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  • 101.
    Land, Magnus
    et al.
    Luleå University of Technology.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Öhlander, Björn
    Past and present weathering rates in northern Sweden1999Ingår i: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 14, nr 6, s. 761-774Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Past and present chemical weathering rates in granitic till have been estimated. The Kalix River watershed in northern Sweden was used as a study area in which 17 evenly distributed soil profiles were investigated. The two estimations are based on elemental depletion trends in soil profiles and input/output budgets for the elements in the watershed, respectively. In the calculations of the past weathering rate it was assumed that zircon is resistant, and thus Zr was considered to be immobile during weathering. The long-term average chemical erosion rate since the area was deglaciated 8700 a ago, expressed as the sum of major element oxides (SiO2, Al2O3, CaO, Fe2O3, K2O, MgO, MnO, Na2O), was estimated to be 5.8 g·m−2·a−1. In terms of base cation (Ca2+, Mg2+, Na+, K+) depletion this corresponds to 0.36 keq·ha−2·a−1. All elements analysed have been depleted from the E-horizon, and the most affected elements are P with an average mass loss of 86% (as P2O5), La 81%, Co 78%, Cu 77% and Ni 76%. The present-day weathering rate was calculated as the difference between outputs and inputs in the Kalix River watershed. The input was considered as the contribution from precipitation, while the output was calculated as the sum of (1) the river-transported dissolved fraction, (2) the river-transported suspended non-detrital fraction (chemically precipitated Fe- and Mn-oxy-hydroxides and matter sorbed on these particles), and (3) the biotic nutrient net uptake. River-transported outputs were measured for an annual cycle starting in September 1991 and ending in August 1992. The present-day chemical erosion rate of the till was estimated to be 6.3 g·m−2·a−1 (sum of major element oxides), or a base cation flux of 1.42 keq·ha−2·a−1. Part of this present-day rate is related to carbonate weathering in the Caledonian mountain range which makes it difficult to compare the present weathering rate with the historical weathering rate. After correction for carbonate weathering the resulting present-day weathering rate of granitic till in terms of base cation flux was estimated to be 0.65–0.75 keq·ha−2·a−1. This result indicates that the present cation flux has increased by a factor of 1.8–2.1 compared to the long-term average. However, given the uncertainties introduced by the carbonates in the Caledonian mountain range it is not possible to prove any significant difference between the mean post-glacial and the present-day weathering rate with the methods used in this study.

  • 102.
    Land, Magnus
    et al.
    Luleå University of Technology.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Thunberg, Jonas
    Luleå University of Technology.
    Solid speciation and fractionation of rare earth elements in a Spodosol profile from northern Sweden as revealed by sequential extraction1999Ingår i: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 160, nr 1-2, s. 121-138Artikel i tidskrift (Refereegranskat)
  • 103.
    Larsson, Jenny
    et al.
    Stockholms Universitet.
    Gustafsson, Örjan
    Stockholms Universitet.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Evaluation and optimization of two complementary cross-flow ultrafiltration systems toward isolation of coastal surface water colloids2002Ingår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 36, nr 10, s. 2236-2241Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    While colloidal phases in natural waters are important to the speciation and bioavailability of trace metals and organic compounds, accurate isolation of these submicron entities from their lower molecular-weight counterparts has proved challenging. Here, both laboratory and field experiments have been conducted to constrain integrity aspects of two different cross-flow filtration (CFF) systems. We tested both a commonly applied 5000 cm2 CFF system (Pellicon2, Millipore; manufacturer-specified 1 and 3 kDa cutoff) and a less studied mini-CFF system with a 50 cm2 membrane area (Pellicon Lab Scale XL, Millipore; with 5, 10, 100, and 1000 kDa cutoff). A natural water matrix amended with a series of fluorescently tagged colloidal probes was employed to demonstrate that a cross-flow ratio (CFR; retentate-to-permeate flux) > 15 was required for both of these systems to obtain high recoveries of colloids. Contrary to previous calibrations of CFF, also at colloid concentrations characteristic of natural waters, the established retention profiles for the colloid probes on these systems, when operated under CFR > 15, affirmed the manufacturer-specified cutoff values (in parentheses): 2.4 kDa (1 kDa), 3.3 kDa (3 kDa), 6.1 kDa (5 kDa) and 8.7 kD (10 kDa). A concentration factor (cf) > 10 was found necessary for the reliable determination of the colloidal pool of several elements in the surface waters of the open Baltic Sea. Application of CFR > 15 and cf > 10 returned recoveries around 100% for the studied organic carbon, Ca, Mo, Fe, Cu, and Ni on both systems. Furthermore, the trend of colloid association for the transition elements in the offshore Baltic surface waters followed expectations from their Irving-Williams series of coordination chemistry.

  • 104.
    Lundberg, Angela
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Eriksson, Barbro
    Luleå tekniska universitet.
    Erixon, Peter
    Fell, Astrid
    Ingri, Johan
    Lundmark, Carina
    Luleå tekniska universitet, Institutionen för ekonomi, teknik och samhälle, Samhällsvetenskap.
    Maurice, Christian
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rönnbäck, Brit
    Teaching community in sustainable development: aim, realization and evaluation. Final report from project "Teaching communities" (självförbättrande lärartem)2006Rapport (Övrigt vetenskapligt)
    Abstract [en]

    A model for the educational development of university teachers (a type of teaching community) has been tested. University staff from different faculties worked and reflected together over the teaching and learning practice in a couple of courses. The community was supervised by an educational developer with a doctoral degree in psychology, and they worked in close collaboration with both undergraduate students and PhD students. The teaching staff that participated improved their teaching skills, extended their repertoire of learning tools, and experienced increased self-reliance. Their motivation and enthusiasm for teaching increased, and today they act as "missionaries" for good teaching and learning practices at the University. It was not obvious, however, that this educational development promoted their academic careers. New project ideas emerged from the teaching community.

  • 105. Malinovskiy, Dmitry
    et al.
    Dahlqvist, Ralf
    Swedish Museum of Natural History.
    Baxter, Douglas
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rodushkin, Ilya
    Performance of diffusive gradients in thin films for measurements of the isotopic composition of soluble Zn2005Ingår i: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 537, nr 1-2, s. 401-405Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The application of diffusive gradients in thin films (DGT) samplers for measurements of the isotopic composition of soluble Zn by multi-collector inductively coupled plasma mass spectrometry (MC-ICPMS) was tested under laboratory conditions. The effect of diffusion in hydrogels as a possible source of fractionation was investigated by measuring Zn isotope ratios for different fractions of Zn accumulated by DGT and comparing with the bulk isotope composition of the solution. An important finding of this study is that, provided quantitative elution is obtained, no fractionation of Zn isotopes due to the diffusion process is detectable within the reported precision of MC-ICPMS measurements. Consequently, DGT samplers are suitable for studies of the Zn isotopic composition in natural waters.

  • 106. Malinovskiy, Dmitry
    et al.
    Rodushkin, Ilia
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Baxter, Douglas
    Öhlander, Björn
    Ingri, Johan
    Fe isotope fractionation during redox cycling of Fe in lake water2004Ingår i: Vol. 68, nr 11, Special suppl.Artikel i tidskrift (Refereegranskat)
  • 107. Malinovskiy, Dmitry
    et al.
    Rodushkin, Ilya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Baxter, Douglas
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Öhlander, Björn
    Molybdenum isotope ratio measurements on geological samples by MC-ICPMS2005Ingår i: International Journal of Mass Spectrometry, ISSN 1387-3806, E-ISSN 1873-2798, Vol. 245, nr 1-3, s. 94-107Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    A method using multiple-collector inductively coupled plasma mass spectrometry (MC-ICPMS) for the precise measurement of Mo isotopic composition in geological samples has been developed. Purification of Mo for isotope ratio measurements was realized by ion-exchange chromatography using the chelating resin Chelex-100. This technique allows an efficient separation of Mo from an excess of Fe in samples and at the same time provides quantitative recovery of Mo. Instrumental mass discrimination is corrected by using Pd spiking and normalization to the 105Pd/104Pd ratio. Mo isotope ratios of samples are expressed in per mil relative to those of the bracketing in-house Mo standard. The long-term reproducibility at the two standard deviation level is 0.04, 0.06, 0.08 and 0.14‰ for 96Mo/95Mo, 97Mo/95Mo, 98Mo/95Mo and 100Mo/95Mo ratio measurements, respectively. The technique has been applied to measurement of the Mo isotopic composition of freshwater sediments and molybdenites. Mass-dependent variations in the isotopic composition of Mo spanning the range of 2.2‰ in terms of the 97Mo/95Mo ratio for two sediment columns from different redox environments have been resolved. These results show that Mo isotope effects induced by geochemical processes operating during weathering and transport of Mo to the oceans should be quantified in order to interpret global Mo isotope budget and make use of stable Mo isotopes as proxy for redox conditions in the geological past.

  • 108. Malinovskiy, Dmitry
    et al.
    Rodushkin, Ilya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Shcherbakova, Elena
    Ponter, Christer
    Analytica AB.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Fractionation of Fe isotopes as a result of redox process in a basin2005Ingår i: Geohimiâ, ISSN 0016-7525, Vol. 43, nr 8, s. 878-885Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper presents the results of a study of Fe isotope fractionation due to seasonal redox variations in water and bottom sediments (BS) of fresh-water basins. Fe isotopic ratios were measured using multicollector inductively coupled plasma mass spectrometry (MC-ICP-MS). The investigation of suspended matter (SM) at the oxic-anoxic interface showed a significant positive shift in δ56Fe values between anoxic waters with dissolved Fe(II) and SM after Fe(II) oxidation and precipitation of Fe(III) oxides. Data on Fe content and isotope composition suggest that Fe(II) oxidation is accompanied by equilibrium Fe isotope fractionation. Potentials and limitations of the use of Fe isotope data for the reconstruction of pre-existing geochemical conditions in basins are outlined

  • 109. Malinovskiy, Dmitry
    et al.
    Stenberg, Anna
    Luleå tekniska universitet.
    Rodushkin, Ilia
    Andren, Henrik
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Öhlander, Björn
    Baxter, Douglas
    Performance of high resolution MC-ICP-MS for Fe isotope ratio measurements in sedimentary geological materials2003Ingår i: Journal of Analytical Atomic Spectrometry, ISSN 0267-9477, E-ISSN 1364-5544, Vol. 18, nr 7, s. 687-695Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    High resolution MC-ICP-MS is used for the precise measurement of variations in the isotopic composition of Fe in ferromanganese concretions and sediments relative to IRMM-014 standard. The sensitivity for 56Fe in high resolution mode was 3 V per mg lm1 Fe, a figure that is comparable to those from other MC-ICP-MS instruments operated at low resolution. Incorporation of a guard electrode and the efficient ion transmission capabilities of the Neptune MC-ICP-MS instrument are responsible for the high sensitivity. It was observed that the use of HCl resulted in the formation of ClOH+, causing interference with 54Fe in particular. This acid has been preferred in some cases over HNO3 to minimize formation of ArN+, the major interferent for 54Fe. Using the high resolution mode of the Neptune, the nature of spectral interferences is unimportant as all are completely resolved and will not affect the accuracy of the determined Fe isotope ratios. As the instrument also provides flat-topped peaks, high resolution operation does not necessarily result in impaired precision, providing that higher concentrations are used to compensate for the loss in sensitivity compared with the low resolution mode. In the present work, external reproducibilities of 56Fe/54Fe and 57Fe/54Fe isotope ratios were better than 50 ppm (one standard deviation) at a concentration of 5 mg lm1. The level of instrumental mass discrimination observed for raw ratios drifted by as much as 0.09% per mass unit over a measurement session, but could be corrected on-line by simultaneous monitoring of the 62Ni/60Ni isotope ratio. Variations in the Fe concentrations or the acid strength of measurement solutions were found to affect the apparent mass discrimination. Increasing the Fe concentration caused a relative decrease in the raw 56Fe/54Fe and 57Fe/54Fe isotope ratios, thus ruling out the space charge effect as the explanation for this phenomenon. Instead, it is suggested that the larger dry aerosol particles formed at higher Fe concentrations are not completely vaporized until later in the plasma, thus reducing the relative rate of diffusional losses of lighter 54Fe from the central channel. However, application of on-line correction using Ni could adequately account for this effect. From the results for a variety of sedimentary geological materials, analysis of three-isotope data revealed that equilibrium fractionation of Fe occurred during deposition. To be able to distinguish between equilibrium and kinetic fractionation processes, it is imperative to collect accurate and precise data for the 56Fe/54Fe and 57Fe/54Fe isotope ratios. These requirements are readily fulfilled by applying high resolution MC-ICP-MS and on-line correction for instrumental mass discrimination using Ni.

  • 110.
    Murphy, Melissa J.
    et al.
    Department of Earth Science, University of Oxford.
    Strandmann, P.A.E. Pogge von
    Institute of Earth and Planetary Science, University College London.
    Porcelli, Don
    Department of Earth Science, University of Oxford.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Li Isotope Behaviour in the Low Salinity Zone During Estuarine Mixing2014Ingår i: Procedia: Earth and Planetary Science, ISSN 1878-5220, Vol. 10, s. 204-207Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    During mixing of river water and seawater, changes in water chemistry can affect the behaviour of elements in estuaries, and consequently may alter their input into the oceans. In order to evaluate this, lithium (Li) concentrations and isotope compositions of estuarine waters from the Kalix and Råne River estuaries (Northern Sweden) have been determined. The waters span δ7Li values of +21.7 to +30.4 ‰, with the lowest values found within the shallowest samples with the lowest salinities. Dissolved Li concentrations show near conservative behaviour with increasing salinity; however their δ7Li isotopic compositions may be explained by either conservative mixing with an intermediate salinity Bothnian Bay end member; or non-conservative behaviour, with excess Li added to solution during mixing. The non-conservative behaviour of Li might be ascribed to cation exchange processes with suspended riverine particles or weathering during mixing with seawater within the low salinity zones of the Kalix and Råne River estuaries.The existence of non-conservative mixing of Li in estuarine environments suggests that the Li isotopic riverine input signature could be modified within estuaries, which may affect the marine and palaeo-marine budgets. Hence, this has important implications for the estimation of the fluvial Li flux into the oceans

  • 111.
    Nkandu, C.
    et al.
    University of Zambia.
    Sinkala, Thomson
    Simukanga, S.
    University of Zambia.
    Pettersson, Ulf
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Seasonal variations in the turbidity and composition of suspended solids in the Kafue and Mwambashi rivers and the effect of mining effluent1996Ingår i: Zambia Journal of Applied Earth Sciences, ISSN 1010-5913, Vol. 10, nr 1, s. 33-42Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The paper discusses the seasonal changes in the turbidities of the Kafue and Mwambashi Rivers. These turbidities are compared to the maximum volume of water which could be passed through a filter at those turbidities. A mathematical analysis shows that the variation of the maximum water volume filtered with turbidity should be approximately hyperbolic. This is what is noticed at Garneton, Fisher's farm and Gwabi. At Machiya Ferry however, a different variation was encountered. It is also noticed that unlike at the other three sampling points, at Machiya, the highest turbidities occur during the dry season. It is thought this could be due to the ongoing sedimentation of coarser size fractions as well as the precipitation of new finer solids which is taking place in the river. The effect of mining effluent on the turbidity of the Mwambashi River is also discussed.

  • 112.
    Nordblad, Fredrik
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ecke, Frauke
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Geochemistry in a boreal stream after a major forest fire: implications for a changing climate2011Konferensbidrag (Övrigt vetenskapligt)
  • 113.
    Nordblad, Fredrik
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rodushkin, Ilya
    Engström, Emma
    Ecke, Frauke
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Öhlander, Björn
    Ingri, Johan
    Stream water geochemistry of boron and boron isotopes in a small boreal catchment affected by a major forest fire2009Ingår i: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 73, nr 13, Supp. S, s. A952-Artikel i tidskrift (Övrigt vetenskapligt)
    Abstract [en]

    Previous research [1] has suggested that the boron (B) isotope system has a potential to be used as a tracer for detecting historic wood fire events. It was hypothesized that highly elevated B concentrations in sediments of a lake, accompanied by an enrichment of 10B, were a result of an urban wood fire event in the 19th century. The δ11B decrease in these sediments exceeded 9 ., coinciding with a peak in the B concentration.To evaluate this hypothesis, seasonal isotopic pattern of boron (B) was investigated during spring and summer 2007 in a small stream draining a boreal forest area which was severely burnt in a major forest fire in the summer of 2006. Dissolved (< 0.22 µm) boron concentrations of the burnt area were significantly higher compared to a non-burnt reference stream, while 11B/10B ratios were significantly lower. Dissolved δ11B differences between the reference and the burnt area stream were found to be -9 to -22 .. We interpret the elevated B concentrations, accompanied by enrichment of 10B, in the burnt stream as wood and plant ash leaching of biogenic B from the burnt forest by surface run-off. Our results suggest that a boreal forest fire event significantly increases the leached amount of isotopically lighter B in the dissolved phase of stream run-off.[1] Peltola & Åström (2006), Appl. Geochem. 21 (2006) 941-948.

  • 114.
    Pallavicini, Nicola
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik. ALS Laboratory Group, ALS Scandinavia AB, Luleå, Sweden.
    Engström, Emma
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik. ALS Laboratory Group, ALS Scandinavia AB, Luleå, Sweden.
    Baxter, Douglas C.
    ALS Laboratory Group, ALS Scandinavia AB, Luleå, Sweden.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Hawley, Scott
    Department of Earth Sciences, Durham University, Durham, UK.
    Hirst, Catherine
    Department of Geosciences, Natural History Museum, Stockholm, Sweden.
    Rodushkina, Katerina
    Department of Chemistry, Uppsala University, Uppsala, Sweden.
    Rodushkin, Ilya
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik. ALS Laboratory Group, ALS Scandinavia AB, Luleå, Sweden.
    Ranges of B, Cd, Cr, Cu, Fe, Pb, Sr, Tl, and Zn Concentrations and Isotope Ratios in Environmental Matrices from an Urban Area2018Ingår i: Journal of Spectroscopy, ISSN 2314-4920, E-ISSN 2314-4939, s. 1-17, artikel-id 7408767Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Isotopic information may provide powerful insight into the elemental cycling processes which occur in natural compartments. Further implementation of isotopic techniques in natural sciences requires a better understanding of the range of elemental and isotopic compositional variability in environmental matrices. This study assesses the local-scale concentration and isotopic composition variability of nine elements: boron (B), cadmium (Cd), chromium (Cr), copper (Cu), iron (Fe), lead (Pb), strontium (Sr), thallium (Tl), and zinc (Zn) in lysimetric waters, mushrooms, litter, needles, leaves, and lichens. Sequential extractions were also performed on soil samples from 6 depth profiles providing more detailed information on the variability of elemental concentrations and isotope ratios between the elemental pools present in soil. For most of the sample types studied the range of isotopic variability between samples spans almost the entire ranges reported in the literature for natural samples. These results represent a starting point for discussing the role of natural variability in isotopic studies (for example, as a limiting factor in the use of isotopic mixing models) and a baseline for future in-depth studies examining the controls on isotope fraction in natural systems

  • 115.
    Pallavicini, Nicola
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Engström, Emma
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Baxter, Douglas C.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Rodushkin, Ilya
    Cadmium isotope ratio measurements in environmental matrices by MC-ICP-MS2014Ingår i: Journal of Analytical Atomic Spectrometry, ISSN 0267-9477, E-ISSN 1364-5544, Vol. 29, nr 9, s. 1570-1584Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Various stages of an analytical method for high-precision cadmium (Cd) isotope ratio measurements by MC-ICP-MS (sample preparation, matrix separation, instrumental analysis and data evaluation) were critically evaluated and optimized for the processing of carbon-rich environmental samples. Overall reproducibility of the method was assessed by replicate preparation and Cd isotope ratio measurements in various environmental matrices (soil, sediment, Fe-Mn nodules, sludge, kidney, liver, leaves) and was found to be better than 0.1‰ (2σ for δ114Cd/110Cd) for the majority of samples. Cd isotope ratio data for several commercially-available reference materials are presented and compared with previously published results where available. The method was used in a pilot study focusing on the assessment of factors affecting Cd isotope composition in tree leaves. A summary of results obtained for a large number (n > 80) of birch (Betula pubescenes) leaves collected from different locations in Sweden and through the entire growing season is presented and potential reasons for observed variability in Cd isotope composition are discussed. Seasonal dynamics of element concentrations and isotope compositions in leaves were also compared for Os, Pb, Zn and Cd.

  • 116.
    Peinerud, Elsa
    et al.
    Luleå tekniska universitet.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Pontér, Christer
    Luleå tekniska universitet.
    Non-detrital Si concentrations as an estimate of diatom concentrations in lake sediments and suspended material2001Ingår i: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 177, nr 3-4, s. 229-239Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    This paper evaluates a method, based on normalization with Al, to estimate the concentration of diatoms in suspended and deposited sediments. Provided that Al exists primarily in the detrital phase, one can calculate the fraction of non-detrital Si (i.e. biogenic Si). Suspended matter and sediment in two lakes in northern Sweden have been analyzed. Results from the normalization method are compared with microscope count data. The results from the two methods differ somewhat. Partly dissolved diatom frustules may explain part of this discrepancy. These remnants can hardly be recognized as diatoms. Therefore, they are not counted during the microscopic analysis, although they contribute to the concentration of biogenic Si. Another factor is the differences in Si content among different types of diatoms. We show that the calculated concentrations of non-detrital Si are good estimates of the diatom concentrations. By using normalization as a tool, reasonable estimates of the stocks of biogenic Si can be obtained rapidly. Using these estimates as a guide, sites where considerable changes in diatom productivity and/or dissolution rates have occurred can be identified.

  • 117.
    Pekka, Larisa
    et al.
    Luleå tekniska universitet.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Widerlund, Anders
    Mokrotovarova, Olga
    Murmansk Areal Department for Hydrometeorology and Environmental Monitoring.
    Riabtseva, Margarita
    Federal State Institution Murmansk Territorial Fund for geological Information, Apatity.
    Öhlander, Björn
    Geochemistry of the Kola River, northwestern Russia2004Ingår i: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 19, nr 12, s. 1975-1995Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Kola River in the northern part of the Kola Peninsula, northwestern Russia, flows into the Barents Sea via the Kola Bay. The river is a unique place for reproduction of salmon and an important source of drinking water for more than 500,000 people in Murmansk and the surrounding municipalities. To evaluate the environmental status of the Kola River water, sampling of the dissolved (<0.22 μm) and suspended (>0.22 μm) phases was performed at 12 sites along the Kola River and its tributaries during 2001 and 2002. Major (Ca, K, Mg, Na, S, Si, HCO3 and Cl) and trace (Al, As, Ba, Cd, Co, Cr, Cu, Fe, Mn, Mo, Ni, Pb, Sr, Ti, and Zn) elements, total and particulate organic C (TOC and POC), N and P were analysed. Comparison with the boreal pristine Kalix River, Northern Sweden, shows that, except for Na, Cl, Al, Cu and Ni, which exceed the concentrations in the Kalix River by as much as 2–3 times, the levels of other major and trace elements are close to or even below the levels in the Kalix River. However, the results also demonstrate that pollutants from the three major sources: (1) the Cu–Ni smelter in Monchegorsk, (2) the open-pit Fe mine and ore concentration plant in Olenegorsk, and (3) the Varlamov, the Medveziy and the Zemlanoy creeks, draining the area of the large agricultural enterprises in the lower part of the watershed, have a major influence on the water quality of the Kola River.

  • 118.
    Pekka, Larissa
    et al.
    Luleå tekniska universitet.
    Halmeenpää, Hanna
    North Ostrobothnia Regional Centre, Oulu.
    Ecke, Frauke
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Vuori, Kari-Matti
    Finnish Environment Institute, Oulu.
    Mokrotovarova, Olga
    Murmansk Areal Department for Hydrometeorology and Environmental Monitoring.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Assessing pollution in the Kola River, northwestern Russia, using metal concentrations in water and bryophytes2008Ingår i: Boreal environment research, ISSN 1239-6095, E-ISSN 1797-2469, Vol. 13, nr 1, s. 15-30Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Intensive Cu-Ni and Fe mining and smelting in northwestern Russia constitutes a potential risk of pollution in the Kola River. We assessed the degree of pollution along the Kola River by means of overall water quality evaluation and analyses of metals in water samples (dissolved and particulate fractions) and aquatic mosses. The observed pollutant levels were compared with those in unpolluted reference rivers. The results indicate relatively low overall contamination in the Kola River, although Cu and Ni levels are elevated relative to the reference data. Furthermore, PCA ordination models identified clear metal concentration patterns along the river. Al, Cd, Co, Fe, Pb and Zn exhibited an almost continuous increase from the headwaters to the river mouth, whereas As, Ba, Cu, Mn, Mo and Ni showed their highest concentrations in the headwaters, close to the mining areas, relatively low concentrations in the middle parts of the river and elevated concentrations at the river mouth. Bryophyte analysis appeared to be a more sensitive tool for metal pollution assessment than metal concentrations in water.

  • 119. Pettersson, Ulf
    et al.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    The effect of mining activities on water quality in the Kafve River Copperbelt, Zambia: a pilot study1993Rapport (Övrigt vetenskapligt)
  • 120.
    Pettersson, Ulf T.
    et al.
    Zambezi River Authority, PO Box 30233, Lusaka.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    The geochemistry of Co and Cu in the Kafue River as it drains the Copperbelt mining area, Zambia2001Ingår i: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 177, nr 3-4, s. 399-414Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Samples of the dissolved ( < 0.45 μ m) and suspended (> 0.45 μ m) phases have been collected in the Kafue River during a 1-year cycle. Within the mining area, the concentrations of Co, Cu and S in the river occasionally increase more than 100 times compared to concentrations upstream from the mining area. The highest concentrations of dissolved Cu (3.4 μ M) and Fe (4.2 μ M) are found during high water discharge, probably indicating a washout of leached weathering products from spoil heaps. High levels of Co appear to originate from one point source, the location where the Co ore is treated. In the Kafue River, secondary Mn- and Fe-rich particles are formed, on which Co and Cu, respectively, are enriched. The elements associated to secondary Fe and Mn particles are enriched at the sediment surface in the river due to redox processes. Hence, secondary particles and sorbed trace elements may be resuspended and transported further downstream in the river system. However, very high concentrations of Cu (1%) and Co (0.1%) in the sediment are caused by primary sulphides.

  • 121.
    Pettersson, Ulf T.
    et al.
    Luleå tekniska universitet.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andersson, Per S
    Hydrogeochemical processes in the Kafue River upstream from the Copperbelt mining area2000Ingår i: Aquatic geochemistry, ISSN 1380-6165, E-ISSN 1573-1421, Vol. 6, nr 4, s. 385-411Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Frequent sampling during an annual cycle of dissolved(<0.45 μm) and suspended (>0.45 μm) elementshas been conducted in the Kafue River at Raglan'sFarm, upstream from the mining activities within theCopperbelt Province, Zambia. Additional sampling ofsediment and interstitial pore water was conductedduring low water discharge. The presence of carbonateswithin the drainage basin naturally gives rise to highelement concentrations in the dissolved phase(Ca = 626, Mg = 494, Na = 360 and K = 24 mmol l-1).During the rainy season the relative composition ofthe dissolved elements indicated a wash out ofaccumulated weathering products and mineralisedorganic material from the unsaturated zone of the soilprofile. High concentrations of dissolved Al, Fe andMn were measured during high water discharge. At lowwater discharge the sediment was a major source of Fe,Mn and associated Co and Cu to the water column.Enhanced concentrations of dissolved and suspended S,Co and Cu during the rainy season indicated thatatmospheric deposited particles from the mining areawere washed out into the river. Autochthonousformation of particles rich in Si indicated diatomproduction during low water discharge.

  • 122.
    Pontér, Christer
    et al.
    Luleå tekniska universitet.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Boström, Kurt
    Geochemistry of manganese in the Kalix River, northern Sweden1992Ingår i: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 56, nr 4, s. 1485-1494Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Dissolved and suspended Mn in the Kalix River, northern Sweden, were measured weekly over a period of eighteen months. During the same period four lakes in the Kalix catchment were sampled at their outlets and in vertical profiles within the lakes, together with a stream draining a series of mires with shallow lakes. Snow melting in mid-May increased the dissolved Mn concentration in the river tenfold, compared with a concentration of 5 μg L-1 during the winter discharge (January to April). We suggest that the increase was caused by Mn-rich mire water mixing with melting snow and being transported to the river. Large concentrations of dissolved Mn built up in the hypolimnion of the lakes studied during the icecovered period. Break-up of the ice and spring-overturn in June increased the dissolved Mn concentration tenfold in lake discharge and a concomitant peak in the dissolved Mn concentration was observed in the river. Lake-derived Mn was the dominant source for Mn in the river during this time. Suspended Mn in the river was hosted mainly in detrital particles during flood in May. In mid-June, non-detrital suspended Mn started to accumulate and reached a maximum in late July and early August. The Mn/Al ratio was 25 times higher during this period than during flood in May, suggesting the precipitation of an Mn-oxyhydroxide phase. The precipitation of the non-detrital Mn-rich phase was correlated in time with increased temperature, increased pH and increased concentration of suspended biogenic particles. The precipitation of dissolved Mn was biologically mediated. Sedimentation and mineralisation of the non-detrital Mn phase in river and lake sediments resulted in a steady increase of the dissolved Mn concentration in the river water during autumn.

  • 123.
    Pontér, Christer
    et al.
    Luleå University of Technology.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Burman, Jan-Ola
    Boström, Kurt
    Luleå University of Technology.
    Temporal variations in dissolved and suspended iron and manganese in the Kalix River, northern Sweden1990Ingår i: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 81, nr 1-2, s. 121-131Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Particulate and dissolved Fe and Mn were measured once a week from May to September 1982 in the Kalix River, north Sweden. During winter baseflow the dissolved Fe concentration was 450 mu g 1 super(-1). Early snow-melt discharge increased the concentration slightly but during springflood maximum the concentration decreased to a minimum value of 60 mu g 1 super(-1) in mid-July. Particulate matter in the Kalix River is dominated by Fe which ranges between 14% and 38% of the ashed suspended load, similar to 70-80% of the total Fe load being retained by 0.45- mu m filters. Approximately 10% of particulate Fe can be accounted for by a detrital phase. The particulate Fe/Al ratio showed a mean value of 6.5 which is more than ten times the ratio in mean world river. Particulate Fe showed a peak during early snowmelt and decreased during maximum discharge similar to dissolved Fe. Dissolved Mn concentrations ranged from 1.1 to 53.4 mu m 1 super(-1) with a mean value of 11.2 plus or minus 12.4 mu g 1 super(-1), whereas particulate Mn ranged from 3.1 ti 18.2 mu g 1 super(-1), with a mean concentration of 10.6 plus or minus 4.9 mu g 1 super(-1). During May and June most Mn was transported in the dissolved phase whereas in July and August the particulate fraction dominated. There was a drastic increase in non-detrital particulate Mn with a concomitant decrease in the dissolved fraction in early July with peak values in mid-July and early August. The decrease in dissolved Mn and increase of particulate Mn is probably the consequence of two processes, namely addition of non-detrital particulate Mn to the river, possibly from lakes, and transformation of dissolved Mn to a particulate phase within the river. A combination of increased pH, temperature and particulate Mn triggered the precipitation of dissolved Mn, although the significance of each factor can not be evaluated from this study.

  • 124.
    Porcelli, D.
    et al.
    California Institute of Technology, Pasadena.
    Andersson, P. S.
    Swedish Museum of Natural History.
    Wasserburg, G. J.
    California Institute of Technology, Pasadena.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Baskaran, M.
    Texas A&M University at Galveston.
    The importance of colloids and mires for the transport of uranium isotopes through the Kalix River watershed and Baltic Sea1997Ingår i: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 61, nr 19, s. 4095-4113Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The importance of colloids and organic deposits for the transport of uranium isotopes from continental source regions and through the estuarine environment was investigated in the mire-rich Kalix River drainage basin in northern Sweden and the Baltic Sea. Ultrafiltration techniques were used to separate uranium and other elements associated with colloids > 10 kD and >3 kD from "solute" uranium and provided consistent results and high recovery rates for uranium as well as for other elements from large volume samples. Uranium concentrations in 0.45 μm-filtered Kalix River water samples increased by a factor of 3 from near the headwaters in the Caledonides to the river mouth while major cation concentrations were relatively constant. 234U/238U ratios were high (δ234U = 770-1500) throughout the basin, without showing any simple pattern, and required a supply of 234U-rich water. Throughout the Kalix River, a large fraction (30-90%) of the uranium is carried by >10 kD colloids, which is compatible with uranium complexation with humic acids. No isotopic differences were found between colloid-associated and solute uranium. Within the Baltic Sea, about half of the uranium is removed at low salinities. The proportion that is lost is equivalent to that of river-derived colloid-bound uranium, suggesting that while solute uranium behaves conservatively during estuarine mixing, colloid-bound uranium is lost due to rapid flocculation of colloidal material. The association of uranium with colloids therefore may be an important parameter in determining uranium estuarine behavior. Mire peats in the Kalix River highly concentrate uranium and are potentially a significant source of recoil 234U to the mirewaters and river waters. However, mirewater data clearly demonstrate that only small 234U/238U shifts are generated relative to inflowing groundwater. A simple box model of uranium accumulation in peat and transport through the mire that is compatible with the mire data demonstrates that with efficient removal of uranium from solution, only small shifts in 234U/238U ratios can be generated in mirewater uranium. The measurements and model calculations show that mirewaters are not the primary source of the uranium in the river. Bedrock groundwaters with high 234U/238U ratios and uranium concentrations must be the dominant source of riverine uranium.

  • 125.
    Rehkämper, Mark
    et al.
    ETH Zurich.
    Frank, M.
    ETH Zurich.
    Hein, J.R.
    U.S. Geological Survey.
    Porcelli, D.
    ETH Zurich.
    Halladay, A.
    ETH Zurich.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Liebetrau, V.
    GEOMAR.
    Thallium isotope variations in seawater and hydrogenetic, diagenetic, and hydrothermal ferromanganese deposits2002Ingår i: Earth and Planetary Science Letters, ISSN 0012-821X, E-ISSN 1385-013X, Vol. 197, nr 1-2Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Results are presented for the first in-depth investigation of Tl isotope variations in marine materials. The Tl isotopic measurements were conducted by multiple collector-inductively coupled plasma mass spectrometry for a comprehensive suite of hydrogenetic ferromanganese crusts, diagenetic Fe-Mn nodules, hydrothermal manganese deposits and seawater samples. The natural variability of Tl isotope compositions in these samples exceeds the analytical reproducibility (±0.05‰) by more than a factor of 40. Hydrogenetic Fe-Mn crusts have ε205Tl of +10 to +14, whereas seawater is characterized by values as low as -8 (ε205Tl represents the deviation of the 205Tl/203Tl ratio of a sample from the NIST SRM 997 Tl isotope standard in parts per 104). This 2‰ difference in isotope composition is thought to result from the isotope fractionation that accompanies the adsorption of Tl onto ferromanganese particles. An equilibrium fractionation factor of α1.0021 is calculated for this process. Ferromanganese nodules and hydrothermal manganese deposits have variable Tl isotope compositions that range between the values obtained for seawater and hydrogenetic Fe-Mn crusts. The variability in ε205Tl in diagenetic nodules appears to be caused by the adsorption of Tl from pore fluids, which act as a closed-system reservoir with a Tl isotope composition that is inferred to be similar to seawater. Nodules with ε205Tl values similar to seawater are found if the scavenging of Tl is nearly quantitative. Hydrothermal manganese deposits display a positive correlation between ε205Tl and Mn/Fe. This trend is thought to be due to the derivation of Tl from distinct hydrothermal sources. Deposits with low Mn/Fe ratios and low ε205Tl are produced by the adsorption of Tl from fluids that are sampled close to hydrothermal sources. Such fluids have low Mn/Fe ratios and relatively high temperatures, such that only minor isotope fractionation occurs during adsorption. Hydrothermal manganese deposits with high Mn/Fe and high ε205Tl are generated by scavenging of Tl from colder, more distal hydrothermal fluids. Under such conditions, adsorption is

  • 126.
    Rodushkin, Ilia
    et al.
    ALS Scandinavia AB.
    Pallavicini, Nicola
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Engström, Emma
    ALS Scandinavia AB.
    Sörlin, Dieke
    ALS Scandinavia AB.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Baxter, Douglas C.
    ALS Scandinavia AB.
    Assessment of the natural variability of B, Cd, Cu, Fe, Pb, Sr, Tl and Zn concentrations and isotopic compositions in leaves, needles and mushrooms using single sample digestion and two-column matrix separation2016Ingår i: Journal of Analytical Atomic Spectrometry, ISSN 0267-9477, E-ISSN 1364-5544, Vol. 31, nr 1, s. 220-233Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An analytical procedure allowing multi-elemental analyses and isotope ratio measurements of eight of these (B, Cd, Cu, Fe, Pb, Sr, Tl and Zn) in matrices relevant for bio-monitoring using a single highpressure acid digestion was developed. Method blanks, separation efficiency of matrix elements, repeatability and reproducibility were evaluated using sets of preparation blanks, certified reference materials and duplicate samples prepared and analyzed over a period of several months. The method was used to assess the natural variability of concentrations and isotopic compositions in bio-indicators (tree leaves, needles and mushrooms, over 240 samples) collected mainly from a confined area in North-East Sweden. Ranges found from leaves and needles were compared with data obtained for limited numbers of samples collected in Spain, Italy, France, United Kingdom and Iceland.

  • 127.
    Salifu, Musah
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Aiglsperger, Thomas
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Hällström, Lina
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Martinsson, Olof
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Billström, Kjell
    Department of Geological Sciences, Swedish Museum of Natural History, Frescativagen 40, Box 50007, 104 05, Stockholm, Sweden.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Dold, Bernhard
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Alakangas, Lena
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Strontium (87Sr/86Sr) isotopes: A tracer for geochemical processes in mineralogically-complex mine wastes2018Ingår i: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 99, s. 42-54Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Interpretation of geochemical data based primarily on elemental concentrations often lead to ambiguous results due to multiple potential sources including mineral weathering, atmospheric input, biological cycling, mineral precipitation and exchange processes. The 87Sr/86Sr ratio is however not fractionated by these processes. In this study, Sr isotope (87Sr/86Sr) ratios have been coupled with chemical data of Sr and Rb-bearing minerals, tailings and leachates (water-soluble) to gain insight into the geochemical processes occurring within the Yxsjöberg Cu-W mine tailings, Sweden. The tailings have been exposed to oxidizing conditions resulting in three geochemical zones namely (i) oxidized, (ii) transition and (iii) unoxidized zones. Leachates from the oxidized zone are acidic (pH = 3.6–4.5) and contain elevated concentrations of metals (e.g. Fe, Cu and Zn) and SO4. The low pH has also led to subsequent weathering of most silicates, releasing Al, Ca, Mg and Na into solution. The 87Sr/86Sr ratio in the tailings ranges from 0.84787 to 1.26640 in the oxidized zone, 0.92660–1.06788 in the transition zone, whilst the unoxidized zone has values between 0.76452 and 1.05169. For the leachates, the 87Sr/86Sr ratio ranges from 2.44479 to 5.87552 in the oxidized zone, 1.37404–1.68844 in the transition zone and 1.03697–2.16340 in the unoxidized zone. Mixing (between mineral weathering and atmospheric sources) was identified as the major process regulating the Sr composition of the tailings and leachates. The highly radiogenic signatures of the leachates in the oxidized zone suggests weathering of biotite, K-feldspar and muscovite. Despite the very radiogenic signatures in the oxidized zone, increments in Ca/K ratios, Be, Ce, Tl, Al, Fe and SO4 concentrations in the water-soluble phase were recorded in its lower parts which suggests the dissolution of amphibole, pyroxene, plagioclase, fluorite, gypsum, Al and Fe –(oxy) hydroxides as well as cation exchange by clay minerals. Presence of clay minerals has led to the partial retainment of radiogenic 87Sr/86Sr resulting in increased 87Sr/86Sr in the solid tailings material at these depths. The 87Sr/86Sr ratios of the water-soluble phase in the transition zone is similar to that of helvine and could indicate its dissolution. In the upper part of the oxidized zone, the 87Sr/86Sr ratios and trends of Be, Ca, SO4, Tl and Zn in the water-soluble phase suggest the dissolution of gypsum which precipitated from a leachate with the isotopic signature of helvine. In the lower part of the unoxidized zone, elevated concentrations of W were recorded suggesting scheelite weathering. But the 87Sr/86Sr ratios are higher than that expected from dissolution of scheelite and indicates additional processes. Possible sources include biotite weathering and groundwater. This study reveals that when interpreting geochemical processes in mine waste environments, 87Sr/86Sr should be considered in addition to chemical constituents, as this isotopic tracer offers better insights into discriminating between different solute sources.

  • 128.
    Salvado, Joan A.
    et al.
    Department of Environmental Science and Analytical Chemistry, ACES, Stockholm University.
    Tesi, Tommaso
    Department of Environmental Science and Analytical Chemistry, ACES, Stockholm University.
    Andersson, August
    Department of Environmental Science and Analytical Chemistry, ACES, Stockholm University.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Dudarev, Oleg
    Pacific Oceanological Institute, Russian Academy of Science, Vladivostok, The National Research Tomsk Polytechnic University.
    Semiletov, Igor
    International Arctic Research Center, University of Alaska Fairbanks, University of Alaska, The National Research Tomsk Polytechnic University.
    Gustafsson, Örjan
    Swedish Museum of Natural History, Institute of Applied Environmental Research (ITM), Stockholm University, Department of Environmental Science and Analytical Chemistry, ACES, Stockholm University.
    Organic carbon remobilized from thawing permafrost is resequestered by reactive iron on the Eurasian Arctic Shelf2015Ingår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 42, nr 19, s. 8122-8130Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Given the potential for permafrost carbon (PF/C)-climate feedbacks in the Siberian-Arctic land-ocean system, there is a need for understanding the fate of thawed-out PF/C. Here we show that the sequestration of OC by reactive iron (OC-Fe) ranges between 0.5 and 22% on the Eurasian Arctic Shelf, with higher values in the Kara Sea (KS) (186%) and the Laptev Sea (LS) (144%). The C-14/C-13 signatures of the OC-Fe are substantially older and more terrestrial than the bulk sediment OC in the LS but younger and more dominated by marine plankton sources in the East Siberian Sea (ESS). Statistical source apportionment modeling reveal that reactive iron phases resequestered 155% of thawing PF/C in the LS and 6.45% in the ESS, derived from both coastal erosion of ice complex deposit and thawing topsoil. This Fe-associated trap of PF/C constitutes a reduction of the degradation/outgassing and thus also an attenuation of the PF/C-climate feedback

  • 129.
    Siergieiev, Dmytro
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Widerlund, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lundberg, Angela
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Flow regulation effects on the hydrogeochemistry of the hyporheic zone in boreal rivers2014Ingår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 499, s. 424-436Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    River-aquifer interfaces are essential for ecosystem functioning in terms of nutrient exchange and biological habitat, but are greatly threatened world-wide. This study examined geochemical aspects of river-aquifer interaction in one regulated and one unregulated boreal river in Northern Sweden to determine whether the geochemical functioning of the hyporheic zone is affected by hydrological alterations, e.g. regulated river discharge and river-aquifer connectivity. In the unregulated Kalix River, the hyporheic pore water was well-oxygenated with orthogonal fluxes (≈0.6-0.7 m d-1) and acted as a sink for Fe, Mn, Al, NH4, and Ca, with fractional losses of 95%, 92%, 45%, 31%, and 15%, respectively. A corresponding elevation in the concentrations of these elements in the hyporheic sediment was observed, with higher saturation indices of Fe-, Mn-, and Al-bearing secondary minerals in hyporheic waters. In the regulated Lule River, hydraulic connectivity at the river-aquifer interface was altered by the presence of a clogging layer (0.04 m d–1). In addition, the river discharge oscillated daily, severely reducing exchange flows across the riverbed (<0.01 m d-1). As a result, the hyporheic pore water was suboxic, with elevated concentrations of filtered Fe and Mn (fractional increase of ≈3700% and ≈2500%, respectively) and other solutes (NH4, Si, S, Ca). A conceptual model revealed functional differences between geochemical features of the hyporheic zone of regulated and unregulated rivers. Overall, the results showed that hyporheic processes are altered along regulated rivers, with resulting impacts on the geochemistry of riverine, riparian and related marine ecosystems.

  • 130.
    Siergieiev, Dmytro
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Widerlund, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lundberg, Angela
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Drugge, Lisbeth
    Collomp, Magali
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Öhlander, Björn
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Impact of Hydropower Regulation on River Water Composition in Northern Sweden2014Ingår i: Aquatic geochemistry, ISSN 1380-6165, E-ISSN 1573-1421, Vol. 20, nr 1, s. 59-80Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Using hydrogeochemical analysis of two large boreal rivers (pristine Kalix and hydropower regulated Lule) discharging into the Gulf of Bothnia, the major impacts of regulation on water discharge, element transport, and their seasonal redistribution have been assessed. The pre-regulation hydrogeochemical features were assumed to be similar for the two rivers. For the Lule River, the average maximum runoff was almost halved, while the average minimum was tripled as a result of the regulation. The fraction of winter transport of total organic carbon (TOC), Fe, Si, suspended Mn and P in the Lule River was, according to a conservative estimate, two to three times higher than in the pristine river. Longer residence time in the Lule River delayed arrival of the suspended Mn peak and dissolved Si decline to the river mouth. During summer, the suspended C/N ratio in the regulated river was 10-20 compared to <10 for the pristine, suggesting presence of predominantly old organic material. This was supported by a virtually constant suspended P/Fe ratio throughout the year in the Lule River, indicating low abundance of phytoplankton. TOC varied irregularly in the Lule River suggesting temporal disconnection between the river and the upper riparian zone. The disappearance of the spring flow maximum, a shift of element transport from spring to winter, and supply of mainly old organic material during the vegetation growth season may have a pronounced impact on the ecosystem of the Gulf of Bothnia and the river itself.

  • 131.
    Suteerasak, Thongchai
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik. Faculty of Technology and Environment, Prince of Songkla University, Thailand.
    Elming, Sten-Åke
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Possnert, Göran
    Department of Physics and Astronomy, Uppsala University.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Widerlund, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Deposition rates and 14C apparent ages of Holocene sediments in the Bothnian Bay of the Gulf of Bothnia using paleomagnetic dating as a reference2017Ingår i: Marine Geology, ISSN 0025-3227, E-ISSN 1872-6151, Vol. 383, s. 1-13Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Three 6-m-long cores of sediments were collected in the northern, middle and southern part of the Bothnian Bay. The sediments were dated by paleomagnetic dating techniques, constrained by magnetic properties and geochemical data. The results indicate the ages of the sediments in the bottom part of the cores in the northern, middle and southern parts of the Bothnian Bay to be approximately 5300 years BP, 5350 years BP and 3500 years BP, respectively. The deposition rate calculated from the estimated ages at various depths show that the deposition rate was generally in the range 0.5–1.5 mm/year but it was higher in the southern part than in the middle and northern parts of the bay. There was a significant increase in the deposition rate at ca 2200 years BP, recorded in all three cores, a rate varying between 2.47 and 3.07 mm/year and lasting until ca 1840 years BP. A proposed constant uplift rate of the crust during the period ca 5500 years BP to present is thus not reflected by a constant deposition rate. The peaks in deposition rates at ca 2200–1840 years BP were followed by a decrease in salinity. This phenomenon is suggested to be caused by crustal uplift, with a threshold being formed in the southern part of the bay, thereby increasing the reactivation of bottom sediments and reducing the inflow of brackish water from the Bothnian Sea. The14C ages of the sediments reveal differences in age compared with the paleomagnetic ages. In the southern core, the 14C ages are ca 1350 years older, and in the north, the age offset is mixed. The reactivation and re-deposition of sediments is argued to be the reason for the apparent 14C age differences. This finding demonstrates that 14C cannot be used for the dating of Bothnian Bay sediments unless the radiocarbon age offset has been determined.

  • 132.
    Walve, Jakob
    et al.
    Department of Ecology, Environment and Plant Sciences, Stockholm University.
    Gelting, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Trace metals and nutrients in Baltic Sea cyanobacteria: Internal and external fractions and potential use in nitrogen fixation2014Ingår i: Marine Chemistry, ISSN 0304-4203, E-ISSN 1872-7581, Vol. 158, s. 27-38Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Even though the availability of trace metals influences nitrogen fixation and growth of cyanobacteria, field data on their cellular metal composition are scarce. In this study, contents of Al, Ti, V, Mn, Fe, Co, Ni, Cu, Zn, Mo, Cd, and the major elements C, N, P and Si were studied in filamentous, nitrogen-fixing cyanobacteria sampled over the growth season March-October at two locations in the Baltic proper (years 2004 and 2007) and one location in the Bothnian Sea (2006). The Al and Ti contents indicated that lithogenic Fe was an important Fe fraction associated with Nodularia spumigena, but not with Aphanizomenon sp. Treatment with an oxalate-EDTA solution indicated that less than 5% of total Fe was adsorbed as oxides, but relatively high adsorbed fractions were found for Mn and Cu. Despite large variation in biomass and dissolved Fe concentrations, the Fe:C ratio of Aphanizomenon was highly consistent within years and across sampling stations (76 ± 13 μmol mol- 1 C, average ± 1SD), indicating growth controls other than Fe. Species-mixed samples corrected for lithogenic metals indicate similar Fe content in Nodularia as in Aphanizomenon. Calculations based on the use efficiency of Mo for N2 fixation indicates that most Mo in Nodularia and at least a third of the Mo in Aphanizomenon is used in nitrogenase, corresponding to 5-24% of the Fe content. The high Ni content suggests excess storage or extensive use in enzymes such as Ni superoxide dismutase or in Fe-dependent Ni-hydrogenases. The trace metal composition of the investigated Baltic cyanobacteria was similar to that reported for the oceanic genus Trichodesmium, suggesting common physiological requirements of these filamentous nitrogen-fixing cyanobacteria.

  • 133.
    Wasserburg, GJ
    et al.
    California Institute of Technology, Pasadena.
    Andersson, Per
    Swedish Museum of Natural History.
    Chen, J H
    Papanastassiou, D A
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Isotopic study of estuarine environments: the Baltic Sea and its riverine inputs1994Ingår i: Abstracts with programs (Geological Society of America), ISSN 0016-7592, Vol. 26, nr 7, s. 19-Artikel i tidskrift (Övrigt vetenskapligt)
  • 134.
    Widerlund, Anders
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Early diagenesis of arsenic in sediments of the Kalix River estuary, northern Sweden1995Ingår i: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 125, nr 3-4, s. 185-196Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Solid-phase As, Fe, Mn, S and Al and pore-water total As, Fe, Mn and S have been determined for two cores from the Kalix River estuary. At the same station, the depositional flux of arsenic was measured sediment traps. Fe(III)-oxides persist in the anoxic zone of the sediment and act as a carrier for arsenic down to depths of 10-15 cm. The release of arsenic into the pore water is controlled by the reduction/dissolution of these oxides. As a result, internal cycling of arsenic, i.e. upward diffusion in pore water, re-adsorption onto Fe(III)-oxides in the oxidized surface layer and reburial occurs in the uppermost 10-15 cm. At the base of the arsenic cycling zone, solid-phase arsenic maxima (160-170 μg g-1) of probable diagenetic origin occur. The quantity of arsenic diffusing back towards the oxidized surface layer (2.2 μg cm-2 yr-1 As) is close to 75% of the quantity of arsenic being deposited due to sedimentation (2.9 μg cm-2 yr-1 As). However, a mass balance for the surface layer indicates that re-adsorption of arsenic onto Fe(III)-oxides may effectively prevent diffusion of dissolved arsenic back into the overlying water column. It is concluded that the interpretation of sedimentary arsenic profiles may be severely complicated due to post-depositional migration of arsenic

  • 135.
    Widerlund, Anders
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Redox cycling of iron and manganese in sediments of the Kalix River estuary, northern Sweden1996Ingår i: Aquatic geochemistry, ISSN 1380-6165, E-ISSN 1573-1421, Vol. 2, nr 2, s. 185-201Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Iron and manganese redox cycling in the sediment - water interface region in the Kalix River estuary was investigated by using sediment trap data, pore-water and solid-phase sediment data. Nondetrital phases (presumably reactive Fe and Mn oxides) form substantial fractions of the total settling flux of Fe and Mn (51% of Fetotal and 84% of Mntotal). A steady-state box model reveals that nondetrital Fe and Mn differ considerably in reactivity during post-depositional redox cycling in the sediment. The production rate of dissolved Mn (1.6 mmol m-2 d-1) exceeded the depositional flux of nondetrital Mn (0.27 mmol m-2 d-1) by a factor of about 6. In contrast, the production rate of upwardly diffusing pore-water Fe (0.77 mmol m-2 d-1) amounted to only 22% of the depositional flux of nondetrital Fe (3.5 mmol m-2 d-1). Upwardly diffusing pore-water Fe and Mn are effectively oxidized and trapped in the oxic surface layer of the sediment, resulting in negligible benthic effluxes of Fe and Mn. Consequently, the concentrations of nondetrital Fe and Mn in permanently deposited, anoxic sediment are similar to those in the settling material. Reactive Fe oxides appear to form a substantial fraction of this buried, non-detrital Fe. The in-situ oxidation rates of Fe and Mn are tentatively estimated to be 0.51 and 0.16-1.7 mol cm-3 d-1, respectively

  • 136.
    Widerlund, Anders
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Roos, Per
    Lund University.
    Gunneriusson, Lars
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Industriell miljö- och processteknik.
    Ingri, Johan
    Holmström, Henning
    Envipro Miljöteknik AB, Linköping.
    Early diagenesis and isotopic composition of lead in Lake Laisan, northern Sweden2002Ingår i: Chemical Geology, ISSN 0009-2541, E-ISSN 1872-6836, Vol. 189, nr 3-4, s. 183-197Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Water column (dissolved/suspended phase, sediment traps) and sediment data (pore-water, solid-phase sediment) were combined with stable Pb and 210Pb isotope data to trace the early diagenetic behaviour and geochemical cycling of Pb in Lake Laisan, a lake which has received large quantities of anthropogenic Pb since the early 1940s. Early diagenetic remobilisation of Pb is indicated by a subsurface pore-water Pb maximum (120 μg l-1) in the oxic surface layer of the sediment, where the solid-phase Pb concentration is 3400-4600 μg g-1. The remobilisation of Pb appears to be caused by a pH-controlled desorption of Pb from solid-phase sediment, which is consistent with a model describing surface complexation of Pb(II) on hydrous goethite surfaces. The diffusive Pb flux from the subsurface pore-water maximum towards the sediment surface (36 μg cm-2 year-1) exceeds the depositional Pb flux (8.6 μg cm-2 year-1) by approximately a factor of four, indicating that Pb is highly mobile in the sediment. Stable Pb isotope data and a mass balance calculation suggest that Pb diffusing upwards is, to a large extent, trapped in the surface sediment. Lead that may diffuse into the slightly alkaline lake water appears to be efficiently sorbed to suspended particulate matter, resulting in low dissolved Pb concentrations in the water column (0.040-0.046 μg l-1). Sorption of Pb to suspended particulate matter is consistent with the elevated suspended particulate Pb concentrations in the hypolimnion (3800-4000 μg g-1), and the fact that the stable Pb isotopic compositions of suspended matter and pore-water are similar.

  • 137.
    Wortberg, Katharina
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Conrad, Sarah
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Andersson, Per S.
    Department of Geosciences, Swedish Museum of Natural History.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Strontium isotopes: A tracer for river suspended iron aggregates2017Ingår i: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 79, s. 85-90Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The Kalix River shows distinct temporal variations in the Sr-isotope ratio in filtered water (0.726–0.732). During base flow in winter the 87Sr/86Sr ratio is on average 0.730. When discharge increases and peaks during spring flood the 87Sr/86Sr ratio shows the most radiogenic (0.732) values. The temporal variations in the 87Sr/86Sr ratio in the Kalix River can be explained by mixing of water from the woodlands and the mountain areas.

    During high water discharge in May the 87Sr/86Sr ratios are more radiogenic in the suspended phase (1 kDa - 70 μm) compared to the truly dissolved phase (<1 kDa). The difference in 87Sr/86Sr ratio between the two phases (Δ 87Sr/86Sr) is linearly correlated with the suspended iron concentration. During spring flood Sr and Fe derived from an additional source, reach the river. Deep groundwater has a more radiogenic 87Sr/86Sr isotope ratio than the Kalix River during spring flood and thus, represents a possible source for the suspended Fe and the associated Sr. Strontium can be coprecipitated with and adsorbed to different types of Fe aggregates. We propose that the Sr-isotope ratio in the suspended phase reflects the isotopic composition of the water at the interface between anoxic groundwater and oxic stream water in the riparian zone, where the Fe aggregates are formed. These particles dominate the suspended phase in the river and the mixing with mountain waters, poor in Fe, produces the difference in the isotopic signature.

    The different signatures in suspended and truly dissolved fraction indicate that these aggregates are relatively stable during stream-river transport. As such the 87Sr/86Sr can be used to trace the origin of the non-detrital suspended phase.

  • 138.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Drugge, L.
    Widerlund, Anders
    Ingri, Johan
    Changed transport of weathering products after river regulation: the Lule River, northern Sweden2004Ingår i: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 68, nr 11, s. 31-Artikel i tidskrift (Övrigt vetenskapligt)
  • 139.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Forsberg, Jerry
    Österlund, Helene
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ecke, Frauke
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Alakangas, Lena
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Fractionation of trace metals in a contaminated freshwater stream using membrane filtration, ultrafiltration, DGT and transplanted aquatic moss2012Ingår i: Geochemistry: Exploration, Environment, Analysis, ISSN 1467-7873, E-ISSN 2041-4943, Vol. 12, nr 4, s. 303-312Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Four metal speciation and fractionation techniques – DGT (diffusive gradients in thin films), 1-kDa ultrafiltration, 0.22-µm membrane filtration and aquatic moss – were simultaneously applied to a small, contaminated freshwater stream in northern Sweden to investigate differences and similarities between the methods regarding trace metal speciation and their dependence on geochemical water properties. The investigated metals comprise Al, Cd, Co, Cu, Fe, Mn, Ni, and Zn. The normal DGT devices with Chelex cation exchanger were used. Shoots from the aquatic moss Fontinalis antipyretica L ex Hedw. were collected in a non-polluted brook and transplanted to the sampling site for exposure. It was evident that 0.22-µm membrane filtration, 1-kDa ultrafiltration and DGT generally measured different metal fractions where

  • 140.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Forsberg, Jerry
    Österlund, Helene
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ecke, Frauke
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Alakangas, Lena
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Speciation of trace metals in a contaminated stream at the Laver mine by using membrane filtration, ultrafiltration, DGT and transplanted aquatic moss2011Konferensbidrag (Refereegranskat)
  • 141.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Land, Magnus
    Andersson, P.S.
    Schönberg, H.
    Fractionation of Sm-Nd isotopes during weathering of till1998Ingår i: Mineralogical magazine, ISSN 0026-461X, E-ISSN 1471-8022, Vol. 62A, s. 1104-1105Artikel i tidskrift (Övrigt vetenskapligt)
  • 142.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Ponter, C.
    Geochemistry of till weathering in the Kalix river watershed, northern Sweden1990Ingår i: Chemical Weathering under Field Conditions: reports from a Nordic seminar, 27-28 September 1990, Wik, Uppsala / [ed] Kaj Rosen, Sveriges Lantbruksuniversitet, 1990, s. 1-18Konferensbidrag (Refereegranskat)
  • 143.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Pontér, Christer
    Luleå tekniska universitet.
    Lead isotopes as tracers of environmental pollution from mining industries1991Ingår i: Abstracts: [2nd International Symposium on Environmental Geochemistry], including 3rd International Symposium on Environmental Geochemistry and Health and 9th European Meeting of The Society for Environmental Geochemistry and Health, 16-19 September 1991, Uppsala, Sweden / [ed] O Selinus, Uppsala: Sveriges Geologiska Undersökning , 1991Konferensbidrag (Övrigt vetenskapligt)
  • 144.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Ingri, Johan
    Pontér, Christer
    Lead isotopes as tracers of lead pollution from various sources: an example from northern Sweden1993Ingår i: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 8, nr Suppl. 2, s. 67-70Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The surface sediments in the central Bothnian Bay are contaminated with antropogenic Pb. Preindustrial sources of the Pb pollution are anthropogenic atmospheric Pb, where the main Pb source is combustion of gasoline, and ore from the Laisvall mine which is processed in the smelter Rönnskärsverken. Because the Pb isotope composition of these possible sources are known, an attempt was made to trace the origin of the antropogenic Pb by studying the Pb isotope composition of sediments. The results show unequivocally that Laisvall Pb is not the source of the pollution. The enrichment of Pb in surface sediments is caused by atmospheric deposition of Pb additives from gasoline. Lead emitted from Rönnskärsverken is deposited relatively close to the smelter, and has not reached central Bothnian Bay in traceable amounts.

  • 145.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Land, Magnus
    Stockholms Universitet.
    Ingri, Johan
    Mobility and transport of Nd isotopes during weathering of till in a boreal forest2007Ingår i: Geochimica et Cosmochimica Acta, ISSN 0016-7037, E-ISSN 1872-9533, Vol. 71, nr 15S, s. A732-Artikel i tidskrift (Övrigt vetenskapligt)
  • 146.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Land, Magnus
    Mistra Council for Evidence-based Environmental Management (EviEM), The Royal Swedish Academy of Sciences.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Widerlund, Anders
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Mobility and transport of Nd isotopes in the Vadose zone during weathering of granitic till in a boreal forest2014Ingår i: Aquatic geochemistry, ISSN 1380-6165, E-ISSN 1573-1421, Vol. 20, nr 1, s. 1-17Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    There is a broad correlation between the εNd values for rivers (including both the water and the particulate material it carries) and the age of the source terrain. This paper presents Nd isotope distribution data for soil, soil water, groundwater, and stream water samples gathered in a small catchment in northern Sweden. The results show that the release of Nd and Sm from boreal forests into streams and, eventually, into the oceans is more complicated than previously realized. The weathering of till causes changes in both the Nd isotopic composition and Sm/Nd ratios. Both the Sm/Nd ratio and εNd were higher in strongly weathered soils horizons than in less weathered till, since minerals with high Sm/Nd ratios were, on average, more resistant to weathering than those with low Sm/Nd ratios. In contrast to the situation for the main minerals and the major elements, the weathering of rare earth elements (REE) was not restricted to the E-horizon: the measured REE concentrations continued to increase with depth in the C-horizon. In addition, REE released by weathering in the upper parts of the soil profile were partly secondarily retained at deeper levels. Therefore, the dissolved Nd released by weathering in the upper soil horizons was trapped and did not enter the groundwater directly. Rather, the Nd in the groundwater largely originated from weathering within the groundwater zone. However, this was not the only source of Nd in the stream water. The Nd isotope composition and Sm/Nd ratio were determined by the mixing between of Nd and Sm in the groundwater and REE-carrying organic material washed out of the soil profile. The groundwater close to the stream reaches the upper soil horizons during high discharge events such as snowmelts, and organic matter carrying Nd and Sm is washed out of the soils and thus released into the stream. Therefore, the Nd exported from catchment is derived from both the weathering within the groundwater zone, and the organic matter washed out from the soil. If longer timescales with more advanced weathering stages in the groundwater zone are considered, it cannot be ruled out that there will be a shift towards more radiogenic values in the exported Nd. Recorded shifts in the Nd isotopic composition in the ocean may thus not only reflect changed source regions, but also the weathering history of the same source region

  • 147. Öhlander, Björn
    et al.
    Land, Magnus
    Luleå tekniska universitet.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Widerlund, Anders
    Mobility of rare earth elements during weathering of till in northern Sweden1996Ingår i: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 11, nr 1-2, s. 93-99Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Continuous, volume-controlled sampling from the surface down to a depth of 130 cm was conducted at two stations on weathered till (typic haplocryods). All the samples were analysed for major and trace elements including the rare earth elements (REE). Eight thousand seven hundred years of weathering since the glacial ice left the area, has resulted in a strong depletion of REE in the E-horizon. This loss decreases as atomic number increases, so that 80-85% of the La and 54-60% of the Yb have been lost. Europium has been lost to a greater degree than have the neighbouring elements. Possible explanations for the release of REE are: weathering of common silicates such as hornblende and epidote (and plagioclase in the case of Eu); weathering of apatite; weathering of rare but REE-rich minerals such as allanite and monazite; and release of REE adsorbed on clay minerals. Further studies on various size fractions and minerals are needed to quantify the importance of the various possible mechanisms of REE release. The release of REE continues within and below the Bs1-horizon, but the results from one station show that light REE can be enriched in the Bs1-horizon. This secondary enrichment could be caused by adsorption on secondary oxy-hydroxides, on clay minerals or on organic material. However, the net result of the weathering is that all REE have been released to the groundwater.

  • 148.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Nordblad, Fredrik
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Lax, Kaj
    Geological Survey of Sweden.
    Ecke, Frauke
    Swedish University of Agricultural Sciences, Department of Aquatic Sciences and Assessment.
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Biogeochemical mapping of stream plants to trace acid sulphate soils: A comparison between water geochemistry and metal content in macrophytes2014Ingår i: Geochemistry: Exploration, Environment, Analysis, ISSN 1467-7873, E-ISSN 2041-4943, Vol. 14, nr 1, s. 85-94Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The efficiency of biogeochemical mapping for identifying acid sulphate soils (AS soils) was studied by sampling and analysing water, transplanted aquatic moss (Fontinalis antipyretica) and leaves of the vascular plant Calamagrostis purpurea at two sites in a stream in northern Sweden with AS soils in its drainage area. One upstream sampling station (Mårtsmarken) was situated in an area dominated by till, and a downstream station (Persraningen) was situated in an area where AS soils are common. Metal contents in F. antipyretica and C. purpurea at these sites were compared to those in water (both unfiltered samples, and samples subjected to 0.22 μm membrane filtration and 1 kDa ultrafiltration to obtain data on metal speciation and its effects on uptake). Oxidation of sulphides with associated increases in acidity and release of metals were clearly reflected by differences in the water samples. At Persraningen the pH was lower than at Mårtsmarken, and the unfiltered concentrations of Al, Ca, Cd, Co, Cu, K, Mg, Mn, Ni, P, S, Sr, Y and Zn were higher. At the upstream station, Mårtsmarken, the suspended fraction was an important carrier of Fe and P, and the colloidal concentrations were higher than or similar to the dissolved concentrations for all determined elements except Na and K. At Persraningen the low pH resulted in changes of speciation, so that the dissolved concentrations were higher than the colloidal concentrations for most elements. For Al, As, Cr, Cu, Pb and Y, the dissolved and colloidal concentrations were similar. For Fe, the colloidal concentration was usually higher than the dissolved concentration, and suspended Fe was detected. Aluminium, Cr, Cu, Fe and Y concentrations were significantly higher in Fontinalis antipyretica at Persraningen than at Mårtsmarken. In addition, concentrations of Al and Fe in C. purpurea were significantly higher at Persraningen. Our results highlight the potential of biogeochemical mapping for predicting the occurrence of AS soils. A limitation is the strong pH dependence of the uptake of metals in the aquatic mosses resulting in that only a few of the elements typically occurring at high concentrations in waters draining AS soils are enriched in the macrophytes. A combination of maps showing both absolute concentrations and elemental ratios would be useful for this, including not only ratios of previously suggested utility (e.g. Y:Pb and Ni:Pb), but also others, such as Y:Ca, Al:Ca, Cu:Ca, Y:Mg, Al:Mg and Cu:Mg. © 2014 AAG/The Geological Society of London.

  • 149.
    Öhlander, Björn
    et al.
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Widerlund, Anders
    Holmström, Henning
    Ingri, Johan
    MiMi – Field studies and characterisation: state-of-the-art-report1998Rapport (Övrigt vetenskapligt)
  • 150. Österlund, Helene
    et al.
    Chlot, Sara
    Faarinen, Mikko
    ALS Laboratory Group, Luleå.
    Widerlund, Anders
    Rodushkin, Ilya
    Ingri, Johan
    Luleå tekniska universitet, Institutionen för samhällsbyggnad och naturresurser, Geovetenskap och miljöteknik.
    Baxter, Douglas
    Simultaneous measurements of As, Mo, Sb, V and W using a ferrihydrite diffusive gradients in thin films (DGT) device2010Ingår i: Analytica Chimica Acta, ISSN 0003-2670, E-ISSN 1873-4324, Vol. 682, nr 1-2, s. 59-65Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The ferrihydrite-backed DGT (diffusive gradients in thin films), recently developed for arsenic and phosphate measurements was, for the first time, characterized with respect to molybdate, antimonate, vanadate and tungstate determination. Arsenate was included in the characterization to allow comparison with literature data and thus provide quality control of the measurements. In addition to laboratory experiments, field measurements were carried out in a natural stream in northern Sweden affected by mine drainage. It was shown that ferrihydrite-DGT is suitable for simultaneous determination of labile arsenic, molybdate, antimonate, vanadate and tungstate over a wide pH range. Diffusion coefficients were estimated using two different methods; diffusion cell and direct uptake to DGT devices in synthetic solutions. Estimations of the coefficients using the direct uptake method were performed between pH 4 and 8. The results from the two methods agreed well irrespective of pH, except for molybdate and antimonate that showed decreased values at pH 8. Adsorption of the analytes to ferrihydrite gel discs was rapid at all pH values. However, there was a tendency toward lower adsorption affinity for antimonate compared to the other anions. 100% recovery of accumulated analytes was achieved through complete dissolution of the ferrihydrite adsorbent using 1.4 mol L-1 HNO3 with 0.1 mol L-1 HF. From field sampling it was concluded that the opportunities for accurate antimonate and molybdate determination decrease at pH ≥8.7. DGT labile concentrations were generally lower than dissolved concentrations. Relatively lower DGT concentrations, compared to dissolved (<0.45 μm), were observed under a period when ferric oxide precipitations were detected on the DGT protective filter.

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