Change search
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf
Bacteria and geochemistry in a former uranium open pit mine - mobilization of trace metals
Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
2011 (English)Doctoral thesis, comprehensive summary (Other academic)
Abstract [en]

In mining areas around the world, chemical and biotic processes have lead to the release of toxic substances, e.g. metals. Microbial processes influence metal speciation, while the chemical environment shapes and controls microbial populations. This thesis has two parts and the papers cover various aspects of metal-to-microbe links in a former uranium mine at Ranstad, Sweden.

The first part of the thesis examines bacteria-induced metal mobilization by the cultivation of Pseudomonas fluorescens with ore and minerals from the Ranstad mine. The presence of a mineral source stimulated bacterial growth. Pyoverdine-type siderophores typical for P. fluorescens were produced, but also other types of siderophores. The bacterial mobilization of metals is implied by the agreement in concentrations of Fe-pyoverdine complex and soluble Fe, and by the concentrations of Ni and Co in solution. U was mobilized from the ore as a result of bacterial growth raising pH.

The second part of the thesis focus on the partitioning of metals and their links to the microbial communities in the water of the former open pit mine, Lake Tranebärssjön. The lake was pH-neutral to alkaline, highly stratified, and had an anoxic hypolimnion with high concentrations of metals and SO42-. Size fractionation showed the dissolved fraction dominating for most metals, while the particulate and colloidal fractions dominated for Fe. Chemical equilibrium models agreed reasonably well with these results. In the pyrosequencing study of the bacterial community, depth-related changes in water chemistry corresponded to a distinct shift in the microbial community, indicating a chemical control. The presence of metal- and SO42--reducing bacteria suggests a possible microbe – chemistry connection.

The findings of this thesis could be used for the restoration and remediation of mining sites, and provides information on factors governing the establishment and control of bacterial populations in freshwaters.

Place, publisher, year, edition, pages
Stockholm: Department of Applied Environmental Science (ITM), Stockholm University , 2011. , 48 p.
Keyword [en]
Pseudomonas fluorescens, siderophore, Ranstad, alum shale, iron, pyrosequencing, redox, size fractionation
National Category
Natural Sciences
Research subject
Applied Environmental Science
Identifiers
URN: urn:nbn:se:su:diva-55111ISBN: 978-91-7447-241-7 (print)OAI: oai:DiVA.org:su-55111DiVA: diva2:401327
Public defence
2011-04-08, De Geersalen, Geovetenskapens hus, Svante Arrhenius väg 14, Stockholm, 13:00 (English)
Opponent
Supervisors
Note
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript. Available from: 2011-03-17 Created: 2011-03-01 Last updated: 2011-04-15Bibliographically approved
List of papers
1. Mobilization of metals from uranium mine waste: the role of pyoverdines produced by Pseudomonas fluorescens
Open this publication in new window or tab >>Mobilization of metals from uranium mine waste: the role of pyoverdines produced by Pseudomonas fluorescens
2010 (English)In: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 8, no 4, 278-292 p.Article in journal (Refereed) Published
Abstract [en]

Microorganisms produce chelating agents, such as siderophores and other ligands, which allow them to mobilize and scavenge essential elements from the environment when bioavailability is low. To better understand the effects of biologically mediated leaching of metals from mine waste, Pseudomonas fluorescens was cultivated in the presence of processed ore from the former uranium mine in Ranstad, southern Sweden. Light conditions, the concentration of the mineral source and oxygen availability were varied. The presence of ore in the culture flasks enhanced bacterial growth and raised the pH of the culture medium. Increasing the amount of ore or enhancing aeration of the medium further encouraged cell growth and pH rise. Bacteria mobilized Fe, Ni and Co from the ore. Fe-siderophore complexes were detected and estimated to be present at approximately 9 μm. In the presence of bacteria and light, dissolved Fe and U concentrations were higher compared to dark conditions. Increasing the amount of ore resulted in higher dissolved Ni concentrations but lower dissolved Fe, most likely due to precipitate formation. Data from this study support siderophore production by bacteria that allowed mobilization of essential nutrients from the processed ore. However, the availability of potentially toxic metals like Ni and U may also be enhanced. Microbial-promoted mobilization could contribute to leaching of toxic metals in current and historic mining areas. This process should be considered during design and implementation of remediation projects where trace metals are of environmental concern.

National Category
Natural Sciences
Research subject
Applied Environmental Science
Identifiers
urn:nbn:se:su:diva-43170 (URN)10.1111/j.1472-4669.2010.00241.x (DOI)000280997500003 ()
Available from: 2010-10-01 Created: 2010-10-01 Last updated: 2017-12-12Bibliographically approved
2. Microbial mobilization of uranium from shale mine waste
Open this publication in new window or tab >>Microbial mobilization of uranium from shale mine waste
Show others...
2006 (English)In: Geomicrobiology Journal, ISSN 0149-0451, E-ISSN 1521-0529, Vol. 23, no 3-4, 157-164 p.Article in journal (Refereed) Published
Abstract [en]

The alum shale in the Billingen area in southern Sweden was mined in Ranstad for 5 years during the 1960s. The crushed tailings (processed and unprocessed) were left behind when the Ranstad mine was closed that has caused leaching of metals to the surroundings. The siderophore producing bacterium Pseudomonas fluorescens (sp, SE Sweden) was grown in batch cultures for 5 to 8 days with naturally weathered (unprocessed) uranium ore (0.0029% U by weight), kolm (0.52% U by weight) and acid-leached ore (0.0099% U by weight) in chemically defined media (unbuffered and buffered). Pseudomonas fluorescens grown with ore and unbuffered medium changed the pH from 4.7 to 9.3 and leached out 0.016 to 0.9% (normalized to surface area) of the total amount of U from the different ores. Incubation of the acid-leached ore with bacteria in buffered medium leached out 0.04% of the total U. Uranium was leached out selectively at all conditions, but this could be a pH effect, as pH increased at the same time as the U concentrations did. The observed release of Fe was most likely attributed to the production of microbial siderophores (Fe3+ specific chelators) since Fe3+ has a low solubility at pH > 4. As siderophores contain a number of chelating groups they may still function as complexators even in partly degraded form also for other metals than Fe. Thus, the production of microbial chelators could contribute to the elevated metal concentrations in the drainage water from the closed Ranstad mine, as abiotic processes cannot fully explain these high metal concentrations. In the extension: ligand promoted leaching of toxic elements could also be the key to bioremediation as there is a need for nontoxic cleanup methods for metal contaminated sites.

Keyword
microbial, mobilization, Pseudomonas fluorescens, siderophore, uranium
National Category
Natural Sciences
Research subject
Applied Environmental Science
Identifiers
urn:nbn:se:su:diva-43171 (URN)10.1080/01490450600599197 (DOI)
Available from: 2010-10-01 Created: 2010-10-01 Last updated: 2017-12-12Bibliographically approved
3. Geochemistry of metals in a former uranium open pit mine – size fractionation of the water column
Open this publication in new window or tab >>Geochemistry of metals in a former uranium open pit mine – size fractionation of the water column
Show others...
(English)Manuscript (preprint) (Other academic)
National Category
Inorganic Chemistry Environmental Sciences
Research subject
Environmental Chemistry
Identifiers
urn:nbn:se:su:diva-54724 (URN)
Available from: 2011-03-01 Created: 2011-02-14 Last updated: 2011-03-02Bibliographically approved
4. Bacterial community composition in an artificial lake of a former open pit mine – effects of extreme chemistry and anoxic conditions
Open this publication in new window or tab >>Bacterial community composition in an artificial lake of a former open pit mine – effects of extreme chemistry and anoxic conditions
(English)Manuscript (preprint) (Other academic)
National Category
Natural Sciences
Research subject
Applied Environmental Science
Identifiers
urn:nbn:se:su:diva-54725 (URN)
Available from: 2011-03-01 Created: 2011-02-14 Last updated: 2011-03-02Bibliographically approved

Open Access in DiVA

No full text

Search in DiVA

By author/editor
Edberg, Frida
By organisation
Department of Applied Environmental Science (ITM)
Natural Sciences

Search outside of DiVA

GoogleGoogle Scholar

isbn
urn-nbn

Altmetric score

isbn
urn-nbn
Total: 332 hits
CiteExportLink to record
Permanent link

Direct link
Cite
Citation style
  • apa
  • ieee
  • modern-language-association-8th-edition
  • vancouver
  • Other style
More styles
Language
  • de-DE
  • en-GB
  • en-US
  • fi-FI
  • nn-NO
  • nn-NB
  • sv-SE
  • Other locale
More languages
Output format
  • html
  • text
  • asciidoc
  • rtf