1
|
Feng F, Jiang Y, Jia Y, Lian X, Shang C, Zhao M. Exogenous-organic-matter-driven mobilization of groundwater arsenic. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2023; 15:100243. [PMID: 36896144 PMCID: PMC9989647 DOI: 10.1016/j.ese.2023.100243] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/20/2022] [Revised: 01/21/2023] [Accepted: 01/24/2023] [Indexed: 06/18/2023]
Abstract
The potential release capacity of arsenic (As) from sediment was evaluated under a high level of exogenous organic matter (EOM) with both bioreactive and chemically reactive organic matters (OMs). The OMs were characterized by FI, HIX, BIX, and SUVA254 fluorescence indices showing the biological activities were kept at a high level during the experimental period. At the genus level, Fe/Mn/As-reducing bacteria (Geobacter, Pseudomonas, Bacillus, and Clostridium) and bacteria (Paenibacillus, Acidovorax, Delftia, and Sphingomonas) that can participate in metabolic transformation using EOM were identified. The reducing condition occurs which promoted As, Fe, and Mn releases at very high concentrations of OM. However, As release increased during the first 15-20 days, followed by a decline contributed by secondary iron precipitation. The degree of As release may be limited by the reactivity of Fe (hydro)oxides. The EOM infiltration enhances As and Mn releases in aqueous conditions causing the risk of groundwater pollution, which could occur in specific sites such as landfills, petrochemical sites, and managed aquifer recharge projects.
Collapse
Affiliation(s)
- Fan Feng
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- College of Water Sciences, Beijing Normal University, Beijing, 100875, China
| | - Yonghai Jiang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Yongfeng Jia
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Xinying Lian
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Changjian Shang
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| | - Meng Zhao
- State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
- State Environmental Protection Key Laboratory of Simulation and Control of Groundwater Pollution, Chinese Research Academy of Environmental Sciences, Beijing, 100012, China
| |
Collapse
|
2
|
Underwood JC, Akob DM, Lorah MM, Imbrigiotta TE, Harvey RW, Tiedeman CR. Microbial Community Response to a Bioaugmentation Test to Degrade Trichloroethylene in a Fractured Rock Aquifer, Trenton, N.J. FEMS Microbiol Ecol 2022; 98:6617591. [PMID: 35749571 DOI: 10.1093/femsec/fiac077] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2022] [Revised: 05/12/2022] [Accepted: 06/22/2022] [Indexed: 11/12/2022] Open
Abstract
Bioaugmentation is a promising strategy for enhancing trichloroethylene (TCE) degradation in fractured rock. However, slow or incomplete biodegradation can lead to stalling at degradation byproducts such as 1,2-dichloroethene (cis-DCE) and vinyl chloride (VC). Over the course of 7 years, we examined the response of groundwater microbial populations in a bioaugmentation test where an emulsified vegetable oil solution (EOS®) and a dechlorinating consortium (KB-1®), containing the established dechlorinator Dehalococcoides, were injected into a TCE-contaminated fractured rock aquifer. Indigenous microbial communities responded within 2 days to added substrate and outcompeted KB-1®, and over the years of monitoring, several other notable turnover events were observed. Concentrations of ethene, the end product in reductive dechlorination, had the strongest correlations (p< 0.05) with members of Candidatus Colwellbacteria but their involvement in reductive dechlorination is unknown and warrants further investigation. Dehalococcoides never exceeded 0.6% relative abundance of groundwater microbial communities, despite its previously presumed importance at the site. Increased concentrations of carbon dioxide, acetic acid, and methane were positively correlated with increasing ethene concentrations; however, concentrations of cis-DCE and VC remained high by the end of the monitoring period suggesting preferential enrichment of indigenous partial dechlorinators over bioaugmented complete dechlorinators. This study highlights the importance of characterizing in situ microbial populations to understand how they can potentially enhance or inhibit augmented TCE degradation.
Collapse
Affiliation(s)
- J C Underwood
- U.S. Geological Survey, Water Mission Area, Boulder CO 80303USA
| | - D M Akob
- U.S. Geological Survey, Geology, Energy & Minerals Science Center, 12201 Sunrise Valley Drive, Mailstop 954, Reston, VA 20192USA
| | - M M Lorah
- U.S. Geological Survey, MD-DE-DC Water Science Center, 5522 Research Park Drive, Baltimore, MD 21228USA
| | - T E Imbrigiotta
- U.S. Geological Survey, New Jersey Water Science Center, 3450 Princeton Pike, Suite 110, Lawrenceville, NJ 08648USA
| | - R W Harvey
- U.S. Geological Survey, Water Mission Area, Boulder CO 80303USA
| | - C R Tiedeman
- U.S. Geological Survey, Water Mission Area, Menlo Park, CA 94025USA
| |
Collapse
|
3
|
Burbery L, Abraham P, Sutton R, Close M. Evaluation of pollution swapping phenomena from a woodchip denitrification wall targetting removal of nitrate in a shallow gravel aquifer. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 820:153194. [PMID: 35063516 DOI: 10.1016/j.scitotenv.2022.153194] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/17/2021] [Accepted: 01/12/2022] [Indexed: 06/14/2023]
Abstract
Woodchip denitrification walls offer a potentially useful way for passive in situ remediation of groundwater nitrate pollution, yet because of the low redox state they induce on the subsurface environment there is an inherent risk they can promote pollution-swapping phenomena. We evaluated pollution-swapping phenomena associated with the first two operational years of a woodchip denitrification wall that is being trialled in a fast-flowing shallow gravel aquifer of quartzo-feldspathic mineralogy. Following burial of woodchip below the water table there was immediate export of dissolved organic carbon (DOC), phosphorus and ammonium into the groundwater. Under the low redox state sustained by labile DOC, the wall initially provided 100% nitrate removal at the expense of acute and localised pollution that occurred in the form of a plume of dissolved iron, manganese and arsenic that were mobilised from the aquifer sediments, in conjunction with methane gas emission. Within one year however, the reactivity of the woodchip wall subsided to support a steady state condition in which nitrate reduction was the terminal electron acceptor process with no measurable methane emission. Having initially functioned as a sink for the potent greenhouse gas nitrous oxide (N2O), evidence is that the woodchip wall is now exporting N2O, albeit at rates less than those associated with productive agricultural land.
Collapse
Affiliation(s)
- Lee Burbery
- Institute of Environmental Science and Research Ltd. (ESR), Christchurch, New Zealand.
| | - Phil Abraham
- Institute of Environmental Science and Research Ltd. (ESR), Christchurch, New Zealand
| | - Richard Sutton
- Institute of Environmental Science and Research Ltd. (ESR), Christchurch, New Zealand
| | - Murray Close
- Institute of Environmental Science and Research Ltd. (ESR), Christchurch, New Zealand
| |
Collapse
|
4
|
Arsenic in Petroleum-Contaminated Groundwater near Bemidji, Minnesota Is Predicted to Persist for Centuries. WATER 2021. [DOI: 10.3390/w13111485] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
We used a reactive transport model to investigate the cycling of geogenic arsenic (As) in a petroleum-contaminated aquifer. We simulated As mobilization and sequestration using surface complexation reactions with Fe(OH)3 during petroleum biodegradation coupled with Fe-reduction. Model results predict that dissolved As in the plume will exceed the U.S. and EU 10 µg/L drinking water standard for ~400 years. Non-volatile dissolved organic carbon (NVDOC) in the model promotes As mobilization by exerting oxygen demand, which maintains anoxic conditions in the aquifer. After NVDOC degrades, As re-associates with Fe(OH)3 as oxygenated conditions are re-established. Over the 400-year simulation, As transport resembles a “roll front” in which: (1) arsenic sorbed to Fe(OH)3 is released during Fe-reduction coupled to petroleum biodegradation; (2) dissolved As resorbs to Fe(OH)3 at the plume’s leading edge; and (3) over time, the plume expands, and resorbed As is re-released into groundwater. This “roll front” behavior underscores the transience of sorption as an As attenuation mechanism. Over the plume’s lifespan, simulations suggest that As will contaminate more groundwater than benzene from the oil spill. At its maximum, the model simulates that ~5.7× more groundwater will be contaminated by As than benzene, suggesting that As could pose a greater long-term water quality threat than benzene in this petroleum-contaminated aquifer.
Collapse
|
5
|
Mirza BS, Muruganandam S, Meng X, Sorensen DL, Dupont RR, McLean JE. Arsenic(V) reduction in relation to Iron(III) transformation and molecular characterization of the structural and functional microbial community in sediments of a basin-fill aquifer in Northern Utah. Appl Environ Microbiol 2014; 80:3198-208. [PMID: 24632255 PMCID: PMC4018920 DOI: 10.1128/aem.00240-14] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2014] [Accepted: 03/07/2014] [Indexed: 11/20/2022] Open
Abstract
Basin-fill aquifers of the Southwestern United States are associated with elevated concentrations of arsenic (As) in groundwater. Many private domestic wells in the Cache Valley Basin, UT, have As concentrations in excess of the U.S. EPA drinking water limit. Thirteen sediment cores were collected from the center of the valley at the depth of the shallow groundwater and were sectioned into layers based on redoxmorphic features. Three of the layers, two from redox transition zones and one from a depletion zone, were used to establish microcosms. Microcosms were treated with groundwater (GW) or groundwater plus glucose (GW+G) to investigate the extent of As reduction in relation to iron (Fe) transformation and characterize the microbial community structure and function by sequencing 16S rRNA and arsenate dissimilatory reductase (arrA) genes. Under the carbon-limited conditions of the GW treatment, As reduction was independent of Fe reduction, despite the abundance of sequences related to Geobacter and Shewanella, genera that include a variety of dissimilatory iron-reducing bacteria. The addition of glucose, an electron donor and carbon source, caused substantial shifts toward domination of the bacterial community by Clostridium-related organisms, and As reduction was correlated with Fe reduction for the sediments from the redox transition zone. The arrA gene sequencing from microcosms at day 54 of incubation showed the presence of 14 unique phylotypes, none of which were related to any previously described arrA gene sequence, suggesting a unique community of dissimilatory arsenate-respiring bacteria in the Cache Valley Basin.
Collapse
Affiliation(s)
- Babur S Mirza
- Utah Water Research Laboratory, Utah State University, Logan, Utah, USA
| | | | | | | | | | | |
Collapse
|
6
|
Wei N, Finneran KT. Low and high acetate amendments are equally as effective at promoting complete dechlorination of trichloroethylene (TCE). Biodegradation 2012; 24:413-25. [PMID: 23064845 DOI: 10.1007/s10532-012-9598-x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/28/2012] [Accepted: 09/29/2012] [Indexed: 11/26/2022]
Abstract
Experiments with trichloroethylene-contaminated aquifer material demonstrated that TCE, cis-DCE, and VC were completely degraded with concurrent Fe(III) or Fe(III) and sulfate reduction when acetate was amended at stoichiometric concentration; competing TEAPs did not inhibit ethene production. Adding 10× more acetate did not increase the rate or extent of TCE reduction, but only increased methane production. Enrichment cultures demonstrated that ~90 μM TCE or ~22 μM VC was degraded primarily to ethene within 20 days with concurrent Fe(III) or Fe(III) + sulfate reduction. The dechlorination rates were comparable between the low and high acetate concentrations (0.36 vs 0.34 day(-1), respectively), with a slightly slower rate in the 10× acetate amended incubations. Methane accumulated to 13.5 (±0.5) μmol/tube in the TCE-degrading incubations with 10× acetate, and only 1.4 (±0.1) μmol/tube with low acetate concentration. Methane accumulated to 16 (±1.5) μmol/tube in VC-degrading enrichment with 10× acetate and 2 (±0.1) μmol/tube with stoichiometric acetate. The estimated fraction of electrons distributed to methanogenesis increased substantially when excessive acetate was added. Quantitative PCR analysis indicated that 10× acetate did not enhance Dehalococcoides biomass but rather increased the methanogen abundance by nearly one order of magnitude compared to that with stoichiometric acetate. The data suggest that adding low levels of substrate may be equally if not more effective as high concentrations, without producing excessive methane. This has implications for field remediation efforts, in that adding excess electron donor may not benefit the reactions of interest, which in turn will increase treatment costs without direct benefit to the stakeholders.
Collapse
Affiliation(s)
- Na Wei
- Department of Civil and Environmental Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | | |
Collapse
|
7
|
Chambon JC, Bjerg PL, Scheutz C, Baelum J, Jakobsen R, Binning PJ. Review of reactive kinetic models describing reductive dechlorination of chlorinated ethenes in soil and groundwater. Biotechnol Bioeng 2012; 110:1-23. [DOI: 10.1002/bit.24714] [Citation(s) in RCA: 81] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2012] [Revised: 08/13/2012] [Accepted: 08/16/2012] [Indexed: 11/08/2022]
|
8
|
Wei N, Finneran KT. Influence of ferric iron on complete dechlorination of trichloroethylene (TCE) to ethene: Fe(III) reduction does not always inhibit complete dechlorination. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:7422-7430. [PMID: 21777002 DOI: 10.1021/es201501a] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
The effects of Fe(III) reduction on TCE, cis-DCE, and VC dechlorination were studied in both contaminated aquifer material and enrichment cultures. The results from sediment batch experiments demonstrated that Fe(III) reduction did not inhibit complete dechlorination. TCE was reduced concurrently with Fe(III) in the first 40 days of the incubations. While all incubations (plus and minus Fe(III)) generated approximately the same mass of ethene within the experimental time frame, Fe(III) speciation (ferrihydrite versus Fe(III)-NTA) had an impact on daughter product distribution and dechlorination kinetics. 16S rRNA gene clone library sequencing identified Dehalococcoides and Geobacteraceae as dominant populations, which included G. lovleyi like organisms. Quantitative PCR targeting 16S rRNA genes and Reductive Dehalogenase genes (tceA, bvcA, vcrA) indicated that Dehalococcoides and Geobacteraceae were enriched concurrently in the TCE-degrading, Fe(III)-reducing sediments. Enrichment cultures demonstrated that soluble Fe(III) had a greater impact on cis-DCE and VC reduction than solid-phase Fe(III). Geobacteraceae and Dehalococcoides were also coenriched in the liquid cultures, and the Dehalococcoides abundance in the presence of Fe(III) was not significantly different from those in the cultures without Fe(III). Hydrogen reached steady-state concentrations most amenable to complete dechlorination very quickly when Fe(III) was present in the culture, suggesting that Fe(III) reduction may actually help dechlorination. This was contrasted to hydrogen levels in nitrate-amended enrichments, in which hydrogen concentration was too low for any chlororespiration.
Collapse
Affiliation(s)
- Na Wei
- Environmental Engineering and Earth Sciences, Clemson University, 168 Rich Laboratory, Anderson, South Carolina 29625, United States
| | | |
Collapse
|
9
|
Barringer JL, Mumford A, Young LY, Reilly PA, Bonin JL, Rosman R. Pathways for arsenic from sediments to groundwater to streams: biogeochemical processes in the Inner Coastal Plain, New Jersey, USA. WATER RESEARCH 2010; 44:5532-5544. [PMID: 20580401 DOI: 10.1016/j.watres.2010.05.047] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/23/2009] [Revised: 05/05/2010] [Accepted: 05/25/2010] [Indexed: 05/29/2023]
Abstract
The Cretaceous and Tertiary sediments that underlie the Inner Coastal Plain of New Jersey contain the arsenic-rich mineral glauconite. Streambed sediments in two Inner Coastal Plain streams (Crosswicks and Raccoon Creeks) that traverse these glauconitic deposits are enriched in arsenic (15-25mg/kg), and groundwater discharging to the streams contains elevated levels of arsenic (>80μg/L at a site on Crosswicks Creek) with arsenite generally the dominant species. Low dissolved oxygen, low or undetectable levels of nitrate and sulfate, detectable sulfide concentrations, and high concentrations of iron and dissolved organic carbon (DOC) in the groundwater indicate that reducing environments are present beneath the streambeds and that microbial activity, fueled by the DOC, is involved in releasing arsenic and iron from the geologic materials. In groundwater with the highest arsenic concentrations at Crosswicks Creek, arsenic respiratory reductase gene (arrA) indicated the presence of arsenic-reducing microbes. From extracted DNA, 16s rRNA gene sequences indicate the microbial community may include arsenic-reducing bacteria that have not yet been described. Once in the stream, iron is oxidized and precipitates as hydroxide coatings on the sediments. Arsenite also is oxidized and co-precipitates with or is sorbed to the iron hydroxides. Consequently, dissolved arsenic concentrations are lower in streamwater than in the groundwater, but the arsenic contributed by groundwater becomes part of the arsenic load in the stream when sediments are suspended during high flow. A strong positive relation between concentrations of arsenic and DOC in the groundwater samples indicates that any process-natural or anthropogenic-that increases the organic carbon concentration in the groundwater could stimulate microbial activity and thus increase the amount of arsenic that is released from the geologic materials.
Collapse
Affiliation(s)
- Julia L Barringer
- US Geological Survey, New Jersey Water Science Center, 810 Bear Tavern Road, West Trenton, NJ 08628, USA.
| | | | | | | | | | | |
Collapse
|
10
|
|
11
|
Weber FA, Hofacker AF, Voegelin A, Kretzschmar R. Temperature dependence and coupling of iron and arsenic reduction and release during flooding of a contaminated soil. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2010; 44:116-22. [PMID: 20039741 DOI: 10.1021/es902100h] [Citation(s) in RCA: 104] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/05/2023]
Abstract
Arsenic (As) in soils and sediments is commonly mobilized when anoxic conditions promote microbial iron (Fe) and As reduction. Recent laboratory studies and field observations have suggested a decoupling between Fe and As reduction and release, but the links between these processes are still not well understood. In microcosm experiments, we monitored the formation of Fe(II) and As(III) in the porewater and in the soil solid-phase during flooding of a contaminated floodplain soil at temperatures of 23, 14, and 5 degrees C. At all temperatures, flooding induced the development of anoxic conditions and caused increasing concentrations of dissolved Fe(II) and As(III). Decreasing the temperature from 23 to 14 and 5 degrees C strongly slowed down soil reduction and Fe and As release. Speciation of As in the soil solid-phase by X-ray absorption spectroscopy (XAS) and extraction of the Fe(II) that has formed by reductive Fe(III) (hydr)oxide dissolution revealed that less than 3.9% of all As(III) and less than 3.2% of all Fe(II) formed during 52 days of flooding at 23 degrees C were released into the porewater, although 91% of the initially ascorbate-extractable Fe and 66% of the total As were reduced. The amount of total As(III) formed during soil reduction was linearly correlated to the amount of total Fe(II) formed, indicating that the rate of As(V) reduction was controlled by the rate of microbial Fe(III) (hydr)oxide reduction.
Collapse
Affiliation(s)
- Frank-Andreas Weber
- Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, CHN, 8092 Zurich, Switzerland
| | | | | | | |
Collapse
|
12
|
Wang S, Zhao X. On the potential of biological treatment for arsenic contaminated soils and groundwater. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2009; 90:2367-2376. [PMID: 19269736 DOI: 10.1016/j.jenvman.2009.02.001] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/10/2008] [Revised: 01/14/2009] [Accepted: 02/08/2009] [Indexed: 05/27/2023]
Abstract
Bioremediation of arsenic contaminated soils and groundwater shows a great potential for future development due to its environmental compatibility and possible cost-effectiveness. It relies on microbial activity to remove, mobilize, and contain arsenic through sorption, biomethylation-demethylation, complexation, coprecipitation, and oxidation-reduction processes. This paper gives an evaluation on the feasibility of using biological methods for the remediation of arsenic contaminated soils and groundwater. Ex-situ bioleaching can effectively remove bulk arsenic from contaminated soils. Biostimulation such as addition of carbon sources and mineral nutrients can be applied to promote the leaching rate. Biosorption can be used either ex-situ or in-situ to remove arsenic from groundwater by sorption to biomass and/or coprecipitation with biogenic solids or sulfides. Introduction of proper biosorbents or microorganisms to produce active biosorbents in-situ is the key to the success of this method. Phytoremediation depends on arsenic-hyperaccumulating plants to remove arsenic from soils and shallow groundwater by translocating it into plant tissues. Engineering genetic strategies can be employed to increase the arsenic-hyperaccumulating capacity of the plants. Biovolatilization may be developed potentially as an ex-situ treatment technology. Further efforts are needed to focus on increasing the volatilization rate and the post-treatment of volatilization products.
Collapse
Affiliation(s)
- Suiling Wang
- Henan Development & Reform Commission, Zhengzhou, Henan, PR China.
| | | |
Collapse
|
13
|
Velasco Ayuso S, Guerrero MC, Montes C, López-Archilla AI. Spatiotemporal distribution of microbial communities in a coastal, sandy aquifer system (Doñana, SW Spain). GEOBIOLOGY 2009; 7:66-81. [PMID: 19200147 DOI: 10.1111/j.1472-4669.2008.00183.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
The aquifer system of Doñana (SW Spain) represents the most important freshwater source in the Doñana Natural Area. Its spatiotemporal dynamics favours the hydrological connection between surface and subsurface ecosystems, and promotes matter fluxes among the different terrestrial and aquatic systems present here. This aquifer has been intensively studied from a hydrogeological point of view but little is known from an ecological perspective. In order to understand the ecological roles played by microbial communities in this system, we conducted a long-term seasonal study of bacterial abundance, cell biomass, bacterial biomass and functional activities over a 2-year period. Bacterial abundance ranged between 2.11 +/- 1.79 x 10(5) and 8.58 +/- 6.99 x 10(7) bacteria mL(-1) groundwater, average cell biomass was estimated to be 77.01 +/- 31.56 fgC and bacterial biomass varied between 8.99 +/- 4.10 x 10(-2) and 5.65 +/- 0.70 microgC mL(-1). Iron-related bacteria showed the highest activities among the functional groups studied. Moreover, among the variables that usually control spatial distributions of microbial communities in aquifer systems, depth did not have a relevant effect on this aquifer, at least in the range of depths studied, but grain size, probably due to its direct effects on hydrogeological parameters, such as permeability or porosity, appeared to exert moderate control, principally in terms of bacterial abundance. Finally, significant seasonal differences in the means of these microbiological variables were also observed; temperature seems to be the main factor controlling the temporal distribution of microbial communities in this aquifer system.
Collapse
Affiliation(s)
- S Velasco Ayuso
- Departamento de Ecología, Facultad de Ciencias, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain.
| | | | | | | |
Collapse
|
14
|
Duan M, Xie Z, Wang Y, Xie X. Microcosm studies on iron and arsenic mobilization from aquifer sediments under different conditions of microbial activity and carbon source. ACTA ACUST UNITED AC 2008. [DOI: 10.1007/s00254-008-1384-z] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
|