scholarly journals Mississippi River Plume Enriches Microbial Diversity in the Northern Gulf of Mexico

2016 ◽  
Vol 7 ◽  
Author(s):  
Olivia U. Mason ◽  
Erin J. Canter ◽  
Lauren E. Gillies ◽  
Taylor K. Paisie ◽  
Brian J. Roberts
Keyword(s):  
Gulf Of Mexico ◽  
Microbial Diversity ◽  
Mississippi River ◽  
River Plume ◽  
Northern Gulf Of Mexico ◽  
Mississippi River Plume

Influence of the Mississippi River plume and non-bioavailable DMSP on dissolved DMSP turnover in the northern Gulf of Mexico

2016 ◽  
Vol 13 (2) ◽  
pp. 280 ◽  
Author(s):  
Jessie Motard-Côté ◽  
David J. Kieber ◽  
Allison Rellinger ◽  
Ronald P. Kiene
Keyword(s):  
Gulf Of Mexico ◽  
Mississippi River ◽  
Heterotrophic Bacteria ◽  
River Plume ◽  
High Productivity ◽  
Northern Gulf Of Mexico ◽  
Bioavailable Fraction ◽  
Mississippi River Plume ◽  
Consumption Rates ◽  
Louisiana Coast

Environmental contextDimethylsulfoniopropionate (DMSP) comprises an important fraction of the organic carbon produced by phytoplankton, and is a major source of carbon and sulfur for heterotrophic bacteria. Here, we show that a non-bioavailable fraction of DMSP recently discovered in coastal waters also exists in oligotrophic open-ocean waters. Taking account of the non-bioavailable pool improved estimates of cycling rates of DMSP and its contribution to bacterial nutrition. AbstractMicrobial cycling of dissolved dimethylsulfoniopropionate (DMSPd) and the fate of DMSP-sulfur were measured in the northern Gulf of Mexico off the Louisiana coast in September 2011 using the tracer 35S-DMSPd. Salinity ranged from 31.2ppt in the Mississippi River plume to 36.5ppt offshore. Total DMSP concentrations were significantly higher at the river-influenced stations (12–27nM) than offshore (6–14nM). From 8.7 to 27% of the measured DMSPd, equivalent to 0.1 to 0.23nM, was refractory (i.e. non-bioavailable). We subtracted refractory DMSPd from the measured DMSPd concentrations when calculating DMSPd consumption rates with the tracer 35S-DMSPd. DMSPd consumption and bacterial production were respectively 8 and 7 times higher in the river plume compared with offshore. Incorporation of DMSP-sulfur into biomass was almost three times higher in river-influenced water, whereas the dimethylsulfide (DMS) yield was 3.5 times lower in the river plume compared with offshore. Accordingly, DMSP contributed over 3 times more to the bacterial demand for both carbon and sulfur in the river-influenced water. Despite lower DMS yields in the river plume, the fast DMSP turnover resulted in a 2.7-times higher DMS production compared with offshore waters. Mississippi River inputs and the resulting high productivity led to a rapid turnover of DMSP and high DMS production in the river plume compared with oligotrophic Gulf of Mexico waters. Failure to account for refractory DMSPd when using the 35S-DMSP method will lead to significant overestimation of the DMSPd turnover flux and its contributions to C and S cycling.

scholarly journals Storm-induced injection of the Mississippi River plume into the open Gulf of Mexico

2004 ◽  
Vol 31 (9) ◽  
pp. n/a-n/a ◽  
Author(s):  
Jinchun Yuan ◽  
Richard L. Miller ◽  
Rodney T. Powell ◽  
Michael J. Dagg
Keyword(s):  
Gulf Of Mexico ◽  
Mississippi River ◽  
River Plume ◽  
Mississippi River Plume

Amino acid cycling in the Mississippi River Plume and effects from the passage of Hurricanes Isadore and Lili

2014 ◽  
Vol 136 ◽  
pp. 10-21 ◽  
Author(s):  
Thomas S. Bianchi ◽  
Bryan L. Grace ◽  
Kevin R. Carman ◽  
Ivan Maulana
Keyword(s):  
Amino Acid ◽  
Mississippi River ◽  
River Plume ◽  
Mississippi River Plume
Sign in / Sign up

Export Citation Format

Share Document