Publication Details

Reference Category Journals
DOI / URL link
Document Shareable Link
Title (Primary) Tracing aquatic priming effect during microbial decomposition of terrestrial dissolved organic carbon in chemostat experiments
Author Morling, K.; Raeke, J.; Kamjunke, N.; Reemtsma, T.; Tittel, J.;
Journal Microbial Ecology
Year 2017
Department SEEFO; FLOEK; ANA;
Volume 74
Issue 3
Language englisch;
POF III (all) T31;
Supplements https://static-content.springer.com/esm/art%3A10.1007%2Fs00248-017-0976-0/MediaObjects/248_2017_976_MOESM1_ESM.docx
Keywords Radiocarbon, 14C; Ultra-high-resolution mass spectrometry; FT-ICR MS, DOM quality
UFZ wide themes RU2;
Abstract Microbial decomposition of terrestrial carbon may be enhanced by the addition of easily decomposable compounds, a phenomenon referred to as priming effect. We investigated the microbial decomposition of terrestrial dissolved organic carbon (DOC) in one-stage and two-stage flow-through cultures (chemostats) in the absence and presence of growing phytoplankton as phytoplankton-derived organic matter might facilitate the mineralization of more refractory terrestrial compounds. Peat water and soil leachate were used as terrestrial substrates, and only slight DOC decomposition was observed in the absence of phytoplankton for both substrates. A priming effect was revealed via 14C data. Priming was more pronounced for the peat water substrate than for the soil leachate. The total DOC concentrations increased for both substrates in the presence of phytoplankton due to exudation and cell lysis. Samples from the soil leachate experiments were analyzed using ultra-high-resolution mass spectrometry (FT-ICR MS). Predominantly, the same saturated, aliphatic molecules with H/C ratios >1.5 were completely decomposed in the absence and in the presence of phytoplankton. The decomposition of more stable molecules differed in their intensity. Oxidized and unsaturated molecules with H/C ratios <1.0 and O/C ratios >0.4 were more strongly decomposed in phytoplankton presence (i.e., under priming). We conclude that an aquatic priming effect is not easily detectable via net concentration changes alone, and that qualitative investigations of the DOC processed by bacterial decomposition are necessary to detect aquatic priming.
ID 18632
Persistent UFZ Identifier http://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=18632
Morling, K., Raeke, J., Kamjunke, N., Reemtsma, T., Tittel, J. (2017):
Tracing aquatic priming effect during microbial decomposition of terrestrial dissolved organic carbon in chemostat experiments
Microb. Ecol. 74 (3), 534 - 549