Publication Details

Category Text Publication
Reference Category Journals
DOI 10.3390/w12020331
Licence creative commons licence
Title (Primary) Photochemically induced changes of dissolved organic matter in a humic‐rich and forested stream
Author Wilske, C.; Herzsprung, P.; Lechtenfeld, O.J. ORCID logo ; Kamjunke, N.; von Tümpling, W. ORCID logo
Source Titel Water
Year 2020
Department SEEFO; FLOEK; ANA
Volume 12
Page From art. 331
Language englisch
Keywords photodegradation; DOC; SUVA254; 2D fluorescence; HIX; FT‐ICR MS; PARAFAC; light‐dark
UFZ wide themes ProVIS;
Abstract Photochemical processing is an important way to transform terrestrial dissolved organic matter (DOM) but was rarely investigated by ultra‐high resolution mass spectrometry. We performed an irradiation experiment with water from a shaded forest stream flowing into a lit reservoir. Bacterial activity explained only 1% of dissolved organic carbon (DOC) decline in a combined bacterial and photodegradation approach. Photodegradation decreased the DOC concentration by 30%, the specific ultraviolet (UV) absorption by 40%–50%, and fluorescence intensity by 80% during six days. The humification index (HIX) decreased whereas the fluorescence index (FI) did not change. Two humic‐like components identified by parallel factor analysis (PARAFAC) of excitation–emission matrices followed the decrease of fluorescent DOM. Changes
of relative peak intensities of Fourier transform‐ion cyclotron resonance mass spectroscopy (FT‐ICR MS) elemental formula components as a function of cumulated radiation were evaluated both by Spearman’s rank correlation and linear regression. The FT‐ICR MS intensity changes indicate that high aromatic material was photochemically converted into smaller non‐fluorescent molecules or degraded by the release of CO2. This study shows the molecular change of terrestrial DOM before the preparation of drinking water from reservoirs.
Persistent UFZ Identifier
Wilske, C., Herzsprung, P., Lechtenfeld, O.J., Kamjunke, N., von Tümpling, W. (2020):
Photochemically induced changes of dissolved organic matter in a humic‐rich and forested stream
Water 12 , art. 331 10.3390/w12020331