Microbial respiratory activity in several sites of the Ross sea was studied in the framework of the Italian National Research Programme in Antarctica (PNRA), with the aim of evaluating the biological pump efficiency and the carbon flux transported by microbes throughout the water column. Recent studies have demonstrated that dissolved organic carbon (DOC) is an important component of the biological pump that assumed in the deep waters a key role as main organic fuel of microbial respiration. Such evidence seem overturned in the Southern Ocean where DOC pool accounted for < 10 % of the remineralization in deep waters. Moreover the euphotic zone of the Ross Sea yielded only a small portion of primary production as DOC (11 %), so that DOC removal by deep convection could be not an important export term due to the small quantity of DOC that accumulates there. The purpose of this study was to investigate the supply and utilization of organic carbon in the aphotic zone of Ross Sea by evaluation of microplankton respiratory activity and to compare the vertical carbon balance with different estimates of export production from the same area and other oceanic regions.
Carbon dioxide production rates in the Ross Sea (Antarctica)
Maurizio Azzaro;Leonardo Langone;Giovanna Maimone;Rosabruna La Ferla
2015
Abstract
Microbial respiratory activity in several sites of the Ross sea was studied in the framework of the Italian National Research Programme in Antarctica (PNRA), with the aim of evaluating the biological pump efficiency and the carbon flux transported by microbes throughout the water column. Recent studies have demonstrated that dissolved organic carbon (DOC) is an important component of the biological pump that assumed in the deep waters a key role as main organic fuel of microbial respiration. Such evidence seem overturned in the Southern Ocean where DOC pool accounted for < 10 % of the remineralization in deep waters. Moreover the euphotic zone of the Ross Sea yielded only a small portion of primary production as DOC (11 %), so that DOC removal by deep convection could be not an important export term due to the small quantity of DOC that accumulates there. The purpose of this study was to investigate the supply and utilization of organic carbon in the aphotic zone of Ross Sea by evaluation of microplankton respiratory activity and to compare the vertical carbon balance with different estimates of export production from the same area and other oceanic regions.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
