Impact of solar radiation on the biological removal of dimethylsulfoniopropionate and dimethylsulfide in marine surface waters

Author(s)
Doris Slezak, Albert Brugger, Gerhard J. Herndl
Abstract

The effect of natural surface solar radiation on the biological removal of dimethylsulfoniopropionate (DMSP) and dimethylsulfide (DMS) was determined and compared to the photochemical removal of DMSP and DMS. Natural bacterial assemblages (0.8 μm filtered seawater) from the northern Adriatic Sea and the coastal North Sea were exposed to surface solar radiation and incubated in the dark; the DMSP and DMS concentrations were measured concurrently. Photochemical removal rates were determined in 0.2 μm filtered seawater. Biological removal of DMSP in the light was 62 ± 14% lower than the biological removal rate obtained in the dark. High spatial and temporal variability in the biological removal rates was observed for the dark treatments, as well as for its sensivity to solar radiation, with rates for light treatments varying from 29 to 81% of those in the dark. The DMSP concentration above which no further increase of the biological DMSP removal rate was observed was substantially lower in the light treatments (∼30 nM) than in the dark treatments (>80 nM). UV-B radiation only accounted for a minor inhibitory effect (∼15% of total inhibition), whereas UV-A and PAR (photosynthetically active radiation) both contributed ∼42% of total inhibition. Biological DMS removal under solar radiation was only ∼40 ± 14% of the biological DMS removal in the dark. Under surface solar radiation, photochemical removal was always higher than the dark biological removal. Our results indicate therefore, that the DMSP and DMS dynamics in the oceanic surface waters are severely influenced by solar radiation due to the partial inhibition of the microbial consortia responsible for DMSP and DMS turnover.

Organisation(s)
External organisation(s)
Royal Netherlands Institute for Sea Research
Journal
Aquatic Microbial Ecology
Volume
25
Pages
87-97
No. of pages
11
ISSN
0948-3055
DOI
https://doi.org/10.3354/ame025087
Publication date
08-2001
Peer reviewed
Yes
Austrian Fields of Science 2012
106022 Microbiology
Keywords
ASJC Scopus subject areas
Ecology, Evolution, Behavior and Systematics, Aquatic Science
Sustainable Development Goals
SDG 14 - Life Below Water
Portal url
https://ucrisportal.univie.ac.at/en/publications/bdf64fdb-869d-4221-ae96-da8b560a8da2