Physical-Biological Coupling in Southern Lake Michigan: Influence of Episodic Sediment Resuspension on Phytoplankton
Document Type
Article
Publication Date
10-1-2003
Department
Marine Science
Abstract
The influence of episodic, sediment resuspension on phytoplankton abundance/volume and composition, the photosynthetic maximum rate (PBmax) and efficiency (αB), and chlorophyll-specific growth (μChl) was evaluated during the spring isothermal period in southern Lake Michigan (Laurentian Great Lakes, USA). Resuspension altered the nutrient and light climate of nearshore waters; light attenuation (Kd) and phosphorus concentrations corresponded (p ≤ 0.0001 and p ≤ 0.001, respectively) with concentrations of suspended particulate matter (SPM). Phytoplankton cell volume and diatom cell abundance and volume were not associated with SPM concentrations (p > 0.05). Diatom composition displayed spatial dissimilarities corresponding with resuspension (p ≤ 0.001); small centric diatoms exhibiting meroplanktonic life histories and pennate diatoms considered benthic in origin were most abundant within SPM-impacted, nearshore waters whereas taxa typically comprising assemblages in optically-clear, offshore waters and the basin-wide, spring bloom were not. Values of PBmax and αB corresponded (p ≤ 0.0001) with both Kd coefficients and SPM concentrations, potentially reflecting increased light harvesting/utilization within impacted assemblages. However, integral production was inversely associated with Kd coefficients and SPM concentrations (p < 0.0001) and photosynthesis was light-limited (or nearly so) for most assemblages. Although μChl values corresponded with Kd coefficients (p ≤ 0.05), values were quite low (x ± S.E., 0.10 ± 0.004 d-1) throughout the study. Most likely, distinct rate processes between SPM- and non-impacted assemblages reflected short-term compositional (and corresponding physiological) variations due to infusion of meroplankton and/or tributary-derived phytoplankton. Overall, resuspension appears to have little, if any, long-term impact upon the structure and function of the lake’s phytoplankton.
Publication Title
Aquatic Ecology
Volume
37
Issue
4
First Page
393
Last Page
408
Recommended Citation
Millie, D. F.,
Fahnenstiel, G. L.,
Lohrenz, S. E.,
Carrick, H. J.,
Johengen, T. H.,
Schofield, O. M.
(2003). Physical-Biological Coupling in Southern Lake Michigan: Influence of Episodic Sediment Resuspension on Phytoplankton. Aquatic Ecology, 37(4), 393-408.
Available at: https://aquila.usm.edu/fac_pubs/3162