Oxygen depletion in stratified lake waters

This project is a collaboration between APHYS and the Eawag department: Surface Waters – Research and Management. The focus of this research is to understand the intensity and temporal dynamics of oxygen depletion in the hypolimnion of lakes, as a response to the in-situ biogenic productivity of organic matter.

The goal of this interdisciplinary research study is to:

quantify the areal hypolimnetic mineralization rate (AHM) as a function the lake-topographies and nutrient supply (level of trophy)
characterise the reaction of AHM during the current oligotrophication
identify the locations of AHM in the hypolimnion
relate AHM and sediment oxygen uptake with the organic matter content in the sediment

Figure shows two oxygen microprofiles across the water–sediment–interface and the DBL thickness in 45 m (blue) and 133 m depth (red) in Lake Geneva.

Schwefel, R., Gaudard, A., Wüest, A., and Bouffard, D. ( 2016),  Effects of climate change on deepwater oxygen and winter mixing in a deep lake (Lake Geneva): Comparing observational findings and modelingWater Resour. Res.,  52,  8811– 8826, doi:10.1002/2016WR019194.

Schwefel, R., Steinsberger, T., Bouffard, D., Bryant, L.D., Müller, B. and Wüest, A. (2018), Using small‐scale measurements to estimate hypolimnetic oxygen depletion in a deep lake. Limnol. Oceanogr., 63: S54-S67. doi:10.1002/lno.10723

Schwefel, R.,  Hondzo, M.,  Wüest, A., and  Bouffard, D. ( 2017),  Scaling oxygen microprofiles at the sediment interface of deep stratified watersGeophys. Res. Lett,  44,  1340– 1349, doi:10.1002/2016GL072079.

Müller, B., T. Steinsberger, R. Schwefel, R. Gächter, M. Sturm, A. Wüest (2019). Oxygen consumption in seasonally stratified lakes decreases only below a marginal phosphorus threshold. Scientific Reports 9: 18054. https://doi.org/10.1038/s41598-019-54486-3

Steinsberger, T., M. Schmid, A. Wüest, R. Schwefel, B. Wehrli, B. Müller (2017). Organic carbon mass accumulation rate regulates the flux of reduced substances from the sediments of deep lakes. Biogeosciences 14(13), 3275-3285. https://doi.org/10.5194/bg-14-3275-2017

Kiefer Steinsberger Wüest Müller Sauerstoffzehrung AG 2020