Quality of Particulate Matter and Its Potential Sinking Rates in Pelagic Samples of Inshore and Bodden Waters of the Southern Baltic Sea

• Published in: International review of hydrobiology. 2000-01, Vol.85 (2-3), p.341-357
• Main Authors: Estrum-Yousef, Susen R., Feuerpfeil, Peter, Schubert, Hendrik, Schumann, Rhena
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Biological and medical sciences; Coastal oceanography, estuaries. Regional oceanography; Earth, ocean, space; Exact sciences and technology; External geophysics; Fundamental and applied biological sciences. Psychology; Marine; marine coastal waters; particulate organic matter; Physics of the oceans; Sea water ecosystems; settling flux; settling tubes; sinking velocity; Synecology
• ISSN: 1434-2944; 1522-2632
• DOI: 10.1002/(SICI)1522-2632(200004)85:2/3<341::AID-IROH341>3.0.CO;2-H

In situ measurements of vertical particle transport are strongly influenced by water currents and resuspension. For mass balances, especially for calculations of POM im‐ and export in certain areas, or for estimating the significance of aggregate formation in the context of organisms' removal from the euphotic zone, a potential sedimentation of organic particles preferably in combination with particle quality parameters influencing sinking velocity is needed. Sedimentation of POM can be measured by small scale laboratory experiments in settling tubes. We used different parameters that describe the quantity and quality of POM in combination with the SETCOL method. Sinking rates of POC from 3 different nearshore and inner coastal waters of the Southern Baltic Sea were low with 1–32 cm d–1, but comparable to rates obtained from several phytoplankton species, e.g. diatoms, which are important parts of POM and have a similar size range compared to the particles investigated in this study. We did not find any correlation between the sinking rate and the quantity or quality of particulate organic matter. Obviously, the differences in organic matter composition of particles smaller than 200 μm, investigated with this miniscale experimental method, did not affect the sinking rates considerably. Calculated from sinking rates and POC concentrations 19–1,430 mg C could sediment per squaremetre and day, if horizontal matter transfer and resuspension were ignored as it was done during the settling procedure. Concerning the application of the SETCOL method to plankton samples we must stress the importance of appropriate laboratory incubation conditions. Special attention has to be paid to an equal light climate and oxygen supply for the reference and settling vessels.