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  • 1301.
    Toreti, Andrea
    et al.
    Joint Research Centre (JRC), European Commission, Ispra (VA), Italy.
    Belward, Alan
    Joint Research Centre (JRC), European Commission, Ispra (VA), Italy.
    Perez-Dominguez, Ignacio
    European Commission, Joint Research Centre (JRC), Seville, Spain.
    Naumann, Gustavo
    Joint Research Centre (JRC), European Commission, Ispra (VA), Italy.
    Luterbacher, Jürg
    Dept. of Geography, Climatology, Climate Dynamics and Climate Change, and Centre for International Development and Environmental Research, Justus-Liebig University of Giessen, Germany.
    Cronie, Ottmar
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för matematik och matematisk statistik.
    Seguini, Lorenzo
    Joint Research Centre (JRC), European Commission, Ispra (VA), Italy.
    Manfron, Giacinto
    Joint Research Centre (JRC), European Commission, Ispra (VA), Italy.
    Lopez Lozano, Raul
    Joint Research Centre (JRC), European Commission, Ispra (VA), Italy.
    Baruth, Bettina
    Joint Research Centre (JRC), European Commission, Ispra (VA), Italy.
    van den Berg, Maurits
    Joint Research Centre (JRC), European Commission, Ispra (VA), Italy.
    Dentener, Frank
    Joint Research Centre (JRC), European Commission, Ispra (VA), Italy.
    Ceglar, Andrej
    Joint Research Centre (JRC), European Commission, Ispra (VA), Italy.
    Chatzopoulos, Thomas
    Joint Research Centre (JRC), European Commission, Seville, Spain.
    Zampieri, Matteo
    Joint Research Centre, European Commission, Ispra (VA), Italy.
    The exceptional 2018 European water seesaw calls for action on adaptation2019Inngår i: Earth's Future, ISSN 1384-5160, E-ISSN 2328-4277, Vol. 7, nr 6, s. 652-663Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Temperature and precipitation are the most important factors responsible for agricultural productivity variations. In 2018 spring/summer growing season, Europe experienced concurrent anomalies of both. Drought conditions in central and northern Europe caused yield reductions up to 50% for the main crops, yet wet conditions in southern Europe saw yield gains up to 34%, both with respect to the previous 5‐years' mean. Based on the analysis of documentary and natural proxy based seasonal paleoclimate reconstructions for the past half millennium, we show that the 2018 combination of climatic anomalies in Europe was unique. The water seesaw, a marked dipole of negative water anomalies in central Europe and positive ones in southern Europe, distinguished 2018 from the five previous similar droughts since 1976. Model simulations reproduce the 2018 European water seesaw in only four years out of 875 years in historical runs and projections. Future projections under the RCP8.5 scenario show that 2018‐like temperature and rainfall conditions, favourable to crop growth, will occur less frequent in southern Europe. In contrast, in central Europe high‐end emission scenario climate projections show that droughts as intense as 2018 could become a common occurrence as early as 2043. Whilst integrated European and global agricultural markets limited agro‐economic shocks caused by 2018's extremes, there is an urgent need for adaptation strategies for European agriculture to consider futures without the benefits of any water seesaw.

  • 1302.
    Toreti, Andrea
    et al.
    European Commission, Ispra (VA), Italy.
    Cronie, Ottmar
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för matematik och matematisk statistik.
    Zampieri, Matteo
    European Commission, Ispra (VA), Italy.
    Concurrent climate extremes in the key wheat producing regions of the world2019Inngår i: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 9, artikkel-id 5493Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Climate extremes have profound impacts on key socio-economic sectors such as agriculture. In a changing climate context, characterised by an intensification of these extremes and where the population is expected to grow, exposure and vulnerability must be accurately assessed. However, most risk assessments analyse extremes independently, thus potentially being overconfident in the resilience of the socio-economic sectors. Here, we propose a novel approach to defining and characterising concurrent climate extremes (i.e. extremes occurring within a specific temporal lag), which is able toidentify spatio-temporal dependences without making any strict assumptions. the method is applied to large-scale heat stress and drought events in the key wheat producing regions of the world, as these extremes can cause serious yield losses and thus trigger market shocks. Wheat regions likely to haveconcurrent extremes (heat stress and drought events) are identified, as well as regions independent ofeach other or inhibiting each other in terms of these extreme events. this tool may be integrated in all risk assessments but could also be used to explore global climate teleconnections.

  • 1303.
    Torstensson, Linn
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Giftfri förskola: Hur upplever förskolorna kommunernas hjälp?2017Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The purpose of this study is to evaluate how, and if, Sweden's municipalities contribute to their preschools work for a toxic free environment, and what the schools think of the support they are receiving. The study will also focus on the municipality of Uddevalla and evaluate status and progress of making a chemical-safe environment for preschool children. The study was performed by sending out two different surveys by email to preschool principals and municipalities. The results of the study showed that Sweden's municipalities mostly support the preschools by offering information, education, action plans and procurement. A majority of the preschool principals answered that the support they receive was partially the reason for why they are able to work with such a project. They also think in most cases that the support is sufficient to carry out the work. The support of the municipality in the work is for some preschools crucial. The result of the study of Uddevalla shows that in 72 % of the preschools have or are working with a project to eliminate children's exposure to toxic chemicals. The remaining 28 % are not working with such a project and have no plan to do so. The results based on the survey in Uddevalla is in good agreement with the rest of Sweden, where 86 % of the principals answered that they have or are working with such a project. These results show that Swedish preschools are heading for a more chemical safe environment, although a lot needs to be done before it is accomplished. 

  • 1304.
    Törnlund, Erik
    Umeå universitet, Samhällsvetenskapliga fakulteten, Demografiska databasen.
    From Natural to Modified Rivers and Back?: Timber Floating in Northern Sweden in 1850-1980 and the Use of Historical Knowledge in Today's Ecological Stream Restoration2011Inngår i: Thinking through the environment: Green approaches to global history / [ed] Timo Myllyntaus, Knapwell, Cambridge: White Horse Press, 2011, s. 243-267Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 1305. Uboni, Alessia
    et al.
    Smith, Douglas W
    Mao, Julie S
    Stahler, Daniel R
    Vucetich, John A
    Long- and short-term temporal variability in habitat selection of a top predator2015Inngår i: Ecosphere, ISSN 2150-8925, E-ISSN 2150-8925, Vol. 6, nr 4, artikkel-id 51Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Considerable theory explains the importance of understanding temporal variation in ecological processes. Nevertheless, long-term variability in habitat selection is rarely assessed or even acknowledged. We explored temporal variability in the habitat selection of a top-predator, the wolf (Canis lupus), at two time scales: interannual and seasonal variability. To do this, we developed resource utilization functions to relate wolf habitat selection to environmental variables in different years and seasons. We used radiotelemetry data collected from a wolf population in Yellowstone National Park during a 10-year period (1998-2007) and added a Year variable in the models to account for interannual variation in the studied processes. We also used a three-year data set (nested within the 10-year data set) to incorporate additional variables in the models and test for differences in short- and long-term patterns of habitat selection. Wolves exhibited seasonal variation in habitat selection with respect to distance from roads, elevation, openness, and habitat type. Habitat selection was considerably more complicated during the winter compared to summer, when wolves only selected habitat based on distance from roads. We detected clear patterns of habitat selection in the three-year data set that could not be detected in the 10-year data set, despite the longer data set had more statistical power for pattern detection. This observation is likely the result of the longer data set being comprised of several shorter-term and countervailing patterns. This explanation is also consistent with having detected significant year effects in the 10-year data set. Insomuch as habitat selection is important to conservation and management, this research is significant for demonstrating the different impressions that can be given by short-term and long-term studies. It may be common for short-term data sets to suggest patterns of habitat selection that do not prevail over longer periods of time.

  • 1306.
    Uboni, Alessia
    et al.
    School of Forest Resources and Environmental Science, Michigan Technological University, Houghton, Michigan, USA.
    Vucetich, John A.
    Stahler, Daniel R.
    Smith, Douglas W.
    Interannual variability: a crucial component of space use at the territory level2015Inngår i: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 96, nr 1, s. 62-70Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Interannual variability in space use and how that variation is influenced by density-dependent and density-independent factors are important processes in population ecology. Nevertheless, interannual variability has been neglected by the majority of space use studies. We assessed that variation for wolves living in 15 different packs within Yellowstone National Park during a 13-year period (1996–2008). We estimated utilization distributions to quantify the intensity of space use within each pack's territory each year in summer and winter. Then, we used the volume of intersection index (VI) to quantify the extent to which space use varied from year to year. This index accounts for both the area of overlap and differences in the intensity of use throughout a territory and ranges between 0 and 1. The mean VI index was 0.49, and varied considerably, with ~20% of observations (n = 230) being <0.3 or >0.7. In summer, 42% of the variation was attributable to differences between packs. These differences can be attributable to learned behaviors and had never been thought to have such an influence on space use. In winter, 34% of the variation in overlap between years was attributable to interannual differences in precipitation and pack size. This result reveals the strong influence of climate on predator space use and underlies the importance of understanding how climatic factors are going to affect predator populations in the occurrence of climate change. We did not find any significant association between overlap and variables representing density-dependent processes (elk and wolf densities) or intraspecific competition (ratio of wolves to elk). This last result poses a challenge to the classic view of predator–prey systems. On a small spatial scale, predator space use may be driven by factors other than prey distribution.

  • 1307. Ujvari, Beata
    et al.
    Andersson, Stefan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Brown, Gregory
    Shine, Richard
    Madsen, Thomas
    Climate-driven impacts of prey abundance on the population structure of a tropical aquatic predator2010Inngår i: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 119, nr 1, s. 188-196Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In the present study we explore how annual variation in climate (late wet-season rainfall) affects population demography in a gape-limited obligate piscivorous predator, the Arafura filesnake Acrochordus arafurae in the Australian tropics. These aquatic snakes display extreme sexual dimorphism, with body sizes and relative head sizes of females much larger than those of males. Two consecutive years with low rainfall during the late wet season reduced the abundance of small but not large sized fish. Although snake residual body mass (RBM, calculated from a general linear regression of ln-transformed mass to ln-SVL) decreased after the first year with low prey availability, it was not until the second year that reduced prey abundance caused a dramatic decline in filesnake survival, and hence in population numbers. Thus, our results suggest that most snakes survived the first year of reduced prey abundance, but a successive year with low prey availability proved fatal for many animals. However, the effects of prey scarcity on RBM and survival fell disproportionately on some size classes of snakes. Medium-sized animals (large males and intermediate-sized females) were affected more dramatically than were small or large snakes. We attribute the higher survival of small snakes to their lower energy needs compared to medium-sized individuals, and the higher survival of large snakes to the continued abundance of large prey (mainly large catfish). Two successive years with low abundance of smaller sized prey thus massively modified the size-structure of the filesnake population, virtually eliminating large males and intermediate-sized females. Our field data provide a clear demonstration of the ways in which stochastic variation in climatic conditions can have dramatic effects on predator population demography, mediated via effects on prey availability.

  • 1308. Ushio, Masayuki
    et al.
    Makoto, Kobayashi
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Klaminder, Jonatan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Takasu, Hiroyuki
    Nakano, Shin-ichi
    High-throughput sequencing shows inconsistent results with a microscope-based analysis of the soil prokaryotic community2014Inngår i: Soil Biology and Biochemistry, ISSN 0038-0717, E-ISSN 1879-3428, Vol. 76, s. 53-56Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In the present study, we perform the first direct analysis on how the composition of the prokaryotic soil community differs depending on whether high-throughput sequencing or fluorescent in situ hybridization (FISH) coupled with catalyzed reporter deposition (CARD) is used. Soil samples were collected along short (<3 m) tundra vegetation gradients from Northern Sweden. Relative abundances of Acid-obacteria and Bacteroidetes estimated by the high-throughput sequencing were higher than those estimated by CARD-FISH, while relative abundances of Archaea and alpha-Proteobacteria estimated by high-throughput sequencing were lower than those estimated by CARD-FISH. The results indicated that the high-throughput sequencing overestimates/underestimates the relative abundance of some microbial taxa if we assume that CARD-FISH can provide potentially more quantitative data. Great caution should be taken when interpreting data generated by molecular technologies (both of high-throughput sequencing and CARD-FISH), and supports by multiple approaches are necessary to make a robust conclusion. (C) 2014 Elsevier Ltd. All rights reserved.

  • 1309. Vaisanen, Maria
    et al.
    Ylanne, Henni
    Kaarlejärvi, Elina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Sjoegersten, Sofie
    Olofsson, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Crout, Neil
    Stark, Sari
    Consequences of warming on tundra carbon balance determined by reindeer grazing history2014Inngår i: Nature Climate Change, ISSN 1758-678X, E-ISSN 1758-6798, Vol. 4, nr 5, s. 384-388Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Arctic tundra currently stores half of the global soil carbon (C) stock(1). Climate warming in the Arctic may lead to accelerated CO2 release through enhanced decomposition and turn Arctic ecosystems from a net C sink into a net C source, if warming enhances decomposition more than plant photosynthesis(2). A large portion of the circumpolar Arctic is grazed by reindeer/caribou, and grazing causes important vegetation shifts in the long-term. Using a unique experimental set-up, where areas experiencing more than 50 years of either light (LG) or heavy (HG) grazing were warmed and/or fertilized, we show that under ambient conditions areas under LG were a 70% stronger C sink than HG areas. Although warming decreased the C sink by 38% under LG, it had no effect under HG. Grazing history will thus be an important determinant in the response of ecosystem C balance to climate warming, which at present is not taken into account in climate change models.

  • 1310. Valerio, Aline de Matos
    et al.
    Kampel, Milton
    Vantrepotte, Vincent
    Ward, Nicholas D.
    Sawakuchi, Henrique Oliveira
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Universidade de São Paulo, USP/CENA, Piracicaba, SP, Brazil .
    Da Silva Less, Diani Fernanda
    Neu, Vania
    Cunha, Alan
    Richey, Jeffrey
    Using CDOM optical properties for estimating DOC concentrations and pCO2 in the Lower Amazon River2018Inngår i: Optics Express, ISSN 1094-4087, E-ISSN 1094-4087, Vol. 26, nr 14, s. A657-A677Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Coloured dissolved organic matter (CDOM) is one of the major contributors to the absorption budget of most freshwaters and can be used as a proxy to assess non-optical carbon fractions such as dissolved organic carbon (DOC) and the partial pressure of carbon dioxide (pCO2). Nevertheless, riverine studies that explore the former relationships are still relatively scarce, especially within tropical regions. Here we document the spatial-seasonal variability of CDOM, DOC and pCO2, and assess the potential of CDOM absorption coefficient (aCDOM(412)) for estimating DOC concentration and pCO2 along the Lower Amazon River. Our results revealed differences in the dissolved organic matter (DOM) quality between clearwater (CW) tributaries and the Amazon River mainstream. A linear relationship between DOC and CDOM was observed when tributaries and mainstream are evaluated separately (Amazon River: N = 42, R2 = 0.74, p<0.05; CW: N = 13, R2 = 0.57, p<0.05). However, this linear relationship was not observed during periods of higher rainfall and river discharge, requiring a specific model for these time periods to be developed (N = 25, R2 = 0.58, p<0.05). A strong linear positive relation was found between aCDOM(412) and pCO2(N = 69, R2 = 0.65, p<0.05) along the lower river. pCO2 was less affected by the optical difference between tributaries and mainstream waters or by the discharge conditions when compared to CDOM to DOC relationships. Including the river water temperature in the model improves our ability to estimate pCO(2) (N = 69; R2 = 0.80, p<0.05). The ability to assess both DOC and pCO2 from CDOM optical properties opens further perspectives on the use of ocean colour remote sensing data for monitoring carbon dynamics in large running water systems worldwide.

  • 1311.
    Valinia, Salar
    et al.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Englund, Göran
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Moldan, Filip
    IVL Swedish Environmental Research Institute, Göteborg, Sweden.
    Futter, Martyn N.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Kohler, Stephan J.
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Bishop, Kevin
    Department of Earth Sciences, Uppsala University, Uppsala, Sweden and Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Folster, Jens
    Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Assessing anthropogenic impact on boreal lakes with historical fish species distribution data and hydrogeochemical modeling2014Inngår i: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 20, nr 9, s. 2752-2764Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Quantifying the effects of human activity on the natural environment is dependent on credible estimates of reference conditions to define the state of the environment before the onset of adverse human impacts. In Europe, emission controls that aimed at restoring ecological status were based on hindcasts from process-based models or paleolimnological reconstructions. For instance, 1860 is used in Europe as the target for restoration from acidification concerning biological and chemical parameters. A more practical problem is that the historical states of ecosystems and their function cannot be observed directly. Therefore, we (i) compare estimates of acidification based on long-term observations of roach (Rutilus rutilus) populations with hindcast pH from the hydrogeochemical model MAGIC; (ii) discuss policy implications and possible scope for use of long-term archival data for assessing human impacts on the natural environment and (iii) present a novel conceptual model for interpreting the importance of physico-chemical and ecological deviations from reference conditions. Of the 85 lakes studied, 78 were coherently classified by both methods. In 1980, 28 lakes were classified as acidified with the MAGIC model, however, roach was present in 14 of these. In 2010, MAGIC predicted chemical recovery in 50% of the lakes, however roach only recolonized in five lakes after 1990, showing a lag between chemical and biological recovery. Our study is the first study of its kind to use long-term archival biological data in concert with hydrogeochemical modeling for regional assessments of anthropogenic acidification. Based on our results, we show how the conceptual model can be used to understand and prioritize management of physico-chemical and ecological effects of anthropogenic stressors on surface water quality.

  • 1312. Valinia, Salar
    et al.
    Futter, Martyn N.
    Cosby, Bernard J.
    Rosen, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Folster, Jens
    Simple Models to Estimate Historical and Recent Changes of Total Organic Carbon Concentrations in Lakes2015Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 49, nr 1, s. 386-394Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Quantifying human impacts on the natural environment requires credible reconstructions of reference conditions. Anthropogenic acidification of surface waters is strongly influenced by total organic carbon (TOC) concentrations. Because both the degree of acidification and recovery are dependent on historical TOC concentrations, simple models to estimate changes in surface water TOC between reference conditions (1860) and the present day (2012) are needed. We used visible near infrared spectroscopy (VNIRS) of lake sediments to reconstruct reference condition TOC and long-term monitoring data to predict recent changes. Two empirical models were developed to predict: (i) historical TOC trends between reference conditions (1860) and peak acidification (1980) and (ii) trends in TOC between 1988 and 2012. The models were statistically robust with adj. R(2) of (i) 0.85 and (ii) 0.71, respectively. Models were driven by lake and catchment area, wetlands, historical sulfur deposition and water chemistry. Present day TOC concentrations are similar to VNIRS-reconstructed and modeled reference condition TOC in Swedish lakes. The results are valuable for understanding drivers of TOC changes in lakes and for more credible assessments of reference conditions needed for water management in Europe and elsewhere.

  • 1313.
    Vallin, Sara
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    LiDAR-bildanalys av flutings i södra Norrbotten: Kartering och datering av avvikande isrörelseriktningar2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The aim of this study was to map and date glacial flutings with ice flows deviating from the predominating northwesterly ice flow direction in the southern part of Norrbotten County in northern Sweden, and also to investigate if parts of the glacial landscape are older than previously thought. The traditional view is that most landforms in the area were formed during the late Weichselian (W3). Analysis of the new high resolution elevation model (2 m grid) derived from laser scanning was performed after treating the data with a hillshade tool in ArcMap to reveal terrain features such as flutings. The analysis resulted in a map showing four main groups of deviating ice flows (N-S, NO-SV, SO-NV and S-N) and several westerly ice flows. The majority of flutings with deviating ice flows were found in low terrain. This, together with studies suggesting a cold based late Weichselian ice sheet in Norrbotten, implies an old age of the deviating ice flows. The deviating ice flows are interpreted to originate from the first early Weichselian (W1), or predate the onset of the Weichselian glaciation. Some NV-SO flutings were located in high terrain, which implies a younger age relative to the low terrain flutings. They represent the youngest ice flow found in the area, possibly from the second early Weichselian (W2). The new elevation model clearly offers new possibilities for studying small scale landforms and shows that the traditional view of the Weichselian glaciation in northern Swedish needs to be reconsidered.

  • 1314. van den Berg, Martin
    et al.
    Denison, Michael S
    Birnbaum, Linda S
    DeVito, Michael J
    Fiedler, Heidelore
    Falandysz, Jerxy
    Rose, Martin
    Schrenk, Dieter
    Safe, Stephen
    Tohyama, Chiharu
    Tritscher, Angelika
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Peterson, Richard E
    Polybrominated Dibenzo-p-Dioxins, Dibenzofurans, and Biphenyls: Inclusion in the Toxicity Equivalency Factor Concept for Dioxin-Like Compounds2013Inngår i: Toxicological Sciences, ISSN 1096-6080, E-ISSN 1096-0929, Vol. 133, nr 2, s. 197-208Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    In 2011 a joint World Health Organization (WHO) and United Nations Environment Programme (UNEP) expert consultation took place, during which the possible inclusion of brominated analogues of the dioxin-like compounds in the WHO Toxicity Equivalency Factor (TEF) scheme were evaluated. The expert panel concluded that polybrominated dibenzo-p-dioxins (PBDDs), dibenzofurans (PBDFs), and some dioxin-like biphenyls (dl-PBBs) may contribute significantly in daily human background exposure to the total dioxin toxic equivalencies (TEQs). These compounds are also commonly found in the aquatic environment. Available data for fish toxicity were evaluated for possible inclusion in the WHO-UNEP TEF scheme (Van den Berg et al., 1998). Because of the limited database it was decided not to derive specific WHO-UNEP TEFs for fish, but for ecotoxicological risk assessment the use of specific relative effect potencies (REPs) from fish embryo assays is recommended. Based on the limited mammalian REP database for these brominated compounds, it was concluded that sufficient differentiation from the present TEF values of the chlorinated analogues (Van den Berg et al., 2005) was not possible. However, the REPs for PBDDs, PBDFs, and non-ortho dl-PBBs in mammals closely follow those of the chlorinated analogues, at least within one order of magnitude. Therefore, the use of similar interim TEF values for brominated and chlorinated congeners for human risk assessment is recommended, pending more detailed information in the future.

  • 1315. Van den Brink, Paul J.
    et al.
    Boxall, Alistair B. A.
    Maltby, Lorraine
    Brooks, Bryan W.
    Rudd, Murray A.
    Backhaus, Thomas
    Spurgeon, David
    Verougstraete, Violaine
    Ajao, Charmaine
    Ankley, Gerald T.
    Apitz, Sabine E.
    Arnold, Kathryn
    Brodin, Tomas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Cañedo-Argüelles, Miguel
    Chapman, Jennifer
    Corrales, Jone
    Coutellec, Marie-Agnès
    Fernandes, Teresa F.
    Fick, Jerker
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Ford, Alex T.
    Giménez Papiol, Gemma
    Groh, Ksenia J.
    Hutchinson, Thomas H.
    Kruger, Hank
    Kukkonen, Jussi V. K.
    Loutseti, Stefania
    Marshall, Stuart
    Muir, Derek
    Ortiz-Santaliestra, Manuel E.
    Paul, Kai B.
    Rico, Andreu
    Rodea-Palomares, Ismael
    Römbke, Jörg
    Rydberg, Tomas
    Segner, Helmut
    Smit, Mathijs
    van Gestel, Cornelis A. M.
    Vighi, Marco
    Werner, Inge
    Zimmer, Elke I.
    van Wensem, Joke
    Toward sustainable environmental quality: Priority research questions for Europe2018Inngår i: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 37, nr 9, s. 2281-2295Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The United Nations' Sustainable Development Goals have been established to end poverty, protect the planet, and ensure prosperity for all. Delivery of the Sustainable Development Goals will require a healthy and productive environment. An understanding of the impacts of chemicals which can negatively impact environmental health is therefore essential to the delivery of the Sustainable Development Goals. However, current research on and regulation of chemicals in the environment tend to take a simplistic view and do not account for the complexity of the real world, which inhibits the way we manage chemicals. There is therefore an urgent need for a step change in the way we study and communicate the impacts and control of chemicals in the natural environment. To do this requires the major research questions to be identified so that resources are focused on questions that really matter. We present the findings of a horizon-scanning exercise to identify research priorities of the European environmental science community around chemicals in the environment. Using the key questions approach, we identified 22 questions of priority. These questions covered overarching questions about which chemicals we should be most concerned about and where, impacts of global megatrends, protection goals, and sustainability of chemicals; the development and parameterization of assessment and management frameworks; and mechanisms to maximize the impact of the research. The research questions identified provide a first-step in the path forward for the research, regulatory, and business communities to better assess and manage chemicals in the natural environment. 

  • 1316.
    van Ede, Karin I.
    et al.
    Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands.
    Andersson, Patrik L.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Gaisch, Konrad P. J.
    Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands.
    van den Berg, Martin
    Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands.
    van Duursen, Majorie B. M.
    Institute for Risk Assessment Sciences, Utrecht University, Utrecht, the Netherlands.
    Comparison of Intake and Systemic Relative Effect Potencies of Dioxin-like Compounds in Female Mice after a Single Oral Dose2013Inngår i: Journal of Environmental Health Perspectives, ISSN 0091-6765, E-ISSN 1552-9924, Vol. 121, nr 7, s. 847-853Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    BACKGROUND: Risk assessment for mixtures of polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs), and polychlorinated biphenyls (PCBs) is performed using the toxic equivalency factor (TEF) approach. These TEF values are derived mainly from relative effect potencies (REPs) linking an administered dose to an in vivo toxic or biological effect, resulting in "intake" TEFs. At present, there is insufficient data available to conclude that intake TEFs are also applicable for systemic concentrations (e. g., blood and tissues). OBJECTIVE: We compared intake and systemic REPs of 1,2,3,7,8-pentachlorodibenzodioxin (PeCDD), 2,3,4,7,8-pentachlorodibenzofuran (4-PeCDF), 3,3', 4,4', 5-pentachlorobiphenyl (PCB-126), 2,3', 4,4', 5-pentachlorobiphenyl (PCB-118), and 2,3,3', 4,4', 5-hexachlorobiphenyl (PCB-156) in female C57BL/6 mice 3 days after a single oral dose. METHODS: We calculated intake REPs and systemic REPs based on administered dose and liver, adipose, or plasma concentrations relative to TCDD. Hepatic cytochrome P450 1Al-associated ethoxyresorufin-O-deethylase (EROD) activity and gene expression of Cyp1a1, 1a2 and 1b1 in the liver and peripheral blood lymphocytes (PBLs) were used as biological end points. RESULTS: We observed up to one order of magnitude difference between intake REPs and systemic REPs. Two different patterns were discerned. Compared with intake REPs, systemic REPs based on plasma or adipose levels were higher for PeCDD, 4-PeCDF, and PCB-126 but lower for the mono-ortho PCBs 118 and 156. CONCLUSIONS: Based on these mouse data, the comparison between intake REPs and systemic REPs reveals significant congener-specific differences that warrants the development of systemic TEFs to calculate toxic equivalents (TEQs) in blood and body tissues.

  • 1317. Van, Khuong Dinh
    et al.
    Janssens, Lizanne
    Debecker, Sara
    De Jonge, Maarten
    Lambret, Philippe
    Nilsson-Örtman, Viktor
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Bervoets, Lieven
    Stoks, Robby
    Susceptibility to a metal under global warming is shaped by thermal adaptation along a latitudinal gradient2013Inngår i: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 19, nr 9, s. 2625-2633Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Global warming and contamination represent two major threats to biodiversity that have the potential to interact synergistically. There is the potential for gradual local thermal adaptation and dispersal to higher latitudes to mitigate the susceptibility of organisms to contaminants and global warming at high latitudes. Here, we applied a space-for-time substitution approach to study the thermal dependence of the susceptibility of Ischnura elegans damselfly larvae to zinc in a common garden warming experiment (20 and 24 degrees C) with replicated populations from three latitudes spanning >1500 km in Europe. We observed a striking latitude-specific effect of temperature on the zinc-induced mortality pattern; local thermal adaptation along the latitudinal gradient made Swedish, but not French, damselfly larvae more susceptible to zinc at 24 degrees C. Latitude-and temperature-specific differences in zinc susceptibility may be related to the amount of energy available to defend against and repair damage since Swedish larvae showed a much stronger zinc-induced reduction of food intake at 24 degrees C. The pattern of local thermal adaptation indicates that the predicted temperature increase of 4 degrees C by 2100 will strongly magnify the impact of a contaminant such as zinc at higher latitudes unless there is thermal evolution and/or migration of lower latitude genotypes. Our results underscore the critical importance of studying the susceptibility to contaminants under realistic warming scenarios taking into account local thermal adaptation across natural temperature gradients.

  • 1318. van Leeuwen, Anieke
    et al.
    Huss, Magnus
    Gardmark, Anna
    Casini, Michele
    Vitale, Francesca
    Hjelm, Joakim
    Persson, Lennart
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    de Roos, Andre M
    Predators with multiple ontogenetic niche shifts have limited potential for population growth and top-down control of their prey2013Inngår i: American Naturalist, ISSN 0003-0147, E-ISSN 1537-5323, Vol. 182, nr 1, s. 53-66Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Catastrophic collapses of top predators have revealed trophic cascades and community structuring by top-down control. When populations fail to recover after a collapse, this may indicate alternative stable states in the system. Overfishing has caused several of the most compelling cases of these dynamics, and in particular Atlantic cod stocks exemplify such lack of recovery. Often, competition between prey species and juvenile predators is hypothesized to explain the lack of recovery of predator populations. The predator is then considered to compete with its prey for one resource when small and to subsequently shift to piscivory. Yet predator life history is often more complex than that, including multiple ontogenetic diet shifts. Here we show that no alternative stable states occur when predators in an intermediate life stage feed on an additional resource (exclusive to the predator) before switching to piscivory, because predation and competition between prey and predator do not simultaneously structure community dynamics. We find top-down control by the predator only when there is no feedback from predator foraging on the additional resource. Otherwise, the predator population dynamics are governed by a bottleneck in individual growth occurring in the intermediate life stage. Therefore, additional resources for predators may be beneficial or detrimental for predator population growth and strongly influence the potential for top-down community control.

  • 1319. Van Oostdam, Jay C
    et al.
    Dewailly, E
    Gilman, A
    Hansen, J C
    Odland, J O
    Chashchin, V
    Berner, J
    Butler-Walker, J
    Lagerkvist, Birgitta Json
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin.
    Olafsdottir, K
    Soininen, L
    Bjerregard, P
    Klopov, V
    Weber, J P
    Circumpolar maternal blood contaminant survey, 1994-1997 organochlorine compounds2004Inngår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 330, nr 1-3, s. 55-70Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    During the past 20 years a number of studies have found neurological and immunological effects in the developing fetus and infants exposed to background or only slightly elevated levels of persistent organic pollutants (POPs) such as polychlorinated biphenyls (PCBs). To address concerns arising from possible increased human exposure in the Arctic and possible effects of POPs, all circumpolar countries agreed in 1994 to monitoring of specific human tissues for contaminants in the Arctic under the Arctic Monitoring and Assessment Program (AMAP). Mothers in eight circumpolar countries contributed blood samples that were analysed at a single laboratory for 14 PCB congeners (IUPAC No. 28, 52, 99, 105, 118, 128, 138, 153, 156, 170, 180, 183, 187) and 13 organochlorine pesticides (aldrin, beta-hexachlorocyclohexane (beta-HCH), dichlordiphenyltrichloroethane (p,p'-DDT), diphenyldichloroethylene (p,p'DDE), dieldrin, heptachlorepoxide, hexachlorobenzene (HCB), mirex, and the chlordane derivatives alpha-chlordane, gamma-chlordane, cis-nonachlor, oxychlordane and trans-nonachlor). Inuit mothers from Greenland and Canada have significantly higher levels of oxychlordane, transnonachlor and mirex than mothers from Norway, Sweden, Iceland and Russia. Inuit mothers from Greenland also have significantly higher levels of these contaminants than Inuit mothers from Canada and Alaska. These differences among Inuit groups may represent regional dietary preferences or different contaminant deposition patterns across the Arctic. Levels of PCBs are also elevated among some arctic populations due to their consumption of marine mammals and are in the range where subtle effects on leaming and the immune system have been reported. The Russian mothers who consume mainly food imported from southern Russia have elevated levels of DDT, DDE, beta-HCH and a higher proportion of lower chlorinated PCB congeners. This study has allowed an assessment of the variation of contaminants such as PCBs and various organochlorine pesticides (DDT, chlordane, etc.) in human populations around the circumpolar north.

  • 1320.
    van Woerkom, Anne
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Ancient DNA from soils and sediments from the Krigstjärn area, northern Sweden: Preservation and detection of Holocene mammal sedaDNA2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Current knowledge of past vegetation and faunal diversity has been based on pollen and macrofossil analysis from lake sediments. The innovative method of sedimentary ancient DNA (sedaDNA) is a promising, complementary proxy to reconstruct information about past environments. However, to what extent animal DNA can be extracted from old sediments and soils has not been frequently studied. This study explored if ancient DNA of moose (Alces alces), reindeer (Rangifer tarangus), goat (Capra aegagrus) and plants could be extracted from millennia old lake sediments of Lake Krigstjärn and archaeological soil samples in northern Sweden. SedaDNA was successfully extracted and detected from both reindeer and plants DNA, while goats sedaDNA was absent in all sediments. Moose ancient DNA (aDNA) was only detected in the archaeological soils. Yet, there were signs that the applied moose primer set was not optimal for heavily degraded DNA and the validity of this primer needs further research. Earliest detections of reindeer DNA can be dated to ~6500 c. years ago. Oldest sediments contained DNA, indicating sufficient DNA preservation conditions in the sediments of Lake Krigstjärn. Finds of plants DNA in pre-deglaciational sediments may indicate the existence of >9500 year old glacial vegetation. Altogether is sedaDNA a highly promising tool to reconstruct diversity, origin and immigration routes of mammals, but technical issues such as primer set specificity and its purpose should be considered and tested carefully in advance. 

  • 1321.
    van Woerkom, Anne
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Cryptic refugia vs. Tabula Rasa: Boreal trees in glacial Fennoscandia: Plant growth during the Weichselian glaciation and the early Holocene in northern Europe2016Independent thesis Advanced level (degree of Master (Two Years)), 10 poäng / 15 hpOppgave
    Abstract [en]

    Recent studies applying innovative technologies, such as genetic analysis and carbon dating, contradict the palynological based assumption that Scots pine (Pinus sylvestris) and Norway spruce (Picea abies) vanished from Fennoscandia during the Last Glacial Maximum (c. 20.000 yrs BP) and re-colonized after the cold Younger Dryas (c. 12.000 yrs BP). Instead, those studies indicate glacial survival of boreal trees in ‘cryptic’ refugia within Scandinavia, which is still heavily debated. In this report, I try to get a better grip on the discussion if Norway spruce and Scots pine survived Weichselian glacial periods in isolated ‘cryptic’ refugia within Scandinavia, or either re-colonized Fennoscandia by post-glacial migration from eastern areas such as Russia. To this aim, climatic settings are described and an overview is given on what is already known on the distribution of boreal trees during the Weichselian glaciations and the post-glacial landscape. Several records are important to detect ancient boreal trees: pollen, macrofossils and currently DNA. Macrofossils indicate early post-glacial tree growth in the central Scandes just after the Younger Dryas, aDNA indicates the existence of a ‘cryptic’ refugium on Andøya during the Last Glacial Maximum and modern DNA analysis possibly indicates isolation of spruce in western Norway, which are all contradicted by the current interpretation of low pollen percentages. Altogether, alternative hypotheses supporting glacial survival of plants might have been overlooked and pollen interpretations need revision, which could turn the exclusion from the past into supporting evidence for the glacial survival of P. abies and P. sylvestris in Scandinavia.

  • 1322.
    Vaquer-Sunyer, Raquel
    et al.
    Lund Univ.
    Conley, Daniel J.
    Lund Univ.
    Muthusamy, Sarala Devi
    Linnéuniversitetet, Institutionen för biologi och miljö (BOM).
    Lindh, Markus V.
    Linnéuniversitetet, Institutionen för biologi och miljö (BOM).
    Pinhassi, Jarone
    Linnéuniversitetet, Institutionen för biologi och miljö (BOM).
    Kritzberg, Emma S.
    Lund Univ.
    Dissolved Organic Nitrogen Inputs from Wastewater Treatment Plant Effluents Increase Responses of Planktonic Metabolic Rates to Warming2015Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 49, nr 19, s. 11411-11420Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Increased anthropogenic pressures on coastal marine ecosystems in the last century are threatening their biodiversity and functioning. Global warming and increases in nutrient loadings are two major stressors affecting these systems. Global warming is expected to increase both atmospheric and water temperatures and increase precipitation and terrestrial runoff, further increasing organic matter and nutrient inputs to coastal areas. Dissolved organic nitrogen (DON) concentrations frequently exceed those of dissolved inorganic nitrogen in aquatic systems. Many components of the DON pool have been shown to supply nitrogen nutrition to phytoplankton and bacteria. Predictions of how global warming and eutrophication will affect metabolic rates and dissolved oxygen dynamics in the future are needed to elucidate their impacts on biodiversity and ecosystem functioning. Here, we experimentally determine simultaneous DON additions and warming on planktonic community metabolism in the Baltic Sea, the largest coastal area suffering from eutrophication-driven hypoxia. Both bacterioplankton community composition and metabolic rates changed in relation to temperature. DON additions from wastewater treatment plant effluents significantly increased the activation energies for community respiration and gross primary production. Activation energies for community respiration were higher than those for gross primary production. Results support the prediction that warming of the Baltic Sea will enhance planktonic respiration rates faster than it will for planktonic primary production. Higher increases in respiration rates than in production may lead to the depletion of the oxygen pool, further aggravating hypoxia in the Baltic Sea.

  • 1323.
    Vasconcelos, Francisco Rivera
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Integrated Science Lab - IceLab, Umeå University, Umeå, Sweden.
    Diehl, Sebastian
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Integrated Science Lab - IceLab, Umeå University, Umeå, Sweden.
    Rodríguez, Patricia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Austral Centre for Scientific Research (CADIC‐CONICET), Ushuaia, Tierra del Fuego, Argentina.
    Hedström, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Karlsson, Jan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Byström, Pär
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Bottom-up and top-down effects of browning and warming on shallow lake food webs2019Inngår i: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 25, s. 504-521Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The productivity and trophic structure of aquatic ecosystems is the result of an interplay between bottom-up and top-down forces that operate both within and across the benthic and pelagic compartments of lake food webs. Contemporary and projected climate changes urge the question how this interplay will be affected by increasing inputs of terrestrial derived, dissolved organic matter (‘browning’) and warming. We addressed this issue by exploring how browning and warming affect the behavior of a relatively simple, conceptual model of a shallow lake food web that is compartmentalized into, dynamically coupled, benthic and pelagic components (abiotic resources, primary producers, grazers, and carnivores). We compared model expectations with the results of a factorial manipulation of browning and warming in a replicated, large-scale field experiment. Both the model and the experiment suggest that browning affects the food web from the bottom-up by reducing light supply to the benthic habitat and increasing nutrient supply to the pelagic habitat, with concomitant decreases of benthic and increases of pelagic primary and secondary production. The model also predicts that warming effects should primarily operate via relaxed top-down control by top consumers in the more productive of the two habitats. The latter was only partially supported by the experimental data, possibly because the model still lacks one or two important trophic links, such as the one from pelagic producers to benthic deposit feeders. We propose that our coupled benthic-pelagic food web model provides a useful conceptual starting point for future theoretical and empirical studies of the impacts of environmental changes on shallow lakes.

  • 1324.
    Vasconcelos, Rivera Francisco
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Diehl, Sebastian
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Rodríguez, Patricia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Austral Centre for Scientific Research (CADIC-CONICET), Ushuaia, Tierra del Fuego, Argentina.
    Karlsson, Jan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Byström, Pär
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Effects of Terrestrial Organic Matter on Aquatic Primary Production as Mediated by Pelagic-Benthic Resource Fluxes2018Inngår i: Ecosystems (New York. Print), ISSN 1432-9840, E-ISSN 1435-0629, Vol. 21, nr 6, s. 1255-1268Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Flows of energy and matter across habitat boundaries can be major determinants of the functioning of recipient ecosystems. It is currently debated whether terrestrial dissolved organic matter (tDOM) is a resource subsidy or a resource subtraction in recipient lakes. We present data from a long-term field experiment in which pelagic phosphorus concentration and whole-ecosystem primary production increased with increasing tDOM input, suggesting that tDOM acted primarily as a direct nutrient subsidy. Piecewise structural equation modeling supports, however, a substantial contribution of a second mechanism: colored tDOM acted also as a resource subtraction by shading benthic algae, preventing them from intercepting nutrients released across the sediment-water interface. Inhibition of benthic algae by colored tDOM thus indirectly promoted pelagic algae and whole-ecosystem primary production. We conclude that cross-ecosystem terrestrial DOM inputs can modify light and nutrient flows between aquatic habitats and alter the relative contributions of benthic and pelagic habitats to total primary production. These results are particularly relevant for shallow northern lakes, which are projected to receive increased tDOM runoff.

  • 1325.
    Vedin, Jörgen
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Rönnmark, Kjell
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysik.
    Bunescu, Costel
    Marghitu, Octav
    Estimating properties of concentrated parallel electric fields from electron velocity distributions2007Inngår i: Geophysical Research Letters, ISSN 0094-8276, E-ISSN 1944-8007, Vol. 34, nr 16, artikkel-id L16107Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Information about the magnitude of the field-aligned potential drop along auroral field lines is usually derived from the velocity distribution of the particles. When the electrons are accelerated by a strong double layer their velocity distribution will have features different from those produced by a weak, spread-out, electric field. Quantifying these features, we obtain information about the strength and thickness of the double layer.

  • 1326. Veen, G. F. (Ciska)
    et al.
    De Long, Jonathan R.
    Kardol, Paul
    Sundqvist, Maja K.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Center for Macroecology, Evolution and Climate, Natural History Museum of Denmark, Univ. of Copenhagen, Copenhagen, Denmark.
    Snoek, L. Basten
    Wardle, David A.
    Coordinated responses of soil communities to elevation in three subarctic vegetation types2017Inngår i: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 126, nr 11, s. 1586-1599Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Global warming has begun to have a major impact on the species composition and functioning of plant and soil communities. However, long-term community and ecosystem responses to increased temperature are still poorly understood. In this study, we used a well-established elevational gradient in northern Sweden to elucidate how plant, microbial and nematode communities shift with elevation and associated changes in temperature in three highly contrasting vegetation types (i.e. heath, meadow and Salix vegetation). We found that responses of both the abundance and composition of microbial and nematode communities to elevation differed greatly among the vegetation types. Within vegetation types, changes with elevation of plant, microbial and nematode communities were mostly linked at fine levels of taxonomic resolution, but this pattern disappeared when coarser functional group levels were considered. Further, nematode communities shifted towards more conservative nutrient cycling strategies with increasing elevation in heath and meadow vegetation. Conversely, in Salix vegetation microbial communities with conservative strategies were most pronounced at the mid-elevation. These results provide limited support for increasing conservative nutrient cycling strategies at higher elevation (i.e. with a harsher climate). Our findings indicate that climate-induced changes in plant community composition may greatly modify or counteract the impact of climate change on soil communities. Therefore, to better understand and predict ecosystem responses to climate change, it will be crucial to consider vegetation type and its specific interactions with soil communities.

  • 1327. Veen, G. F. (Ciska)
    et al.
    Sundqvist, Maja K.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Metcalfe, Daniel
    Wilson, Scott D.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Above-ground and below-ground plant responses to fertilization in two subarctic ecosystems2015Inngår i: Arctic, Antarctic and Alpine research, ISSN 1523-0430, E-ISSN 1938-4246, Vol. 47, nr 4, s. 693-702Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Soil nutrient supply is likely to change in the Arctic due to altered process rates associated with climate change. Here, we compare the responses of herbaceous tundra and birch forest understory to fertilization, considering both above-and below-ground responses. We added nitrogen and phosphorus to plots in both vegetation types for three years near Abisko, northern Sweden, and measured the effect on above-and below-ground plant community properties and soil characteristics. Fertilization increased ground-layer shoot mass, the cover of grasses, and tended to enhance total root length below-ground, while it reduced the cover of low statured deciduous dwarf-shrubs. The only statistically significant interaction between vegetation type and fertilization was for grass cover, which increased twofold in forest understory but sixfold in tundra following fertilization. The lack of interactions for other variables suggests that the ground layers in these contrasting vegetation types have similar responses to fertilization. The nutrient-driven increase in grass cover and species-specific differences in productivity and root characters may alter ecosystem dynamics and C cycling in the long-term, but our study indicates that the response of birch forest understory and tundra vegetation may be consistent.

  • 1328.
    Veenaas, Cathrin
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Developing tools for non-target analysis and digital archiving of organic urban water pollutants2018Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis describes efforts to develop robust methods for the creation and use of digital archives of environmental samples, and proposes guidelines based on the results. Digital archives are repositories that store environmental samples digitally. Traditionally, samples are stored physically in environmental specimen banks over long time periods. However, this has several drawbacks, for example degradation effects and limited accessibility. During the course of my PhD project I developed methods that allow the comprehensive analysis of sewage sludge samples. Sewage sludge is a complex matrix that contains many commercial chemicals. In addition, sewage treatment plants form a link between the human society that generates the sewage and the environment, making sewage sludge a very interesting matrix to analyze. The developed methods enable analysis and subsequent identification of compounds of all sizes and with diverse chemical characteristics. I further explain how unknown compounds can be identified (non-target screening) using mass spectral analysis and several other approaches (e.g. retention indices).

    The thesis is divided into three parts. In the first part, Data Generation, I describe the development of sample preparation methods for analyzing sewage sludge with gas chromatography (GC) and liquid chromatography (LC) coupled to high resolution mass spectrometry (HRMS). For the GC approach, two methods involving use of different extraction techniques, solvents, and matrix reduction techniques are presented while for the LC approach different extraction techniques are compared. The methods have been developed to enable the generation of data suitable for digital archiving. In the second part of the thesis, Data Evaluation, I present ways to find and identify compounds of interest. Firstly, time trend analyses provide a way to prioritize pollutants, for example by focusing on pollutants that are increasing with time. Thousands of compounds with significant time trends were detected and several hundred of them were tentatively identified. Compounds with strong increasing trends included, for example, UV-filters from sunscreens. Secondly, a new retention index system for comprehensive two‑dimensional chromatography (GC×GC) is introduced to characterize compounds in terms of their retention times in the second dimension. The new retention index system is based on co-injection of polyethylene glycols and was validated for various compounds of diverse classes. Thirdly, I tested different ways to predict GC×GC retention times or indices. Those methods include a multivariate prediction (PLS) approach using molecular descriptors, which proved to be the best approach, and use of commercially available software. The last part of my thesis, Data Archiving, discusses requirements to create digital archives and how they can be used. Here I present the current state and options for archiving data files, and give recommendations for each step, from sample collection, through instrumental analysis to storage of the final data.

  • 1329.
    Veenaas, Cathrin
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Bignert, Anders
    Contaminant Research Group, Swedish Museum of Natural History.
    Liljelind, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Nontarget Screening and Time-Trend Analysis of Sewage Sludge Contaminants via Two-Dimensional Gas Chromatography-High Resolution Mass Spectrometry2018Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 52, nr 14, s. 7813-7822Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Nondestructive sample cleanup and comprehensive two-dimensional gas chromatography (GCXGC) high-resolution mass spectrometry (HRMS) analysis generated a massive amount of data that could be used for nontarget screening purposes. We present a data reduction and prioritization strategy that involves time-trend analysis of nontarget data. Sewage sludge collected between 2005 and 2015 in Stockholm (Sweden) was retrieved from an environmental specimen bank, extracted, and analyzed by GCX GC-HRMS. After data alignment features with high blank levels, artifacts and low detection frequency were removed. Features that appeared in four to six out of ten years were reprocessed to fill in gaps. The total number of compounds was reduced by more than 97% from almost 60 000 to almost 1500. The remaining compounds were analyzed for monotonic (log-linear) and nonmonotonic (smoother) time trends. In total, 192 compounds with log-linear trends and 120 compounds with nonmonotonic trends were obtained, respectively. Most compounds described by a log-linear trend exhibited decreasing trends and were traffic-related. Compounds with increasing trends included UV-filters, alkyl-phenols, and flavor and fragrances, which often could be linked to trade statistics. We have shown that nontarget screening and stepwise reduction of data provides a simple way of revealing significant changes in emissions of chemicals in society.

  • 1330.
    Vestergren, Johan
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Ouattara, Korodjouma
    Burkina Faso.
    Schleucher, Jurgen
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Gröbner, Gerhard
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Ilstedt, Ulrik
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Effect of Trees on Forms of Soil Phosphorus in an Agroforestry Parkland in Burkina Faso2014Manuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    Phosphorus is commonly a limiting nutrient for crop production, especially in highly weathered tropical soils. In two semi-arid areas in Burkina Faso with high and low aluminum and iron content respectively, we studied the effect of scattered trees within cropping fields (an agroforestry system called “parklands”) on soils from two areas with high and low aluminum and iron content, respectively. The study focused on different P forms using liquid-state 31P NMR, and their relation to soil chemical properties, determined by XRF. We hypothesized that i) There is generally a difference in P forms between under canopies and in openings outside canopies due to higher input and turnover of organic material close to trees; ii) Close to trees there are more P forms of microbial origin due to the increased activity of the microbial community; iii) This difference is more pronounced in the area with higher content of aluminum and iron. We took topsoil samples under tree canopies as well as outside tree canopies. Our results showed that there were generally low levels of organic carbon and P, but under the canopies of the scattered trees the levels were higher. 31P-NMR showed that soil P was composed of similar ratios of inorganic and organic P as has been observed in other ecosystems, and that the organic P pool was composed of P species commonly observed in soils. NMR also revealed that areas outside the canopies had a less diverse P composition. In the area with high Al/Fe content, microbial activity under trees had a more pronounced effect on the soil P composition, by significantly increasing the amounts of P species of biological origin. In conclusion, the study confirmed the importance of soil organic matter and trees for P availability in semi-arid tropical ecosystems.

  • 1331. Viana, M
    et al.
    Querol, X
    Götschi, T
    Alastuey, A
    Sunyer, J
    Forsberg, Bertil
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Yrkes- och miljömedicin.
    Heinrich, J
    Norbäck, D
    Payo, F
    Maldonado, JA
    Künzli, N
    Source apportionment of ambient PM2.5 at five Spanish centres of the European Community Respiratory Health Survey (ECRHS II)2007Inngår i: Atmospheric Environment, ISSN 1352-2310, E-ISSN 1873-2844, Vol. 41, nr 7, s. 1395-1406Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Fine particulate matter (PM2.5) was sampled at 5 Spanish locations during the European Community Respiratory Health Survey II (ECRHS II). In an attempt to identify and quantify PM2.5 sources, source contribution analysis by principal component analysis (PCA) was performed on five datasets containing elemental composition of PM2.5 analysed by ED-XRF. A total of 4-5 factors were identified at each site, three of them being common to all sites (interpreted as traffic. mineral and secondary aerosols) whereas industrial sources were site-specific. Sea-salt was identified as independent source at all coastal locations except for Barcelona (where it was clustered with secondary aerosols). Despite their typically dominant coarse grain-size distribution, mineral and marine aerosols were clearly observed in PM2.5. Multi-linear regression analysis (MLRA) was applied to the data, showing that traffic was the main source of PM2.5 at the five sites (39-53% of PM2.5, 5.1-12.0 mu g m(-3)), while regional-scale secondary aerosols accounted for 14-34% of PM2.5 (2.6-4.5 mu g m(-3)), mineral matter for 13-31% (2.4-4.6 mu g m(-3)) and sea-salt made up 3-7% of the PM2.5 mass (0.4-1.3 mu g m(-3)). Consequently, despite regional and climatic variability throughout Spain, the same four main PM2.5 emission sources were identified at all the study sites and the differences between the relative contributions of each of these sources varied at most 20%. This would corroborate PM2.5 as a useful parameter for health studies and environmental policy-making, owing to the fact that it is not as subject to the influence of micro-sitting as other parameters such as PM10. African dust inputs were observed in the mineral source, adding on average 4-11 mu g m(-3) to the PM2.5 daily mean during dust outbreaks. On average, levels of Al, Si, Ti and Fe during African episodes were higher by a factor of 2-8 with respect to non-African days, whereas levels of local pollutants (absorption coefficient, S, Pb, Cl) showed smaller variations (factor of 0.5-2).

  • 1332.
    Vickers, Kim
    et al.
    Department of Archaeology, University of Sheffield, UK.
    Buckland, Philip I
    Umeå universitet, Humanistiska fakulteten, Institutionen för idé- och samhällsstudier, Miljöarkeologiska laboratoriet.
    Predicting island beetle faunas by their climate ranges: the tabula rasa/refugia theory in the North Atlantic2015Inngår i: Journal of Biogeography, ISSN 0305-0270, E-ISSN 1365-2699, Vol. 42, nr 11, s. 2031-2048Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Aim: This paper addresses two opposing theories put forward for the origins of the beetle fauna of the North Atlantic islands. The first is that the biota of the isolated oceanic islands of the Faroes, Iceland and Greenland immigrated across a Palaeogene–Neogene land bridge from Europe, and survived Pleistocene glaciations in ameliorated refugia. The second argues for a tabula rasa in which the biota of the islands was exterminated during glaciations and is Holocene in origin. The crux of these theories lies in the ability of the flora and fauna to survive in a range of environmental extremes. This paper sets out to assess the viability of the refugia hypothesis using the climatic tolerances of one aspect of the biota: the beetle fauna. Location: The paper focuses on Iceland, the Faroe Islands and Greenland. Methods: The known temperature requirements of the recorded beetle faunas of the North Atlantic islands were compared with published proxy climate reconstructions for successive climate periods since the severing of a North Atlantic land bridge. We used the MCR (mutual climatic range) method available in the open access BugsCEP database software. Results: We show that most of the MCR faunas of the North Atlantic islands could not have survived in situ since the Palaeogene–Neogene, and are likely to have been exterminated by the Pleistocene glaciations. Main conclusions: The discrepancy between the climatic tolerances of the North Atlantic beetle fauna and the estimated climatic regimes since the severing of a land bridge strongly support the tabula rasa theory and suggests that the North Atlantic coleopteran fauna is Holocene in origin.

  • 1333.
    Viippola, Lotta
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Citizen Science i Abisko: Hur ser förutsättningarna ut inom forskning i nordliga ekosystem?2015Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    In this paper I examine the possibilities for researchers in the field of climate change in the arctic ecosystems to collaborate with people of the common public for monitoring or to answer scientific questions, sometimes called Citizen Science. I have done this by focusing on the research community of Abisko, northern Sweden. I present a number of examples of possible projects that I have collected through literature, interviews and field work with researchers. Furthermore, I argue that Citizen Science projects might be a tool for nature guides in reaching adventurous visitors searching for more understanding of climate change, ecosystems, and who also want to contribute to real science. However, Citizen Science can also be a part of the democratization of a community when local people get engaged. Thus different aspects of Citizen Science are suitable for different target groups.

  • 1334. Viipsi, K.
    et al.
    Sjöberg, S.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Tõnsuaadu, K.
    Shchukarev, Andrey
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Cd2+ and Zn2+ sorption on apatite in the presence of EDTA and humic substance2013Inngår i: Proceedings of the 16th International Conference on Heavy Metals in the Environment / [ed] Pirrone, N, EDP Sciences, 2013, artikkel-id 01008Konferansepaper (Fagfellevurdert)
    Abstract [en]

    The sorption of Cd2+ and Zn2+ on hydroxyapatite [HAP-Ca-10(PO4)(6)(OH)(2)] and fluorapatite [FAP-Ca-10(PO4)(6)(F)(2)] with different specific surface area and stoichiometry was investigated in batch experiments in the pH range 4 to 11 (25 degrees C; 0.1 M KNO3). The impact of different conditions was concerned: solution pH, the presence of complexing ligands (EDTA and humic substance) and competing metal ions, as well as reaction kinetic and equilibrium conditions. To evaluate the reversibility of Cd2+ sorption onto HAP, desorption characteristics in water, Ca, EDTA, and HUM-solutions were determined. Additionally to solution analysis the surface composition of solid phases was analysed by X-Ray Photoelectron Spectroscopy (XPS). The information from the chemical analyses was used to design an equilibration model that takes into account dissolution, surface potential, solution and surface complexation, as well as possible phase transformations. It was revealed that apatites effectively sorb Cd2+ and Zn2+ by ion exchange reactions on surface by formation of new surface phases. Using XPS the formation of a Me-enriched HAP surface was found, which was interpreted as the formation of a solid solution with the general formula: Ca8.4-xMex(HPO4)(1.6)(PO4)(4.4)(OH)(0.4). In a binary solution (Cd+ Zn) the competition of metals reduced individual sorbed amount compared with the single component solutions but the total adsorption maximum was approximately constant. The presence of EDTA reduces the metal sorption on apatite due to [CdEDTA](2)- and [ZnEDTA] 2-complexes and increases apatite solubility due to [CaEDTA](2)-complex formation. The dissolved humic substance was bound on apatite in suspensions but the amount of Cd2+ bound was not changed. The results showed that the solution pH and the presence of complexing ligands have a significant effect on heavy metal sorption on apatite and must be considered if apatites are used as remediation agent. The proposed model can be used to predict apatite dissolution and surface phase transformations in the presence of metal ions and EDTA.

  • 1335.
    Viitasalo, Markku
    et al.
    SYKE.
    Blenckner, Thorsten
    Stockholms universitet.
    Gårdmark, Anna
    Sveriges Lantbruksuniversitet.
    Kaartokallio, Hermanni
    Kautsky, Lena
    Stockholms universitet.
    Kuosa, Harri
    SYKE, Finland.
    Lindegren, Martin
    Norkko, Alf
    Olli, Kalle
    Wikner, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Environmental Impacts—Marine Ecosystems2015Inngår i: Second Assessment of Climate Change for the Baltic Sea Basin / [ed] The BACC II Author Team, London: Springer, 2015, s. 363-380Kapittel i bok, del av antologi (Annet vitenskapelig)
    Abstract [en]

    Increase in sea surface temperature is projected to change seasonal succession and induce dominance shifts in phytoplankton in spring and promote the growth of cyanobacteria in summer. In general, climate change is projected to worsen oxygen conditions and eutrophication in the Baltic Proper and the Gulf of Finland. In the Gulf of Bothnia, the increasing freshwater discharge may increase the amount of dissolved organic carbon (DOC) in the water and hence reduce phytoplankton productivity. In winter, reduced duration and spatial extent of sea ice will cause habitat loss for ice-dwelling organisms and probably induce changes in nutrient dynamics within and under the sea ice. The projected salinity decline will probably affect the functional diversity of the benthic communities and induce geographical shifts in the distribution limits of key species such as bladder wrack and blue mussel. In the pelagic ecosystem, the decrease in salinity together with poor oxygen conditions in the deep basins will negatively influence the main Baltic Sea piscivore, cod. This has been suggested to cause cascading effects on clupeids and zooplankton.

  • 1336.
    Viklund, Kristina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Människan, näringen och havet2017Rapport (Annet (populærvitenskap, debatt, mm))
    Abstract [sv]

    De senaste 100 åren har tillförseln av kväve och fosfor till Östersjön ökat. Från 1950-talet blev ökningen särskilt markant, vilket också ledde till ökande problem med övergödning i havet. Detta uppmärksammades ordentligt under 1970-talet och en omfattande och systematisk övervakning av havsmiljöns tillstånd initierades.

    Åtgärder sattes in, från början främst med fokus på punktutsläpp från avlopp och industrier och sedan 1990-talet har belastningen av både fosfor och kväve minskat. Under senare tid har åtgärder även satts in för de mer svårhanterliga diffusa utsläppen, som till övervägande del härrör från jordbruket.

    Östersjöns speciella förhållanden gör dock att förbättringen tar tid, och det är först de senaste åren som ekosystemet börjat visa tecken på återhämtning. Kostnader för åtgärder är höga, och frågan är om det ens finns förutsättningar att nå de högt uppsatta målen. Var ska åtgärder sättas in, vad finns att göra, och vem ska göra det?

    Och samtidigt – vad kostar det att inte förbättra situationen, i termer av minskad fiskproduktion, minskade intäkter av turism i havsbandet och ett förändrat ekosystem? Problemet är komplext, och för att komma till rätta med det krävs samarbete mellan nio vitt skilda länder, som alla är med och påverkar miljötillståndet i det gemensamma innanhavet Östersjön.

  • 1337.
    Vincent, Andrea G
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Schleucher, Jürgen
    Umeå universitet, Medicinska fakulteten, Institutionen för medicinsk kemi och biofysik.
    Gröbner, Gerhard
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Vestergren, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Persson, Per
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Jansson, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Giesler, Reiner
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Changes in organic phosphorus composition in boreal forest humus soils: the role of iron and aluminium2012Inngår i: Biogeochemistry, ISSN 0168-2563, E-ISSN 1573-515X, Vol. 108, nr 1-3, s. 485-499Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Organic phosphorus (P) is an important component of boreal forest humus soils, and its concentration has been found to be closely related to the concentration of iron (Fe) and aluminium (Al). We used solution and solid state 31P NMR spectroscopy on humus soils to characterize organic P along two groundwater recharge and discharge gradients in Fennoscandian boreal forest, which are also P sorption gradients due to differences in aluminium (Al) and iron (Fe) concentration in the humus. The composition of organic P changed sharply along the gradients. Phosphate diesters and their degradation products, as well as polyphosphates, were proportionally more abundant in low Al and Fe sites, whereas phosphate monoesters such as myo-, scyllo- and unknown inositol phosphates dominated in high Al and Fe soils. The concentration of inositol phosphates, but not that of diesters, was positively related to Al and Fe concentration in the humus soil. Overall, in high Al and Fe sites the composition of organic P seemed to be closely associated with stabilization processes, whereas in low Al and Fe sites it more closely reflected inputs of organic P, given the dominance of diesters which are generally assumed to constitute the bulk of organic P inputs to the soil. These gradients encompass the broad variation in soil properties detected in the wider Fennoscandian boreal forest landscape, as such our findings provide insight into the factors controlling P biogeochemistry in the region but should be of relevance to boreal forests elsewhere.

  • 1338.
    Vinterek, Sebastian
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Rening av lakvatten vid deponin Degermyran i Skellefteå kommun: Utvärdering av nuvarande reningseffekt och simulering av mängden bildat lakvatten under 2000-talets klimatförändringar2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    At Degermyran landfill, situated in the municipal Skellefteå, a leachate treatment system was installed in 2005. One of the aims of this study was to investigate how well the treatment system works by using data from chemical measurements made on the leachate before and after treatment. Further this study had the purpose of investigating how the predicted climate changes of the 21st century will affect the amount of leachate generated at Degermyran by using a modified version of Thornthwaites water balance model. The treatment system has the ability of reducing manganese by 90 %, nitrogen by 73 % och TOC by 79 %. By the turn of this century the amount of precipitation that percolates the waste at Degermyran will be between 254 and 298 mm, depending on the amount of greenhouse gases that will be released in the future to come. The conclusions from this study are that the leachate treatment system reduces the levels of the investigated substances and that the amount of leachate produced at Degermyran will increase. To further investigate the efficiency of the leachate treatment system, flow proportionate measurements of the leachate chemistry could be adopted. If accurate flow measurements of the amount of generated leachate were performed the reliability of the used water balance model could be assessed.

  • 1339. Violante, Antonio
    et al.
    Del Gaudio, Stefania
    Pigna, Massimo
    Ricciardella, Mariarosaria
    Banerjee, Dipanjan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Coprecipitation of arsenate with metal oxides. 2. Nature, mineralogy, and reactivity of iron(III) precipitates2007Inngår i: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 41, nr 24, s. 8275-8280Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Coprecipitation of arsenic with iron or aluminum occurs in natural environments and is a remediation technology used to remove this toxic metalloid from drinking water and hydrometallurgical solutions. In this work, we studied the nature, mineralogy, and reactivity toward phosphate of iron-arsenate coprecipitates formed at As(V)/Fe(III) molar ratios (R) of 0, 0.01, or 0.1 and at pH 4.0, 7.0, and 10.0 aged for 30 or 210 days at 50 degrees C and studied the desorption of arsenate. At R = 0, goethite and hematite (with ferrihydrite at pH 4.0 and 7.0) crystallized, whereas at R = 0.01, the formation of ferrihydrite increased and hematite crystallization was favored over goethite. In some samples, the morphology of hematite changed from rounded platy crystals to ellipsoids. At R = 0.1, ferrihydrite formed in all the coprecipitates and remained unchanged even after 210 days of aging. The surface area and chemical composition of the precipitates were affected by pH, R, and aging. Chemical dissolution of the samples showed that arsenate was present mainly in ferrihydrite, but at R = 0.01, it was partially incorporated into the structures of crystalline Fe oxides. The sorption of phosphate on to the coprecipitates was affected not only by the mineralogy and surface area of the samples but also by the amounts of arsenate present in the oxides. The samples formed at pH 4.0 and 7.0 and at R = 0.1 sorbed lower amounts of phosphate than the precipitates obtained at R = 0 or 0.01, despite the former having a larger surface area and showing only a presence of short-range ordered materials. This is mainly due to the fact that in the coprecipitates at R = 0.1 arsenate occupied many sorption sites, thus preventing phosphate sorption. Less than 20% of the arsenate present in the coprecipitates formed at R = 0.1 was removed by phosphate and more from the samples synthesized at pH 7.0 or 10.0 than at pH 4.0. Moreover, we found that more arsenate was desorbed by phosphate from a ferrihydrite on which arsenate was added than from an iron-arsenate coprecipitate, attributed to the partial occlusion of some arsenate anions into the framework of the coprecipitate. XPS analyses confirmed these findings.

  • 1340.
    Vogel, Hendrik
    et al.
    Institute of Geology and Mineralogy, University of Cologne, Köln, Germany ; Institute of Geological Sciences & Oeschger Centre for Climate Change Research, University of Bern, Switzerland .
    Meyer-Jacob, Carsten
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Melles, Martin
    Brigham-Grette, Julie
    Andreev, Andrei
    Wennrich, Volker
    Tarasov, Pavel
    Rosen, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Detailed insight into Arctic climatic variability during MIS 11c at Lake El'gygytgyn, NE Russia2013Inngår i: Climate of the Past, ISSN 1814-9324, E-ISSN 1814-9332, Vol. 9, nr 4, s. 1467-1479Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Here we present a detailed multi-proxy record of the climate and environmental evolution at Lake El'gygytgyn, Far East Russian Arctic during the period 430-395 ka covering the marine isotope stage (MIS) 12/11 transition and the thermal maximum of super interglacial MIS 11c. The MIS 12/11 transition at Lake El'gygytgyn is characterized by initial warming followed by a cold reversal implying similarities to the last deglaciation. The thermal maximum of MIS 11c is characterized by full and remarkably stable interglacial conditions with mean temperatures of the warmest month (MTWM) ranging between ca. 10-15 degrees C; annual precipitation (PANN) ranging between ca. 300-600 mm; strong in-lake productivity coinciding with dark coniferous forests in the catchment; annual disintegration of the lake ice cover; and full mixis of the water column. Such conditions persisted, according to our age model, for ca. 27 +/- 8 kyr between ca. 425-398 ka. The Lake El'gygytgyn record closely resembles the climate pattern recorded in Lake Baikal (SE Siberia) sediments and Antarctic ice cores, implying interhemispheric climate connectivity during MIS 11c.

  • 1341. Vogel, Hendrik
    et al.
    Meyer-Jacob, Carsten
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Thöle, Lena
    Lippold, Jörg A.
    Jaccard, Samuel L.
    Quantification of biogenic silica by means of Fourier transform infrared spectroscopy (FTIRS) in marine sediments2016Inngår i: Limnology and Oceanography: Methods, ISSN 1541-5856, E-ISSN 1541-5856, Vol. 14, nr 12, s. 828-838Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Due to the major role played by diatoms in the marine biological pump, opal/biogenic silica (bSi) has a strong potential as a proxy for paleoproduction reconstructions. Here, we present a detailed evaluation of the independent Fourier transform infrared spectroscopy (FTIRS) calibration introduced by Meyer-Jacob et al. (2014a), which is based on synthetic sediment mixtures with known concentrations of bSi and the application of partial least squares (PLS) regression, for the determination of bSi in marine sediments. To test the robustness of the FTIRS calibration for marine samples we selected 199 globally distributed samples, with available wet chemically inferred bSi concentrations and compared the results of both methods. We observe that the spectral characteristics in marine samples are comparable to those reported for a synthetic FTIR spectrum composed solely of spectral features in quartz, biogenic silica, and calcite. FTIRS-inferred and wet-chemically measured bSi concentrations for the set of 199 marine sediment samples are strongly correlated (R-2 = 0.87; RMSE = 5.27%). Together with the high reproducibility of bSi values by the independent calibration our results corroborate the applicability of the independent FTIRS bSi calibration for quantification in marine samples. This together with the succinct sample preparation procedure, rapid analysis, reduced consumable and machine maintenance costs makes FTIRS a powerful and robust alternative for the quantitative analysis of bSi in marine sediments.

  • 1342.
    Vogel, Hendrik
    et al.
    Institute of Geological Sciences, University of Bern, Bern, Switzerland.
    Wagner, Bernd
    Institute of Geology and Mineralogy, University of Cologne, Köln, Germany.
    Rosen, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Lake Floor Morphology and Sediment Architecture of Lake Tornetrask, Northern Sweden2013Inngår i: Geografiska Annaler. Series A, Physical Geography, ISSN 0435-3676, E-ISSN 1468-0459, Vol. 95, nr 2, s. 159-170Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Here we present datasets from a hydroacoustic survey in July 2011 at Lake Tornetrask, northern Sweden. Our hydroacoustic data exhibit lake floor morphologies formed by glacial erosion and accumulation processes, insights into lacustrine sediment accumulation since the beginning of deglaciation, and information on seismic activity along the Parvie Fault. Features of glacial scouring with a high-energy relief, steep slopes, and relative reliefs of more than 50m are observed in the large W-basin. The remainder of the lacustrine subsurface appears to host a broad variety of well preserved formations from glacial accumulation related to the last retreat of the Fennoscandian ice sheet. Deposition of glaciolacustrine and lacustrine sediments is focused in areas situated in proximity to major inlets. Sediment accumulation in distal areas of the lake seldom exceeds 2m or is not observable. We assume that lack of sediment deposition in the lake is a result of different factors, including low rates of erosion in the catchment, a previously high lake level leading to deposition of sediments in higher elevated paleodeltas, tributaries carrying low suspension loads as a result of sedimentation in upstream lakes, and an overall low productivity in the lake. A clear off-shore trace of the Parvie Fault could not be detected from our hydroacoustic data. However, an absence of sediment disturbance in close proximity to the presumed fault trace implies minimal seismic activity since deposition of the glaciolacustrine and lacustrine sediments.

  • 1343. Volchko, Yevheniya
    et al.
    Norrman, Jenny
    Bergknut, Magnus
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen. Envix, Umeå.
    Rosen, Lars
    Soderqvist, Tore
    Incorporating the soil function concept into sustainability appraisal of remediation alternatives2013Inngår i: Journal of Environmental Management, ISSN 0301-4797, E-ISSN 1095-8630, Vol. 129, s. 367-376Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Soil functions are critical for ecosystem survival and thus for an ecosystem's provision of services to humans. This is recognized in the proposed EU Soil Framework Directive from 2006, which lists seven important soil functions and services to be considered in a soil management practice. Emerging regulatory requirements demand a holistic view on soil evaluation in remediation projects. This paper presents a multi-scale, structured and transparent approach for incorporating the soil function concept into sustainability appraisal of remediation alternatives using a set of ecological, socio-cultural and economic criteria. The basis for the presented approach is a conceptualization of the linkages between soil functions and ecosystem services connected to with the sustainability paradigm. The approach suggests using (1) soil quality indicators (i.e. physical, chemical and biological soil properties) for exploring the performance of soil functions at the site level, and (2) soil service indicators (i.e. value-related measurements) for evaluating the performance of services resulting from soil functions across all levels of the spatial scale. The suggested approach is demonstrated by application in a Multi-Criteria Decision Analysis (MCDA) framework for sustainability appraisals of remediation alternatives. Further, the possibilities of using soil quality indicators for soil function evaluation are explored by reviewing existing literature on potential negative and positive effects of remediation technologies on the functionality of the treated soil. The suggested approach for including the soil function concept in remediation projects is believed to provide a basis for better informed decisions that will facilitate efficient management of contaminated land and to meet emerging regulatory requirements on soil protection.

  • 1344. Volchko, Yevheniya
    et al.
    Norrman, Jenny
    Rosen, Lars
    Bergknut, Magnus
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Josefsson, Sarah
    Soderqvist, Tore
    Norberg, Tommy
    Wiberg, Karin
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Using soil function evaluation in multi-criteria decision analysis for sustainability appraisal of remediation alternatives2014Inngår i: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 485, s. 785-791Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Soil contamination is one of the major threats constraining proper functioning of the soil and thus provision of ecosystem services. Remedial actions typically only address the chemical soil quality by reducing total contaminant concentrations to acceptable levels guided by land use. However, emerging regulatory requirements on soil protection demand a holistic view on soil assessment in remediation projects thus accounting for a variety of soil functions. Such a view would require not only that the contamination concentrations are assessed and attended to, but also that other aspects are taking into account, thus addressing also physical and biological as well as other chemical soil quality indicators (SQIs). This study outlines how soil function assessment can be a part of a holistic sustainability appraisal of remediation alternatives using multi-criteria decision analysis (MCDA). The paper presents a method for practitioners for evaluating the effects of remediation alternatives on selected ecological soil functions using a suggested minimum data set (MDS) containing physical, biological and chemical SQIs. The measured SQls are transformed into sub-scores by the use of scoring curves, which allows interpretation and the integration of soil quality data into the MCDA framework. The method is demonstrated at a study site (Marieberg, Sweden) and the results give an example of how soil analyses using the suggested MDS can be used for soil function assessment and subsequent input to the MCDA framework.

  • 1345.
    von Zweigbergk, Peter
    et al.
    National Institute for Working Life, Umeå.
    Lindahl, Roger
    National Institute for Working Life, Umeå.
    Östin, Anders
    National Institute for Working Life, Umeå.
    Ekman, Jenny
    National Institute for Working Life, Umeå.
    Levin, Jan-Olof
    National Institute for Working Life, Umeå.
    Development of a diffusive sampling method for determination of methyl isocyanate in air2002Inngår i: Journal of Environmental Monitoring, ISSN 1464-0325, E-ISSN 1464-0333, Vol. 4, nr 5, s. 663-666Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A diffusive sampling method for determination of methyl isocyanate in air has been developed. A glass fibre filter impregnated with 1-(2-methoxyphenyl)piperazine in a commercially available diffusive sampling device was used to collect methyl isocyanate and the derivative formed was analysed with LC-MS/MS. The sampling rate was determined to be 15.6 ml min(-1), with a relative standard deviation of 7.3%. The sampler was validated for sampling periods from 15 min to 8 h, for relative humidities from 20% to 80% and for concentrations from I to 46 microg m(-3). A field validation was also made and the diffusive sampling results showed no difference compared to a pumped reference method. The impregnated filters have to be stored apart from the diffusive sampler housing and loaded into the sampler prior to each sampling.

  • 1346. Vorobyev, Sergey N.
    et al.
    Pokrovsky, Oleg S.
    Kolesnichenko, Larisa G.
    Manasypov, Rinat M.
    Shirokova, Liudmila S.
    Karlsson, Jan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Climate Impacts Research Centre (CIRC), Umeå University, Umeå, Sweden.
    Kirpotin, Sergey N.
    Biogeochemistry of dissolved carbon, major, and trace elements during spring flood periods on the Ob River2019Inngår i: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, Vol. 33, nr 11, s. 1579-1594Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Detailed knowledge of the flood period of Arctic rivers remains one of the few factors impeding rigorous prediction of the effect of climate change on carbon and related element fluxes from the land to the Arctic Ocean. In order to test the temporal and spatial variability of element concentration in the Ob River (western Siberia) water during flood period and to quantify the contribution of spring flood period to the annual element export, we sampled the main channel year round in 2014-2017 for dissolved C, major, and trace element concentrations. We revealed high stability (approximately <= 10% relative variation) of dissolved C, major, and trace element concentrations in the Ob River during spring flood period over a 1-km section of the river channel and over 3 days continuous monitoring (3-hr frequency). We identified two groups of elements with contrasting relationship to discharge: (a) DIC and soluble elements (Cl, SO4, Li, B, Na, Mg, Ca, P, V, Cr, Mn, As, Rb, Sr, Mo, Ba, W, and U) negatively correlated (p < 0.05) with discharge and exhibited minimal concentrations during spring flood and autumn high flow and (b) DOC and particle-reactive elements (Al, Fe, Ti, Y, Zr, Nb, Cs, REEs, Hf, Tl, Pb, and Th), some nutrients (K), and metalloids (Ge, Sb, and Te), positively correlated (p < 0.05) with discharge and showed the highest concentrations during spring flood. We attribute the decreased concentration of soluble elements with discharge to dilution by groundwater feeding and increased concentration of DOC and particle-reactive metals with discharge to leaching from surface soil, plant litter, and suspended particles. Overall, the present study provides first-order assessment of fluxes of major and trace elements in the middle course of the Ob River, reveals their high temporal and spatial stability, and characterizes the mechanism of river water chemical composition acquisition.

  • 1347. Vrede, Tobias
    et al.
    Drakare, Stina
    Eklöv, Peter
    Hein, Arne
    Liess, Antonia
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Olsson, Jens
    Persson, Jonas
    Quevedo, Mario
    Ragnarsson Stabo, Henrik
    Svanbäck, Richard
    Ecological stoichiometry of Eurasian perch: intraspecific variation due to size, habitat and diet2011Inngår i: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 120, nr 6, s. 886-896Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The turnover and distribution of energy and nutrients in food webs is influenced by consumer stoichiometry. Although the stoichiometry of heterotrophs is generally considered to vary only little, there may be intraspecific variation due to factors such as habitat, resources, ontogeny and size. We examined intraspecific variation in Eurasian perch Perca fluviatilis stoichiometry, a common species that exhibits habitat and resource specialization, ontogenetic niche shifts and a large size range. This study investigated the elemental stoichiometry of a wide size range of perch from littoral and pelagic habitats. The mean C:N:P stoichiometry of whole perch was 37:9:1 (molar ratios). However, %C, %P, C:N, C:P and N:P varied with size, morphology, habitat and diet category. These factors together explained 24–40% of the variation in C:N:P stoichiometry. In contrast, perch stoichiometry was not related to diet stoichiometry, suggesting that the former is homeostatically regulated. The results suggest that the high P content of perch may result in stoichiometric constraints on the growth of non-piscivorous perch, and that piscivory is an efficient strategy for acquiring P. Resource polymorphism, individual diet specialization and intraspecific size variation are widespread among animals. Thus changes in stoichiometry with size, habitat, morphology and resource use, and therefore also stoichiometric demands, are probably common.

  • 1348.
    Väisänen, Maria
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Arctic Centre, University of Lapland, Rovaniemi, Finland.
    Krab, Eveline J.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Dorrepaal, Ellen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Carbon dynamics at frost-patterned tundra driven by long-term vegetation change rather than by short-term non-growing season warming2017Inngår i: Biogeochemistry, ISSN 0168-2563, E-ISSN 1573-515X, Vol. 136, nr 1, s. 103-117Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Frost-patterned grounds, such as mostly barren frost boils surrounded by denser vegetation, are typical habitat mosaics in tundra. Plant and microbial processes in these habitats may be susceptible to short-term warming outside the growing season, while the areal cover of barren frost boils has decreased during the past decades due to climate warming-induced shrub expansion. The relative importance of such short-term and long-term climate impacts on carbon (C) dynamics remains unknown. We measured ecosystem CO2 uptake and release (in the field), microbial respiration (in the laboratory), as well as microbial biomass N and soil extractable N in frost boils and the directly adjacent heath in late spring and late summer. These habitats had been experimentally warmed with insulating fleeces from late September until late May for three consecutive years, which allowed us to investigate the direct short-term effects of warming and longer-term, indirect climate effects via vegetation establishment into frost boils. Non-growing season warming increased C uptake at the frost boils in late spring and decreased it in late summer, while the timing and direction of responses was opposite for the heath. Experimental warming had no effects on microbial or ecosystem C release or soil N at either of the habitats. However, C cycling was manifold higher at the heath compared to the frost boils, likely because of a higher SOM stock in the soil. Short-term climate change can thus directly alter ecosystem C uptake at frost-patterned grounds but will most likely not affect microbial C release. We conclude that the C dynamics at frost-patterned grounds under a changing climate depend most strongly on the potential of vegetation to encroach into frost boils in the long-term.

  • 1349. Väisänen, Maria
    et al.
    Martz, Françoise
    Kaarlejärvi, Elina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Julkunen-Tiitto, Riitta
    Stark, Sari
    Phenolic responses of mountain crowberry (Empetrum nigrum ssp. hermaphroditum) to global climate change are compound specific and depend on grazing by reindeer (Rangifer tarandus)2013Inngår i: Journal of Chemical Ecology, ISSN 0098-0331, E-ISSN 1573-1561, Vol. 39, nr 11-12, s. 1390-1399Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Mountain crowberry (Empetrum nigrum ssp. hermaphroditum) is a keystone species in northern ecosystems and exerts important ecosystem-level effects through high concentrations of phenolic metabolites. It has not been investigated how crowberry phenolics will respond to global climate change. In the tundra, grazing by reindeer (Rangifer tarandus) affects vegetation and soil nutrient availability, but almost nothing is known about the interactions between grazing and global climate change on plant phenolics. We performed a factorial warming and fertilization experiment in a tundra ecosystem under light grazing and heavy grazing and analyzed individual foliar phenolics and crowberry abundance. Crowberry was more abundant under light grazing than heavy grazing. Although phenolic concentrations did not differ between grazing intensities, responses of crowberry abundance and phenolic concentrations to warming varied significantly depending on grazing intensity. Under light grazing, warming increased crowberry abundance and the concentration of stilbenes, but decreased e.g., the concentrations of flavonols, condensed tannins, and batatasin-III, resulting in no change in total phenolics. Under heavy grazing, warming did not affect crowberry abundance, and induced a weak but consistent decrease among the different phenolic compound groups, resulting in a net decrease in total phenolics. Our results show that the different phenolic compound groups may show varying or even opposing responses to warming in the tundra at different levels of grazing intensity. Even when plant phenolic concentrations do not directly respond to grazing, grazers may have a key control over plant responses to changes in the abiotic environment, reflecting multiple adaptive purposes of plant phenolics and complex interactions between the biotic and the abiotic factors.

  • 1350.
    Waara, Martin
    et al.
    Swedish Institute of Space Physics, Kiruna, Sweden.
    Slapak, R
    Swedish Institute of Space Physics, Kiruna, Sweden.
    Nilsson, H
    Swedish Institute of Space Physics, Kiruna, Sweden.
    Stenberg, G
    Swedish Institute of Space Physics, Kiruna, Sweden.
    André, M
    Swedish Institute of Space Physics, Uppsala, Sweden.
    Barghouthi, IA
    Al Quds University, Jerusalem, Palestine.
    Statistical evidence for O+ energization and outflow caused by wave-particle interaction in the high altitude cusp and mantle2011Inngår i: Annales Geophysicae, ISSN 0992-7689, E-ISSN 1432-0576, Vol. 29, s. 945-954Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We present a statistical study of the low (<1 Hz) frequency electric and magnetic field spectral densities observed by Cluster spacecraft in the high altitude cusp and mantle region. At the O+ gyrofrequency (0.02–0.5 Hz) for this region the electric field spectral density is on average 0.2–2.2 (mV m−1)2 Hz−1, implying that resonant heating at the gyrofrequency can be intense enough to explain the observed O+ energies of 20–1400 eV. The relation between the electric and magnetic field spectral densities results in a large span of phase velocities, from a few hundred km s−1 up to a few thousand km s−1. In spite of the large span of phase velocity, the ratio between the calculated local Alfvén velocity and the estimated phase velocity is close to unity. We provide average values of a coefficient describing diffusion in ion velocity space at different altitudes, which can be used in studies of ion energization and outflow. The observed average waves can explain the average O+ energies measured in the high altitude (8–15 RE) cusp/mantle region of the terrestrial magnetosphere according to our test particle calculations.

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