Hydrogeochemical and microbiological effects of simulated recharge and drying within a 2D meso-scale aquifer

Copyright © 2019 Elsevier Ltd. All rights reserved..

Oscillating cycles of dewatering (termed drying) and rewetting during managed aquifer recharge (MAR) are used to maintain infiltration rates and could also exert an influence on subsurface microbial structure and respiratory processes. Despite this practice, little knowledge is available about changes to microbial community structure and trace organic chemical biodegradation potential in MAR systems under these conditions. A biologically active two-dimensional (2D) synthetic MAR system equipped with automated sensors (temperature, water pressure, conductivity, soil moisture, oxidation-reduction potential) and embedded water and soil sampling ports was used to test and model these important subsurface processes at the meso-scale. The fate and transport of the antiepileptic drug carbamazepine, the antibiotics sulfamethoxazole and trimethoprim, and the flame retardant tris (2-chloroethyl) phosphate were simulated using the finite element analysis model, FEFLOW. All of these compounds exhibit moderate to poor biodegradability in MAR systems. Within the operational MAR scenario tested, three episodic drying cycles spanning between 18 and 24 days were conducted over a period of 184 days. Notably, cessation of flow and partial dewatering of the 2D synthetic aquifer during dry cycles caused no measurable decrease in soil moisture content beyond the near-surface layer. The episodic flow introduction and dewatering cycles in turn had little impact on overall trace organic chemical biotransformation behavior and soil microbial community structure. However, spatial differences in oxidation-reduction potential and soil moisture were both identified as significant environmental predictors for microbial community structure in the 2D synthetic aquifer.

Medienart:

E-Artikel

Erscheinungsjahr:

2020

Erschienen:

2020

Enthalten in:

Zur Gesamtaufnahme - volume:241

Enthalten in:

Chemosphere - 241(2020) vom: 22. Feb., Seite 125116

Sprache:

Englisch

Beteiligte Personen:

Regnery, Julia [VerfasserIn]
Li, Dong [VerfasserIn]
Lee, Jonghyun [VerfasserIn]
Smits, Kathleen M [VerfasserIn]
Sharp, Jonathan O [VerfasserIn]

Links:

Volltext

Themen:

Contaminant transport
Journal Article
Managed aquifer recharge
Microbial community
Organic Chemicals
Oxidation-reduction potential
Synthetic aquifer
Trace organic chemicals
Water Pollutants, Chemical

Anmerkungen:

Date Completed 20.02.2020

Date Revised 20.02.2020

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.chemosphere.2019.125116

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM302877541