Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1016/j.scitotenv.2017.12.285
Document author version
Title (Primary) Going with the flow: Planktonic processing of dissolved organic carbon in streams
Author Graeber, D.; Rosenstand Poulsen, J.; Heinz, M.; Rasmussen, J.J.; Zak, D.; Gücker, B.; Kronvang, B.; Kamjunke, N.
Source Titel Science of the Total Environment
Year 2018
Department ASAM; FLOEK
Volume 625
Page From 519
Page To 530
Language englisch
Keywords Terrestrial DOC; Agricultural catchment; Flood pulse; Hydrology; Bacteria
UFZ wide themes RU2;
Abstract A large part of the organic carbon in streams is transported by pulses of terrestrial dissolved organic carbon (tDOC) during hydrological events, which is more pronounced in agricultural catchments due to their hydrological flashiness. The majority of the literature considers stationary benthic biofilms and hyporheic biofilms to dominate uptake and processing of tDOC. Here, we argue for expanding this viewpoint to planktonic bacteria, which are transported downstream together with tDOC pulses, and thus perceive them as a less variable resource relative to stationary benthic bacteria. We show that pulse DOC can contribute significantly to the annual DOC export of streams and that planktonic bacteria take up considerable labile tDOC from such pulses in a short time frame, with the DOC uptake being as high as that of benthic biofilm bacteria. Furthermore, we show that planktonic bacteria efficiently take up labile tDOC which strongly increases planktonic bacterial production and abundance. We found that the response of planktonic bacteria to tDOC pulses was stronger in smaller streams than in larger streams, which may be related to bacterial metacommunity dynamics. Furthermore, the response of planktonic bacterial abundance was influenced by soluble reactive phosphorus concentration, pointing to phosphorus limitation. Our data suggest that planktonic bacteria can efficiently utilize tDOC pulses and likely determine tDOC fate during downstream transport, influencing aquatic food webs and related biochemical cycles.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=19780
Graeber, D., Rosenstand Poulsen, J., Heinz, M., Rasmussen, J.J., Zak, D., Gücker, B., Kronvang, B., Kamjunke, N. (2018):
Going with the flow: Planktonic processing of dissolved organic carbon in streams
Sci. Total Environ. 625 , 519 - 530 10.1016/j.scitotenv.2017.12.285