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Allard, B., Sjöberg, S., Sjöberg, V., Skogby, H. & Karlsson, S. (2023). Metal Exchangeability in the REE-Enriched Biogenic Mn Oxide Birnessite from Ytterby, Sweden. Minerals, 13(8), Article ID 1023.
Open this publication in new window or tab >>Metal Exchangeability in the REE-Enriched Biogenic Mn Oxide Birnessite from Ytterby, Sweden
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2023 (English)In: Minerals, E-ISSN 2075-163X, Vol. 13, no 8, article id 1023Article in journal (Refereed) Published
Abstract [en]

A black substance exuding from fractures was observed in 2012 in Ytterby mine, Sweden, and identified in 2017 as birnessite with the composition Mx[Mn(III,IV)](2)O-4 center dot(H2O)n. M is usually calcium and sodium, with x around 0.5. The Ytterby birnessite is unique, with M being calcium, magnesium, and also rare earth elements (REEs) constituting up to 2% of the total metal content. The biogenic origin of the birnessite was established in 2018. Analysis of the microbial processes leading to the birnessite formation and the REE enrichment has continued since then. The process is fast and dynamic, as indicated by the depletion of manganese and of REE and other metals in the fracture water during the passage over the precipitation zone in the mine tunnel. Studies of the exchangeability of metals in the structure are the main objective of the present program. Exposure to solutions of sodium, calcium, lanthanum, and iron led to exchanges and altered distribution of the metals in the birnessite, however, generating phases with almost identical structures after the exchanges, and no new mineral phases were detected. Exchangeability was more efficient for trivalent elements (REE) over divalent (calcium) and monovalent (sodium) elements of a similar size (ionic radii 90-100 pm).

Place, publisher, year, edition, pages
MDPI, 2023
Keywords
Ytterby mine, biogenic Mn mineralization, birnessite, rare earth elements enrichment
National Category
Geochemistry
Identifiers
urn:nbn:se:oru:diva-108411 (URN)10.3390/min13081023 (DOI)001055746500001 ()2-s2.0-85168870545 (Scopus ID)
Available from: 2023-09-27 Created: 2023-09-27 Last updated: 2024-01-17Bibliographically approved
Nilsson, C., Sjöberg, V., Grandin, A., Karlsson, S., Allard, B. & von Kronhelm, T. (2022). Phosphorus speciation in sewage sludge from three municipal wastewater treatment plants in Sweden and their ashes after incineration. Waste Management & Research, 40(8), 1267-1276, Article ID 734242X211065231.
Open this publication in new window or tab >>Phosphorus speciation in sewage sludge from three municipal wastewater treatment plants in Sweden and their ashes after incineration
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2022 (English)In: Waste Management & Research, ISSN 0734-242X, E-ISSN 1096-3669, Vol. 40, no 8, p. 1267-1276, article id 734242X211065231Article in journal (Refereed) Published
Abstract [en]

Given the high efficiency in phosphorus removal at municipal wastewater treatment plants (MMWWTP), sewage sludge constitutes a promising resource for phosphorus (P) recovery. Sewage sludge is, however, a complex matrix and its direct use as fertiliser is limited by its content of metals/metalloids and organic pollutants. In order to increase its usability as a potential resource of P, there is a need for increased knowledge on phosphorus speciation in these matrices. The sludge composition is highly influenced by local conditions (i.e. wastewater composition and treatment method), and it is therefore important to study sludge from several MMWWTPs. In this study, three different protocols for sequential extraction were utilised to investigate the chemical speciation of phosphorus in sludge from three different MMWWTP sludges in Sweden, as well as in corresponding ashes following incineration. The results showed that the total amounts of phosphorus ranged from 26 to 32 mg g-1 sludge (dry weight), of which 79-94% was inorganically bound (IP). In the sludge, 21-30% of the IP was associated with calcium (Ca-P), which is the preferred species for fertiliser production. Following incineration, this fraction increased to 54-56%, mainly due to transformation of iron-associated phosphorus (Fe-P), while aluminium-associated species of phosphorus (Al-P) remained unaltered. The results from this study confirm that incineration is a suitable treatment for sewage sludge in terms of potential phosphorus recovery.

Place, publisher, year, edition, pages
Sage Publications, 2022
Keywords
Sewage sludge, bioavailability, incineration, phosphorus, recirculation, speciation, sustainability, wastewater
National Category
Energy Engineering
Identifiers
urn:nbn:se:oru:diva-96079 (URN)10.1177/0734242X211065231 (DOI)000736222100001 ()34920692 (PubMedID)2-s2.0-85121694485 (Scopus ID)
Note

Funding agency:

Norrtorp Kumla Environmental foundation

Available from: 2021-12-21 Created: 2021-12-21 Last updated: 2022-09-12Bibliographically approved
Åhlgren, K., Sjöberg, V., Allard, B. & Bäckström, M. (2021). Groundwater chemistry affected by trace elements (As, Mo, Ni, U and V) from a burning alum shale waste deposit, Kvarntorp, Sweden. Environmental Science and Pollution Research, 28(23), 30219-30241
Open this publication in new window or tab >>Groundwater chemistry affected by trace elements (As, Mo, Ni, U and V) from a burning alum shale waste deposit, Kvarntorp, Sweden
2021 (English)In: Environmental Science and Pollution Research, ISSN 0944-1344, E-ISSN 1614-7499, Vol. 28, no 23, p. 30219-30241Article in journal (Refereed) Published
Abstract [en]

Worldwide, black shales and shale waste are known to be a potential source of metals to the environment. This project demonstrates ongoing weathering and evaluates leaching processes at a 100-m-high shale waste deposit closed in the 1960s. Some deep parts of the deposit are still burning with temperatures exceeding 500 °C. To demonstrate ongoing weathering and leaching, analyses of groundwater and solid samples of shale and shale waste have been undertaken. Largest impact on groundwater quality was observed downstream the deposit, where elevated temperatures also indicate a direct impact from the burning waste deposit. Groundwater quality is largely controlled by pH and redox conditions (e.g., for arsenic, nickel, molybdenum, uranium and vanadium), and the mixture of different waste materials, including pyrite (acidic leachates) and carbonates (neutralizing and buffering pH). Analyses of shale waste from the deposit confirm the expected pyrite weathering with high concentrations of iron, nickel and uranium in the leachates. No general time trends could be distinguished for the groundwater quality from the monitoring in 2004-2019. This study has shown that black shale waste deposits can have a complex long-term impact on the surrounding environment.

Place, publisher, year, edition, pages
Springer, 2021
Keywords
Black shale, Groundwater chemistry, Trace elements
National Category
Environmental Sciences
Identifiers
urn:nbn:se:oru:diva-89618 (URN)10.1007/s11356-021-12784-2 (DOI)000617854700001 ()33586108 (PubMedID)2-s2.0-85101014604 (Scopus ID)
Note

Funding Agency:

Örebro University  

Available from: 2021-02-16 Created: 2021-02-16 Last updated: 2021-11-23Bibliographically approved
Sjöberg, S., Yu, C., Stairs, C. W., Allard, B., Hallberg, R., Henriksson, S., . . . Dupraz, C. (2021). Microbe-Mediated Mn Oxidation: A Proposed Model of Mineral Formation. Minerals, 11(10), Article ID 1146.
Open this publication in new window or tab >>Microbe-Mediated Mn Oxidation: A Proposed Model of Mineral Formation
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2021 (English)In: Minerals, E-ISSN 2075-163X, Vol. 11, no 10, article id 1146Article in journal (Refereed) Published
Abstract [en]

Manganese oxides occur in a wide range of environmental settings either as coatings on rocks, sediment, and soil particles, or as discrete grains. Although the production of biologically mediated Mn oxides is well established, relatively little is known about microbial-specific strategies for utilizing Mn in the environment and how these affect the morphology, structure, and chemistry of associated mineralizations. Defining such strategies and characterizing the associated mineral properties would contribute to a better understanding of their impact on the local environment and possibly facilitate evaluation of biogenicity in recent and past Mn accumulations. Here, we supplement field data from a Mn rock wall deposit in the Ytterby mine, Sweden, with data retrieved from culturing Mn oxidizers isolated from this site. Microscopic and spectroscopic techniques are used to characterize field site products and Mn precipitates generated by four isolated bacteria (Hydrogenophaga sp., Pedobacter sp., Rhizobium sp., and Nevskia sp.) and one fungal-bacterial co-culture (Cladosporium sp.-Hydrogenophaga sp. Rhizobium sp.-Nevskia sp.). Two of the isolates (Pedobacter sp. and Nevskia sp.) are previously unknown Mn oxidizers. At the field site, the onset of Mn oxide mineralization typically occurs in areas associated with globular wad-like particles and microbial traces. The particles serve as building blocks in the majority of the microstructures, either forming the base for further growth into laminated dendrites-botryoids or added as components to an existing structure. The most common nanoscale structures are networks of Mn oxide sheets structurally related to birnessite. The sheets are typically constructed of very few layers and elongated along the octahedral chains. In places, the sheets bend and curl under to give a scroll-like appearance. Culturing experiments show that growth conditions (biofilm or planktonic) affect the ability to oxidize Mn and that taxonomic affiliation influences crystallite size, structure, and average oxidation state as well as the onset location of Mn precipitation.

Place, publisher, year, edition, pages
MDPI, 2021
Keywords
Hydrogenophaga, Pedobacter, Nevskia, Rhizobium, Cladosporium, Ytterby mine, Mn oxidizers, Mn mineralization, biofilm, birnessite
National Category
Geochemistry
Identifiers
urn:nbn:se:oru:diva-95491 (URN)10.3390/min11101146 (DOI)000715479000001 ()2-s2.0-85117167021 (Scopus ID)
Funder
Swedish Research Council, 2018-04167
Note

Funding agencies:

Faculty of Science at Stockholm University, Sci Life Lab grant number SU FV-2.1.1-1843-17

Umeå Center for Electron Microscopy (UCEM)

Umeå University and the National Microscopy Infrastructure and Swedish Researh Council 2020-05071

MAX IV Laboratory for time on Balder Beamline 20190277

Stockholm University Library

Available from: 2021-11-18 Created: 2021-11-18 Last updated: 2024-01-17Bibliographically approved
Sjöberg, S., Stairs, C., Allard, B., Hallberg, R., Homa, F., Martin, T., . . . Dupraz, C. (2020). Bubble biofilm: Bacterial colonization of air-air interface. Biofilm, 2, Article ID 100030.
Open this publication in new window or tab >>Bubble biofilm: Bacterial colonization of air-air interface
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2020 (English)In: Biofilm, E-ISSN 2590-2075, Vol. 2, article id 100030Article in journal (Refereed) Published
Abstract [en]

Microbial mats or biofilms are known to colonize a wide range of substrates in aquatic environments. These dense benthic communities efficiently recycle nutrients and often exhibit high tolerance to environmental stressors, characteristics that enable them to inhabit harsh ecological niches. In some special cases, floating biofilms form at the air-water interface residing on top of a hydrophobic microlayer. Here, we describe biofilms that reside at the air-air interface by forming gas bubbles (bubble biofilms) in the former Ytterby mine, Sweden. The bubbles are built by micrometer thick membrane-like biofilm that holds enough water to sustain microbial activity. Molecular identification shows that the biofilm communities are dominated by the neuston bacterium Nevskia. Gas bubbles contain mostly air with a slightly elevated concentration of carbon dioxide. Biofilm formation and development was monitored in situ using a time-lapse camera over one year, taking one image every second hour. The bubbles were stable over long periods of time (weeks, even months) and gas build-up occurred in pulses as if the bedrock suddenly exhaled. The result was however not a passive inflation of a dying biofilm becoming more fragile with time (as a result of overstretching of the organic material). To the contrary, microbial growth lead to a more robust, hydrophobic bubble biofilm that kept the bubbles inflated for extended periods (several weeks, and in some cases even months).

Place, publisher, year, edition, pages
Elsevier, 2020
Keywords
Air-air interface, Biofilm, Neuston, Nevskia, Shallow subsurface, Ytterby mine
National Category
Environmental Sciences
Identifiers
urn:nbn:se:oru:diva-88538 (URN)10.1016/j.bioflm.2020.100030 (DOI)000658274500020 ()33447815 (PubMedID)2-s2.0-85096640774 (Scopus ID)
Funder
Swedish Foundation for Strategic Research, SSF-FFL5Swedish Research Council, 2015-04959
Note

Funding Agencies:

Faculty of Science at Stockholm University, SciLifeLab, Pilot project SU FV-2.1.1-1843-17

European Research Council (ERC) 310039-PUZZLE_CELL

European Molecular Biology Organization (EMBO) ALTF-997-2015

Natural Sciences and Engineering Research Council of Canada (NSERC) CGIAR PDF-487174-2016

Available from: 2021-01-18 Created: 2021-01-18 Last updated: 2023-01-25Bibliographically approved
Åhlgren, K., Sjöberg, V., Grawunder, A., Allard, B. & Bäckström, M. (2020). Chemistry of Acidic and Neutralized Alum Shale Pit Lakes 50 Years After Mine Closure, Kvarntorp, Sweden. Mine Water and the Environment, 39(3), 481-497
Open this publication in new window or tab >>Chemistry of Acidic and Neutralized Alum Shale Pit Lakes 50 Years After Mine Closure, Kvarntorp, Sweden
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2020 (English)In: Mine Water and the Environment, ISSN 1025-9112, E-ISSN 1616-1068, Vol. 39, no 3, p. 481-497Article in journal (Refereed) Published
Abstract [en]

Several large pits were left after alum shale was mined from 1942 to 1966 in the Kvarntorp area of Sweden. Of these, the pit lakes Polen and Norrtorpssjon are the focus of this study. They have elevated levels of Na, K, Mg, Ca, Al, Mn, Fe, and sulphate, as well as trace elements, from weathering of the exposed shale. Both lakes had a stable pH below 4 until 1996 when the pH in Norrtorpssjon started to increase, exceeding 8 in 2010, due to inflow of leachates from alkaline waste dumped in an adjacent waste deposit, similar to a large scale anoxic limestone drain (ALD). Iron and Al concentrations decreased as the pH increased, indicating formation of particulate species which accumulate as sediments. The Co, Ni, and Zn concentrations also decreased, probably due to association with the solid phases, while Cu was less affected by the increase in pH, possibly due to formation of complexes with dissolved organic matter. Vanadium concentrations show limited solubility, while Mo concentrations increased at higher pH. Uranium concentrations decreased from above 80 mu g/L to below 10 mu g/L before rising to 30-35 mu g/L due to the formation of soluble carbonate complexes at higher pH levels. The elevated levels of Li, Sr, and U indicate that weathering has continued despite the pH change. Both pit lakes are stratified, but no seasonal overturn has been observed. Long-term behaviour of this large-scale ALD and its implications are also discussed.

Place, publisher, year, edition, pages
Springer, 2020
Keywords
Weathering, Leachate, Sediment, Vanadium, Molybdenum, Uranium
National Category
Environmental Sciences
Identifiers
urn:nbn:se:oru:diva-80750 (URN)10.1007/s10230-020-00665-y (DOI)000516394800001 ()2-s2.0-85080921121 (Scopus ID)
Note

Funding Agencies:

Örebro University  

SAKAB-Kumla Foundation  

Available from: 2020-03-20 Created: 2020-03-20 Last updated: 2020-12-16Bibliographically approved
Sjöberg, S., Stairs, C., Allard, B., Homa, F., Martin, T., Sjöberg, V., . . . Dupraz, C. (2020). Microbiomes in a manganese oxide producing ecosystem in the Ytterby mine, Sweden: impact on metal mobility. FEMS Microbiology Ecology, 96(11), Article ID fiaa169.
Open this publication in new window or tab >>Microbiomes in a manganese oxide producing ecosystem in the Ytterby mine, Sweden: impact on metal mobility
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2020 (English)In: FEMS Microbiology Ecology, ISSN 0168-6496, E-ISSN 1574-6941, Vol. 96, no 11, article id fiaa169Article in journal (Refereed) Published
Abstract [en]

Microbe-mediated precipitation of Mn-oxides enriched in rare earth elements (REE) and other trace elements was discovered in tunnels leading to the main shaft of the Ytterby mine, Sweden. Defining the spatial distribution of microorganisms and elements in this ecosystem provide a better understanding of specific niches and parameters driving the emergence of these communities and associated mineral precipitates. Along with elemental analyses, high-throughput sequencing of the following four subsystems were conducted: (1) water seeping from a rock fracture into the tunnel, (2) Mn-oxides and associated biofilm; referred to as the Ytterby Black Substance (YBS) biofilm (3) biofilm forming bubbles on the Mn-oxides; referred to as the bubble biofilm, and (4) fracture water that has passed through the biofilms. Each subsystem hosts a specific collection of microorganisms. Differentially abundant bacteria in the YBS biofilm were identified within the Rhizobiales (e.g. Pedomicrobium), PLTA13 Gammaproteobacteria, Pirellulaceae, Hyphomonadaceae, Blastocatellia and Nitrospira. These taxa, likely driving the Mn-oxide production, were not detected in the fracture water. This biofilm binds Mn, REE and other trace elements in an efficient, dynamic process, as indicated by substantial depletion of these metals from the fracture water as it passes through the Mn deposit zone. Microbe-mediated oxidation of Mn(II) and formation of Mn(III/IV)-oxides can thus have considerable local environmental impact by removing metals from aquatic environments.

Place, publisher, year, edition, pages
Oxford University Press, 2020
Keywords
Mn-oxidizers, REE fractionation, Ytterby mine, biofilms, birnessite, ecosystem, shallow subsurface
National Category
Geochemistry
Identifiers
urn:nbn:se:oru:diva-85121 (URN)10.1093/femsec/fiaa169 (DOI)000593018400006 ()32815988 (PubMedID)2-s2.0-85094933341 (Scopus ID)
Funder
Swedish Foundation for Strategic Research , SSF-FFL5Swedish Research Council, 2015-04959
Note

Funding Agencies:

European Research Council (ERC)310039-PUZZLE CELL

Faculty of Science at Stockholm University, SciLifeLab, Pilot project SU FV-2.1.1-1843-17

European Molecular Biology Organization (EMBO)ALTF-997-2015

Natural Sciences and Engineering Research Council of Canada

CGIARPDF-487174-2016

Available from: 2020-09-07 Created: 2020-09-07 Last updated: 2021-01-13Bibliographically approved
Chen, D., Rodhe, H., Emanuel, K., Seneviratne, S. I., Zhai, P., Allard, B., . . . Zhang, Q. (2020). Summary of a workshop on extreme weather events in a warming world organized by the Royal Swedish Academy of Sciences. Tellus. Series B, Chemical and physical meteorology, 72(1), Article ID 1794236.
Open this publication in new window or tab >>Summary of a workshop on extreme weather events in a warming world organized by the Royal Swedish Academy of Sciences
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2020 (English)In: Tellus. Series B, Chemical and physical meteorology, ISSN 0280-6509, E-ISSN 1600-0889, Vol. 72, no 1, article id 1794236Article in journal (Refereed) Published
Abstract [en]

Climate change is not only about changes in means of climatic variables such as temperature, precipitation and wind, but also their extreme values which are of critical importance to human society and ecosystems. To inspire the Swedish climate research community and to promote assessments of international research on past and future changes in extreme weather events against the global climate change background, the Earth Science Class of the Royal Swedish Academy of Sciences organized a workshop entitled 'Extreme weather events in a warming world' in 2019. This article summarizes and synthesizes the key points from the presentations and discussions of the workshop on changes in floods, droughts, heat waves, as well as on tropical cyclones and extratropical storms. In addition to reviewing past achievements in these research fields and identifying research gaps with a focus on Sweden, future challenges and opportunities for the Swedish climate research community are highlighted.

Place, publisher, year, edition, pages
Taylor & Francis, 2020
Keywords
climate change, extreme weather events, workshop, Sweden
National Category
Meteorology and Atmospheric Sciences
Identifiers
urn:nbn:se:oru:diva-85052 (URN)10.1080/16000889.2020.1794236 (DOI)000550013500001 ()2-s2.0-85088116376 (Scopus ID)
Funder
The Royal Swedish Academy of SciencesSwedish Research Council Formas, 2018-02858
Note

Funding Agencies:

Department of Earth Sciences at the University of Gothenburg  

Swedish strategic research program MERGE  

Swedish strategic research program BECC 

Available from: 2020-08-27 Created: 2020-08-27 Last updated: 2020-08-27Bibliographically approved
Sjöberg, S., Callac, N., Allard, B., Smittenberg, R. H. & Dupraz, C. (2018). Microbial Communities Inhabiting a Rare Earth Element Enriched Birnessite-Type Manganese Deposit in the Ytterby Mine, Sweden. Geomicrobiology Journal, 35(8), 657-674
Open this publication in new window or tab >>Microbial Communities Inhabiting a Rare Earth Element Enriched Birnessite-Type Manganese Deposit in the Ytterby Mine, Sweden
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2018 (English)In: Geomicrobiology Journal, ISSN 0149-0451, E-ISSN 1521-0529, Vol. 35, no 8, p. 657-674Article in journal (Refereed) Published
Abstract [en]

The dominant initial phase formed during microbially mediated manganese oxidation is a poorly crystalline birnessite-type phyllomanganate. The occurrence of manganese deposits containing this mineral is of interest for increased understanding of microbial involvement in the manganese cycle. A culture independent molecular approach is used as a first step to investigate the role of microorganisms in forming rare earth element enriched birnessite-type manganese oxides, associated with water bearing rock fractures in a tunnel of the Ytterby mine, Sweden. 16S rRNA gene results show that the chemotrophic bacterial communities are diverse and include a high percentage of uncultured unclassified bacteria while archaeal diversity is low with Thaumarchaeota almost exclusively dominating the population. Ytterby clones are frequently most similar to clones isolated from subsurface environments, low temperature milieus and/or settings rich in metals. Overall, bacteria are dominant compared to archaea. Both bacterial and archaeal abundances are up to four orders of magnitude higher in manganese samples than in fracture water. Potential players in the manganese cycling are mainly found within the ferromanganese genera Hyphomicrobium and Pedomicrobium, and a group of Bacteroidetes sequences that cluster within an uncultured novel genus most closely related to the Terrimonas. This study strongly suggest that the production of the YBS deposit is microbially mediated.

Place, publisher, year, edition, pages
Taylor & Francis, 2018
Keywords
Birnessite, microbial diversity, manganese oxidizing bacteria, organomineralization, subsurface microbiology
National Category
Environmental Sciences
Identifiers
urn:nbn:se:oru:diva-68158 (URN)10.1080/01490451.2018.1444690 (DOI)000437337500003 ()2-s2.0-85044755213 (Scopus ID)
Note

Funding Agency:

European Research Council  336092

Available from: 2018-07-26 Created: 2018-07-26 Last updated: 2018-07-26Bibliographically approved
Karlsson, S., Sjöberg, V. & Allard, B. (2017). Metal transport dynamics in a small watershed - Dylta bruk, Sweden. In: Bio-geo interactions: basic knowledge to application: 16th Symposium on remediation in Jena “Jenaer Sanierungskolloquium”. Conference proceedings. Paper presented at 16th Symposium on remediation, Jena, Germany, October 5-6, 2017 (pp. 23-23).
Open this publication in new window or tab >>Metal transport dynamics in a small watershed - Dylta bruk, Sweden
2017 (English)In: Bio-geo interactions: basic knowledge to application: 16th Symposium on remediation in Jena “Jenaer Sanierungskolloquium”. Conference proceedings, 2017, p. 23-23Conference paper, Oral presentation with published abstract (Other academic)
Abstract [en]

Metal transport in small streams in boreal catchments is a function of weathering rate, water balance and redistribution mechanisms. Because of these highly dynamic processes long term water quality changes are difficult to determine but needed in order to assess the impact of several local and largescale changes on local water quality.

The field site is situated at Dyltabruk, some 20 km North of Örebro in South Central Sweden. The 4 km2 catchment has deciduous and coniferous species on a granitic moraine with some 20% ofmires and fens adjacent to the oldest sulphur mine in Sweden. Grab samples were collected weekly since 2006 but more frequent during periods with large changes in water balance. The samples were analysed for general hydrochemical parameters (temperature, electrical conductivity, pH, dissolved organic carbon (DOC), inorganic carbon (IC), fulvic and humic acids and dissolved oxygen), dissolved principal anions, principal and trace metals. Standardized analytical procedures were applied. Temperature, precipitation and other climatic parameters were recorded some 2 km from thesite every 15 minutes.

The results showed a general concentration pattern where the water balance had the largest single influence. The concentrations had a seasonality inversely related to the ground water level. Inter annual variations of one to two orders of magnitude were observed for group 1 and 2 elements. For transition metals with high affinity to solid matter as well as DOC the variation reached three to four orders of magnitude. Only aluminium and iron had concentrations that occasionally exceeded solubility limits which resulted in a similar inter annual variation.

During the study period the average annual temperature and precipitation were no different (p 0.05) from the previous ten years but rainfall intensities increased. In a long term perspective the concentrations for all metals except calcium had positive trends. The tendencies remained when normalizing against chloride. The same was found for DOC, nitrate and sulphate. Hence, there is an accelerating loss of most elements that is not limited by weathering. It is uncertain, however, if the positive trends for DOC depend on increased production or a balancing release from the supply in mires and fens. In addition, there is also an indication of increasing inter annual concentration changescwith time. Although not exclusively proven such phenome would occur as a result of increased rainfall intensity. It is therefore likely that the accelerating loss of elements is a result of increased weathering rather than increasing water discharge.

National Category
Environmental Sciences
Identifiers
urn:nbn:se:oru:diva-64734 (URN)
Conference
16th Symposium on remediation, Jena, Germany, October 5-6, 2017
Available from: 2018-01-31 Created: 2018-01-31 Last updated: 2022-09-28Bibliographically approved
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-2104-4593

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