Publication Details

Category Text Publication
Reference Category Journals
DOI 10.1021/es2026196
Title (Primary) A bench-scale constructed wetland as a model to characterize benzene biodegradation processes in freshwater wetlands
Author Rakoczy, J.; Remy, B.; Vogt, C.; Richnow, H.H.
Source Titel Environmental Science & Technology
Year 2011
Department ISOBIO
Volume 45
Issue 23
Page From 10036
Page To 10044
Language englisch
Abstract
In wetlands, a variety of biotic and abiotic processes can contribute to the removal of organic substances. Here, we used compound-specific isotope analysis (CSIA), hydrogeochemical parameters and detection of functional genes to characterize in situ biodegradation of benzene in a model constructed wetland over a period of 370 days. Despite low dissolved oxygen concentrations (<30 μM), the oxidation of ammonium to nitrate and the complete oxidation of ferrous iron pointed to a dominance of aerobic processes, suggesting efficient oxygen transfer into the sediment zone by plants. As benzene removal became highly efficient after day 231 (>98% removal), we applied CSIA to study in situ benzene degradation by indigenous microbes. Combining carbon and hydrogen isotope signatures by two-dimensional stable isotope analysis revealed that benzene was degraded aerobically, mainly via the monohydroxylation pathway. This was additionally supported by the detection of the BTEX monooxygenase gene tmoA in sediment and root samples. Calculating the extent of biodegradation from the isotope signatures demonstrated that at least 85% of benzene was degraded by this pathway and thus, only a small fraction was removed abiotically. This study shows that model wetlands can contribute to an understanding of biodegradation processes in floodplains or natural wetland systems.
Persistent UFZ Identifier https://www.ufz.de/index.php?en=20939&ufzPublicationIdentifier=11736
Rakoczy, J., Remy, B., Vogt, C., Richnow, H.H. (2011):
A bench-scale constructed wetland as a model to characterize benzene biodegradation processes in freshwater wetlands
Environ. Sci. Technol. 45 (23), 10036 - 10044 10.1021/es2026196