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  • 1.
    Andrén,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Ger alla ALI-analyser ALI – monomert oorganiskt aluminium?2007In: Norsk-Svensk Konferanse om forsurning og kalking 2007: 18-20 september, 2007Conference paper (Other (popular science, discussion, etc.))
  • 2.
    Andrén, C
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Bottenfauna och kiselalger i rinnande vatten inom IKEU-projektet. Redovisning av delprojekt 2b.C&D inom IKEU-utvärderingen 20082008Report (Other academic)
  • 3.
    Andrén, C
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Jarlman, A.
    Benthic diatoms as indicators of acidity in streams2008In: Fundam. Appl. Limnol., Vol. 173, p. 237-253Article in journal (Refereed)
  • 4.
    Andrén, Cecilia M.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Toxicity of Inorganic Aluminium in Humic Streams2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Aluminium (Al) has been recognised as a main toxic factor alongside pH in acidified water ecosystems. The toxic effect of Al has been attributed to inorganic Al (Ali), though there are few in situ studies in ambient humic waters which are the focus of this thesis.

    The aim was to estimate Ali toxicity and thus also Ali concentrations in Swedish humic streams. Subsequently it is necessary to analyse Ali correctly, which was studied by modelling and method intercalibrations. The hypothesis was that the effect of Ali could be followed via physiological effects and Al accumulation, as well as by mortality. Toxicity was studied by in stream exposures of brown trout (Salmo trutta L.) and two salmonid prey organisms (Gammarus pulex and Baetis rhodani) during spring flood.

    The modelling of the Ali fraction was performed using monitoring data covering all of Sweden with satisfactory results. The essential variables for Ali modelling were determined; Al, DOC, pH and F, while Fe, Ca and Mg had less effect. The automated analytical procedure for Ali (with cation exchange followed by complexation with pyrocatechol violet) was modified and validated and showed to be the preferred method for laboratory analyses.

    To avoid detrimental effects for brown trout Ali should be <20 µg/L and pH >5.0; mortality was high when the Ali was above 50 µg/L. The invertebrates were more sensitive, as mortalities occurred at pH <6.0 and Ali >15 µg/L for G. pulex, and at pH <5.7 and Ali >20 µg/L for B. rhodani. It is prudent to use a wide view and let the most sensitive species set the tolerance limits; a pH above 5.7-6.0 and Ali below 15-20 µg/L allows the stream ecosystems to thrive.

    Today, as waters are recovering from acidification, the aim of mitigating liming is to carefully adjust dosage to avoid suboptimal water quality. The thresholds found in this thesis can be used to efficiently but carefully decrease liming, as both Ali and pH levels have to be balanced to sustain the recovering aquatic biota.

  • 5.
    Andrén, Cecilia M.
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Eriksson Wiklund, Ann-Kristin
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Response of Gammarus pulex and Baetis rhodani to springtime acid episodes in humic brooksManuscript (preprint) (Other academic)
    Abstract [en]

    Although the acid load has decreased throughout Scandinavia, episodic acidification continues to affect stream biology by temporarily decreasing pH levels and mobilising aluminium. These events are becoming more common as climate change renders more frequent and intense storm floods. The transient acidity can reduce fish populations, but fish food resources can also be impaired because macro-invertebrates are affected. In this in-stream study, two salmonid prey organisms (Gammarus pulex and Baetis rhodani) were exposed to snowmelt in six humic brooks with a natural gradient of pH and inorganic monomeric Al (Ali). We hypothesise that there are thresholds for acid toxicity that can be defined by mortality and changes in body elemental content. Mortality was observed and the whole body content of base cations (BC, i.e., Ca, Mg, Na and K) and metals (Al, Fe, Zn and Mn) were determined. Both species began to die and the total bodily BC content decreased as the pH levels decreased and the Ali concentrations increased. In contrast to what has been observed for fish gills, no accumulation of Al was observed. The invertebrate body Na content decreased when the pH level decreased, which indicated that the osmoregulation in both species was affected. The Ca content in G. pulex and the Mg content in B. rhodani diverged from the general BC-pattern by increasing when the pH level decreased. The mortality increased drastically at pH <6.0 and Ali >15 μg/L for G. pulex and at pH <5.7 and Ali >20 μg/L for the somewhat less sensitive B. rhodani. Although Ali is tightly correlated to pH, the local Al availability in soil and bedrock also affect the Al release and toxic Ali episodes can consequently arise in some catchment areas. The estimated values can be used as water quality thresholds to adjust lime dose because both Ali and pH levels have to be balanced to prevent harm in recovering stream ecosystems.

  • 6.
    Andrén, Cecilia M.
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Eriksson Wiklund, Ann-Kristin
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Response of Gammarus pulex and Baetis rhodani to springtime acid episodes in humic brooks2013In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 463, p. 690-699Article in journal (Refereed)
    Abstract [en]

    While chronic acidification of water bodies has been steadily decreasing, episodic acidification continues to affect stream biology by temporarily decreasing pH and mobilizing aluminum. These events are becoming more common as climate change renders more frequent and intense storms and flooding. Throughout Scandinavia, the effects of acidification have been mitigated by liming since the 1980s, but remediation efforts can now be reduced. While transient acidity may reduce fish populations, also other species in streams are affected. In this in-stream study, two macro-invertebrates (Gammarus pulex and Baetis rhodani), both known as salmonid prey organisms, were exposed to snowmelt in six humic brooks with a natural gradient of pH and inorganic monomeric Al (Al-i). We hypothesize that acid toxicity thresholds can be defined using lethal (mortality) and sublethal (changes in body elemental content) metrics. Periodic observations were made of mortality and whole body concentrations of base cations (BC: Ca, Mg, Na and K) and metals (Al, Fe, Zn and Mn). Mortality increased dramatically at pH < 6.0 and Al-i > 15 mu g/L for G. pulex and at pH < 5.7 and Al-i > 20 mu g/L for B. rhodani. No accumulation of Al was found. The invertebrate body Na concentration decreased when pH dropped, suggesting that osmoregulation in both species was affected. In contrast to general BC pattern, Ca concentration in G. pulex and Mg concentration in B. rhodani increased when pH decreased. Although Ali strongly correlates to pH, the Al composition of soil and bedrock also influences Al availability, potentially contributing to toxic Al; episodes. The estimated values calculated in this study can be used to improve water quality criteria and as thresholds to adjust doses of lime compared to old recommendations in ongoing liming programs. Such adjustments may be critical since both Ali and pH levels have to be balanced to mitigate damage to recovering stream ecosystems.

  • 7.
    Andrén, Cecilia M.
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Kroglund, Frode
    Norwegian Institute for Water Research (NIVA), Grimstad , Norway.
    Teien, Hans-Christian
    Agricultural University of Norway, Department of Plant and Environmental Sciences, Aas, Norway.
    Controlled exposure of brown trout to humic water limed to different pH and inorganic aluminium concentrations2006In: Verhandlungen / Internationale Vereinigung für Theoretische und Angewandte Limnologie, ISSN 0368-0770, Vol. 29, p. 1548-1552Article in journal (Refereed)
    Abstract [en]

    Fish that accumulated more than 800 μg Al/g dw gill and 900 μg Fe/g dw gill died at pH 4.6 but survived at higher pH. Fish experienced severe physiological responses when gill-Al exceeded 600 μg Al/g. Fish having less than 200 μg Al/g had a satisfactory health status based on the variables monitored. The observation of between-strain variation response suggests that some variation in the dose-response model must considered or that stream specific water quality guidelines needs to be developed.The fish responses and gill-Al can be translated to water quality criteria. Acceptable water quality over a 7-day period for 11-cm yearlings was obtained in water having < 60 μg Ali/L. Following liming, this level was achieved within 15 min at a pH target of 6.0,within 140 min at a pH target of 5.5 (see companionpaper, TEIEN et al. 2005). However care should betaken when applying these criteria to streams, as they will not protect more sensitive life stages at reproductionand hatching.

  • 8.
    Andrén, Cecilia M.
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Rydin, Emil
    Uppsala universitet, Institutionen för ekologi och genetik .
    Toxicity of inorganic aluminium at spring snowmelt—In-stream bioassays withbrown trout (Salmo trutta L.)2012In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 437, p. 422-432Article in journal (Refereed)
    Abstract [en]

    Although the acid load has decreased throughout Scandinavia, acidic soils still mobilise aluminium (Al) thatis harmful to brown trout. We hypothesise that there are thresholds for Al toxicity and that the toxicity can betraced from the water content to gill accumulation and the consequential physiological effects. During snowmelt,yearlings were exposed to a gradient of pH and inorganic monomeric Al (Ali) in humic streams to studythe toxic effects and mortality. Gill Al and physiological blood analyses [haemoglobin (Hb), plasma chloride(P-Cl) and glucose (Glu)] were measured. As the water quality deteriorated, Al accumulated on the gills; Hband Glu increased; P-Cl decreased, and mortality occurred. Moribund fish had significantly increased gill Aland Hb, suggesting that respiratory disturbances contributed to mortality. Decreased P-Cl and plasmaavailability indicated an ion regulatory disturbance and possibly circulatory collapse. Ali should be lessthan 20 μg/L, and pH higher than 5.0, to sustain healthy brown trout populations. These thresholds can beused to fine-tune lime dose, as both Ali and pH levels have to be balanced to prevent harm in the recoveringaquatic biota. Although Al is tightly linked to pH, local variation in Al availability in soil and bedrock affectsthe Al release and subsequent toxic Ali episodes in some catchment areas.

  • 9.
    Andrén, Cecilia M
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Rydin, Emil
    Uppsala universitet, EBC, Department of Limnology .
    Which aluminium fractionation method will give true inorganic monomeric Al results in fresh waters (not including colloidal Al)?2009In: Journal of Environmental Monitoring, ISSN 1464-0325, E-ISSN 1464-0333, Vol. 11, no 9, p. 1639-1646Article in journal (Refereed)
    Abstract [en]

    Aluminium solubility and toxicity increase with acidification. There is no standardized analytical method for the determination of inorganic monomeric Al (Al(im)), which is the form that causes toxicity to fish. Separation by cation exchange is commonly combined with other analytical methods, such as complexation with pyrochatechol violet (PCV) or 8-hydroxyquinoline (HQ) and total quantification using graphite furnace or inductively-coupled plasma emission. Data from 14 laboratories were obtained for a dilution series of Al(im) samples; the results of the Al(im) analysis were statistically evaluated. The Al(im) levels were altered through pH, which was controlled by the addition of calcium hydroxide. Confounding parameters such as total organic carbon (TOC) or fluoride (F) were controlled. The total determination and HQ methods yielded significantly higher Al(im) concentrations than the PCV method. Pretreatment by passage through a 0.45 microm filter and pH-adjustment of the ion exchange column had no apparent effect on the Al(im) yield. However, ultra filtration (<10 kDa) caused a significant reduction in the Al(im) concentration using the HQ method. The ultra filtrated Al(im) fraction was similar to the PCV results in the interlaboratory comparison. Retention of colloidal bound Al in the cation exchange column may result in overestimation of Al(im) when the total and HQ methods are used. Estimated Al(im) concentrations derived from two equilibrium models were similar to PCV-derived Al(im) concentrations, as well as the HQ method using ultra filtrated water. The fact that the PCV method does not detect colloidal Al, neither before nor after ion exchange, makes this a preferred technique for Al(im) analysis. Because of the variability in the reported Al(im) concentrations that can arise when different analytical procedures are used, the adoption of a single, reliable technique will facilitate inter-study comparisons and provide consistency in the detection of trends in environmental monitoring programs.

  • 10.
    Borg, Hans
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Andrén,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Sundbom,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Wilander, A.
    Wällstedt,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Episodförsurning - Underlag till Naturvårdsverkets handbok för kalkning av sjöar och vattendrag.2007Report (Other (popular science, discussion, etc.))
  • 11. Cory, N.
    et al.
    Andrén, Cecilia M
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Bishop, K.
    Modelling inorganic Aluminium with WHAM in environmental monitoring2007In: APPLIED GEOCHEMISTRY, ISSN 0883-2927, Vol. 22, p. 1196-1201Article in journal (Refereed)
    Abstract [en]

    Due to the varying toxicity of different Al species, information about Al concentration and speciation is important when assessing water quality. Modelling Al speciation can support operational monitoring programmes where Al speciation is not measured directly. Modelling also makes it possible to retroactively speciate older samples where laboratory fractionation was not undertaken. Organic-rich waters are a particular challenge for both laboratory analysis and models. This paper presents the modelling of Al speciation in Swedish surface waters using the Windermere Humic Acid Model (WHAM). The model was calibrated with data from operational monitoring, the Swedish national survey of lakes and rivers, and covers a broad spectrum of physical and chemical conditions. Calibration was undertaken by varying the amount of DOC active in binding Al. A sensitivity analysis identified the minimum parameters required as model input variables primarily to be total Al, organic C, pH, F-, and secondly Fe, Ca and Mg. The observed and modelled Ali had no significant differences (Spearman rank, p < 0.01), however, lake samples modelled better than rivers. Samples were placed in the correct toxicological category in 89-95% of the cases. The importance of the size of the calibration data set was assessed, and reducing the calibration data set resulted in poorer correlations, but had little impact on the toxicological placement. Overall, the modelling gave satisfactory results from samples covering a broad spectrum of physical and chemical conditions. This indicates the potential value of WHAM as a tool in operational monitoring of surface waters.

  • 12.
    Edberg, F
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Andrén, C
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Förändringar efter avslutad kalkning. Redovisning av delprojekt 3b inom IKEU-utvärderingen 20082008Report (Other academic)
  • 13. Fölster, J.
    et al.
    Andrén, Cecilia
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Bishop, K.
    Buffam, I.
    Cory, N.
    Goedkopp, W.
    Holmgren, K.
    Johnson, R.
    Laudon, H.
    Wilander, A.
    A Novel Environmental Quality Criterion for Acidification in Swedish Lakes – An Application of Studies on the Relationship Between Biota and Water Chemistry2007In: Water Air Soil Pollut: Focus, Vol. 7, p. 331–338-Article in journal (Refereed)
  • 14. Sjöstedt, Carin
    et al.
    Andrén, Cecilia
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Fölster, Jens
    Gustafsson, Jon Petter
    Modelling of pH and inorganic aluminium after termination of liming in 3000 Swedish lakes2013In: Applied Geochemistry, ISSN 0883-2927, E-ISSN 1872-9134, Vol. 35, p. 221-229Article in journal (Refereed)
    Abstract [en]

    Significant resources are spent on counteracting the effects of acidification, mainly by liming. Due to lower S and N deposition in Europe and North America, authorities are changing directives and strategies for remediation and reducing liming. However, as the acid-base buffer capacity differs in different water bodies, the desirable reduction of the lime dose is variable. In this study, a geochemical model is used to predict pH and inorganic monomeric Al (Ali) when liming is reduced and finally terminated in the 3000 Swedish lakes currently treated with lime. To estimate Ca and Mg concentrations not affected by liming for use in the model, the Ca/Mg ratio in nearby unlimed reference lakes was used. For the modelling of pH and inorganic Al the Visual MINTEQ program including the Stockholm Humic Model recently calibrated for Swedish fresh water was used. The predictions were validated with modelling results from six monitored lakes, in which liming had been terminated. The use of geochemical modelling appeared to be a promising tool for the calculation of accurate lime requirements in acid waters. For simulations in which liming was completely terminated, the pH value decreased by, on average, 1 pH unit to pH 5.7, whereas Ali increased by 17 mu g L (1) to 32 mu g L (1). If liming was reduced by half, the pH would drop only 0.3 pH units and Ali would increase by 2 mu g L (1). Lakes in the south-western part of Sweden were predicted to reach a lower pH and higher Ali, which would be expected due to their greater historical S deposition. The results indicate that liming can be terminated in certain areas and in other areas be reduced without increases in the lake acidity.

  • 15.
    Sundbom,
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Andrén,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Borg, Hans
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Edberg, Frida
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Persson, G.
    Wällstedt,
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Kalkningsavslut - Underlag till Naturvårdsverkets handbok för kalkning av sjöar och vattendrag.2007Report (Other (popular science, discussion, etc.))
  • 16.
    Teien, Hans-Christian
    et al.
    Agricultural University of Norway, Department of Plant and Environmental Sciences, Aas, Norway.
    Andrén, Cecilia M.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Kroglund, Frode
    Norwegian Institute for Water Research (NIVA), Grimstad , Norway.
    Salbu, Brit
    Agricultural University of Norway, Department of Plant and Environmental Sciences, Aas, Norway.
    Changes in gill reactivity of aluminium species following liming of an acid and aluminium-rich humic water2005In: Verhandlungen / Internationale Vereinigung für Theoretische und Angewandte Limnologie, ISSN 0368-0770, Vol. 29, p. 837-840Article in journal (Refereed)
  • 17. Wilander, A.
    et al.
    Andrén, C
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Bergquist, B.
    Holmgren, K.
    Persson, G.
    Sundbom, M
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Urval och representativitet – Redovisning av delprojekt 1b inom IKEU-utvärderingen 20082008Report (Other academic)
  • 18. Wilander, A.
    et al.
    Andrén, C
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Bergquist, B.
    Holmgren, K.
    Sundbom, M
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Provtagning och analysanarbete – Redovisning av delprojekt 1a inom IKEU-utvärderingen 20082008Report (Other academic)
1 - 18 of 18
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