANIC MATTER PRODUCTION AND MICROBIAL GROWTH AT STATION ALOHA
Oceans are estimated to be responsible for up to half of global primary production. Much of our understanding of temporal variability in ocean biogeochemical cycling comes from ongoing time-series observations, including the Hawaii Ocean Time-series (HOT). Twenty-five years of carbon fixation measurements, assessed by 14C bicarbonate assimilation, have provided improved understanding of carbon cycling in the North Pacific Subtropical Gyre. This presentation will describe 5 years of near-monthly measurements of rates of particulate and dissolved primary production at this time-series site, providing new insight into seasonal variability associated with primary production. Over the time series, dissolved productivity averaged approximately 25% of total (dissolved+particulate) production. Despite a well-resolved seasonal pattern in particulate production, dissolved productivity did not demonstrate the same seasonality. Coincident measurements of heterotrophic bacterial production suggested that bacterial production did not temporally co-vary with changes in primary production. These results highlight the complexity of processes likely contributing to production and consumption of dissolved organic matter in this habitat.
Viviani, D. A., University of Hawaii at Manoa, USA, email@example.com
Church, M. J., University of Hawaii at Manoa, USA, firstname.lastname@example.org
Time: 16:00 - 18:00
Location: Poster/Exhibit Hall
Presentation is given by student: Yes