Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1016/j.watres.2017.01.066
Titel (primär) Linking the mobilization of dissolved organic matter in catchments and its removal in drinking water treatment to its molecular characteristics
Autor Raeke, J.; Lechtenfeld, O.J. ORCID logo ; Tittel, J.; Oosterwoud, M.R.; Bornmann, K.; Reemtsma, T.
Quelle Water Research
Erscheinungsjahr 2017
Department SEEFO; ANA; HDG
Band/Volume 113
Seite von 149
Seite bis 159
Sprache englisch
Keywords FTICR-MS; Radiocarbon; Mobilization; Flocculation; Drinking water treatment; Ultrahigh resolution mass spectrometry
UFZ Querschnittsthemen ProVIS; RU2;
Abstract Drinking water reservoirs in the Northern Hemisphere are largely affected by the decadal-long increase in riverine dissolved organic carbon (DOC) concentrations. The removal of DOC in drinking water treatment is costly and predictions are needed to link DOC removal efficiency to its mobilization in catchments, both of which are determined by the molecular composition. To study the effect of hydrological events and land use on the molecular characteristics of dissolved organic matter (DOM), 36 samples from three different catchment areas in the German low mountain ranges, with DOC concentrations ranging from 3 to 32 mg L−1, were examined. Additionally, nine pairs of samples from downstream drinking water reservoirs were analyzed before and after flocculation. The molecular composition and the age of DOM were analyzed using ultrahigh resolution Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) and radiocarbon (14C) analysis. At elevated discharge in a forested catchment comparatively younger, more oxygenated and unsaturated molecules of higher molecular weight were preferentially mobilized, likely linked to the reductive mobilization of iron. DOM with highly similar molecular characteristics (O/C ratio > 0.5, m/z > 500) could also be efficiently removed through flocculation in drinking water treatment. The proportion of DOM removed through flocculation ranged between 43% and 73% of DOC and was highest at elevated discharge. In catchment areas with a higher percentage of grassland and agriculture a higher proportion of DOM molecules containing sulfur and nitrogen was detected, which in turn could be less efficiently flocculated. Altogether, it was shown that DOM that is released during large hydrological events can be efficiently flocculated again, suggesting a reversal of similar chemical mechanisms in both processes. Since the occurrence of heavy rainfall events is predicted to increase in the future, event-driven mobilization of DOC may continue to challenge drinking water production.
dauerhafte UFZ-Verlinkung
Raeke, J., Lechtenfeld, O.J., Tittel, J., Oosterwoud, M.R., Bornmann, K., Reemtsma, T. (2017):
Linking the mobilization of dissolved organic matter in catchments and its removal in drinking water treatment to its molecular characteristics
Water Res. 113 , 149 - 159 10.1016/j.watres.2017.01.066