Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1016/j.scitotenv.2021.150049
Lizenz creative commons licence
Titel (primär) Effects of DOC addition from different sources on phytoplankton community in a temperate eutrophic lake: An experimental study exploring lake compartments
Autor Fonseca, B.M.; Levi, E.E.; Westphalen Jensen, L.; Graeber, D.; Søndergaard, M.; Lauridsen, T.L.; Jeppesen, E.; Davidson, T.A.
Quelle Science of the Total Environment
Erscheinungsjahr 2022
Department ASAM
Band/Volume 803
Seite von art. 150049
Sprache englisch
Topic T5 Future Landscapes
Supplements https://ars.els-cdn.com/content/image/1-s2.0-S004896972105124X-mmc1.docx
Keywords Low-level brownification; Mesocosm experiment; Leaf leachate; Primary production; Pulse disturbance
Abstract A mesocosm experiment was conducted in a temperate eutrophic lake with the hypotheses: 1) the addition of a labile form of DOC would trigger a more pronounced response in phytoplankton biomass and composition compared with a non-labile form; 2) DOC addition would increase phytoplankton biomass by co-inserting organic nutrients for phytoplankton growth; 3) DOC addition would change phytoplankton composition, in particular towards mixotrophic taxa due to higher DOC availability; and that 4) there would be differences in phytoplankton responses to DOC addition, depending on whether sediment was included or not. We used two types of mesocosms: pelagic mesocosms with closed bottom, and benthic mesocosms open to the sediment. The experiment ran for 29 days in total. The DOC addition occurred once, at Day 1. Besides the control, there were two treatments: HuminFeed® (non-labile DOC) at a concentration of 2 mg L−1, and a combination of 2 mg L−1 HuminFeed® and 2 mg L−1 DOC from alder leaf leachate (labile). Responses were detected only in the treatment with alder leaf extract. Ecosystem processes responded immediately to DOC addition, with the fall in dissolved oxygen and pH indicating an increase in respiration, relative to primary production (Day 2). In contrast, there was a delay of a few days in structural responses in the phytoplankton community (Day 6). Phytoplankton biomass increased after DOC addition, probably boosted by the phosphorus released from alder leaf extract. Changes in phytoplankton composition towards mixotrophic taxa were not as strong as changes in biomass, and happened only in the pelagic mesocosms. With the DOC addition, diatoms prevailed in benthic mesocosms, while the contribution of colonial buoyant cyanobacteria increased in the pelagic ones. This study points towards the necessity to look in greater detail at specific responses of phytoplankton to DOC concentration increases considering lake-habitat and sediment influence.
dauerhafte UFZ-Verlinkung https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=25105
Fonseca, B.M., Levi, E.E., Westphalen Jensen, L., Graeber, D., Søndergaard, M., Lauridsen, T.L., Jeppesen, E., Davidson, T.A. (2022):
Effects of DOC addition from different sources on phytoplankton community in a temperate eutrophic lake: An experimental study exploring lake compartments
Sci. Total Environ. 803 , art. 150049 10.1016/j.scitotenv.2021.150049