loading page

Seasonal phytoplankton and geochemical shifts in the subsurface chlorophyll maximum layer of a dimictic ferruginous lake
  • +5
  • Elizabeth Swanner,
  • Marina Wuestner,
  • Tania Leung,
  • Juergen Pust,
  • Micah Fatka,
  • Nick Lambrecht,
  • Hannah Chmiel,
  • Harald Strauss
Elizabeth Swanner
Iowa State University

Corresponding Author:[email protected]

Author Profile
Marina Wuestner
University of Tubingen Faculty of Science
Author Profile
Tania Leung
Iowa State University
Author Profile
Juergen Pust
Landschaftsverband Westfalen-Lippe
Author Profile
Micah Fatka
Iowa State University
Author Profile
Nick Lambrecht
Iowa State University
Author Profile
Hannah Chmiel
École Polytechnique Fédérale de Lausanne
Author Profile
Harald Strauss
University of Munster
Author Profile


Subsurface chlorophyll maxima layers (SCML) are ubiquitous features of stratified aquatic systems. Availability of the micronutrient iron is known to influence marine SCML, but iron has not been explored in detail as a factor in the development of freshwater SCML. This study investigates the relationship between dissolved iron and the SCML within the dimictic, ferruginous lake Grosses Heiliges Meer in northern Germany. The occurrence of the SCML under non-ferruginous conditions in the spring and ferruginous conditions in the fall are context to explore temporal changes in the phytoplankton community and indicators of primary productivity. Results indicate that despite more abundant chlorophyll in the spring, the SCML sits below a likely primary productivity maximum within the epilimnion, inferred based on co-located dissolved oxygen, δ13CDIC, and pH maxima. The peak amount of chlorophyll in the SCML is lower in the fall than in the spring, but in the fall the SCML is co-located with elevated dissolved iron concentrations and a local δ13CDIC maximum. Cyanobacteria and Chlorophyta have elevated abundances within the SCML in the fall. Further investigation of the relationship of iron to primary productivity within ferruginous SCML may help to understand the environmental controls on primary productivity in past ferruginous oceans.
17 Mar 2022Submitted to MicrobiologyOpen
18 Mar 2022Submission Checks Completed
18 Mar 2022Assigned to Editor
25 Mar 2022Reviewer(s) Assigned
07 Apr 2022Review(s) Completed, Editorial Evaluation Pending
12 Apr 2022Editorial Decision: Revise Minor
14 Apr 20221st Revision Received
19 Apr 2022Submission Checks Completed
19 Apr 2022Assigned to Editor
20 Apr 2022Review(s) Completed, Editorial Evaluation Pending
27 Apr 2022Editorial Decision: Accept