Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1016/j.watres.2020.115701
Volltext Akzeptiertes Manuskript
Titel (primär) The formation of a metalimnetic oxygen minimum exemplifies how ecosystem dynamics shape biogeochemical processes: A modelling study
Autor Mi, C.; Shatwell, T.; Ma, J.; Wentzky, V.C.; Boehrer, B.; Xu, Y.; Rinke, K.
Quelle Water Research
Erscheinungsjahr 2020
Department SEEFO
Band/Volume 175
Seite von art. 115701
Sprache englisch
Keywords Rappbode reservoir; CE-QUAL-W2; Planktothrix rubescens; Metalimnion; Oxygen consumption; Benthic processes
Abstract Metalimnetic oxygen minima are observed in many lakes and reservoirs, but the mechanisms behind this phenomena are not well understood. Thus, we simulated the metalimnetic oxygen minimum (MOM) in the Rappbode Reservoir with a well-established two-dimensional water quality model (CE-QUAL-W2) to systematically quantify the chain of events leading to its formation. We used high-resolution measured data to calibrate the model, which accurately reproduced the physical (e.g. water level and water temperature), biogeochemical (e.g. nutrient and oxygen dynamics) and ecological (e.g. algal community dynamics) features of the reservoir, particularly the spatial and temporal extent of the MOM. The results indicated that around 60% of the total oxygen consumption rate in the MOM layer originated from benthic processes whereas the remainder originated from pelagic processes. The occurrence of the cyanobacterium Planktothrix rubescens in the metalimnion delayed and slightly weakened the MOM through photosynthesis, although its decaying biomass ultimately induced the MOM. Our research also confirmed the decisive role of water temperature in the formation of the MOM since the water temperatures, and thus benthic and pelagic oxygen consumption rates, were higher in the metalimnion than in the hypolimnion. Our model is not only providing novel conclusions about the drivers of MOM development and their quantitative contributions, it is also a new tool for understanding and predicting ecological and biogeochemical water quality dynamics.
dauerhafte UFZ-Verlinkung https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=23064
Mi, C., Shatwell, T., Ma, J., Wentzky, V.C., Boehrer, B., Xu, Y., Rinke, K. (2020):
The formation of a metalimnetic oxygen minimum exemplifies how ecosystem dynamics shape biogeochemical processes: A modelling study
Water Res. 175 , art. 115701 10.1016/j.watres.2020.115701