Stocks and dynamics of dissolved and particulate organic matter in the southern

• Main Author: Walker O. Smith
• Other Authors: The Pennsylvania State University CiteSeerX Archives
• Format: Text
• Language: English
• Published: 2000
• Subjects: Austral; Ross Sea; Antarc*; Antarctica
• Online Access: http://citeseerx.ist.psu.edu/viewdoc/summary?doi=10.1.1.391.8739; http://yyy.rsmas.miami.edu/groups/biogeochem/Hansell pdfs/28 Hansell.pdf

Dissolved and particulate organic matter was measured during six cruises to the southern Ross Sea. The cruises were conducted during late austral winter to autumn from 1994 to 1997 and included coverage of various stages of the seasonal phytoplankton bloom. The data from the various years are compiled into a representative seasonal cycle in order to assess general patterns of dissolved organic matter (DOM) and particulate organic matter (POM) dynamics in the southern Ross Sea. Dissolved organic carbon (DOC) and particulate organic carbon (POC) were at background concentrations of approximately 42 and 3 μM C, respectively, during the late winter conditions in October. As the spring phytoplankton bloom progressed, organic matter increased, and by January DOC and POC reached as high as 30 and 107 μM C, respectively, in excess of initial wintertime conditions. Stocks and concentrations of DOC and POC returned to near background values by autumn (April). Approximately 90 % of the accumulated organic matter was partitioned into POM, with modest net accumulation of DOM stocks despite large net organic matter production and the dominance of Phaeocystis antarctica. Changes in NO concentration from wintertime values were used to calculate the equivalent biological drawdown of dissolved inorganic carbon (DIC). The fraction of