Details zur Publikation

Kategorie Textpublikation
Referenztyp Zeitschriften
DOI 10.1016/j.watres.2018.06.005
Titel (primär) Anoxic nitrogen cycling in a hydrocarbon and ammonium contaminated aquifer
Autor Wells, N.S.; Kappelmeyer, U. ORCID logo ; Knöller, K.
Quelle Water Research
Erscheinungsjahr 2018
Department UBT; CATHYD
Band/Volume 142
Seite von 373
Seite bis 382
Sprache englisch
Keywords Contaminated groundwater; Stable isotopes; Nitrite; Chemolithotrophic N cycling; Biodegradation; Nitrate dual isotopes
Abstract Nitrogen fate and transport through contaminated groundwater systems, where N is both ubiquitous and commonly limits pollutant attenuation, must be re-evaluated given evidence for new potential microbial N pathways. We addressed this by measuring the isotopic composition of dissolved inorganic N (DIN = NH4+, NO2, and NO3) and N functional gene abundances (amoA, nirK, nirS, hszA) from 20 to 38 wells across an NH4+, hydrocarbon, and SO42− contaminated aquifer. In-situ N attenuation was confirmed on three sampling dates (0, +6, +12 months) by the decreased [DIN] (4300 - 40 μM) and increased δ15N-DIN (5‰–33‰) over the flow path. However, the assumption of negligible N attenuation within the plume was complicated by the presence of alternative electron acceptors (SO42−, Fe3+), both oxidizing and reducing functional genes, and N oxides within this anoxic zone. Active plume N cycling was corroborated using an NO2 dual isotope based model, which found the fastest (∼10 day) NO2 turnover within the N and electron donor rich central plume. Findings suggest that N cycling is not always O2 limited within chemically complex contaminated aquifers, though this cycling may recycle the N species rather than attenuate N.
dauerhafte UFZ-Verlinkung
Wells, N.S., Kappelmeyer, U., Knöller, K. (2018):
Anoxic nitrogen cycling in a hydrocarbon and ammonium contaminated aquifer
Water Res. 142 , 373 - 382 10.1016/j.watres.2018.06.005