Microbial processes in the subarctic northeast Pacific : bacterial standing stocks, rate processes, and controls ...

• Main Author: Sherry, Nelson Daniel
• Format: Text
• Language: English
• Published: University of British Columbia 2009
• Subjects: Subarctic
• Online Access: https://dx.doi.org/10.14288/1.0052771; https://doi.library.ubc.ca/10.14288/1.0052771

During 11 cruises along the east/west line-P transect from slope waters at P4 (1200 m depth) to the open-ocean waters at Ocean Station Papa (OSP) (4250 m depth), heterotrophic bacterial abundance, productivity, and respiration rates were measured. While values from below the euphotic zone (-60 - 4200 m) are reported, detailed analysis is focused primarily on the euphotic zone. Within the euphotic zone, bacterial biomass in the winter was -50% of the spring and summer values. Bacterial respiration rates in the summer increased > 10-fold at P4 while showing much less change at the more oceanic stations. Bacterial productivity, measured as [ H]-thymidine and [14C]-leucine incorporation rates, was lowest in the winter with little spatial variability. Productivity increased 4 to 10-fold in spring at P4. Between 1995 and 1998, the average summer bacterial abundance along line-P decreased by -50% while bacterial productivity decreased by - 90%. Factors for converting the incorporation of radiolabeled substrate ...