Diel Changes in Phytoplankton Composition and Abundance in the Surface and Sub-Surface Strata from a Shallow Eutrophic Pond

• Published in: International review of hydrobiology. 2009-02, Vol.94 (1), p.29-39
• Main Authors: Wilk-Woźniak, Elżbieta, Marshall, Harold G.
• Format: Article
• Language: English
• Subjects: Animal and plant ecology; Animal, plant and microbial ecology; Bacillariophyceae; Biological and medical sciences; Cyanobacteria; diurnal study; Fresh water ecosystems; Fundamental and applied biological sciences. Psychology; General aspects; neuston; picoplankton; pond; Synecology
• ISSN: 1434-2944; 1522-2632
• DOI: 10.1002/iroh.200811112

Representative phytoplankton assemblages were identified in a eutrophic pond over a 24 hour period. One assemblage characterized species in the surface (neuston) layer and another consisted of algae from 2, 5, and 20 cm sub‐surface depths. The surface layer (0 cm) included a similar, but less diverse assemblage of species, and a lower abundance of cells per unit volume, than those at the lower depths. At each of the sub‐surface depths (2–20 cm), the major phytoplankton components initially followed similar patterns of abundance in reference to the time and depth of sample collections then later differed in their abundance levels. The dominant algae were chlorophytes, cryptophytes, diatoms, and cyanobacteria. Mean concentrations of total phytoplankton, over the 24 hours for the surface, were 3.3 × 103 cells ml–1, compared to 36.9 × 103 cells ml–1 for depths 2–20 cm. The autotrophic picoplankton abundance was recorded separately from the phytoplankton with mean concentrations of 472.9 × 103 cells ml–1 in the surface layer and 623.0 × 103 cells ml–1 for the three sub‐surface depths. Photos of representative species from these surface layers are presented. (© 2009 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)