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  • 251.
    Dinasquet, Julie
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Univ Copenhagen, Marine Biol Sect, DK-3000 Helsingor, Denmark.
    Kragh, Theis
    Schroter, Marie-Louise
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Sondergaard, Morten
    Riemann, Lasse
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Univ Copenhagen, Marine Biol Sect, DK-3000 Helsingor, Denmark.
    Functional and compositional succession of bacterioplankton in response to a gradient in bioavailable dissolved organic carbon2013In: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 15, no 9, p. 2616-2628Article in journal (Refereed)
    Abstract [en]

    Studies indicate that bacterial taxa utilize different fractions of the dissolved organic carbon (DOC) pool, while others suggest functional redundancy among constituents of bacterioplankton, implying only a weak coupling between community structure and function. We examined bacterial compositional and functional [ectoenzymatic activities and growth efficiency; bacterial growth efficiency (BGE)] responses to a gradient in bioavailable DOC (bDOC). This was achieved over 10 days in DOC utilization assays containing Baltic Sea water with variable amounts of natural bDOC. Measurements of bacterial growth, O-2 and DOC consumption in the assays using non-invasive sampling showed that BGE changed over time and that the bDOC utilized accounted for 4-13% of the DOC pool. Pyrosequencing of 16S rRNA genes demonstrated minor differences at the phylum level between samples, whereas larger successional differences were discernible at lower phylogenetic levels. Our study suggests that changes in concentrations of bDOC affect bacterioplankton BGE and community structure by selecting for some taxa while the relative abundance of most taxa remained unaffected. Ectoenzymes activities suggested preferential degradation of protein-rich compounds by bacteria, switching to carbohydrate-rich DOC when proteins were depleted. Hence, there was a fairly weak linkage between bacterial community composition and DOC utilization suggesting that overall bacterioplankton community structure only to some extent has predictive power for processing of the DOC pool.

  • 252.
    Dinasquet, Julie
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Univ Copenhagen, Denmark ; Scripps Inst Oceanography, USA.
    Richert, Inga
    Uppsala University ; UFZ Helmholtz Ctr Environm Res, Germany.
    Logares, Ramiro
    CSIC, Spain.
    Yager, Patricia
    Univ Georgia, USA.
    Bertilsson, Stefan
    Uppsala University.
    Riemann, Lasse
    Univ Copenhagen, Denmark.
    Mixing of water masses caused by a drifting iceberg affects bacterial activity, community composition and substrate utilization capability in the Southern Ocean2017In: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 19, no 6, p. 2453-2467Article in journal (Refereed)
    Abstract [en]

    The number of icebergs produced from ice-shelf disintegration has increased over the past decade in Antarctica. These drifting icebergs mix the water column, influence stratification and nutrient condition, and can affect local productivity and food web composition. Data on whether icebergs affect bacterioplankton function and composition are scarce, however. We assessed the influence of iceberg drift on bacterial community composition and on their ability to exploit carbon substrates during summer in the coastal Southern Ocean. An elevated bacterial production and a different community composition were observed in iceberg-influenced waters relative to the undisturbed water column nearby. These major differences were confirmed in short-term incubations with bromodeoxyuridine followed by CARD-FISH. Furthermore, one-week bottle incubations amended with inorganic nutrients and carbon substrates (a mix of substrates, glutamine, Nacetylglucosamine, or pyruvate) revealed contrasting capacity of bacterioplankton to utilize specific carbon substrates in the iceberg-influenced waters compared with the undisturbed site. Our study demonstrates that the hydrographical perturbations introduced by a drifting iceberg can affect activity, composition, and substrate utilization capability of marine bacterioplankton. Consequently, in a context of global warming, increased frequency of drifting icebergs in polar regions holds the potential to affect carbon and nutrient biogeochemistry at local and possibly regional scales.

  • 253.
    Doane, Marie
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    An Environmental Risk Assessment of Four Common Footbaths Used by Dairy Farms in the United States2013Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
  • 254.
    Doane, Marie
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Modified C-BARQ and quality of life for both dog and owner. An embryo to a dog welfare assessment? 2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

     There is a need for further development of dog welfare assessments and the goal of this pilot study is the first step to such assessment.

     With the assumption that canine welfare consists of three major considerations, the dogs’ behaviour, the dogs’ quality of life (QoL dog) and the owners quality of life as pertaining to being a dog owner (QoL Owner). A questionnaire was constructed and tested. Included were three different parts, from reliable and validated sections of previous surveys, 1.) a modified C-BARQ, 2.) QoL for the dog, 3.) QoL owner. The survey included  demographics. 185 satisfactory answers were obtained through social media by dog owners in Sweden, Canada and USA. The study was statistically analysed, with principal component factor analysis, and rendered 13 extracted factors similar to the original questionnaires, suggesting that the construct is valid.  Eleven of the thirteen factors showed moderate internal consistency of Cronbach’s  alpha >0.7, the remaining two factors were relatively low with Cronbach’s  alpha >0.6. 

     Several significant  correlations between the extracted factors were found in this study. Quality of life as a dog owner (QoL owner) was significantly affected by stress caused by dogs displaying fear, excitability and separation anxiety. No significant  correlations were found between any factors describing  aggressive behaviors and the dogs QoL or QoL owner. Many significant correlations were found between the extracted factors and the demographics, for instance, the Swedes in this study are more active with their dogs compared to Americans and Canadians

     The results of this pilot study shows that it is possible to construct a reliable questionnaire from prior validated surveys. Further investigations should be commensed to validate the results in a larger population. Finally, a dog welfare  assessment could maybe be developed based on the questionnaire, to evaluate the individual dog’s risk for inferior quality of life.

  • 255.
    Doane, Marie
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Sarenbo, Sirkku
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    A modified combined C-BARQ and QoL for both the companion dog and its owner. An embryo to a companion dog welfare measurement?2019In: Applied Animal Behaviour Science, ISSN 0168-1591, E-ISSN 1872-9045, Vol. 213, p. 91-106Article in journal (Refereed)
    Abstract [en]

    The results of this pilot study demonstrate that it is possible to construct a reliable questionnaire from prior validated surveys. This questionnaire displays possible suitability for further development into a tool for a comprehensive dog welfare assessment. The welfare model used is assuming that canine welfare consists of three major considerations, the dogs’ behavior, the dogs’ quality of life (QoL dog) and the owner’s quality of life as pertaining to being a dog owner (QoL Owner). A questionnaire was constructed and tested. Three different parts from reliable and validated sections of previous surveys were included: 1) a modified C-BARQ, 2) QoL for the dog, and 3) QoL owner. 185 satisfactory answers were obtained from the respondents, dog owners in Sweden, Canada and USA. Principal component factor analysis rendered 13 extracted factors similar to the original questionnaires, suggesting that the construct is valid. Eleven of the thirteen factors showed moderate internal consistency of Cronbach’s alpha >0.7, the remaining two factors were relatively low with Cronbach’s alpha >0.6.

    Several significant correlations between the extracted factors were found. Quality of life as a dog owner (QoL owner) was significantly affected by stress caused by dogs displaying fear, excitability and separation anxiety. No significant correlations were found between any factors describing aggressive behaviors and the dogs QoL or QoL owner. Several significant correlations were found between the extracted factors and the demographics, for instance, the Swedes are more active with their dogs compared to Americans and Canadians. Further investigations should be commenced to validate the results in a larger population.

  • 256.
    Doane, Marie
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Sarenbo, Sirkku
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    An eradication attempt of Mycoplasma spp. mastitis at a large dairy farm in NY State, USA2015In: IOCH 2015, 2015Conference paper (Refereed)
  • 257.
    Doane, Marie
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Sarenbo, Sirkku
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Antibiotic usage in 2013 on a dairy CAFO in NY State, USA2014In: Infection Ecology & Epidemiology, ISSN 2000-8686, E-ISSN 2000-8686, Vol. 4, p. Articel ID: 24259-Article in journal (Refereed)
    Abstract [en]

    Antimicrobial resistance is threatening humans and animals worldwide. Biosecurity and 1-year usage of antibiotics on a dairy concentrated animal feeding operation (CAFO) in NY State, USA, were mapped: how much antibiotics were used, for what purpose, and whether any decrease could be warranted. Approximately 493 kg antibiotics was used, of which 376 kg was ionophores (monensin and lasalocides), 79 kg penicillin, 16.5 kg lincosamides, 8.0 kg aminoglycosides, 7.7 kg sulfamides, 3.4 kg cephalosporin, 2 kg macrolides, 0.7 kg amphenicols, and 0.1 kg fluoroquinolones. Usage reduction by 84% was realistic without compromising the animal welfare. Further reduction could be possible by improving the biosecurity and by utilizing antibiotic sensitivity testing.

  • 258.
    Doane, Marie
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Sarenbo, Sirkku
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Exposure of Farm Laborers and Dairy Cattle to Formaldehyde from Footbath Use at a Dairy Farm in New York State2014In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 487, p. 65-71Article in journal (Refereed)
    Abstract [en]

    Formalin footbaths are commonly used in the dairy industry to prevent cattle hoof diseases. Although formalin is a well-documented disinfectant, it is also a carcinogen and irritant. The aim of this study was to estimate the exposure of farm workers and dairy cattle to formaldehyde from footbaths located in a milking facility and a heifer facility at a dairy farm in western New York, USA. The dairy farm included approximately 3900 dairy cattle including young stock; of these, 1670 cows were milked three times per day in a 60-stall carousel milking parlor, and approximately 800 heifers were located at the heifer facility where footbaths with formalin were in use. The formaldehyde concentration of the air was measured using a Formaldemeter™ htV approximately 50 cm above the 3% formalin footbaths in the milking (one footbath location) and heifer (three footbath locations) facilities on three consecutive days. The measured formaldehyde concentrations varied between 0.00 and 2.28 ppm, falling within the safety guidelines established by the Occupation Safety and Health Administration (OSHA) of the United States. Significant differences were found in the formaldehyde concentrations at the different footbath locations in the heifer facility, potentially due to the varying levels of ventilation at each location. Changes in the ambient temperature during the 3-day sampling period did not significantly affect the concentrations. We believe that the substantial ventilation at both the heifer and milking facilities ensured that the formaldehyde concentrations did not exceed OSHA guidelines, thus permitting the safe use of formalin footbaths in this farm.

  • 259.
    Donadi, Serena
    et al.
    Swedish University of Agricultural Sciences, Sweden.
    Sandin, Leonard
    Swedish University of Agricultural Sciences, Sweden.
    Tamario, Carl
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Swedish University of Agricultural Sciences, Sweden.
    Degerman, Erik
    Swedish University of Agricultural Sciences, Sweden.
    Country-wide analysis of large wood as a driver of fish abundance in Swedish streams: Which species benefit and where?2019In: Aquatic conservation, ISSN 1052-7613, E-ISSN 1099-0755, Vol. 29, no 5, p. 706-716Article in journal (Refereed)
    Abstract [en]

    Rivers are heavily affected by human impacts that threaten many fish species. Among restoration measures, the addition of large wood (LW) in streams has been shown to increase fish abundance, yet which species benefit from LW, to what extent relative to other drivers, and which factors influence LW quantity is not clear, and these uncertainties limit our ability to use LW as an effective restoration measure. Here, a time series (from 1993 to 2016) of electrofishing data, including 3641 streams across Sweden, was used to investigate the beneficial effects of LW on the abundance of juvenile brown trout, Salmo trutta, juvenile Atlantic salmon, Salmo salar, and juvenile and adult sculpins, Cottus gobio and Cottus poecilopus, while accounting for other abiotic and biotic factors, and the drivers of LW abundance at a country-wide scale. Large wood benefitted brown trout, and the effects were greater with decreasing shaded stream surface. LW effects were comparable in magnitude to the positive effects of average annual air temperature and the negative effects of stream depth and predator abundance - factors where the influence was second only to the negative effects of stream width. LW did not benefit salmon abundance, which was correlated positively with stream width and negatively with altitude, nor did it benefit sculpin abundances, which mainly decreased with annual average air temperature and altitude. The quantity of LW strongly diminished with stream width, and, to a lesser extent, with stream depth, altitude, annual average air temperature, and forest age, whereas it increased with stream velocity, slope, and forest cover. The results suggest that LW can be used as an effective restoration tool for brown trout in shallow and narrow streams, especially in areas with little shade. Here, the addition of LW may help to alleviate the impacts of forest clearance and climate change.

  • 260.
    Dopson, Mark
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Physiological and phylogenetic diversity of acidophilic bacteria2016In: Acidophiles: life in extremely acidic environments / [ed] Quatrini R & Johnson DB, Caister Academic Press, 2016, p. 79-92Chapter in book (Refereed)
    Abstract [en]

    Acidophilic bacteria can be found in natural and anthropogenic acidic environments such as acid sulfate soils and biomining operations. These environments range in temperatures from below zero where low temperature adapted, acidophilic bacteria accelerate metal and acid release from sulfide minerals, through mesophilic environments, to hot solfataric fields containing Hydrogenobaculum acidophilum with a temperature optimum of 65°C. Acidophilic bacteria have been isolated from the ActinobacteriaAquificaeFirmicutesNitropsoraProteobacteria, and Verrucomicrobia phyla, and are capable of oxidizing both inorganic and organic electron donors coupled to the reduction of oxygen or ferric iron, though no extremely acidophilic bacteria are known to ferment organic substrates. Acidophilic bacteria also exhibit a range of carbon metabolisms, from obligate autotrophs such as Leptospirillum spp., facultative autotrophs such as Sulfobacillus spp. that can both fix carbon dioxide (CO2) or assimilate organic carbon, to obligate heterotrophs such as Alicyclobacillus tolerans. This chapter summarizes present knowledge of the physiological and phylogenetic diversity of acidophilic bacteria and highlights differences in growth characteristics between the various species.

  • 261.
    Dopson, Mark
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Holmes, David S
    Universidad Andres Bello, Santiago, Chile.
    Metal resistance in acidophilic microorganisms and its significance for biotechnologies.2014In: Applied Microbiology and Biotechnology, ISSN 0175-7598, E-ISSN 1432-0614, Vol. 98, no 19, p. 8133-8144Article in journal (Refereed)
    Abstract [en]

    Extremely acidophilic microorganisms have an optimal pH of <3 and are found in all three domains of life. As metals are more soluble at acid pH, acidophiles are often challenged by very high metal concentrations. Acidophiles are metal-tolerant by both intrinsic, passive mechanisms as well as active systems. Passive mechanisms include an internal positive membrane potential that creates a chemiosmotic gradient against which metal cations must move, as well as the formation of metal sulfate complexes reducing the concentration of the free metal ion. Active systems include efflux proteins that pump metals out of the cytoplasm and conversion of the metal to a less toxic form. Acidophiles are exploited in a number of biotechnologies including biomining for sulfide mineral dissolution, biosulfidogenesis to produce sulfide that can selectively precipitate metals from process streams, treatment of acid mine drainage, and bioremediation of acidic metal-contaminated milieux. This review describes how acidophilic microorganisms tolerate extremely high metal concentrations in biotechnological processes and identifies areas of future work that hold promise for improving the efficiency of these applications.

  • 262.
    Dopson, Mark
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Holmes, David S.
    Andrés Bello National University, Chile;Fundación Ciencia & Vida, Chile.
    Lazcano, Marcelo
    Andrés Bello National University, Chile;Fundación Ciencia & Vida, Chile.
    McCredden, Timothy J.
    Curtin University, Australia.
    Bryan, Christopher G.
    Curtin University, Australia.
    Mulroney, Kieran T.
    Curtin University, Australia.
    Steuart, Robert
    Curtin University, Australia.
    Jackaman, Connie
    Curtin University, Australia.
    Watkin, Elizabeth L. J.
    Curtin University, Australia.
    Multiple Osmotic Stress Responses in Acidihalobacter prosperus Result in Tolerance to Chloride Ions2017In: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 7, article id 2132Article in journal (Refereed)
    Abstract [en]

    Extremely acidophilic microorganisms (pH optima for growth of <= 3) are utilized for the extraction of metals from sulfide minerals in the industrial biotechnology of biomining. A long term goal for biomining has been development of microbial consortia able to withstand increased chloride concentrations for use in regions where freshwater is scarce. However, when challenged by elevated salt, acidophiles experience both osmotic stress and an acidification of the cytoplasm due to a collapse of the inside positive membrane potential, leading to an influx of protons. In this study, we tested the ability of the halotolerant acidophile Acidihalobacter prosperus to grow and catalyze sulfide mineral dissolution in elevated concentrations of salt and identified chloride tolerance mechanisms in Ac. prosperus as well as the chloride susceptible species, Acidithiobacillus ferrooxidans. Ac. prosperus had optimum iron oxidation at 20 g L-1 NaCl while At. ferrooxidans iron oxidation was inhibited in the presence of 6 g L-1 NaCl. The tolerance to chloride in Ac. prosperus was consistent with electron microscopy, determination of cell viability, and bioleaching capability. The Ac. prosperus proteomic response to elevated chloride concentrations included the production of osmotic stress regulators that potentially induced production of the compatible solute, ectoine uptake protein, and increased iron oxidation resulting in heightened electron flow to drive proton export by the F0F1 ATPase. In contrast, At. ferrooxidans responded to low levels of Cl- with a generalized stress response, decreased iron oxidation, and an increase in central carbon metabolism. One potential adaptation to high chloride in the Ac. prosperus Rus protein involved in ferrous iron oxidation was an increase in the negativity of the surface potential of Rus Form I (and Form II) that could help explain how it can be active under elevated chloride concentrations. These data have been used to create a model of chloride tolerance in the salt tolerant and susceptible species Ac. prosperus and At. ferrooxidans, respectively.

  • 263.
    Dopson, Mark
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Ni, Gaofeng
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Sleutels, Tom H. J. A.
    European Ctr Excellence Sustainable Water Technol, Netherlands.
    Possibilities for extremophilic microorganisms in microbial electrochemical systems2016In: FEMS Microbiology Reviews, ISSN 0168-6445, E-ISSN 1574-6976, Vol. 40, no 2, p. 164-181Article, review/survey (Refereed)
    Abstract [en]

    Microbial electrochemical systems exploit the metabolism of microorganisms to generate electrical energy or a useful product. In the past couple of decades, the application of microbial electrochemical systems has increased from the use of wastewaters to produce electricity to a versatile technology that can use numerous sources for the extraction of electrons on the one hand, while on the other hand these electrons can be used to serve an ever increasing number of functions. Extremophilic microorganisms grow in environments that are hostile to most forms of life and their utilization in microbial electrochemical systems has opened new possibilities to oxidize substrates in the anode and produce novel products in the cathode. For example, extremophiles can be used to oxidize sulfur compounds in acidic pH to remediate wastewaters, generate electrical energy from marine sediment microbial fuel cells at low temperatures, desalinate wastewaters and act as biosensors of low amounts of organic carbon. In this review, we will discuss the recent advances that have been made in using microbial catalysts under extreme conditions and show possible new routes that extremophilic microorganisms open for microbial electrochemical systems.This review highlights the use of microbial electrochemical systems to catalyze environmental processes coupled to the production of energy or valuable resources and how utilizing extremophilic microorganisms opens up new possibilities such as bioremediation of environmentally hazardous wastes.This review highlights the use of microbial electrochemical systems to catalyze environmental processes coupled to the production of energy or valuable resources and how utilizing extremophilic microorganisms opens up new possibilities such as bioremediation of environmentally hazardous wastes.

  • 264.
    Dopson, Mark
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Ossandon, Francisco J.
    Universidad Andrés Bello, Chile.
    Lovgren, Lars
    Umeå University.
    Holmes, David S.
    Universidad Andrés Bello, Chile.
    Metal resistance or tolerance?: Acidophiles confront high metal loads via both abiotic and biotic mechanisms2014In: Frontiers in Microbiology, ISSN 1664-302X, E-ISSN 1664-302X, Vol. 5, article id 157Article in journal (Refereed)
    Abstract [en]

    All metals are toxic at high concentrations and consequently their intracellular concentrations must be regulated. Extremely acidophilic microorganisms have an optimum growth of pH <3 and proliferate in natural and anthropogenic low pH environments. Some acidophiles are involved in the catalysis of sulfide mineral dissolution, resulting in high concentrations of metals in solution. Acidophiles are often described as highly metal resistant via mechanisms such as multiple and/or more efficient active resistance systems than are present in neutrophiles. However, this is not the case for all acidophiles and we contend that their growth in high metal concentrations is partially due to an intrinsic tolerance as a consequence of the environment in which they live. In this perspective, we highlight metal tolerance via complexation of free metals by sulfate ions and passive tolerance to metal influx via an internal positive cytoplasmic transmembrane potential. These tolerance mechanisms have been largely ignored in past studies of acidophile growth in the presence of metals and should be taken into account.

  • 265.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Heim, Christine
    Göttingen university, Germany.
    Hogmalm, Johan
    Göteborgs universitet.
    Hansen, Bent
    Göttingen university, Germany.
    Fracture zone-scale variation of trace elements and stable isotopes in calcite in a crystalline rock setting2014In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 40, p. 11-24Article in journal (Refereed)
    Abstract [en]

    With an aim to increase the understanding about the isotopic and chemical heterogeneity of calcites in water-conducting fracture zones with different crystalline wall rock compositions at different depths, we present trace element chemistry, isotopic composition (δ18O, δ13C, 87Sr/86Sr) and biomarkers of euhedral low-temperature fracture-coating calcite. Paleohydrogeological fluctuations and wall rock influence on the hydrochemistry in the deep groundwater are explored. Samples are from several fracture zone sub-fractures (at −360 to −740 m), retrieved during an extensive core drilling campaign in Sweden.

    Calcite generally showed fracture zone specific values of δ13C, δ18O and 87Sr/86Sr, which indicates precipitation from relatively homogeneous fluid (similar to the modern groundwater at the site) at the same event in each fracture zone. δ18O and δ13C in the different fracture zones were consistent with precipitation from waters of different salinity and decreasing organic input with depth, respectively. The latter is also supported by biomarkers showing clear indications of SRB-related organic compounds (e.g. iso- and anteiso-C17:0-branched fatty acids), except in the deepest zone. In contrast to the isotopes, variation in trace elements within the fracture zones was generally up to several orders of magnitude. Manganese and REE, as oppose to the other metals, were higher in the shallow fracture zones (112–1130 and 44–97 ppm, respectively) than in the deeper (28–272 and 5–11 ppm, respectively), in agreement with the groundwater composition. Although the rock types varied between and within the different fracture zones, this had insignificant influence on the trace element chemistry of the calcites. Co-variation was generally relatively large for many trace elements, with isometric logratio correlation generally better than 0.75, which indicates that their variation in the calcites is due to variation of Ca in the fracture water, but other local factors, especially uptake in co-precipitating minerals (clay minerals, barite, pyrite and zeolites), but also microbial activity and metal speciation may have influenced the metal incorporation into calcite. These detailed studies of fracture calcite are of importance for the understanding of variation in fluid chemistry and trace metal uptake in fracture zones, adding together with hydrochemical studies detailed information optimal for site characterisation.

  • 266.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Heim, Christine
    Georg August Univ, Germany.
    Roberts, Nick M. W.
    British Geol Survey, UK.
    Zack, Thomas
    University of Gothenburg.
    Tillberg, Mikael
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. University of Gothenburg.
    Broman, Curt
    Stockholm University.
    Ivarsson, Magnus
    Swedish Museum of Natural History.
    Whitehouse, Martin J.
    Swedish Museum of Natural History.
    Åström, Mats E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Isotopic evidence for microbial production and consumption of methane in the upper continental crust throughout the Phanerozoic eon2017In: Earth and Planetary Science Letters, ISSN 0012-821X, E-ISSN 1385-013X, Vol. 470, p. 108-118Article in journal (Refereed)
    Abstract [en]

    Microorganisms produce and consume methane in terrestrial surface environments, sea sediments and, as indicated by recent discoveries, in fractured crystalline bedrock. These processes in the crystalline bedrock remain, however, unexplored both in terms of mechanisms and spatiotemporal distribution. Here we have studied these processes via a multi-method approach including microscale analysis of the stable isotope compositions of calcite and pyrite precipitated in bedrock fractures in the upper crust (down to 1.7 km) at three sites on the Baltic Shield. Microbial processes have caused an intriguing variability of the carbon isotopes in the calcites at all sites, with delta C-13 spanning as much as -93.1 parts per thousand (related to anaerobic oxidation of methane) to +36.5 parts per thousand (related to methanogenesis). Spatiotemporal coupling between the stable isotope measurements and radiometric age determinations (micro-scale dating using new high spatial methods: LA-ICP-MS U-Pb for calcite and Rb-Sr for calcite and co-genetic adularia) enabled unprecedented direct timing constraints of the microbial processes to several periods throughout the Phanerozoic eon, dating back to Devonian times. These events have featured variable fluid salinities and temperatures as shown by fluid inclusions in the calcite; dominantly 70-85 degrees C brines in the Paleozoic and lower temperatures (<50-62 degrees C) and salinities in the Mesozoic. Preserved organic compounds, including plant signatures, within the calcite crystals mark the influence of organic matter in descending surficial fluids on the microbial processes in the fracture system, thus linking processes in the deep and surficial biosphere. These findings substantially extend the recognized temporal and spatial range for production and consumption of methane within the upper continental crust. (C) 2017 Elsevier B.V. All rights reserved.

  • 267.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Heim, Christine
    Whitehouse, Martin
    Broman, Curt
    Åström, Mats E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Episodic microbial methanogenesis, methane oxidation and sulfate reduction in deep granite fractures at Forsmark, Sweden2017In: 15TH WATER-ROCK INTERACTION INTERNATIONAL SYMPOSIUM, WRI-15 / [ed] Marques, JM Chambel, A, 2017, p. 702-705Conference paper (Refereed)
    Abstract [en]

    An extensive microanalytical isotope study of calcite and pyrite has been carried out in bedrock fractures at Forsmark, Sweden. The very large delta C-13(calcite)-variation of 103.4% V-PDB in total (-69.2 to +34.2%) evidences significant spatial and temporal variability in processes and carbon sources in the deep fracture system during the period when these minerals were formed (Phanerozoic). The substantial delta C-13(calcite)-span is mainly methane-related, with heavy and very light delta C-13 originating from ubiquitous in situ microbial methanogenesis and anaerobic oxidation of methane (AOM), respectively. Co-genetic cubic and framboidal pyrite showed substantial sulfate reducing bacteria (SRB)-related delta S-34 variation of 95% V-CDT overall (-29 to +66%), indicating closed system isotope distillation and point to similar genetic SRB methane-oxidizer relationships as in marine sediments. The depth distribution of the methanogenesis-, SRB- and AOM-signatures are from just below the ground surface down to about 800 m, which marks the deepest occurrence of AOM-related carbonate yet reported from the continental crystalline crust. Biomarkers and fluid inclusions suggest that the microbial activity in the bedrock fractures was closely related to descending surficial fluids and basinal brines rich in organic matter, in at least two pulses (70-80 degrees C and <50-62 degrees C). (C) 2017 Published by Elsevier B.V.

  • 268.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Ivarsson, Magnus
    University of Southern Denmark, Denmark.
    The role of anaerobic fungi in fundamental biogeochemical cycles in the deep biosphere2018In: Fungal Biology Reviews, ISSN 1749-4613, E-ISSN 1878-0253, Vol. 32, no 1, p. 20-25Article in journal (Refereed)
    Abstract [en]

    A major part of the biologic activity on Earth is hidden underneath our feet in an environment coined the deep biosphere which stretches several kilometers down into the bedrock. The knowledge about life in this vast energy-poor deep system is, however, extremely scarce, particularly for micro-eukaryotes such as fungi, as most studies have focused on prokaryotes. Recent findings suggest that anaerobic fungi indeed thrive at great depth in fractures and cavities of igneous rocks in both the oceanic and the continental crust. Here we discuss the potential importance of fungi in the deep biosphere, in particular their involvement in fundamental biogeochemical processes such as symbiotic relationships with prokaryotes that may have significant importance for the overall energy cycling within this vast subsurface realm. Due to severe oligotrophy, the prokaryotic metabolism at great depth in the crust is very slow and dominantly autotrophic and thus dependent on e.g. hydrogen gas, but the abiotic production of this gas is thought to be insufficient to fuel the deep autotrophic biosphere. Anaerobic fungi are heterotrophs that produce hydrogen gas in their metabolism and have therefore been put forward as a hypothetical provider of this substrate to the prokaryotes. Recent in situ findings of fungi and isotopic signatures within co-genetic sulfide minerals formed from bacterial sulfate reduction in the deep continental biosphere indeed seem to confirm the fungi-prokaryote hypothesis. This suggests that fungi play a fundamental biogeochemical role in the deep biosphere.

  • 269.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Ivarsson, Magnus
    Swedish Museum of Natural History.
    Bengtson, Stefan
    Swedish Museum of Natural History.
    Heim, Christine
    Georg-August University, Germany.
    Siljeström, Sandra
    SP Technical Research Institute of Sweden.
    Whitehouse, Martin J.
    Swedish Museum of Natural History.
    Broman, Curt
    Stockholm University.
    Belivanova, Veneta
    Swedish Museum of Natural History.
    Åström, Mats E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Anaerobic consortia of fungi and sulfate reducing bacteria in deep granite fractures2017In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 8, p. 1-9, article id 55Article in journal (Refereed)
    Abstract [en]

    The deep biosphere is one of the least understood ecosystems on Earth. Although most microbiological studies in this system have focused on prokaryotes and neglected microeukaryotes, recent discoveries have revealed existence of fossil and active fungi in marine sediments and sub-seafloor basalts, with proposed importance for the subsurface energy cycle. However, studies of fungi in deep continental crystalline rocks are surprisingly few. Consequently, the characteristics and processes of fungi and fungus-prokaryote interactions in this vast environment remain enigmatic. Here we report the first findings of partly organically preserved and partly mineralized fungi at great depth in fractured crystalline rock (−740 m). Based on environmental parameters and mineralogy the fungi are interpreted as anaerobic. Synchrotron-based techniques and stable isotope microanalysis confirm a coupling between the fungi and sulfate reducing bacteria. The cryptoendolithic fungi have significantly weathered neighboring zeolite crystals and thus have implications for storage of toxic wastes using zeolite barriers.

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  • 270.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Ivarsson, Magnus
    University of Southern Denmark, Denmark.
    Tillberg, Mikael
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Whitehouse, Martin
    Swedish Museum of Natural History.
    Kooijman, Ellen
    Swedish Museum of Natural History.
    Ancient Microbial Activity in Deep Hydraulically Conductive Fracture Zones within the Forsmark Target Area for Geological Nuclear Waste Disposal, Sweden2018In: Geosciences, E-ISSN 2076-3263, Vol. 8, no 6, article id 211Article in journal (Refereed)
    Abstract [en]

    Recent studies reveal that organisms from all three domains of life—Archaea, Bacteria, and even Eukarya—can thrive under energy-poor, dark, and anoxic conditions at large depths in the fractured crystalline continental crust. There is a need for an increased understanding of the processes and lifeforms in this vast realm, for example, regarding the spatiotemporal extent and variability of the different processes in the crust. Here, we present a study that set out to detect signs of ancient microbial life in the Forsmark area—the target area for deep geological nuclear waste disposal in Sweden. Stable isotope compositions were determined with high spatial resolution analyses within mineral coatings, and mineralized remains of putative microorganisms were studied in several deep water-conducting fracture zones (down to 663 m depth), from which hydrochemical and gas data exist. Large isotopic variabilities of δ13Ccalcite (−36.2 to +20.2‰ V-PDB) and δ34Spyrite (−11.7 to +37.8‰ V-CDT) disclose discrete periods of methanogenesis, and potentially, anaerobic oxidation of methane and related microbial sulfate reduction at several depth intervals. Dominant calcite–water disequilibrium of δ18O and 87Sr/86Sr precludes abundant recent precipitation. Instead, the mineral coatings largely reflect an ancient archive of episodic microbial processes in the fracture system, which, according to our microscale Rb–Sr dating of co-genetic adularia and calcite, date back to the mid-Paleozoic. Potential Quaternary precipitation exists mainly at ~400 m depth in one of the boreholes, where mineral–water compositions corresponded

  • 271.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Mathurin, Frédéric A.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Zack, Thomas
    University of Gothenburg.
    Schaefer, Thorsten
    Karlsruhe Inst Technol, Germany.
    Incorporation of trace elements into calcite precipitated from deep anoxic groundwater in fractured granitoid rocks2017In: 15TH WATER-ROCK INTERACTION INTERNATIONAL SYMPOSIUM, WRI-15 / [ed] Marques, JM Chambel, A, 2017, p. 841-844Conference paper (Refereed)
    Abstract [en]

    An extensive microanalytical study of calcite precipitated from groundwater flowing into boreholes at >400 m depth in the Aspo Hard Rock Laboratory, Sweden, has been carried out. Hydrochemical variations in packed-off sections, isolating water-conducting fractures intersected by two boreholes, were documented over a period of 17 years. The extraction of the borehole equipment revealed calcite precipitation on the equipment. This mineral material enabled unique assessment of uptake of different trace elements by calcite during precipitation from granitoid fracture groundwater, at anoxic, low-temperature (c.a 14 degrees C), and neutral (pH: 7.4-7.7) conditions, under variable salinity (Cl: 2500-7000 mg/L) prevailing at these depths. Temporal hydrochemical variations could be traced by detailed micro-analytical transects in the calcites and the influence of metal speciation and complexation on partitioning into calcite could be assessed (e.g. explaining unexpectedly low incorporation of REEs). The resulting environment-specific partition coefficients for a large number of metals are relevant in models of radionuclide retention around proposed deep nuclear waste repositories in this kind of environment, particularly because 1) elements such as REEs act as natural analogues to actinides, and 2) existing coefficients established in laboratory or in other natural environments cannot be unreservedly applied to conditions in deep crystalline rocks. (C) 2017 The Authors. Published by B.V.

  • 272.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Mathurin, Frédéric A.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Bur Rech Geol & Minieres, France.
    Zack, Thomas
    University of Gothenburg.
    Schäfer, Thorsten
    Karlsruhe Inst Technol, Germany;Friedrich Schiller Univ Jena, Germany.
    Roberts, Nick
    British Geol Survey, UK.
    Whitehouse, Martin
    Swedish Museum of Natural History.
    Karlsson, Andreas
    Swedish Museum of Natural History.
    Broman, Curt
    Stockholm university.
    Åström, Mats E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Incorporation of Metals into Calcite in a Deep Anoxic Granite Aquifer2018In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 52, no 2, p. 493-502Article in journal (Refereed)
    Abstract [en]

    Understanding metal scavenging by calcite in deep aquifers in granite is of importance for deciphering and modeling hydrochemical fluctuations and water–rock interaction in the upper crust and for retention mechanisms associated with underground repositories for toxic wastes. Metal scavenging into calcite has generally been established in the laboratory or in natural environments that cannot be unreservedly applied to conditions in deep crystalline rocks, an environment of broad interest for nuclear waste repositories. Here, we report a microanalytical study of calcite precipitated over a period of 17 years from anoxic, low-temperature (14 °C), neutral (pH: 7.4–7.7), and brackish (Cl: 1700–7100 mg/L) groundwater flowing in fractures at >400 m depth in granite rock. This enabled assessment of the trace metal uptake by calcite under these deep-seated conditions. Aquatic speciation modeling was carried out to assess influence of metal complexation on the partitioning into calcite. The resulting environment-specific partition coefficients were for several divalent ions in line with values obtained in controlled laboratory experiments, whereas for several other ions they differed substantially. High absolute uptake of rare earth elements and U(IV) suggests that coprecipitation into calcite can be an important sink for these metals and analogousactinides in the vicinity of geological repositories.

  • 273.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Roberts, Nick M. W.
    British Geol Survey, UK.
    Heim, Christine
    Georg August Univ, Germany.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Sweden.
    Siljeström, Sandra
    RISE, Sweden.
    Kooijman, Ellen
    Swedish Museum of Natural History, Sweden.
    Broman, Curt
    Stockholm University, Sweden.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Sweden;Univ Southern Denmark, Denmark.
    Åström, Mats E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Timing and origin of natural gas accumulation in the Siljan impact structure, Sweden2019In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 10, p. 1-14, article id 4736Article in journal (Refereed)
    Abstract [en]

    Fractured rocks of impact craters may be suitable hosts for deep microbial communities on Earth and potentially other terrestrial planets, yet direct evidence remains elusive. Here, we present a study of the largest crater of Europe, the Devonian Siljan structure, showing that impact structures can be important unexplored hosts for long-term deep microbial activity. Secondary carbonate minerals dated to 80 +/- 5 to 22 +/- 3 million years, and thus postdating the impact by more than 300 million years, have isotopic signatures revealing both microbial methanogenesis and anaerobic oxidation of methane in the bedrock. Hydrocarbons mobilized from matured shale source rocks were utilized by subsurface microorganisms, leading to accumulation of microbial methane mixed with a thermogenic and possibly a minor abiotic gas fraction beneath a sedimentary cap rock at the crater rim. These new insights into crater hosted gas accumulation and microbial activity have implications for understanding the astrobiological consequences of impacts.

  • 274.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Roberts, Nick
    British Geological Survey, UK.
    Whitehouse, Martin
    Swedish Museum of Natural History, Sweden.
    Geochronology and Stable Isotope Analysis of Fracture-fill and Karst Mineralization Reveal Sub-Surface Paleo-Fluid Flow and Microbial Activity of the COSC-1 Borehole, Scandinavian Caledonides2020In: Geosciences, E-ISSN 2076-3263, Vol. 10, no 2, p. 1-17, article id 56Article in journal (Refereed)
    Abstract [en]

    The deep biosphere hosted in fractured rocks within the upper continental crust is one of the least understood and studied ecological realms on Earth. Scarce knowledge of ancient life and paleo-fluid flow within this realm is owing to the lack of deep drilling into the crust. Here we apply microscale high spatial-resolution analytical techniques to fine-grained secondary minerals in a deep borehole (COSC-1) drilled into the Silurian-Devonian Scandinavian Caledonide mountain range in central Sweden. The aim is to detect and date signs of ancient microbial activity and low-temperature fluid circulation in micro-karsts (foliation-parallel dissolution cavities in the rock) and fractures at depth in the nappe system. Vein carbonates sampled at 684 to 2210 m show a decreased C isotope variability at depths below 1050 m; likely due to decreased influence of organic-C at great depth. Micro-karsts at 122–178 m depth feature at least two generations of secondary calcite and pyrite growth in the voids as shown by secondary ion mass spectrometry analytical transects within individual grains. The younger of these two precipitation phases shows 34S-depleted δ34Spyrite values (−19.8 ± 1.6‰ vs Vienna-Canyon Diablo Troilite (V-CDT)) suggesting microbial sulfate reduction in situ. The calcite of this late phase can be distinguished from the older calcite by higher δ18Ocalcite values that correspond to precipitation from ambient meteoric water. The late stage calcite gave two separate laser ablation inductively coupled mass spectrometry-derived U-Pb ages (9.6 ± 1.3 Ma and 2.5 ± 0.2 Ma), marking a minimum age for widespread micro-karst formation within the nappe. Several stages of fluid flow and mineral precipitation followed karst formation; with related bacterial activity as late as the Neogene-Quaternary; in structures presently water conducting. The results show that our combined high spatial-resolution stable isotope and geochronology approach is suitable for characterizing paleo-fluid flow in micro-karst; in this case, of the crystalline crust comprising orogenic nappe units.

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  • 275.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Suksi, Juhani
    University of Helsinki, Finland.
    Tullborg, Eva-Lena
    Terralog AB.
    Lahaye, Yann
    Geological Survey of Finland, Finland.
    Quaternary redox transitions in deep crystalline rock fractures at the western margin of the Greenland ice sheet2017In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 76, p. 196-209Article in journal (Refereed)
    Abstract [en]

    When planning for long term deep geological repositories for spent nuclear fuel knowledge of processes that will influence and change the sub-surface environment is crucial. For repositories in northern Europe and similar areas, influence from advancing and retreating continental ice sheets must be planned for. Rapid transport of meltwater into the bedrock may introduce oxic conditions at great depth, which may affect the copper canisters planned to encapsulate the spent fuel. The lack of direct observations has led to simplified modelling assumptions not reflecting the complexity of natural systems. As part of a unique field and modelling study, The Greenland Analogue Project, of a continental ice sheet and related sub-surface conditions, we here present mineralogical and U-series data unravelling the Quaternary redox history in the deep bedrock fracture system close to the margin of the Greenland ice sheet. The aim was to increase the understanding of circulation of potentially oxygenated glacial meltwater from the surface down to 650 m depth. Secondary mineral coatings were sampled from open fractures in cored boreholes down to 650 m, within and below the current permafrost. Despite continental ice sheet coverage and/or prevailing permafrost during large parts of the last 1 Ma, measured disequilibrium in the U-238-U-234-Th-230 system shows that water has circulated in the bedrock fracture system at various occasions during this time span. In fractures of the upper 60 m, infiltration of oxygenated surface water has resulted in a prominent near-surface "oxidised zone" with abundant FeOOH precipitation. However, this zone must be relict because it is currently within permafrost and the U-series disequilibrium signatures of most fracture coatings show evidence of deposition of U prior to the Holocene and even prior to the last glaciation maximum which occurred less than 100 ka ago. This U deposition is found both within and below the near surface "oxidised zone" indicating temporal redox variation within this zone during the last 1 Ma. Potential Holocene leaching of U is indicated by Th-230/U-238 >> 1 and close to secular equilibrium for U-234/U-238 in some of the near surface fractures and also in a couple of deeper fractures. Indicated U-leaching in the talik within the last 200 ka is proposed to be the result of talik-related discharge of water with a capability of keeping U in solution. Circulation of oxidative water in the deep system beneath the permafrost is indicated only in a few fractures and solely by U-series disequilibrium (Th-230/U-238 activity ratios up to 2.97 at 431 m depth), probably due to restricted, perhaps sporadic infiltration of oxidative water, potentially during the Holocene. In these fractures, the conditions have in general been more reducing than in the near surface system where oxidising conditions have prevailed and penetration of oxygenated waters may have been continuous. (C) 2016 Elsevier Ltd. All rights reserved.

  • 276.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tullborg, Eva-Lena
    University of Gothenburg.
    Whitehouse, Martin
    Swedish Museum of Natural History.
    Sandberg, Bertil
    Swerea KIMAB, Sweden.
    Blomfeldt, Thomas
    Swerea KIMAB, Sweden.
    Åström, Mats E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Extreme fractionation and micro-scale variation of sulphur isotopes during bacterial sulphate reduction in deep groundwater systems2015In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 161, p. 1-18Article in journal (Refereed)
    Abstract [en]

    This study conducted at the Aspo Hard Rock Laboratory, SE Sweden, determines the extent and mechanisms of sulphur-isotope fractionation in permanently reducing groundwater in fractured crystalline rock. Two boreholes > 400 m below the ground surface were investigated. In the 17-year-old boreholes, the Al instrumentation pipes had corroded locally (i.e., Al[oxy] hydroxides had formed) and minerals (i.e., pyrite, iron monosulphide, and calcite) had precipitated on various parts on the equipment. By chemically and isotopically comparing the precipitates on the withdrawn instrumentation and the borehole waters, we gained new insight into the dynamics of sulphate reduction, sulphide precipitation, and sulphur-isotope fractionation in deep-seated crystalline-rock settings. An astonishing feature of the pyrite is its huge variability in delta S-34, which can exceed 100 parts per thousand in total (i.e., -47.2 to +53.3 parts per thousand) and 60 parts per thousand over 50 mu m of growth in a single crystal. The values at the low end of the range are up to 71 parts per thousand lower than measured in the dissolved sulphate in the water (20-30 parts per thousand), which is larger than the maximum difference reported between sulphate and sulphide in pure-culture experiments (66 parts per thousand) but within the range reported from natural sedimentary settings. Although single-step reduction seems likely, further studies are needed to rule out the effects of possible S disproportionation. The values at the high end of the range (i.e., high delta S-34(py)) are much higher than could be produced from the measured sulphate under any biogeochemical conditions. This strongly suggests the development of closed-system conditions near the growing pyrite, i.e., the rate of sulphate reduction exceeds the rate of sulphate diffusion in the local fluid near the pyrite, causing the local aqueous phase (and thus the forming pyrite) to become successively enriched in heavy S (S-34). Consequently, the delta S-34 values of the forming pyrite become exceptionally high and strongly decoupled from the delta S-34 values of the sulphate in the bulk fluid. The Al-(oxy) hydroxide and calcite precipitates are explained by a combination of deposit and galvanic corrosion initiated by Al corrosion by H2S produced by sulphate-reducing microorganisms. (C) 2015 Elsevier Ltd. All rights reserved.

  • 277.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Whitehouse, Martin J.
    Swedish Museum of Natural History.
    Heim, Christine
    Georg August Univ, Germany.
    Reiners, Peter W.
    Univ Arizona, USA.
    Tillberg, Mikael
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Hogmalm, K. Johan
    University of Gothenburg.
    Dopson, Mark
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Broman, Curt
    Stockholm University.
    Åström, Mats E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Unprecedented 34S-enrichment of pyrite formed following microbial sulfate reduction in fractured crystalline rocks2018In: Geobiology, ISSN 1472-4677, E-ISSN 1472-4669, Vol. 16, no 5, p. 556-574Article in journal (Refereed)
    Abstract [en]

    In the deep biosphere, microbial sulfate reduction (MSR) is exploited for energy. Here, we show that, in fractured continental crystalline bedrock in three areas in Sweden, this process produced sulfide that reacted with iron to form pyrite extremely enriched in S-34 relative to S-32. As documented by secondary ion mass spectrometry (SIMS) microanalyses, the S-34(pyrite) values are up to +132 parts per thousand V-CDT and with a total range of 186 parts per thousand. The lightest S-34(pyrite) values (-54 parts per thousand) suggest very large fractionation during MSR from an initial sulfate with S-34 values (S-34(sulfate,0)) of +14 to +28 parts per thousand. Fractionation of this magnitude requires a slow MSR rate, a feature we attribute to nutrient and electron donor shortage as well as initial sulfate abundance. The superheavy S-34(pyrite) values were produced by Rayleigh fractionation effects in a diminishing sulfate pool. Large volumes of pyrite with superheavy values (+120 +/- 15 parts per thousand) within single fracture intercepts in the boreholes, associated heavy average values up to +75 parts per thousand and heavy minimum S-34(pyrite) values, suggest isolation of significant amounts of isotopically light sulfide in other parts of the fracture system. Large fracture-specific S-34(pyrite) variability and overall average S-34(pyrite) values (+11 to +16 parts per thousand) lower than the anticipated S-34(sulfate,0) support this hypothesis. The superheavy pyrite found locally in the borehole intercepts thus represents a late stage in a much larger fracture system undergoing Rayleigh fractionation. Microscale Rb-Sr dating and U/Th-He dating of cogenetic minerals reveal that most pyrite formed in the early Paleozoic era, but crystal overgrowths may be significantly younger. The C-13 values in cogenetic calcite suggest that the superheavy S-34(pyrite) values are related to organotrophic MSR, in contrast to findings from marine sediments where superheavy pyrite has been proposed to be linked to anaerobic oxidation of methane. The findings provide new insights into MSR-related S-isotope systematics, particularly regarding formation of large fractions of S-34-rich pyrite.

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  • 278.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Åström, Mats E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Heim, Christine
    Univ Göttingen, Germany.
    Broman, Curt
    Stockholm University.
    Åstrom, Jan
    CSC IT Ctr Sci, Finland.
    Whitehouse, Martin
    Swedish Museum of Natural History.
    Ivarsson, Magnus
    Swedish Museum of Natural History.
    Siljeström, Sandra
    SP Tech Res Inst Sweden.
    Sjövall, Peter
    SP Tech Res Inst Sweden.
    Extreme C-13 depletion of carbonates formed during oxidation of biogenic methane in fractured granite2015In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 6, article id 7020Article in journal (Refereed)
    Abstract [en]

    Precipitation of exceptionally C-13-depleted authigenic carbonate is a result of, and thus a tracer for, sulphate-dependent anaerobic methane oxidation, particularly in marine sediments. Although these carbonates typically are less depleted in C-13 than in the source methane, because of incorporation of C also from other sources, they are far more depleted in C-13 (delta C-13 as light as - 69% V-PDB) than in carbonates formed where no methane is involved. Here we show that oxidation of biogenic methane in carbon-poor deep groundwater in fractured granitoid rocks has resulted in fracture-wall precipitation of the most extremely C-13-depleted carbonates ever reported, delta C-13 down to - 125% V-PDB. A microbial consortium of sulphate reducers and methane oxidizers has been involved, as revealed by biomarker signatures in the carbonates and S-isotope compositions of co-genetic sulphide. Methane formed at shallow depths has been oxidized at several hundred metres depth at the transition to a deep-seated sulphate-rich saline water. This process is so far an unrecognized terrestrial sink of methane.

  • 279.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Åström, Mats E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tullborg, Eva-Lena
    Göteborgs universitet.
    Whitehouse, Martin
    Naturhistoriska riksmuseet.
    Activity of sulfur reducing bacteria in deep bedrock fractures revealed by variability of δ34S in pyrite and dissolved sulphate2013In: Procedia Earth and Planetary Science, E-ISSN 1878-5220, Vol. 7, p. 228-231Article in journal (Refereed)
    Abstract [en]

    Euhedral pyrite crystals coating 46 granite fractures at depths down to nearly 1 km at Laxemar, Sweden, were analysed for sulfur isotopes (δ34Spyr) by in situ SIMS (secondary ion mass spectrometry) analysis. Most of these fractures had corresponding chemical and isotopic groundwater data, providing a unique opportunity of pyrite-sulfate comparison within the same fracture network. Comparison of the isotopic ratios (δ18O, δ13C, 87Sr/86Sr) of co-genetic calcite with the groundwater showed that the sampled fractures carried pyrite and calcite that are of low-temperature origin, and with some exceptions, possibly precipitated from the present groundwater, or similar pre-modern fluids.

    The δ34Spyr showed huge variations across individual crystals (such as -32 to +73‰) and an extreme overall range (-50‰ to +91‰), which can only be explained by the activity of sulfur reducing bacteria (SRB). The most common sub-grain features were an increase in δ34Spyr with crystal growth related to successively higher δ34SSO4 caused by ongoing SRB activity and Rayleigh fractionation in fractures with low flow. The groundwater δ34SSO4 values (+9 to +37‰) are, in particular in the sulfate-poor waters down to -400 m, higher than the anticipated initial values, and this can also be explained by SRB-related Rayleigh distillation. The δ34SSO4 of the groundwater is, however, lower than that required to produce the highest δ34Spyr values, which may be due to the signal of groundwater in low-flow fractures (carrying 34S-rich sulfate and pyrite) being masked in the water data by high-flow parts of the water-flowing structure carrying abundant and less fractionated sulfate.

  • 280.
    Drake, Henrik
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Åström, Mats E.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Tullborg, Eva-Lena
    Whitehouse, Martin
    Fallick, Anthony E.
    Variability of sulphur isotope ratios in pyrite and dissolved sulphate in granitoid fractures down to 1km depth - Evidence for widespread activity of sulphur reducing bacteria2013In: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 102, p. 143-161Article in journal (Refereed)
    Abstract [en]

    Euhedral pyrite crystals in 46 open bedrock (granitoid) fractures at depths down to nearly 1 km were analysed for sulphur isotope ratios (delta S-34) by the in situ secondary ion mass spectrometry (SIMS) technique and by conventional bulk-grain analysis, and were compared with groundwater data. Twenty nine of the fractures sampled for pyrite had corresponding data for groundwater, including chemistry and isotopic ratios of sulphate, which provided a unique opportunity to compare the sulphur-isotopic ratios of pyrite and dissolved sulphate both at site and fracture-specific scales. Assessment of pyrite age and formation conditions were based on the geological evolution of the area (Laxemar, SE Sweden), and on data on co-genetic calcite as follows: (1) the isotopic ratios of the calcite crystals (delta O-18, delta C-13, Sr-87/Sr-86) were compared with previously defined isotopic features of fracture mineral assemblages precipitated during various geological periods, and (2) the delta O-18 of the calcites were compared with the delta O-18 of groundwater in fractures corresponding to those where the calcite/pyrite assemblages were sampled. Taken together, the data show that all the sampled fractures carried pyrite/calcite that are low-temperature and precipitated from the current groundwater or similar pre-existing groundwater, except at depths of -300 to -600 m where water with a glacial component dominates and the crystals are from pre-modern fluids. An age of <10 Ma are anticipated for the pre-modern fluids. The delta S-34(pyr) showed huge variations across individual crystals (such as -32 to +73 parts per thousand) and extreme minimum (-50 parts per thousand) and maximum (+91 parts per thousand) values. For this kind of extreme S-isotopic variation at earth-surface conditions there is no other explanation than activity of sulphur reducing bacteria coupled with sulphate-limited conditions. Indeed, the most common subgrain feature was an increase in delta S-34(pyr) values from interior to rim of the crystal, which we interpret are related to successively higher delta S-34 values of the dissolved source SO42- caused by ongoing bacterial sulphate reduction in fractures with low-flow or stagnant waters. The measured groundwater had delta S-34(SO4) values of +9 parts per thousand to +37 parts per thousand, with the highest values associated with low sulphate concentrations. These values are overall, and especially in the sulphate-poor waters down to -400 m, somewhat higher than the anticipated initial values, and can thus, like for the S-34-enriched pyrites, be explained by a Rayleigh distillation process driven by microbial sulphate reduction. An intriguing feature was that the delta S-34(SO4) values of the groundwater were in no case reaching up to the values required to produce biogenic pyrite with delta S-34 values of +40 parts per thousand to +91 parts per thousand. To explain this feature, we suggest that groundwater in low-flow fractures with near-stagnant water (carrying sulphate and pyrite with high delta S-34) is masked by high-flow parts of the fracture system carrying groundwater that often contains sulphate in abundance and considerably less fractionated with respect to S-34 and S-32. In order to gain detailed knowledge of chemical processes and patterns in groundwater in fractured rock, fracture-mineral investigations are a powerful tool, as we have shown here for the sulphur system. (C) 2012 Elsevier Ltd. All rights reserved.

  • 281.
    Dunaj, Justyna
    et al.
    Medical University of Białystok, Poland.
    Moniuszko-Malinowska, Anna
    Medical University of Białystok, Poland.
    Swiecicka, Izabela
    University of Białystok, Poland.
    Andersson, Martin O.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Czupryna, Piotr
    Medical University of Białystok, Poland.
    Rutkowski, Krzysztof
    Guy’s and St Thomas’ NHS Foundation Trust, UK.
    Zambrowski, Grzegorz
    University of Białystok, Poland.
    Zajkowska, Joanna
    Medical University of Białystok, Poland.
    Grygorczuk, Sambor
    Medical University of Białystok, Poland.
    Kondrusik, Maciej
    Medical University of Białystok, Poland.
    Świerzbińska, Renata
    Medical University of Białystok, Poland.
    Pancewicz, Sławomir
    Medical University of Białystok, Poland.
    Tick-borne infections and co-infections in patients with non-specific symptoms in Poland2018In: Advances in Medical Sciences, ISSN 1896-1126, E-ISSN 1898-4002, Vol. 63, no 1, p. 167-172Article in journal (Refereed)
    Abstract [en]

    AIM: The aim of the study was the evaluation of the frequency of infections and co-infections among patients hospitalized because of non-specific symptoms after a tick bite.

    MATERIALS AND METHODS: Whole blood, serum and cerebrospinal fluid samples from 118 patients hospitalised for non-specific symptoms up to 8 weeks after tick bite from 2010 to 2013 were examined for tick-borne infections. ELISA, Western blot and/or molecular biology (PCR; fla gene; 16S rRNA; sequencing) and thin blood smears (MDD) were used. Control group included 50 healthy blood donors. All controls were tested with PCR and serology according to the same procedure as in patients.

    RESULTS: Out of 118 patients 85 (72%) experienced headaches, 15 (13%) vertigo, 32 (27%) nausea, 17 (14%) vomiting, 37 (31%) muscle pain, 73 (62%) fever and 26 (22%) meningeal signs. 47.5% were infected with at least one tick-borne pathogen. Borrelia burgdorferi sensu lato infection was confirmed with ELISA, Western blot in serum and/or (PCR (fla gene) in whole blood in 29.7% cases. In blood of 11.9% patients Anaplasma phagocytophilum DNA (16S rRNA gene) was detected; in 0.9% patients 1/118 Babesia spp. DNA (18S rRNA gene) was also detected. Co-infections were observed in 5.1% of patients with non-specific symptoms. B. burgdorferi s.l. - A. phagocytophilum co-infection (5/118; 4.2%) was most common. In 1/118 (0.8%) A. phagocytophilum - Babesia spp. co-infection was detected. All controls were negative for examined pathogens.

    CONCLUSIONS: Non-specific symptoms after tick bite may be caused by uncommon pathogens or co-infection, therefore it should be considered in differential diagnosis after tick bite.

  • 282.
    Dupont, Chris L.
    et al.
    J. Craig Venter Institute, USA.
    Larsson, John
    Stockholm University.
    Yooseph, Shibu
    J. Craig Venter Institute, USA.
    Ininbergs, Karolina
    Stockholm University.
    Goll, Johannes
    J. Craig Venter Institute, USA.
    Asplund-Samuelsson, Johannes
    Stockholm University.
    McCrow, John P.
    J. Craig Venter Institute, USA.
    Celepli, Narin
    Stockholm University.
    Allen, Lisa Zeigler
    J. Craig Venter Institute, USA.
    Ekman, Martin
    Stockholm University.
    Lucas, Andrew J.
    Hagström, Åke
    University of Gothenburg.
    Thiagarajan, Mathangi
    Brindefalk, Bjorn
    Richter, Alexander R.
    Andersson, Anders F.
    Tenney, Aaron
    Lundin, Daniel
    KTH Royal Institute of Technology.
    Tovchigrechko, Andrey
    Nylander, Johan A. A.
    Brami, Daniel
    Badger, Jonathan H.
    Allen, Andrew E.
    Rusch, Douglas B.
    Hoffman, Jeff
    Norrby, Erling
    Friedman, Robert
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Venter, J. Craig
    Bergman, Birgitta
    Functional Tradeoffs Underpin Salinity-Driven Divergence in Microbial Community Composition2014In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 9, no 2, article id e89549Article in journal (Refereed)
    Abstract [en]

    Bacterial community composition and functional potential change subtly across gradients in the surface ocean. In contrast, while there are significant phylogenetic divergences between communities from freshwater and marine habitats, the underlying mechanisms to this phylogenetic structuring yet remain unknown. We hypothesized that the functional potential of natural bacterial communities is linked to this striking divide between microbiomes. To test this hypothesis, metagenomic sequencing of microbial communities along a 1,800 km transect in the Baltic Sea area, encompassing a continuous natural salinity gradient from limnic to fully marine conditions, was explored. Multivariate statistical analyses showed that salinity is the main determinant of dramatic changes in microbial community composition, but also of large scale changes in core metabolic functions of bacteria. Strikingly, genetically and metabolically different pathways for key metabolic processes, such as respiration, biosynthesis of quinones and isoprenoids, glycolysis and osmolyte transport, were differentially abundant at high and low salinities. These shifts in functional capacities were observed at multiple taxonomic levels and within dominant bacterial phyla, while bacteria, such as SAR11, were able to adapt to the entire salinity gradient. We propose that the large differences in central metabolism required at high and low salinities dictate the striking divide between freshwater and marine microbiomes, and that the ability to inhabit different salinity regimes evolved early during bacterial phylogenetic differentiation. These findings significantly advance our understanding of microbial distributions and stress the need to incorporate salinity in future climate change models that predict increased levels of precipitation and a reduction in salinity.

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  • 283.
    Durjava, Mojca Kos
    et al.
    Publ Hlth Inst Maribor, Slovenia.
    Kolar, Boris
    Publ Hlth Inst Maribor, Slovenia.
    Arnus, Lovro
    Publ Hlth Inst Maribor, Slovenia.
    Papa, Ester
    Univ Insubria, Italy.
    Kovarich, Simona
    Univ Insubria, Italy.
    Sahlin, Ullrika
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Peijnenburg, Willie
    Natl Inst Publ Hlth & Environm RIVM, Netherlands ; Leiden Univ, Netherlands.
    Experimental Assessment of the Environmental Fate and Effects of Triazoles and Benzotriazole2013In: ATLA (Alternatives to Laboratory Animals), ISSN 0261-1929, Vol. 41, no 1, p. 65-75Article in journal (Refereed)
    Abstract [en]

    The environmental fate and effects of triazoles and benzotriazoles are of concern within the context of chemical regulation. As part of an intelligent testing strategy, experimental tests were performed on endpoints that are relevant for risk assessment. The experimental tests included the assessment of eco-toxicity to an alga, a daphnid and zebrafish embryos, and the assessment of ready biodegradability. Triazole and benzotriazole compounds were selected for testing, based on existing toxicity data for vertebrate and invertebrate species, as well as on the principal component analysis of molecular descriptors aimed at selecting the minimum number of test compounds in order to maximise the chemical domain spanned for both compound classes. The experimental results show that variation in the toxicities of triazoles and benzotriazole across species was relatively minor; in general, the largest factor was approximately 20. The study conducted indicated that triazoles are not readily biodegradable.

  • 284.
    Edfors, Inger
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Johansson-Cederblad, Brita
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Wikman, Susanne
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Linder, Cedric
    Uppsala universitet.
    Fokusgrupper avslöjar representationersmöjligheter och begränsningar för lärande i naturvetenskap2013Conference paper (Other academic)
  • 285.
    Edfors, Inger
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Wikman, Susanne
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Johansson-Cederblad, Brita
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Linder, Cedric
    Uppsala University.
    University students' reflections on representations in genetics and stereochemistry revealed by a focus group approach2015In: NorDiNa: Nordic Studies in Science Education, ISSN 1504-4556, E-ISSN 1894-1257, Vol. 11, no 2, p. 169-179Article in journal (Refereed)
    Abstract [en]

    Genetics and organic chemistry are areas of science that students regard as difficult to learn. Part ofthis difficulty is derived from the disciplines having representations as part of their discourses. In orderto optimally support students’ meaning-making, teachers need to use representations to structure themeaning-making experience in thoughtful ways that consider the variation in students’ prior knowledge.Using a focus group setting, we explored 43 university students’ reasoning on representationsin introductory chemistry and genetics courses. Our analysis of eight focus group discussions revealedhow students can construct somewhat bewildered relations with disciplinary-specific representations.The students stated that they preferred familiar representations, but without asserting themeaning-making affordances of those representations. Also, the students were highly aware of the affordances of certain representations, but nonetheless chose not to use those representations in theirproblem solving. We suggest that an effective representation is one that, to some degree, is familiarto the students, but at the same time is challenging and not too closely related to “the usual one”.The focus group discussions led the students to become more aware of their own and others ways ofinterpreting different representations. Furthermore, feedback from the students’ focus group discussionsenhanced the teachers’ awareness of the students’ prior knowledge and limitations in students’representational literacy. Consequently, we posit that a focus group setting can be used in a universitycontext to promote both student meaning-making and teacher professional development in a fruitfulway.

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  • 286.
    Edfors, Inger
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Wikman, Susanne
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Johansson-Cederblad, Brita
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Linder, Cedric
    Uppsala Universitet.
    University students' reflections on representations in introductory genetics and stereochemistry2014Conference paper (Other academic)
    Abstract [en]

    Genetics and organic chemistry are areas of science that are regarded as difficult. Part of thisdifficulty is derived from them having representations as part of their disciplinary discourses. Inorder to optimally support students’ learning and meaning-making, teachers need to thoughtfullyuse representations to structure the learning experience in ways that open up the variation instudents’ prior knowledge. For our study, university students’ reasoning on representations ingenetics and organic chemistry was investigated using a focus group approach (8 groups, 4-8students/group). This revealed how students can construct somewhat bewildered relations withdisciplinary-specific representations. For instance, they stated that they preferred familiarrepresentations, but without asserting the meaning-making affordances of those representations.Also, the students were highly aware of the affordances in certain representations, but nonethelesschose not to use those representations in their problem solving. The focus group discussions ledthe students to become more aware of their own and others meaning-making. At the same time,feedback from the students’ focus group discussions enhanced the teacher’s awareness of thestudents’ prior knowledge and meaning-making. Consequently, we posit that a design focus groupmethodology can be fruitfully used both to promote teacher development and progression, andstudent learning.

  • 287.
    Eihe, Paula
    et al.
    Latvia University of Life Sciences and Technologies, Latvia.
    Vebere, Lasma Lucija
    Latvia University of Life Sciences and Technologies, Latvia.
    Grinfelde, Inga
    Latvia University of Life Sciences and Technologies, Latvia;Scientific Laboratory of Forest and Water Resources, Latvia.
    Pilecka, Jovita
    Latvia University of Life Sciences and Technologies, Latvia;Scientific Laboratory of Forest and Water Resources, Latvia.
    Sachpazidou, Varvara
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Grinberga, Linda
    Latvia University of Life Sciences and Technologies, Latvia.
    The effect of acidification of pig slurry digestate applied on winter rapeseed on the ammonia emission reduction2019In: XVI-th International youth Science and Environmental Baltic Region Countries Forum 7–9 October 2019, Gdansk, Poland, Institute of Physics (IOP), 2019, Vol. 390, no 1, p. 1-6, article id 012043Conference paper (Refereed)
    Abstract [en]

    The Agriculture is the main source of ammonia emissions. It generates around 75% of global emissions of ammonia to the atmosphere and soil fertilisation accounts for half of agricultural emissions. Ammonia emissions have a negative impact on ecosystems and human health, as it is able to accumulate both as solid particles and as an integral part of acid cases. Measures to reduce ammonia emissions can be divided into three large groups: the first group is ammonia-reducing measures in animal housing, the second group is ammonia-reducing measures during manure storage, and the third group is ammonia-reducing measures during the application of manure. Measurements of ammonia emissions were carried out in the parish of Jaunberze, which took place on 30 April and 1 May 2018. Sulphuric acid was used for acidification of pig slurry digestate. Picarro G2508 was used for on field measurement of ammonia concentrations with 1 second interval, a measurement time of one session was 400 seconds. The volume of the chamber was 60 l and was connected to the Picarro G2508 using a 10 m long Teflon tube. The measurement of ammonia emissions was with three repetitions for each measurement, with a reference error of less than 5%. Emissions were measured at different time intervals: immediately after digestate distribution, 2 hours, 4 hours and the 24 hours after digestate application. The emission of ammonia from digestate without vegetation after 24 hours was 13 kg ha-1, for acidified digestate without vegetation 8.5 kg ha -1, while the acidified digestate with vegetation within 24 hours reached 2.5 kg of ha -1 ammonia emissions, five times lower than that of non-vegetation.

  • 288.
    Ejsmond, Anna
    et al.
    Univ Ctr Svalbard, Norway;Univ Bergen, Norway;Jagiellonian Univ, Poland.
    Korlowski, Jan
    Jagiellonian Univ, Poland.
    Ejsmond, Maciej J.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Jagiellonian Univ, Poland.
    Probing of mortality rate by staying alive: The growth-reproduction trade-off in a spatially heterogeneous environment2019In: Functional Ecology, ISSN 0269-8463, E-ISSN 1365-2435, Vol. 33, no 12, p. 2327-2337Article in journal (Refereed)
    Abstract [en]

    In many annual plants, mollusks, crustaceans and ectothermic vertebrates, growth accompanies reproduction. The growth curves of these organisms often exhibit a complex shape, with episodic cessations or accelerations of growth occurring long after maturation. The mixed allocation to growth and reproduction has poorly understood adaptive consequences, and the life-history theory does not explain if complex growth in short-lived organisms can be adaptive. We model the trade-off between growth and reproduction in a short-lived organism evolving in a metapopulation. Individuals occupy risky or safe sites throughout their lives, but are uncertain regarding the risk of death. Modelled organisms are allowed to grow and produce offspring at specified time points (moults), although we also consider scenarios that approximate continuous growth and reproduction. Certain combinations of risky to safe sites select for strategies with mixed allocation to growth and reproduction that bet-hedge offspring production in safe and risky sites. Our model shows that spatially heterogeneous environments select for mixed allocation only if safe sites do not become the prevailing source of recruits, for example, when risky sites are frequent. In certain conditions, growth curves are multi-phasic, with allocation to growth that stops, remains constant or accelerates during adult life. The resulting complex growth curves are more likely to evolve in short-lived organisms that moult several times per adult life. Our work shows that spatial heterogeneity can select for growth that accompanies reproduction and provides insights into the adaptive significance of complex growth curves. Short-lived crustaceans are particularly predisposed to exhibit complex growth patterns as an adaptive response to spatially heterogeneous environments. Our results suggest that standard statistical growth models assuming adult growth rate to only decelerate over life are not well suited to approximate growth curves of short-lived crustaceans. A free Plain Language Summary can be found within the Supporting Information of this article.

  • 289.
    Ejsmond, M. J.
    et al.
    Jagiellonian University, Poland.
    Blackburn, N.
    BIORAS, Denmark.
    Fridolfsson, Emil
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Haecky, P.
    BIORAS, Denmark.
    Andersson, A.
    Umeå University, Sweden;Umeå Marine Science Centre, Sweden.
    Casini, M.
    Swedish University of Agricultural Sciences, Sweden.
    Belgrano, A.
    Swedish University of Agricultural Sciences, Sweden;University of Gothenburg, Sweden.
    Hylander, Samuel
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Modeling vitamin B1 transfer to consumers in the aquatic food web2019In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, p. 1-11, article id 10045Article in journal (Refereed)
    Abstract [en]

    Vitamin B-1 is an essential exogenous micronutrient for animals. Mass death and reproductive failure in top aquatic consumers caused by vitamin B-1 deficiency is an emerging conservation issue in Northern hemisphere aquatic ecosystems. We present for the first time a model that identifies conditions responsible for the constrained flow of vitamin B-1 from unicellular organisms to planktivorous fishes. The flow of vitamin B-1 through the food web is constrained under anthropogenic pressures of increased nutrient input and, driven by climatic change, increased light attenuation by dissolved substances transported to marine coastal systems. Fishing pressure on piscivorous fish, through increased abundance of planktivorous fish that overexploit mesozooplankton, may further constrain vitamin B-1 flow from producers to consumers. We also found that key ecological contributors to the constrained flow of vitamin B-1 are a low mesozooplankton biomass, picoalgae prevailing among primary producers and low fluctuations of population numbers of planktonic organisms.

  • 290.
    Ejsmond, Maciej J.
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Jagiellonian University, Poland.
    Phillips, Karl P.
    University College Cork, Ireland;Marine Institute, Ireland.
    Babik, Wiesław
    Jagiellonian University, Poland.
    Radwan, Jacek
    Adam Mickiewicz University, Poland.
    The role of MHC supertypes in promoting trans-species polymorphism remains an open question2018In: Nature Communications, ISSN 2041-1723, E-ISSN 2041-1723, Vol. 9, no 1, p. 1-4, article id 4362Article in journal (Refereed)
  • 291.
    Ekstam, Börje
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Åtgärdsprogram för skaftslamkrypa Elatine hexandra [Lapierre] DC.2013Report (Refereed)
    Abstract [en]

    This action plan provides guidelines for preservation of the endangered plant Elatine hexandra (Six-stamened Waterwort) in Sweden. The action plan is a proposal, not a legally binding document.

    Elatine hexandra is a small, aquatic or amphibious, vascular herb in the family Elatinaceae. In Sweden, it usually appears as a summer annual on the very edge of freshwater lakes or streams. Some populations have over-wintering individuals that occur at depths well below the ice-cover. Typically, the habitat is a moderately wave exposed littoral with inorganic, silty-sandy substrate, covered with a thin layer of mud. The lake habitats have clear water, a near neutral pH and may rep-resent one of the two lake types that are included in the habitat directive, i.e. “Oligotrophic waters containing very few minerals of sandy plains” and “Oligotrophic to mesotrophic standing waters with vegetation of the Littorelletea uniflorae and/or of the Isoëto-Nanojuncetea”.

    The species has been found in approx. 55 Swedish lakes or running waters since 1980. With a few exceptions, the occurrences are restricted to river basins of southwest Sweden with outlets in Skagerrak and Kattegat (County Administration Boards of Värmland, Västra Götaland, Jönköping, Halland and Kronoberg). In the Swedish red list Elatine hexandra is classified as Endangered (EN).

    The main threats include deteriorating water quality. Eutrophication, acidification and brownification (increase in water color and dissolved organic matter) have adverse effects on growth and reproduction of the species. Other threats include exploitation of shorelines and water level regulations. The action plan proposes measures against deteriorating water quality in lakes with known occurrences of Elatine hexandra. Further, it points out the need for revision and ecological considerations of present water level regulations. Other suggestions aims to increase the conservation awareness among land owners, nature resource managers and municipality planners. These suggestions include production and spread of an information folder and implementation of conservation related information in the database WISS (Water Information System Sweden). WISS is an open information tool used in the planning cycle of river basin management. Finally, the action plan proposes additional investigations of the distribution in lakes and of the presence in seed-banks, as well as field studies on how growth and reproduction is affected by water regulations. With help of these results, lakes suitable for restoration measures can be selected. The action plan is valid for the period 2013-2018 and the costs are estimated to approx. 1 430 000 SEK

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    Åtgärdsprogram för skaftslamkrypa
  • 292.
    Ekvall, Mikael T.
    et al.
    Lund University.
    Hylander, Samuel
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Walles, Tim
    Lund University.
    Yang, Xi
    Lund University.
    Hansson, Lars-Anders
    Lund University.
    Diel vertical migration, size distribution and photoprotection in zooplankton as response to UV-A radiation2015In: Limnology and Oceanography, ISSN 0024-3590, E-ISSN 1939-5590, Vol. 60, no 6, p. 2048-2058Article in journal (Refereed)
    Abstract [en]

    The transparency regulator hypothesis (TRH) proposes that ultraviolet radiation (UVR) is a main driving force behind diel vertical migration (DVM) of zooplankton in clearwater systems. While previous studies have mainly studied DVM in relation to the TRH on a spatial scale across systems we here focus on long-term trends in a single system in order to assess if UVR explains observed patterns in DVM. We show that the strength of DVM in Daphnia is to a large extent explained by UVR and we demonstrate a tipping point at which the UVR intensity drastically affects the strength of DVM in Daphnia. In contrast, the strength of DVM could not be explained by the level of UVR among calanoid copepods. The amount of photoprotective compounds did not differ between zooplankton found at different depths indicating that zooplankton do not change their vertical position in relation to the amount of accumulated photoprotective compounds. In addition, we show that both Daphnia and calanoid copepods display patterns of size structured migration.

  • 293.
    Elin, Björnsson
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Avfall från hushåll i Småland: - kan det användas mer cirkulärt?2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    På vilket sätt vi slänger vårt avfall har betydelse för hur mycket som kan återvinnas. Enligt EU:s avfallshierarki måste hushållen som första steg minska sina avfallsmängder, därefter återanvända och materialåtervinna och sist energiåtervinna och deponera. Idag energiåtervinns 50% av hushållsavfallet i Sverige, vilket visar en möjlighet att flytta sig uppåt i avfallshierarkin.

     

    Syftet med detta examensarbete var att kartlägga uppkomna mängder hushållsavfall i Småland under år 2012 och 2013 samt att diskutera förbättringsmöjligheter för att få en större del av hushållsavfallet att bli utsorterat och därmed möjliggöra att mer avfall kan användas cirkulärt i samhället.

     

    År 2012 och 2013 genererades 393 000 respektive 407 000 ton hushållsavfall i Småland, och spridningen är stor i insamlade mängder per person och mellan kommuner. Fyra förbättringsmöjligheter för att öka utsorteringen av hushållsavfallet har identifierats. De är huvudsystemets betydelse, ekonomiskt styrmedel (viktbaserad avfallstaxa), samhällsplanering som styrmedel (matavfallssortering och materialströmmar) samt bättre statistiskt underlag. Studien visar att en ökad tillgänglighet till ÅVC/ÅVS kan bidra till bättre inlämning samt att om hushållen i Småland blir bättre på att sortera sitt kärl- och säckavfall kan avfallet till förbränning minskas med upp till 70%.

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  • 294.
    Elmberg, Johan
    et al.
    Kristianstad University.
    Berg, Charlotte
    Swedish University of Agricultural Sciences.
    Lerner, Henrik
    Ersta Sköndal Bräcke University College.
    Waldenström, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Hessel, Rebecca
    Kristianstad University.
    Potential disease transmission from wild geese and swans to livestock, poultry and humans: a review of the scientific literature from a One Health perspective2017In: Infection Ecology & Epidemiology, ISSN 2000-8686, E-ISSN 2000-8686, Vol. 7, no 1, p. 1-21, article id 1300450Article in journal (Refereed)
    Abstract [en]

    There are more herbivorous waterfowl (swans and geese) close to humans, livestock and poultry than ever before. This creates widespread conflict with agriculture and other human interests, but also debate about the role of swans and geese as potential vectors of disease of relevance for human and animal health. Using a One Health perspective, we provide the first comprehensive review of the scientific literature about the most relevant viral, bacterial, and unicellular pathogens occurring in wild geese and swans. Research thus far suggests that these birds may play a role in transmission of avian influenza virus, Salmonella, Campylobacter, and antibiotic resistance. On the other hand, at present there is no evidence that geese and swans play a role in transmission of Newcastle disease, duck plague, West Nile virus, Vibrio, Yersinia, Clostridium, Chlamydophila, and Borrelia. Finally, based on present knowledge it is not possible to say if geese and swans play a role in transmission of Escherichia coli, Pasteurella, Helicobacter, Brachyspira, Cryptosporidium, Giardia, and Microsporidia. This is largely due to changes in classification and taxonomy, rapid development of identification methods and lack of knowledge about host specificity. Previous research tends to overrate the role of geese and swans as disease vectors; we do not find any evidence that they are significant transmitters to humans or livestock of any of the pathogens considered in this review. Nevertheless, it is wise to keep poultry and livestock separated from small volume waters used by many wild waterfowl, but there is no need to discourage livestock grazing in nature reserves or pastures where geese and swans are present. Under some circumstances it is warranted to discourage swans and geese from using wastewater ponds, drinking water reservoirs, and public beaches. Intensified screening of swans and geese for AIV, West Nile virus and anatid herpesvirus is warranted.

  • 295.
    Elmlund, Louise
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Söderberg, Pernilla
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Suriyanarayanan, Subramanian
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences.
    Nicholls, Ian A.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Chemistry and Biomedical Sciences. Uppsala University.
    A Phage Display Screening Derived Peptide with Affinity for the Adeninyl Moiety2014In: Biosensors, ISSN 2079-6374, Vol. 4, no 2, p. 137-149Article in journal (Refereed)
    Abstract [en]

    Phage display screening of a surface-immobilized adenine derivative led to the identification of a heptameric peptide with selectivity for adenine as demonstrated through quartz crystal microbalance (QCM) studies. The peptide demonstrated a concentration dependent affinity for an adeninyl moiety decorated surface (KD of 968 ± 53.3 μM), which highlights the power of piezoelectric sensing in the study of weak interactions. 

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    Biosensors
  • 296.
    Elmqvist, Joakim
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Vad händer med syret? En kvalitativ studie av elevers föreställningar gällande hur respirationssystemet och cirkulationssystemet samverkar2018Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Tidigare studier av hur organsystem samverkar visar på en bristande förståelse hos elever. Syftet med denna studie var att skapa bättre förutsättningar för den undervisning som ska utveckla elevers förståelse av kroppen som en funktionell enhet. Studiens empiri har samlats in med hjälp av semistrukturerade intervjuer där 16 stycken elever har medverkat. Med hjälp av en tematisk analys har särskilda mönster upptäckts och resulterat olika teman, som har synliggjort elevers föreställningar av hur organsystemen samverkar. Studiens resultat och diskussionsavsnitt kan förbättra en undervisning som tar utgångspunkt i hur kroppens organsystem samarbetar.

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    fulltext
  • 297.
    Engkvist, Fanny
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Hur hanteras och uppfattas övergödning i Östersjön?: En fallstudie av nationella handlingsplaner för genomförandet av Baltic Sea Action Plan och uppfattningar kring övergödning i Östersjöregionen2014Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In November 2007 the countries around the Baltic Sea signed the Baltic Sea Action Plan (BSAP). The action plan was an initiative from HELCOM due to the environmental status in the Baltic Sea. The action plan implemented a new approach with measures targeting the whole ecosystem. Eutrophication, hazardous substances, biodiversity and maritime activities constituted the main segments. The parties were to establish national implementation plans to fulfil the BSAP goals, which shall lead to good environmental status in the Baltic Sea by 2021.  

    The aim of this thesis is to investigate the points in common regarding conceptions of eutrophication in the Baltic Sea between the management, the science, the media and the public. There are often complex connections between scientific knowledge and decision-making. With the purpose to elucidate these connections the risk management of eutrophication was compared with the scientific knowledge in the area along with the perceptions of the public and media.

    The implementation plans of the HELCOM parties differ in both content and ambitions. Overall the implementation plans are technical and many of them give no background descriptions to the causes of eutrophication. The scientific uncertainty that surrounds the calculation models of eutrophication is mentioned in about half of the implementations plans. Some uncertainty is mentioned due to the timescale of the effects of the measures. This can be compared with the fact that some scientists mean that the BSAP goals are unrealistic. Several parties mention the agriculture as an important sector for the reduction of the nutrient supply to the Baltic Sea. The Russian, Lithuanian and Estonian implementation plans also put forward the municipality treatment plants as important actors. There is a big difference between how many times the notion “eutrophication” is mentioned in the implementation plans. In the German implementation plan the notion is mentioned most frequently (29 times), while the Danish implementation plan only mention the notion twice. In the Finnish, Polish and German implementation plans eutrophication is described as a big threat. Only in the Latvian, Polish and German implementation plans eutrophication is described as a risk. The analysis of the implementation plan content shows that the parties has not succeeded to fully use the risk notion in relation to eutrophication. This can affect the risk governance, but also the perception of eutrophication among different stakeholders. Both media and politics affect the complex interactions that constitute the fundament of the relationship between scientific knowledge and public risk awareness. The consequence of eutrophication that is given most of the space in the Swedish newspaper Dagens Nyheter is algal growth. 73 % of the Swedes consider the algal growth as a rather big issue or a very big issue. A plausible conclusion is that there is a connection between the descriptions of eutrophication in Swedish media and the perceptions and knowledge of eutrophication by the Swedish respondents.

    The perceptions and management of eutrophication in the Baltic Sea are surrounded by complex interactions, uncertainty in the scientific basis and ambiguous opinions. Despite this eutrophication is often treated as a simple risk. For the purpose of successful implementation of the action plans is it important that the public participate in the elaboration of the risk measures. To accomplish real change it might be necessary to make the complex interactions more visible and to make the public participate more.   

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    fulltext
  • 298.
    Engkvist, Roland
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Nilsson, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Malmfjärden - vatten och biologi 20112013Report (Other academic)
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    LNU 2013 6 Malmfjarden_vatten_biologi.pdf
  • 299.
    Engstedt, Olof
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Engkvist, Roland
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Larsson, Per
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Elemental fingerprinting in otoliths reveals natal homing of anadromous Baltic Sea pike (Esox lucius L.)2014In: Ecology of Freshwater Fish, ISSN 0906-6691, E-ISSN 1600-0633, Vol. 23, no 3, p. 313-321Article in journal (Refereed)
    Abstract [en]

    We examined the element pattern in the otoliths of a migratory fish species that inhabit the coastal areas in the brackish of the Baltic Sea. The northern pike (Esox lucius) show migratory behaviour, spawning in streams and rivers and foraging in the sea. We examined spawning migration in four nearby streams in the south-west part of the Baltic. Otolith analysis by microPIXE revealed unique elemental patterns (Sr, Zn, Br, Co and Mn) for the juveniles in each of the different streams. The strontium signal in the otolith of the juveniles was used as an indicator of freshwater origin and the time spent in the stream. Adult pike in their migrating spawning phase were caught in each of the streams. The elemental composition in otoliths in their freshwater phase (using juvenile pike in the streams as references) was determined. A principal component analysis showed that the elemental fingerprint during the freshwater phase several years back in time was similar for the adult fish and for juveniles inhabiting the stream today. The results indicated natal homing of the adults to a specific stream, a conclusion that was strengthened by the fact that marked fish returned to spawn over consecutive years. Anadromous pike in the Baltic Sea may thus be divided in subpopulations. The results of the study may have implications for fishery management, as pike in the Baltic Sea cannot be seen as homogenous population.

  • 300.
    Engstedt, Olof
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Nilsson, Jonas
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Larsson, Per
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Habitat restoration: A sustainable key to management2018In: Biology and Ecology of Pike / [ed] Christian Skov and Anders Nilsson, Boca Ratón: CRC Press, 2018, 1, p. 248-268Chapter in book (Refereed)
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