Relative contribution of different seston components to ascidian food in Potter Cove

TATIÁN, MARCOS; MILOZZI, CAROLA; SAHADE, RICARDO; MERCURI, GUILLERMO; LAGGER, CRISTIAN

Berichte zur Polar-und Meeresforschung /Reports on Polar and Marine Research

Alfred Wegener Institute

Lugar: Bremerhaven; Año: 2008 p. 128 - 134

1618-3193

The particle dynamics of the water-column bottom layer within Potter Cove are important to suspension feeders at different distances from the bottom. Organic particles (macroalgal detritus) with a lower specific mass than inorganic particles (sand and part of the fecal pellets), will be suspended for a longer period of time and be present at a greater distance from the bottom. Therefore, these particles are mainly available for erected fauna throughout the year. On the other hand, some depressed shape ascidians as C. eumyota appear to be adapted to withstand the inorganic particles from the intense sedimentation. This study revealed that both species retain a wide range of particle sizes and quality (< 5 μm to 1,3 mm in length and from fresh to partially decomposed material and inorganic particles) depending on their availability. These capabilities allow ascidians in Potter Cove to survive periods with low primary production and high sedimentation. Horizontal transport (macroalgal detritus), sedimentation (fecal pellets and phytoplankton) and bottom resuspension (benthic microalgae and other particles settled on the bottom) are important processes which supply these particles to benthic filter feeders.