Department of Biology

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Mark Lever

Effects of eutrophication on sedimentary organic carbon cycling in five temperate lakes

Research output: Contribution to journal/Conference contribution in journal/Contribution to newspaperJournal articleResearchpeer-review


  • Annika Fiskal, Swiss Federal Institute of Technology Zurich
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  • Longhui Deng, Swiss Federal Institute of Technology Zurich
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  • Anja Michel, Swiss Federal Institute of Technology Zurich
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  • Philip Eickenbusch, Swiss Federal Institute of Technology Zurich
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  • Xingguo Han, Swiss Federal Institute of Technology Zurich
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  • Lorenzo Lagostina, Swiss Federal Institute of Technology Zurich
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  • Rong Zhu, Swiss Federal Institute of Technology Zurich
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  • Michael Sander, Swiss Federal Institute of Technology Zurich
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  • Martin H. Schroth, Swiss Federal Institute of Technology Zurich
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  • Stefano M. Bernasconi, Swiss Federal Institute of Technology Zurich
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  • Nathalie Dubois, Swiss Federal Institute of Aquatic Science and Technology, Swiss Federal Institute of Technology Zurich
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  • Mark A. Lever

Even though human-induced eutrophication has severely impacted temperate lake ecosystems over the last centuries, the effects on total organic carbon (TOC) burial and mineralization are not well understood. We study these effects based on sedimentary records from the last 180 years in five Swiss lakes that differ in trophic state. We compare changes in TOC content and modeled TOC accumulation rates through time to historical data on algae blooms, water column anoxia, wastewater treatment, artificial lake ventilation, and water column phosphorus (P) concentrations. We furthermore investigate the effects of eutrophication on rates of microbial TOC mineralization and vertical distributions of microbial respiration reactions in sediments. Our results indicate that the history of eutrophication is well recorded in the sedimentary record. Overall, eutrophic lakes have higher TOC burial and accumulation rates, and subsurface peaks in TOC coincide with past periods of elevated P concentrations in lake water. Sediments of eutrophic lakes, moreover, have higher rates of total respiration and higher contributions of methanogenesis to total respiration. However, we found strong overlaps in the distributions of respiration reactions involving different electron acceptors in all lakes regardless of lake trophic state. Moreover, even though water column P concentrations have been reduced by ∼ 50 %-90 % since the period of peak eutrophication in the 1970s, TOC burial and accumulation rates have only decreased significantly, by ∼ 20 % and 25 %, in two of the five lakes. Hereby there is no clear relationship between the magnitude of the P concentration decrease and the change in TOC burial and accumulation rate. Instead, data from one eutrophic lake suggest that artificial ventilation, which has been used to prevent water column anoxia in this lake for 35 years, may help sustain high rates of TOC burial and accumulation in sediments despite water column P concentrations being strongly reduced. Our study provides novel insights into the influence of human activities in lakes and lake watersheds on lake sediments as carbon sinks and habitats for diverse microbial respiration processes.

Original languageEnglish
Pages (from-to)3725-3746
Number of pages22
Publication statusPublished - 30 Sep 2019
Externally publishedYes

Bibliographical note

Funding Information:
Financial support. This research has been supported by the Swiss

Publisher Copyright:
© 2019 Author(s).

Copyright 2019 Elsevier B.V., All rights reserved.

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