Effects of Planktonic Copepods on Transparent Exopolymeric Particles (TEP) Abundance and Size Spectra

Diatoms exude considerable quantities of polymers, mainly polysaccharides, that play an important role in the process of sestonic particle aggregation in the sea. We investigated the impact of copepods on transparent exopolymeric particles (TEP) generated by the diatom Thalassiosira weissflogii. Gra...

Full description

Saved in:
Bibliographic Details
Published in:Journal of plankton research 2001-05, Vol.23 (5), p.515-525
Main Authors: Prieto, Laura, Sommer, Frank, Stibor, Herwig, Koeve, Wolgang
Format: Article
Language:English
Subjects:
Abundance
Aggregation
Algae
Animal and plant ecology
Animal, plant and microbial ecology
Aquatic crustaceans
Bacillariophyceae
Biological and medical sciences
Copepoda
Diatoms
Exudates
Fundamental and applied biological sciences. Psychology
Incubation
Marine
Particle settling
Polymers
Polysaccharides
Radioactivity
Sea water ecosystems
Size distribution
Spectra
Synecology
Thalassiosira weissflogii
Uptake
Water column
Citations: Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Diatoms exude considerable quantities of polymers, mainly polysaccharides, that play an important role in the process of sestonic particle aggregation in the sea. We investigated the impact of copepods on transparent exopolymeric particles (TEP) generated by the diatom Thalassiosira weissflogii. Grazing experiments with 14C-labelled algae exudates demonstrated that copepods typical of the Baltic Sea were not actively filtering TEP. Control experiments showed that ‘uptake’ of radioactivity could be ascribed to passive uptake, such as adsorption of radioactively-labelled particles to the body surface. Furthermore, we tested the effect of copepods on TEP size spectra. The abundance and size distribution of TEP (from 1.4 to 180 μm of Equivalent Spherical Diameter) were analysed in a 4 h incubation experiment. In the presence of copepods, the proportion of larger TEP was higher. An increase in total volume of TEP in jars containing copepods (~2 × 107 μm ml–1) compared with control jars without copepods (~0.5 × 107 μm3 ml–1) was also observed. The process of aggregation of TEP demonstrated in this work, whereby copepods increase downward particle flux without consuming carbon, can have far-reaching consequences for carbon fluxes along the water column and for copepods feeding dynamics.
ISSN:0142-7873
1464-3774
1464-3774
DOI:10.1093/plankt/23.5.515