Hydrocarbons to carboxyl-rich alicyclic molecules: A continuum model to describe biodegradation of petroleum-derived dissolved organic matter in contaminated groundwater plumes
Links
- More information: Publisher Index Page (via DOI)
- Open Access Version: Publisher Index Page
- Download citation as: RIS | Dublin Core
Abstract
Relationships between dissolved organic matter (DOM) reactivity and chemical composition in a groundwater plume containing petroleum-derived DOM (DOMHC) were examined by quantitative and qualitative measurements to determine the source and chemical composition of the compounds that persist downgradient. Samples were collected from a transect down the core of the plume in the direction of groundwater flow. An exponential decrease in dissolved organic carbon concentration resulting from biodegradation along the transect correlated with a continuous shift in fluorescent DOMHC from shorter to longer wavelengths. Moreover, ultrahigh resolution mass spectrometry showed a shift from low molecular weight (MW) aliphatic, reduced compounds to high MW, unsaturated (alicyclic/aromatic), high oxygen compounds that are consistent with carboxyl-rich alicyclic molecules. The degree of condensed aromaticity increased downgradient, indicating that compounds with larger, conjugated aromatic core structures were less susceptible to biodegradation. Nuclear magnetic resonance spectroscopy showed a decrease in alkyl (particularly methyl) and an increase in aromatic/olefinic structural motifs. Collectively, data obtained from the combination of these complementary analytical techniques indicated that changes in the DOMHC composition of a groundwater plume are gradual, as relatively low molecular weight (MW), reduced, aliphatic compounds from the oil source were selectively degraded and high MW, alicyclic/aromatic, oxidized compounds persisted.
Study Area
| Publication type | Article |
|---|---|
| Publication Subtype | Journal Article |
| Title | Hydrocarbons to carboxyl-rich alicyclic molecules: A continuum model to describe biodegradation of petroleum-derived dissolved organic matter in contaminated groundwater plumes |
| Series title | Journal of Hazardous Materials |
| DOI | 10.1016/j.jhazmat.2020.123998 |
| Volume | 402 |
| Year Published | 2021 |
| Language | English |
| Publisher | Elsevier |
| Contributing office(s) | WMA - Earth System Processes Division |
| Description | 123998, 16 p. |
| Country | United States |
| State | Minnesota |
| City | Bemidji |
| Google Analytic Metrics | Metrics page |