caa a22 4500 605516774 CHVBK 20210128100716.0 cr unu---uuuuu 210128e20150101xx s 000 0 eng 10.1007/s10533-014-0029-4 doi (NATIONALLICENCE)springer-10.1007/s10533-014-0029-4 Origins and bioavailability of dissolved organic matter in groundwater [Elektronische Daten] [Yuan Shen, Francis Chapelle, Eric Strom, Ronald Benner] Dissolved organic matter (DOM) in groundwater influences water quality and fuels microbial metabolism, but its origins, bioavailability and chemical composition are poorly understood. The origins and concentrations of dissolved organic carbon (DOC) and bioavailable DOM were monitored during a long-term (2-year) study of groundwater in a fractured-rock aquifer in the Carolina slate belt. Surface precipitation was significantly correlated with groundwater concentrations of DOC, bioavailable DOM and chromophoric DOM, indicating strong hydrological connections between surface and ground waters. The physicochemical and biological processes shaping the concentrations and compositions of DOM during its passage through the soil column to the saturated zone are conceptualized in the regional chromatography model. The model provides a framework for linking hydrology with the processes affecting the transformation, remineralization and microbial production of DOM during passage through the soil column. Lignin-derived phenols were relatively depleted in groundwater DOM indicating substantial removal in the unsaturated zone, and optical properties of chromophoric DOM indicated lower molecular weight DOM in groundwater relative to surface water. The prevalence of glycine, γ-aminobutyric acid, and d-enantiomers of amino acids indicated the DOM was highly diagenetically altered. Bioassay experiments were used to establish DOC-normalized yields of amino acids as molecular indicators of DOM bioavailability in groundwater. A relatively small fraction (8±4%) of DOC in groundwater was bioavailable. The relatively high yields of specific d-enantiomers of amino acids indicated a substantial fraction (15-34%) of groundwater DOC was of bacterial origin. The Author(s), 2014 Groundwater nationallicence Dissolved organic matter nationallicence Amino acids nationallicence Lignin phenols nationallicence CDOM nationallicence Bioavailability nationallicence Regional chromatography model nationallicence Shen Yuan Marine Science Program, University of South Carolina, 29208, Columbia, SC, USA aut Chapelle Francis U.S. Geological Survey, South Carolina Water Science Center, 29210, Columbia, SC, USA aut Strom Eric U.S. Geological Survey, South Carolina Water Science Center, 29210, Columbia, SC, USA aut Benner Ronald Marine Science Program, University of South Carolina, 29208, Columbia, SC, USA aut Biogeochemistry Springer International Publishing 122/1(2015-01-01), 61-78 0168-2563 122:1<61 2015 122 10533 https://doi.org/10.1007/s10533-014-0029-4 text/html Onlinezugriff via DOI BK010053 XK010053 XK010000 Metadata rights reserved Springer special CC-BY-NC licence nationallicence 1 research-article jats NATIONALLICENCE NATIONALLICENCE NL-springer NATIONALLICENCE 856 40 https://doi.org/10.1007/s10533-014-0029-4 text/html Onlinezugriff via DOI NATIONALLICENCE 700 1- Shen Yuan Marine Science Program, University of South Carolina, 29208, Columbia, SC, USA aut NATIONALLICENCE 700 1- Chapelle Francis U.S. Geological Survey, South Carolina Water Science Center, 29210, Columbia, SC, USA aut NATIONALLICENCE 700 1- Strom Eric U.S. Geological Survey, South Carolina Water Science Center, 29210, Columbia, SC, USA aut NATIONALLICENCE 700 1- Benner Ronald Marine Science Program, University of South Carolina, 29208, Columbia, SC, USA aut NATIONALLICENCE 773 0- Biogeochemistry Springer International Publishing 122/1(2015-01-01), 61-78 0168-2563 122:1<61 2015 122 10533