Sea and Amundsen Gulf

• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Subjects: Arctic; Mackenzie River; Amundsen Gulf; Beaufort Sea; Mackenzie river; Phytoplankton
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.512.9607; http://www.ocgy.ubc.ca/~suttle/pubs/payet_suttle_2007.pdf

during the peak summer discharge, concomitant with a ~5.5-fold increase in chl a (up to 2.4 μg l−1) and a ~2-fold increase in bacterial abundance (up to 22×105 ml−1). Using FC, two subgroups of viruses and heterotrophic bacteria were defined. A low Available online at www.sciencedirect.com Journal of Marine Systems xx (2007) xxx–xxx MARSYS-01526; No of Pages 13 www.elsevier.com/locate/jmarsys ARTICLE IN PRESS⁎SYBR-green fluorescence virus subgroup (V2) representing ~71 % of the total viral abundance, was linked to the abundance of high nucleic acid fluorescence (HNA) bacteria (a proxy for bacterial activity), which represented 42 to 72 % of the bacteria in surface layers. A high SYBR-green fluorescence viral subgroup (V1) was more related to high chl a concentrations that occurred in surface waters during spring and at stations near the Mackenzie River plume during the summer discharge. These results suggest that V1 infect phytoplankton, while most V2 are bacteriophages. On the Beaufort Sea shelf, viral abundance displayed seasonal and spatial variations in conjunction with chl a concentration, bacterial abundance and composition, temperature, salinity and depth. The highly dynamic nature of viral abundance and its correlation with increases in chl a concentration and bacterial abundance implies that viruses are important agents of microbial mortality in Arctic shelf waters.