|Physical-biological coupling in southern Lake Michigan: influence of episodic sediment resuspension on phytoplankton|
Millie, D.F.; Fahnenstiel, G.L.; Lohrenz, S.E.; Carrick, H.J.; Johengen, T.H.; Schofield, O.M.E. (2003). Physical-biological coupling in southern Lake Michigan: influence of episodic sediment resuspension on phytoplankton. Aquat. Ecol. 37(4): 393-408
In: Aquatic Ecology. Springer: Dordrecht; London; Boston. ISSN 1386-2588, more
Diatoms; Growth; Photosynthesis; Phytoplankton; Resuspension; Suspended particulate matter; USA, Michigan, Michigan L. [Marine Regions]; Fresh water
|Authors|| || Top |
- Millie, D.F., correspondent
- Fahnenstiel, G.L.
- Lohrenz, S.E.
- Carrick, H.J.
- Johengen, T.H.
- Schofield, O.M.E.
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.