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  • 1.
    Abascal, Angela
    et al.
    University of Navarra, Spain; University of Twente, Netherlands.
    Georganos, Stefanos
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Kuffer, Monika
    University of Twente, Netherlands.
    Vanhuysse, Sabine
    Université libre de Bruxelles (ULB), Belgium.
    Thomson, Dana
    University of Twente, Netherlands.
    Wang, Jon
    University of Twente, Netherlands.
    Manyasi, Lawrence
    Community Researcher Non-affiliated, Nairobi, Kenya.
    Otunga, Daniel Manyasi
    Community Researcher Single Mother Association of Kenya, Nairobi, Kenya.
    Ochieng, Brighton
    Community Researcher Non-affiliated, Nairobi, Kenya.
    Ochieng, Treva
    Community Researcher Non-affiliated, Nairobi, Kenya.
    Klinnert, Jorge
    University of Maryland, USA.
    Wolff, Eléonore
    Université libre de Bruxelles (ULB), Belgium.
    Making Urban Slum Population Visible: Citizens and Satellites to Reinforce Slum Censuses2024In: Urban Inequalities from Space: Earth Observation Applications in the Majority World / [ed] Monika Kuffer, Stefanos Georganos, Springer, 2024, Vol. 26, p. 287-302Chapter in book (Refereed)
    Abstract [en]

    In response to the “Leave No One Behind” principle (the central promise of the 2030 Agenda for Sustainable Development), reliable estimate of the total number of citizens living in slums is urgently needed but not available for some of the most vulnerable communities. Not having a reliable estimate of the number of poor urban dwellers limits evidence-based decision-making for proper resource allocation in the fight against urban inequalities. From a geographical perspective, urban population distribution maps in many low- and middle-income cities are most often derived from outdated or unreliable census data disaggregated by coarse administrative units. Moreover, slum populations are presented as aggregated within bigger administrative areas, leading to a large diffuse in the estimates. Existing global and open population databases provide homogeneously disaggregated information (i.e. in a spatial grid), but they mostly rely on census data to generate their estimates, so they do not provide additional information on the slum population. While a few studies have focused on bottom-up geospatial models for slum population mapping using survey data, geospatial covariates, and earth observation imagery, there is still a significant gap in methodological approaches for producing precise estimates within slums. To address this issue, we designed a pilot experiment to explore new avenues. We conducted this study in the slums of Nairobi, where we collected in situ data together with slum dwellers using a novel data collection protocol. Our results show that the combination of satellite imagery with in situ data collected by citizen science paves the way for generalisable, gridded estimates of slum populations. Furthermore, we find that the urban physiognomy of slums and population distribution patterns are related, which allows for highlighting the diversity of such patterns using earth observation within and between slums of the same city. 

  • 2.
    Abbott, Jessica K.
    et al.
    Lund University.
    Chippindale, Adam K.
    Queens University, Kingston, CAN.
    Morrow, Edward H. (Ted)
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    The microevolutionary response to male-limited X-chromosome evolution in Drosophila melanogaster reflects macroevolutionary patterns2020In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 33, no 6, p. 738-750Article in journal (Refereed)
    Abstract [en]

    Due to its hemizygous inheritance and role in sex determination, the X-chromosome is expected to play an important role in the evolution of sexual dimorphism and to be enriched for sexually antagonistic genetic variation. By forcing the X-chromosome to only be expressed in males over >40 generations, we changed the selection pressures on the X to become similar to those experienced by the Y. This releases the X from any constraints arising from selection in females and should lead to specialization for male fitness, which could occur either via direct effects of X-linked loci or trans-regulation of autosomal loci by the X. We found evidence of masculinization via up-regulation of male-benefit sexually antagonistic genes and down-regulation of X-linked female-benefit genes. Potential artefacts of the experimental evolution protocol are discussed and cannot be wholly discounted, leading to several caveats. Interestingly, we could detect evidence of microevolutionary changes consistent with previously documented macroevolutionary patterns, such as changes in expression consistent with previously established patterns of sexual dimorphism, an increase in the expression of metabolic genes related to mito-nuclear conflict and evidence that dosage compensation effects can be rapidly altered. These results confirm the importance of the X in the evolution of sexual dimorphism and as a source for sexually antagonistic genetic variation and demonstrate that experimental evolution can be a fruitful method for testing theories of sex chromosome evolution.

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  • 3.
    Abecasis, David
    et al.
    University of the Algarve, Portugal.
    Steckenreuter, Andre
    University of the Azores, Portugal.
    Reubens, Jan
    Flanders Marine Institute, Belgium.
    Aaestrup, Kim
    DTU, Denmark.
    Alos, Josep
    Instituto Mediterráneo de Estudios Avanzados (CSIC-UIB), Spain.
    Badalamenti, Fabio
    CNR-IAMC, Italy.
    Bajona, Lenore
    Dalhousie University, Canada.
    Boylan, Patrick
    Loughs Agency, UK.
    Deneudt, Klaas
    Flanders Marine Institute, Belgium.
    Greenberg, Larry
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Brevé, Niels
    Sportfisserij Nederland, The Netherlands.
    Hernandez, Francisco
    Flanders Marine Institute, Belgium.
    Humphries, Nick
    The Marine Biological Association of the U.K, UK.
    Meyer, Carl
    University of Hawai’i at Mānoa, USA.
    Sims, David
    University of Southampton, UK.
    Thorstad, Eva B.
    Norwegian Institute for Nature Research (NINA), Norway.
    Walker, Alan M.
    Centre for Environment, Fisheries and Aquaculture Science (Cefas), UK.
    Whoriskey, Fred
    Dalhousie University, Canada.
    Alfonso, Pedro
    University of the Azores, Portugal.
    A review of acoustic telemetry in Europe and the need for a regional aquatic telemetry network2018In: Animal Biotelemetry, E-ISSN 2050-3385, Vol. 6, article id 12Article in journal (Refereed)
    Abstract [en]

    Background: Globally, there are a large and growing number of researchers using biotelemetry as a tool to studyaquatic animals. In Europe, this community lacks a formal network structure. The aim of this study is to review the useof acoustic telemetry in Europe and document the contribution of cross-boundary studies and inter-research groupcollaborations. Based on this, we explore the potential benefits and challenges of a network approach to identifyfuture priorities and best practices for aquatic biotelemetry research in Europe.

    Results: Over the past decade, there was an approximately sevenfold increase in the number of acoustic telemetrystudies published on marine and diadromous species in Europe compared to a sixfold increase globally. Over 90%of these studies were conducted on fishes and undertaken in coastal areas, estuaries, or rivers. 75% of these studieswere conducted by researchers based in one of five nations (Norway, UK, France, Portugal, and Spain) and, eventhough 34% were based on collaborations between scientists from several countries, there was only one study withan acoustic receiver array that extended beyond the borders of a single country. In recent years, acoustic telemetryin European waters has evolved from studying behavioural aspects of animals (82.2%), into more holistic approachesaddressing management-related issues (10%), tagging methods and effects (5%), and technology and data analysisdevelopment (2.8%).

    Conclusions: Despite the increasing number of publications and species tracked, there is a prominent lack ofplanned and structured acoustic telemetry collaborations in Europe. A formal pan-European network structure wouldpromote the development of (1) a research platform that could benefit the acoustic telemetry community throughcapacity building, (2) a centralized database, and (3) key deployment sites and studies on priority species requiringresearch in Europe. A network may increase efficiency, expand the scope of research that can be undertaken, promoteEuropean science integration, enhance the opportunities and success of acquiring research funding and, ultimately,foster regional and transatlantic collaborations. It may also help address research priorities such as the large-scalesocietal challenges arising from climate change impacts and assist the EU’s Marine Strategy Framework Directive viaidentification of good environmental status of endangered or commercially important species.

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  • 4.
    Addo, Louis
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Hajiesmaeili, Mahboobeh
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Piccolo, John
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Watz, Johan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Growth and mortality of sympatric Atlantic salmon and brown trout fry in fluctuating and stable flows2023In: Ecology of Freshwater Fish, ISSN 0906-6691, E-ISSN 1600-0633, no 2, p. 282-290Article in journal (Refereed)
    Abstract [en]

    Sub-daily fluctuations in streamflow may have adverse effects on the biota downstream of dams in hydropeaking-regulated rivers. Although the stranding of salmonid fry is one documented effect of hydropeaking, little is known about the species-specific behavioural and subsequent growth effects of sub-daily flow fluctuations. We investigated the effects of sub-daily flow fluctuation on growth, mortality and behaviour of sympatric Atlantic salmon (Salmo salar) and brown trout (S. trutta) fry (29–34 mm) in a laboratory experiment. The fluctuating flow treatment negatively affected growth and increased mortality for trout but not for salmon. The level of aggressive behaviour was similar in the fluctuating- and stable-flow treatments. Within the fluctuating flow treatment, there was a trend that more fishes were visibly active above the substrate during low than high flow. These findings suggest that hydropeaking-induced flow fluctuations may affect fry of different salmonid species in different ways and that brown trout fry may be more vulnerable to hydropeaking effects than Atlantic salmon fry. It can therefore be important to consider the possibility of divergent reactions by different fish species under hydropeaking situations and to incorporate species-specific strategies to conserve culturally and economically relevant riverine fish species.

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  • 5.
    Adolfsson, Oscar
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Effekter av inkuberingstemperatur hos juvenil atlantlax (Salmo salar L.)2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Rising temperatures, because of climate change, will have major consequences for the world's fish populations, including the Atlantic salmon Salmo salar L. The greatest temperature changes are expected to occur during winter, which will affect S. salar since the eggs are developing during this time of year. Several studies have shown that elevated temperatures during embryogenesis cause morphological changes, in S. Salar, that are shown in later life stages. Some of these studies indicate that eggs incubated at high temperatures should generate parr with deeper bodies. To investigate whether high temperatures during the egg stage cause changes in body shape, parr from normal and high temperature incubated eggs, referred to as as “cold” and “warm” fish, respectively, were examined. A box-truss of euclidean distances between 10 landmarks on the fish body and a discriminant function analysis (DFA) was used to determine which of the distances best discriminated between the two groups. The test showed a significant discrimination between cold and warm parr regarding body shape where cold parr had greater heads and warm parr were deeper over the tail region and showed greater distances between the pelvic fin and the front attachment of the anal fin. 67,3 % of all parr where correctly classified by the test. These results support those notions that indicates that the incubation temperature is important for the morphological development of S. salar although it does not support the hypothesis.

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  • 6.
    Affonso, Igor de Paiva
    et al.
    Universidade Estadual de Maringá, Maringá, Brazil; Universidade Tecnológica Federal do Paraná, Campus Ponta Grossa, Brazil.
    Karling, Leticia Cucolo
    Universidade Estadual de Maringá, Maringá, Brazil.
    Takemoto, Ricardo Massato
    Núcleo de Pesquisas em Limnologia Ictiologia e Aqüicultura – Nupélia, Maringá, Brazil.
    Gomes, Luiz Carlos
    Universidade Estadual de Maringá, Maringá, Brazil; Núcleo de Pesquisas em Limnologia Ictiologia e Aqüicultura – Nupélia, Maringá, Brazil.
    Nilsson, Per Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). Department of Biology, Lund University, Lund, Sweden.
    Light-induced eye-fluke behavior enhances parasite life cycle2017In: Frontiers in Ecology and the Environment, ISSN 1540-9295, E-ISSN 1540-9309, Vol. 15, no 6, p. 340-341Article in journal (Refereed)
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  • 7.
    Agestam, Elin
    Karlstad University.
    Spridning av contorta från bestånd i södra Sverige: En fältstudie i Östergötland och Småland2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Contorta (Pinus contorta) is a coniferous tree species from western North America that has been introduced mainly in northern Sweden. The purpose of this work was to evaluate how far and to what extent (number of self-dispersal seedlings/ha) Contorta has spread from older populations in southern Sweden. The result can be used in assessing the risk of spreading in southern Sweden. The three forest stands used for this work were located in southern Östergötland and northern Småland, Sweden. The data collection was done in three stages in each stand: 1. Assessment if contorta can be disseminated and established from stocks in southern Sweden. 2. Subjective inventory of Contorta plants in selected areas. 3. Quantitative inventory of contorta plants along defined corridors, 2 meters wide and 250 meters long, in four directions from the edge of the stock. In the inventory of subjectively selected areas, contorta plants were found 350 meters from a contorta stand and in the objective inventory 50 meters from a contorta stand. A total of 27 contorta plants (equivalent to 450 plants/ha) was found in subjectively inventory and 18 contorta plants (45 plants/ha) were found in the quantitative inventory. All Contorta seedlings were found on disturbed ground and where the canopy cover of trees was zero, i.e. where the access to light was highest. On the other hand, based on this study, it is not possible to say which factor is most important for the establishment, field disturbance or light supply.

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  • 8.
    Ahlgren, Caroline
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Har signalarter störst förekomst inom eller utanför Dalarnas boreala naturreservat?: En studie om arttätheten av signalarter i Dalarnas barrskogar2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today, it is well known that biological diversity is decreasing worldwide, and the presence of indicator species can identify areas with high biological diversity. Environments with a high presence of indicator species are important to protect and preserve in the form of, for example, nature reserves as these environments indicate high nature values. The aim of this study is to find out whether the coniferous forest's indicator species have the greatest species density and occurrence within the boundaries of the nature reserves in Dalarna, Sweden. The distribution of 10 different indicator species within the coniferous forests of Dalarna, Sweden, was mapped in the QGIS software and the total species density inside as well as outside the nature reserves of Dalarna was compared in the statistical program SPSS. The species density of five selected indicator species was compared inside versus outside of the reserves. The result for the 10 indicator species showed that there was no significant difference between inside versus outside of the reserves, although there were a higher species density per hectare outside the boundaries of the nature reserves. The result for the five selected indicator species showed no significant difference between inside versus outside of the reserves, however, the species density of both R.subpinnatus and P.grossa were higher within the boundaries of the nature reserve. More sightings of indicator species outside the boundaries of nature reserves may indicate that the public is more inclined to report sightings in unprotected areas, rather than reporting sightings in protected areas that have already been established as having high nature values. Many species observations are found just outside the boundaries of the nature reserve, which may indicate that high nature values occur there as well. Further studies about potential buffer zones and their impact on indicator species are encouraged.

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  • 9.
    Ahlgren, Johan
    et al.
    Lund Univ, Dept Biol Aquat Ecol, S-22362 Lund, Sweden..
    Chapman, Ben B.
    Lund Univ, Dept Biol Aquat Ecol, S-22362 Lund, Sweden.;Univ Nottingham, Sch Life Sci, Nottingham NG7 2RD, England..
    Nilsson, Anders P.
    Bronmark, Christer
    Lund Univ, Dept Biol Aquat Ecol, S-22362 Lund, Sweden..
    Individual boldness is linked to protective shell shape in aquatic snails2015In: Biology Letters, ISSN 1744-9561, E-ISSN 1744-957X, Vol. 11, no 4, article id UNSP 20150029Article in journal (Refereed)
    Abstract [en]

    The existence of consistent individual differences in behaviour ('animal personality') has been well documented in recent years. However, how such individual variation in behaviour is maintained over evolutionary time is an ongoing conundrum. A well-studied axis of animal personality is individual variation along a bold-shy continuum, where individuals differ consistently in their propensity to take risks. A predation-risk cost to boldness is often assumed, but also that the reproductive benefits associated with boldness lead to equivalent fitness outcomes between bold and shy individuals over a lifetime. However, an alternative or complementary explanation may be that bold individuals phenotypically compensate for their risky lifestyle to reduce predation costs, for instance by investing in more pronounced morphological defences. Here, we investigate the 'phenotypic compensation' hypothesis, i.e. that bold individuals exhibit more pronounced anti-predator defences than shy individuals, by relating shell shape in the aquatic snail Radix balthica to an index of individual boldness. Our analyses find a strong relationship between risk-taking propensity and shell shape in this species, with bolder individuals exhibiting a more defended shell shape than shy individuals. We suggest that this supports the 'phenotypic compensation' hypothesis and sheds light on a previously poorly studied mechanism to promote the maintenance of personality variation among animals.

  • 10.
    Ahlin, Julia
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies (from 2013).
    Handhygien i förskolan: Pedagoger och barns uppfattningar av handhygien och dess roll i förskolan2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study is about preschool teachers and children perceptions about hand hygiene in preschool. It also focusses on preschool teachers’ way of working when it comes to hand hygiene against children. The purpose with this study was to illuminate preschool teachers’ attitudes and working methods with hand hygiene in the preschool and how children reason about hand hygiene. Seven preschool teachers and twelve children from two different preschool participated in the study. The children were interviewed in pairs and the preschool teachers were interviewed individually. It can be read in the results that the preschool teachers think that the children know why they wash their hands and the children agree about that. All seven preschool teachers also indicate that they talk with children about hand hygiene and why it is important. The children do not think that the preschool teachers talk to them about hand hygiene. However, the children do show knowledge about why they should wash their hands and also explains what would happen if they did not do it. Maybe the preschool teachers and the children have different point of view of what ”talking” is in this context when their answers doesn’t match. The preschool teachers and children have a similar perception when it comes to what hand hygiene routines they have and what they use when they wash their hands.

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  • 11.
    Al- Robeyi, Zainab
    Karlstad University, Faculty of Social and Life Sciences.
    Att uppleva naturen med alla sina sinnen: Hur undersöker och upplever förskolebarnen naturen?2013Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    This project discusses various aspects of children's way to explore nature with their senses. Therefore I conducted a study in two preschools, one nature-oriented and another preschool. This study was carriedout usien the three metods, interviews, observations and surveys. Interview four children from each preschool, observations of each group outdoors during four different occasions and question forms to teachers.

     

    The result of the study showed that both teachers and children have a great interest in being outdoors in nature, but it is not always possible to take out all children's groups. The reason is large groups and inadequate staff. When you are out in the forest according to teachers, it is important to be attentive, present, and meet the children’s interests. They need to be stimulated with questions and inspire them about what is happening and what might happen in nature plus take natural materials as help in the creative activities of the preschool.

     

    Keywords: Biology, children's perceptions, exploring, outdoor environment

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  • 12.
    Alam, Kiran
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Engineering and Chemical Sciences (from 2013).
    Disrupting protein folding in Disulfide Oxidoreductase A, DsbA -proteins: Breaking disulfide bonds in DsbA proteins from Gram Negative bacteria a Computational study in YASARA2024Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The worldwide problem of antibiotic resistance is most challenging when dealing with Gram – negative bacteria, largely due to the presence of a protein known as DsbA, which forms disulfide bonds. In this study, we utilized a software named YASARA Structure to select 12 DsbA proteins from various Gram – negative bacteria, including two from E. coli, one of which was a mutated variant. The study was conducted in two parts. The first involved using cleaved peptides from each protein as a ligand. The second part involved using 60 ligands from various studies for protein – ligand docking. It was found that protein 3F4R and 5KBC demonstrated superior docking in terms of protein – ligand docking. These proteins showed lower binding energy when the peptide bound to the entire active site, and strong hydrophobic interactions between the protein’s active sites and 40 and 20 ligands respectively. In terms of protein – peptide docking, proteins 3L9S and 7LUH exhibited the highest binding energy, 7.76 and 7.66 kcal/mol, respectively, around the active sites. A superimposition was preformed using 1DSB as a reference, revealing that all these proteins had similar structural shapes as the RMSD values were below 3 Å and had a residue sequence identity ranging from 16.09 to 99.47%. This study is computational in nature and explores theoretical aspects that may not directly correlate with experimental findings. 

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  • 13.
    Almgren Damberg, Ingrid
    Karlstad University, Faculty of Arts and Social Sciences (starting 2013), Department of Educational Studies.
    "Nyss så träffa jag en krokodil, som körde runt i en bil": Små barns kompetenser i ämnet biologi2015Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of the study is to show young children's competences in the subject of biology. I hope that my work will lead to that the subject of biology is used more often in the preschool context. In my work I have had an intra-active theory as a base. I have searched for what children are interested in on the subject of biology. Here, I can conclude that animals and plants are major interests for the children. Furthermore, I wanted to explore the ways in which children's knowledge became visible. For the most part, small children (along with educators) use animism and anthropomorphism, however, this is often interwoven with facts. I also wanted to know whether there were factors that contributed to children's learning in biology. It became clear that factors such as outdoor stay and live animals and plants contributed to a fact-based learning in biology. In contrast, factors such as indoor stay and toys were important factors for an animistic and anthropomorphic learning in biology. Educators also have a crucial role in children's learning in biology. Through an intra-active approach, I note that both the factual events of biology and animism and anthropomorphism contribute to the child's creation of knowledge in biology.

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  • 14.
    Alvsenius Fransson, Åse
    Karlstad University.
    Behövs det speciella anordningar för att bedriva utomhuspedagogik?2008Independent thesis Basic level (professional degree), 10 points / 15 hpStudent thesis
    Abstract [sv]

    I mitt arbete har jag genom observationer och intervjuer undersökt om skolskogen och den vanliga skogen är bra komplement när det handlar om utomhuspedagik. De flesta av förskolorna i kommunen har en skolskog att tillgå och har man inte det växer skogen nästan inpå knutarna. De pedagoger som blivit intervjuade anser att det är viktigt att lära barnen tidigtvad man får och inte får göra i naturen och att skolskogen då är ett bättre alternativ. En skolskog skiljer sig från en vanlig skog genom att det finns färdiga vindskydd, eldstäder och hinderbanor. Genom avtal med markägaren har förskolan eller skolan fått tillstånd att tänja lite på allemansrättens gränser Dessutom är det bra för både barn och pedagoger att spendera mycket tid ute i naturen därför att den friska luften gör att det blir färre sjukdomar. I läroplanen står det att förskolan skall lägga stor vikt på natur och miljö, samt att vi ska värna om barnens hälsa. Den litteratur jag använt mig av i arbetet handlar om hur viktigt det är att arbeta med utomhuspedagogik i förskolan och att skolskogen och skogen är mycket bra att vistas i. Litteraturen tar även upp hur viktigt det är att pedagogen har bra kunskap om naturen för att vistelsen ska bli så bra och lärorik som möjligt för barnen.

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  • 15.
    Andersson, Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences.
    Catch and effort from a recreational trolling fishery in a large lake2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Over recent decades recreational fisheries have grown substantially throughout the world. Despite this increase, catches from recreational fisheries have often been ignored in fisheries management, although this is now being remedied. Monitoring recreational fisheries can be expensive, and the primary means used for monitoring is angler (creel) surveys, typically funded from sales of fishing licences. The studies presented in this thesis examine different approaches to monitoring recreational trolling fisheries’ catch and effort, where fishing licenses are not required and there are no reporting requirements. I present results from a complemented roving/mail-in survey undertaken during 2013-2014 to estimate recreational effort and catch of Atlantic salmon (Salmo salar) and brown trout (S. trutta) in the largest lake in the European Union, Lake Vänern, Sweden. I also evaluate different angler catch reporting methods (mail-in, tournament reports and face-to-face interviews) and compare catch rates within and among spring and fall fishing periods. In addition, mail-in survey data are examined for recall bias.

     

    I estimate that 28.7 tonnes of salmon and trout combined were harvested by the recreational trolling fishery in 2014, more than the commercial and subsistence fisheries combined. Seasonal differences in both recreational effort and catch were observed. Effort, in boat hours, was significantly higher in spring than in fall. Catch rates of trout were higher in fall than in spring, but there were no seasonal differences in catches of salmon. Harvest per boat day did not differ significantly among catch reporting methods, indicating that all three methods could be useful for managers interested in harvest rates. In contrast, total and released catch per boat day differed among reporting methods, with tournament anglers catching more fish in total. Finally, there was little evidence for recall bias in mail-in surveys, indicating that mail-in surveys are useful for collecting unbiased catch data. My study is the most comprehensive angler survey to date for Lake Vänern, and my results should be of immediate use to local fisheries managers and should also be of interest to researchers and managers interested in estimating catch and effort for fisheries at large spatial scales.

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  • 16.
    Andersson, Anders
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Bergman, Eva
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Greenberg, Larry
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Piccolo, John
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Comparing mail-in, interview and tournament catch rates for a recreational salmonid fisheryManuscript (preprint) (Other academic)
  • 17.
    Andersson, Anders
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Greenberg, Larry
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Bergman, Eva
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Su, Z.
    Michigan Department of Natural Resources and University of Michigan.
    Andersson, M
    Swedish University of Agricultural Sciences.
    Piccolo, John
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Recreational trolling effort and catch of Atlantic salmon and brown trout in Vänern, the EU's largest lake2020In: Fisheries Research, ISSN 0165-7836, E-ISSN 1872-6763, Vol. 227, article id 105548Article in journal (Refereed)
    Abstract [en]

    Recreational fishing has grown substantially worldwide; for some recreational fisheries both catch and economic value now exceeds that of commercial fisheries. Monitoring of recreational fisheries effort and catch is therefore important for sustainable fisheries management. We developed and implemented an angler survey to estimate effort and catch for the recreational trolling fishery for landlocked Atlantic salmon (Salmo salar) and brown trout (S. trutta) in Lake Vänern, Sweden. Major challenges were the large spatial scale and dispersed fishing effort, a lack of revenue from fishing licence sales, and a lack of catch reporting requirements. We developed a complemented roving/mail-in survey to estimate effort and catch during the main fishing periods, spring and fall, 2014. Instantaneous counts from major access sites were used for effort estimates, and mail-in surveys were used for catch rates. Our results show that Vänern supports a salmon and trout fishery of some 28.7 ± 3.3 tonnes per year. Fishing effort was higher in the spring than in the fall, and there were seasonal differences in catch rates for trout but not for salmon. Estimates show that the recreational trolling fishery now harvests more salmon and trout annually than do the commercial and subsistence fisheries combined. This highlights the importance of continuing an angler survey program for Vänern as a key element for sustainable fisheries management, and can serve as a model for other recreational fisheries at large spatial scales.

  • 18.
    Andersson, Anders
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Greenberg, Larry
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Bergman, Eva
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Su, Zhenming
    Andersson, Magnus
    Piccolo, John
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Estimating effort and catch of a recreational trolling fishery in one of Europe’s largest lakesManuscript (preprint) (Other academic)
  • 19. Andersson, Erika
    Barns möjligheter till lärande om och med kroppen genom fysisk rörelse: En kvalitativ intervjustudie om förskollärares arbetssätt2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Biologi är ett stort ämne i naturvetenskap där läran om människokroppen inkluderas. Men på vilket sätt får barnen i förskolan lära sig om människokroppen? En viktig kompetens att få vetskap om i förskolan är människokroppens funktion för att må bra som människa. Syftet med studien är att belysa förskollärares erfarenheter av och syn på att främja barns lärande om och med kroppen genom fysisk rörelse. Metoden som använts är semistrukturerade intervjuer där sex förskollärare deltog från en kommun i Mellansverige. Resultatet i studien visar att förskollärare arbetar med människokroppen i olika aktiviteter med barnen genom deras intresse och frågor. Att redogöra för hur kroppen fungerar i olika aktiviteter är svårt anser förskollärarna. De arbetar för att synliggöra glädjen som den fysiska rörelsen medför. Utifrån studiens resultat och slutsatser framkommer det att förskollärarna anser vad betydelsefullt arbete med människokroppen är då den finns med oss hela livet. Förskollärarna anser även att genom rörelse får barnen utforska omvärlden där de berikas med nya erfarenheter. Implikationer för verksamheten blir att redan i förskolan berika barnen med kunskap om vad som behövs för att gynna människans mående. Arbetet handlar om att hitta rörelseglädje, bevara nyfikenheten och skapa förutsättningar för alla barn att kunna ta del av upplevelser genom utforskandet tillsammans.

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  • 20.
    Andersson, Fredrika
    Karlstad University, Faculty of Social and Life Sciences.
    Barns tankar om den egna kroppen!: Vad vet fyraåringar och sexåringar om sin kropp!2009Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this research was to investigate the concepts among five and six year old children regarding the human body. Six children were interviewed by means of qualitative interviews. The children's concept regarding the human body differed depending on their age. The six year old children knew more about the body than the four year old children. Spontaneously the children knew we had heart, brain, blood, brain cells, muscles and skeleton

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  • 21.
    Andersson, Frida
    Karlstad University, Faculty of Social and Life Sciences.
    Vikten av utevistelse inom förskolan: En studie av pedagogers tankar och syften med utevistelse2008Independent thesis Basic level (degree of Bachelor), 10 points / 15 hpStudent thesis
    Abstract [sv]

    I min undersökning har fem pedagoger genom strukturerade intervjuer fått svara på frågor om utevistelsen på förskolan. Syftet var att ta reda på vad pedagogerna själva hade för tankar och syften bakom utevistelsen, samt hur de arbetade med detta. Frågorna gällde både vistelsen i den planerade miljön på gården och i naturen.

    Pedagogerna fann mestadels fördelar med utevistelse på förskolan. Några av fördelarna som nämndes var god motorikträning och social träning. Sedan belystes även vikten av ”frisk luft” och att pedagogerna upplevde barnen som piggare om de vistades utomhus emellanåt.

    Minst en gång om dagen går de ut med barnen på gården och de flesta försöker komma iväg till skogen en gång i veckan. En nackdel kan vara avbrott under leken inomhus för att man ska gå ut.

    Pedagogerna framhåller i sina syften att de vill förmedla kunskap om naturen på ett lekfullt sätt för att stimulera barnens nyfikenhet genom utevistelsen.

    Nyckelord: Lekfullt, nyfikenhet, pedagogers syften, utevistelse

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  • 22.
    Andersson, Jan-Olov
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    A GIS-based landscape analysis of dissolved organic carbon in boreal headwater streams2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In boreal catchments, stream water chemistry is influenced and controlled by several landscape factors. The influence of spatially distributed variables is in turn dependent on the hydrological scale. Headwater streams have larger variability of water chemistry, and thus together represent a large biodiversity, and therefore need to be monitored in official environmental assessments. One objective of this study was, using Geographical Information Systems (GIS), to analyse co-variation between landscape variables and water chemistry and to determine which of the landscape variables have a major influence on the concentration of dissolved organic carbon (DOC) in headwater streams. Another objective was to find a simple method for predicting sources of DOC, using official map data and publically available GIS applications.

    Totally 85 headwater catchments (0.1-4 km2) in the county of Värmland, western south Sweden, were used in the study. Water chemistry was analysed for water sampled at low, medium and high flows, and landscape variables were extracted from official map data sources: topographic maps, a digital elevation model (DEM, 50 m grid), and vegetation data. Statistical analyses showed that topography (mean slope and mean topographic wetness index (TWI)) and wetland cover often correlated well with DOC in headwater catchments. Official map data could satisfactorily extract landscape variables (mean slope, mean TWI) that were useful in predicting stream water chemistry (DOC).

    A high-resolution elevation model, which was generated by interpolation of photogrammetric data, was used to calculate and evaluate two different wetness indices and their ability to predict the occurrence of wetlands in six catchments of different sizes and topography. The SAGA (System for Automated Geoscientific Analyses) wetness index (SWI) gave substantially better results than the TWI. The effects of resolution of DEMs on calculations of the SWI were investigated using 5, 10, 25 and 50 m grids. The results showed that SWI values increased with increasing cell size. The near linear increment of mean values for resolutions 10-50 m suggests a independence of terrain type and catchment size, which supported previous findings that indicated that mean slope and mean wetness index calculated from coarse elevation models may be used for prediction of DOC in headwater streams.

     

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  • 23.
    Andersson, Jan-Olov
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    DEM resolution effects on SAGA wetness index in boreal forested catchmentsManuscript (preprint) (Other academic)
  • 24.
    Andersson, Jan-Olov
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Nyberg, Lars
    Karlstad University, Faculty of Social and Life Sciences, Centre for Climate and Safety.
    Spatial variation of wetlands and flux of dissolved organic carbon in boreal headwater streams2008In: Hydrological Processes, ISSN 0885-6087, E-ISSN 1099-1085, no 22, p. 1965-1975Article in journal (Refereed)
    Abstract [en]

    In order to investigate the relation between water chemistry and functional landscape elements, spatial data sets of characteristics for 68 small (0·2–1·5 km2) boreal forest catchments in western central Sweden were analysed in a geographical information system (GIS). The geographic data used were extracted from official topographic maps. Water sampled four times at different flow situations was analysed chemically. This paper focuses on one phenomenon that has an important influence on headwater quality in boreal, coniferous forest streams: generation and export of dissolved organic carbon (DOC). It is known that wetland cover (bogs and fens) in the catchment is a major source of DOC. In this study, a comparison was made between a large number of headwater catchments with varying spatial locations and areas of wetlands. How this variation, together with a number of other spatial variables, influences the DOC flux in the streamwater was analysed by statistical methods. There were significant, but not strong, correlations between the total percentages of wetland area and DOC flux measured at a medium flow situation, but not at high flow. Neither were there any significant correlations between the percentage of wetland area connected to streams, nor the percentage of wetland area within a zone 50 m from the stream and the DOC flux. There were, however, correlations between catchment mean slope and the DOC flux in all but one flow situations. This study showed that, considering geographical data retrieved from official sources, the topography of a catchment better explains the variation in DOC flux than the percentage and locations of distinct wetland areas. This emphasizes the need for high-resolution elevation models accurate enough to reveal the sources of DOC found in headwater streams.

  • 25.
    Andersson, Jan-Olov
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Nyberg, Lars
    Karlstad University, Faculty of Social and Life Sciences, Centre for Climate and Safety.
    Using official map data on topography, wetlands and vegetation cover for prediction of stream water chemistry in boreal headwater catchments2009In: Hydrology and Earth System Sciences, ISSN 1027-5606, E-ISSN 1607-7938, Vol. 13, p. 537-549Article in journal (Refereed)
  • 26.
    Andersson, Jan-Olov
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Nyberg, Lars
    Karlstad University, Faculty of Social and Life Sciences, Centre for Climate and Safety.
    Wetness indices as predictors of boreal wetlandsManuscript (preprint) (Other academic)
  • 27.
    Andersson, Jeanette
    Karlstad University.
    Påverkan av jakttryck, habitatförlust och populationsstorlek på jaguar (Panthera onca) i Tapajós - Arapiuns Extractive Reservat i centrala Amazonas2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The jaguar is endangered due to hunting and deforestation of rainforests, which in turn reduces the jaguar’s prey. This report is based on a population in the Tapajós - Arapiuns Extractive Reserve in central Amazonia and how hunting pressure, the distribution of sexes killed by hunting, the loss of habitat and population size affect the population during the next 100 years. With the help of previous studies on the hunting pressure and information about jaguar biology in the Tapajos, different simulation models were conducted to gain an appreciation of how the jaguar was affected. A total of thirteen scenarios was made. In the scenarios without hunting and habitat loss, which is not very likely to occur.

    I found that the jaguar has good chances of survival after 100 years. Scenarios with low hunting pressure, with the removal of 3 females and 9 males per year indicated that the population declined but still had a good chance of survival. Survival was less likely when hunting pressure increased to 5 females and 14 males. If habitat loss was added to the high hunting pressure, the jaguars went extinct even faster. Scenarios with a habitat loss of 0.24% or 0.71% represented a low risk of extinction in 100 years, but if hunting was added, the risk of extinction increased dramatically. In scenarios with a smaller population size, with different hunting pressure and habitat loss, the populations were very sensitive to change. In the worst case scenario, with hunting higher on females than males, there were serious negative impacts on the population, which is likely to go extinct very quickly.

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  • 28.
    Andersson, Jessica
    Karlstad University, Faculty of Social and Life Sciences.
    Barns beteenden i naturen2007Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    This study is based on qualitative interviews with five-year-old children from a nursery school and two teachers with great experience. The purpose with the interviews is to find out what knowledge these children have about the Right of Common and what the teachers think they need to find this knowledge.

    The children didn't know what the word Right of Common stands for but when they got more concrete alternatives they had good experiences. The two teachers had different opinions about what is the most important concerning the stays in the nature. Exercise meant a lot for one teacher. To have fun and to use all your senses were more important for the other one. To give the wooded strolls new permanent experiences it is recommended to use your imagination.

    Key words: The Right of Common, science, process of learning

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  • 29.
    Andersson, Lena
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Flodpärlmusslans (Margaritifera margaritifera) påverkan på öringens (Salmo trutta) tillväxt, konditionsfaktor och habitatval.2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The freshwater mussel family Unionoida lives a complex life with its host animals and the freshwater mussel family’s existence is threatened worldwide. One of these species, the pearl mussel (Margaritifera margaritifera), is a “responsibility species” for Scandinavia and a lot of work is ongoing to save the species. In Scandinavia there are still existing populations, but in many waters recruitment of juvenile mussels is completely lacking or insufficient. To support recruitment and also reintroduce the mussel into suitable watercourses, more knowledge about its complex life cycle and how it affects its host brown trout (Salmo trutta), is required. Attempts have been made to introduce gravid mussels or already infected trout in order to try to rejuvenate or to reintroduce mussels in some rivers. In this study, 293 trout individuals were captured from three watercourses in western Sweden with no or inadequate recruitment of juvenile pearl mussels. The brown trout were treated with mussel infection by being kept in containers with the presence of gravid mussels and compared to a control group where no mussels were present. Growth, condition factor and habitat selection were investigated and checked after treatment by scanning the trout with a mobile scanner and recaptured for control. The analyzes showed a significantly lower growth on those trout treated with mussel infection during the time they were stored in the containers. After a month in freedom in the streams, there was no differences in growth or condition factor. Habitat choice studies showed that trout with a higher degree of infection chose calmer water with a bottom layer of finer sediment. The study showed that this method could be a simple way of increasing the reproduction success of pearl mussel. The method requires relatively little work effort and small disturbance to host fish or the aquatic environment.

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  • 30. Andersson, Lena U
    Betydelsen av bark pH på lövträd för fyra epifytiska mossor.2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Several species of  epiphytic bryophytes in Sweden are endangered because of habitat loss, which in turn is caused by intensified forestry and changes in the cultural landscape. Several species of common deciduous trees have also been threatened by diseases, which has reduced their numbers. A couple of our environmental goals in Sweden address forestry and the conservation of biodiversity. Since it is known that the red listed species are more common on trees with a higher bark pH  I have chosen to compare four common mosses; two that are common in special environments such as tree-lined avenues and parks and two that are common on most trees in western Sweden. This study investigated the difference of bark pH for Leucodon sciuroides, Homalothecium sericeum, Hypnum cupressiforme and Ulota crispa on different host tree species in three different study areas. The hypothesis was that preferences for bark pH differ significantly between the different mosses. It was found that Leucodon sciuroides and  Homalothecium sericeum  were more common on trees with a higher bark pH while Hypnum cupressiforme and Ulota crispa grew on tree bark with a lower pH. Furthermore it was found that both Hypnum cupressiforme and Ulota crispa could also be found on tree bark with a higher pH. There was also a difference in terms of tree species. The avenue trees had the most species, especially the ash tree.

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    Betydelsen av bark pH på lövträd för fyra epifytiska mossor.
  • 31.
    Andersson, Madelen
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Epifytiska lavar som indikatorer på luftföroreningar: en jämförelse mellan stad och landsbygd inom Karlstads kommun2020Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Air pollution has been a significant problem for humans and nature. The fact that lichens are negatively affected by air pollution has been known for a long time. The sensitivity of lichens to air pollution is species-specific, which means that lichen can be used as indicators of air quality. The purpose of this study was to investigate the species composition, frequency and cover of specific epiphytic lichens along a gradient, from city to countryside, to investigate changes with regard to air pollution. The study was conducted within Karlstad municipality where three different area categories, city, outskirts and countryside, were studied and compared. The results showed several significant differences between sensitive and resistant epiphytic lichens as well as the interaction between these groups and the different area categories. Sensitive species were found in higher numbers and frequency in the countryside then in the city and its outskirts. The cover of sensitive species increased from the city to the countryside, but resistant species had a significantly higher coverage ratio in all area categories. Significant differences in the lichen community between the city and countryside indicate that air quality is improving along the gradient studied. There are many environmental factors that may affect the composition of the lichen community, but despite these trends consistent with presumed differences in air quality were found.

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  • 32.
    Andersson, Madelen
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Naturvårdsbränningens effekter på botten- och fältskiktsvegetation2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Forest fires are an important part of the boreal forest ecosystem but have become very reduced in Sweden over the past 100 years. To recreate this feature in nature, prescribed forest fire has become a management method used to promote biodiversity. The purpose of this study was to investigate the effects of prescribed forest fire on the ground and field layer vegetation in terms of vegetation structure, species composition, coverage ratio, biomass and soil pH. The study was conducted in the Brännan Nature Reserve where prescribed forest fires have been implemented on several occasions during the past 21 years, which also made it possible to compare several areas and investigate effects over time. Four sub-areas were studied, three previously fire-affected areas and one control area. The result shows that prescribed forest fires influence the ground and field layer vegetation, and there were significant differences between the areas. The vegetation structure changed, and new conditions were created for subsequent successional processes. The effective number of species decreased after the fire but subsequently increased over time. The percentage of vegetation cover showed the same result with a rapid re-establishment rate, especially during the 6 following years. Biomass production reached the highest value 21 years after the fire, but showed a declining trend compared to the control area. There was no significant difference regarding soil pH, which was expected. There are many factors that may affect the short- and long-term effects of prescribed forest fires, such as fire intensity and the soil depth reached by the fire, but despite variations among the areas, some trends were found.

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  • 33.
    Andersson, Magdalena
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Utvärdering av rörelsemönster hos öring (Salmo trutta) utifrån otolitmikrokemi2014Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The classic view of trout (Salmo trutta) life history is that trout begins its life in freshwater, migrates to the ocean after about 1-4 years and then returns to freshwater to spawn. As trout fry have been caught at the mouth of the River Emån, near the Baltic Sea, researchers have speculated that some trout emigrate during their first year of life. The purpose of this study was to describe the variation in the length of time trout reside in freshwater before they migrate to the ocean for the first time. Another purpose was to investigate whether it was possible to discern where and how long the fish spent in freshwater and saltwater during different parts of their lives. Between 2007 and 2009, 23 adult trout were captured in the River Emån in southeastern Sweden. From each fish, a microchemical analysis of the sagitta otolith was conducted. The analysis focused on measuring the ratio of strontium:calcium from the center of the otolith to its outer edge at 6μm intervals. Based on this analysis, I found that 26% of the trout in the population emigrated to sea before they had reached the age of one. The largest proportion (48%) of trout emigrated between 1 to 2 years of age. The results of my study indicated that there was a significant correlation between age and the number of times that the fish remained in freshwater. I also analyzed the ratio of zinc:calcium and manganese:calcium. The analysis of zinc showed annual fluctuations, including a high value during the fish's first year and a seasonal pattern, with higher values of Zn:Ca in spring and summer. My results also showed some variation of the trace element manganese, half of the fish showed a peak in their first year. The results of this study indicate that by analyzing the concentrations of trace elements in otoliths one can describe individual variation in brown trout movement patterns and life history.

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  • 34.
    Andersson, Magdalena
    et al.
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Jonsson, Bror
    Karlstad University, Faculty of Health, Science and Technology (starting 2013). Norwegian Institute for Nature Research, Norway.
    Calles, Olle
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Greenberg, Larry
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Assessing Movements between Freshwater and Saltwater by Brown Trout (Salmo trutta L.) Based on Otolith Microchemistry2024In: Animals, E-ISSN 2076-2615, Vol. 14, no 14, article id 2116Article in journal (Refereed)
    Abstract [en]

    By analyzing otolith microchemistry, we examined the use of freshwater and marine environments by brown trout Salmo trutta L. that spawn in the Swedish River Emån and migrate to the Baltic Sea. We estimated the time juveniles spent in freshwater and the number of times the fish returned to freshwater, presumably to spawn. Twenty-six percent of the fish migrated to sea by 1 year of age. However, 13% spent less than one year in the river. Most brown trout (48%) migrated to the sea between 1 and 2 years of age. On average, brown trout, which averaged 4.4 years in age (range 3–6 years), returned to freshwater 2.3 times, and there was an inverse relationship between time spent in freshwater after hatching and the number of visits to freshwater. Our results do not support the classical life history pattern, where brown trout spend one or more years in freshwater before migrating to the sea. Here, we found evidence that part of the population leaves freshwater during their first year. While the cause for precocial migration in the River Emån is not known, our results from this permanently flowing river do not support the idea proposed for other Baltic Sea populations, where the risk of drought has been suggested to be the cause. 

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  • 35.
    Andersson, Maria
    Karlstad University, Faculty of Social and Life Sciences.
    Miljö- och naturarbete i förskolan: en studie om hur pedagoger genomför miljö- och naturarbetet i förskolan2013Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this survey was to investigate and describe how the work with environment and nature work can be implemented in preschool. The survey is based on qualitative semi-structured interviews, with nine educators from five different preschools, in one municipality in west Sweden. The result of the survey shows that there are many different ways to work with environment and nature in preschool, both practical and theoretical. Working with recycling, composting and discuss the conservation of resources were some of the activities that the surveys educators used to do. It was also revealed in the study that there are some obstacles in the environmental and nature work, such as staff shortages and educators interests.

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  • 36.
    Andersson, Matilda L.
    et al.
    Lund University ; Uppsala University.
    Hulthen, Kaj
    Lund University.
    Blake, Charlie
    Lund University ; Webster University, USA.
    Broenmark, Christer
    Lund University.
    Nilsson, Per Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). Lund University.
    Linking behavioural type with cannibalism in Eurasian perch2021In: PLOS ONE, E-ISSN 1932-6203, Vol. 16, no 12, article id e0260938Article in journal (Refereed)
    Abstract [en]

    The propensity to kill and consume conspecifics (cannibalism) varies greatly between and within species, but the underlying mechanisms behind this variation remain poorly understood. A rich literature has documented that consistent behavioural variation is ubiquitous across the animal kingdom. Such inter-individual behavioural differences, sometimes referred to as personality traits, may have far-reaching ecological consequences. However, the link between predator personality traits and the propensity to engage in cannibalistic interactions remains understudied. Here, we first quantified personality in Eurasian perch (Perca fluviatilis), measured as activity (time spent moving) and sociability (time spent near conspecifics). We then gave perch of contrasting behavioural types the option to consume either conspecific or heterospecific (roach, Rutilus rutilus) prey. Individual perch characterized by a social-active behavioural phenotype (n = 5) selected roach before being cannibalistic, while asocial-inactive perch (n = 17) consumed conspecific and heterospecific prey evenly. Thus, asocial-inactive perch expressed significantly higher rates of cannibalism as compared to social-active individuals. Individual variation in cannibalism, linked to behavioural type, adds important mechanistic understanding to complex population and community dynamics, and also provides insight into the diversity and maintenance of animal personality.

  • 37.
    Andersson, Mikael
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Kartläggning av fluviala påverkansfaktorer hos biflödesmynningsområden inom Klarälvens avrinningsområde: Utgör biflödesmynningsområdena hot-spots för fisk?2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Abstract

    Tributary areas and confluence zones play an important role, not least through their ability to change environmental conditions and elicit a biological response in the main stream they flow into. Tributary areas also provide sites of high inherent ecological value, where specific biophysical processes and ecological services are often concentrated. The purpose of this study was to investigate whether tributary mouths within the catchment area of Klarälven constituted hotspots for fish and to identify possible environmental factors associated with hotspots. Parameters studied were species composition and mean density, as well as the physical factors such as average depth, local width, bottom substrate, water level, water velocity and the occurrence of migratory obstacles in the watercourse. Most species were found in the mainstream, whereas tributary mouths had the second highest species richness and upstream tributaries had the lowest number of species. The mean density of the alpine bullhead (Cottus poecilopus), eurasian minnow (Phoxinus phoxinus) and burbot (Lota lota) was greatest in the tributary mouths, while the mean density of salmon (Salmo salar) and trout (Salmo trutta) was greatest upstream of the tributaries. The results also showed that trout, to a greater extent than salmon, occurred higher upstream in the tributaries, a relationship that is also supported by previous studies. Regarding the physical factors, water velocity was significantly higher in the tributary mouths and upstream tributaries than in the mainstream, while the highest diversity for bottom substrate composition was found in the mainstream. Based on these results, it was difficult to conclude whether tributary mouths actually constituted hotspots for fish or not, as it varied depending on the parameters studied. Overall tributary mouths within the catchment area of Klarälven did not constitute hotspots for fish.

    Keywords: Estuary, tributary, mainstream, river, rafting, hydropower

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  • 38.
    Andersson, Sandra
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    The effects of artificial illumination on invertebrate drift2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 39.
    Andersson, Örjan
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Hur personlighetstyperna modig eller skygg hos oval dammsnäcka (Radix balthica) påverkas av närvaro eller frånvaro av prederande fisk2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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    fulltext
  • 40.
    Ansmark, Julia
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Utomhusundervisning och elevers relation till naturen: En intervjustudie med lärare kring deras utomhusundervisning2020Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In today’s digitalised society we spend a lot of time indoors, kids included, and not as much time outdoors in nature. Thoughts that might appear because of this include what children’s relation to nature looks like and what we as teachers can do to improve this relation. The purpose of this study is therefore to contribute with knowledge about teachers’ thoughts and use of outdoor education, and how they view pupils’ relation to nature based on their outdoor education.

    The method used in this study was to conduct interviews with five different teachers about their work with outdoor education, along with their thoughts and views on it. A thematic analysis was used to extract different themes from the teachers’ interview answers. This analysis resulted in six different themes covering teachers’ thoughts and outdoor education. The results show that outdoor education often consists of group-based activities with a focus on practical work where many senses are activated and stimulated. According to the teachers, the way that they work with outdoor education also contributes to a more positive relation between pupils and nature, by improving their interest, but also by giving a better understanding of the interaction between humans, animals and plants, as well as our connection to them. Based on these findings, it is important that teachers try to use more of this kind of outdoor education to help develop and improve the pupils’ relation to nature, while ensuring a productive and healthy environment.

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  • 41.
    Ardren, W. R.
    et al.
    US Fish & Wildlife Service, USA.
    Greenberg, Larry
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Introduction to “conservation, ecology, and evolution of nonanadromous atlantic salmon”2021In: Canadian Journal of Fisheries and Aquatic Sciences, ISSN 0706-652X, E-ISSN 1205-7533, Vol. 78, no 6, p. iii-ViiArticle in journal (Refereed)
  • 42. Armstrong, Janet L.
    et al.
    Myers, Katherine W.
    Beauchamp, David A.
    Davis, Nancy D.
    Walker, Robert V.
    Boldt, Jennifer L.
    Piccolo, John
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Haldorson, Lewis J.
    Moss, Jamal H.
    Interannual and Spatial Feeding Patterns of Hatchery and Wild Juvenile Pink Salmon in the Gulf of Alaska in Years of Low and High Survival2008In: Transactions of the American Fisheries Society 2008; 137: 1299-1316Article in journal (Refereed)
    Abstract [en]

    To improve understanding of the mechanisms affecting growth and survival, we evaluated the summer diets and feeding patterns (prey composition, energy density, and stomach fullness) of hatchery and wild juvenile pink salmon Oncorhynchus gorbuscha in Prince William Sound (PWS) and the northern coastal Gulf of Alaska (CGOA). Our study (19992004) included 2 years of low (3%), mid (5%), and high (89%) survival of PWS hatchery pink salmon. Because variations in diet should affect growth and ultimately survival, we expected that the variations in diet, growth, and survival would be correlated. During August in the CGOA, pteropod-dominated diets and higher gut fullness corresponded to high survival (59%), and copepod-dominated diets and lower gut fullness corresponded to low survival (3%). Within years, no significant differences were found in diet composition or gut fullness between hatchery and wild fish or among the four PWS hatchery stocks. Diets varied by water mass (habitat) as juveniles moved from PWS to more saline habitats in the CGOA. In July, when juveniles were most abundant in PWS, their diets were dominated by pteropods and hyperiid amphipods. The diets of fish that moved to inner-shelf (i.e., the least-saline) habitat in the CGOA in July were dominated by larvaceans in low-survival years and pteropods in high-survival years. Diet quality was higher in CGOA habitats than in PWS in July. In August, fish moved to the more productive, more saline water masses in the CGOA, where large copepods and pteropods were dominant prey and diet quality was better than in PWS. Our results indicate that spatial variation in the diets of juvenile pink salmon in July and the timing of migration to the CGOA play a critical role in marine growth and survival

  • 43.
    Arnott, Shelley E.
    et al.
    Queen's University, Canada.
    Fugere, Vincent
    Group de Research Interuniversitaire en Limnologie (GRIL), Canada; Université du Québec à Trois-Rivières, Canada.
    Symons, Celia C.
    University of California, USA.
    Melles, Stephanie J.
    Toronto Metropolitan University, Canada.
    Beisner, Beatrix E.
    Group de Research Interuniversitaire en Limnologie (GRIL), Canada; Université du Québec à Montréal, Canada.
    Canedo-Arguelles, Miguel
    Universitat de Barcelona, Spain.
    Hebert, Marie-Pier
    Group de Research Interuniversitaire en Limnologie (GRIL), Canada; Université du Québec à Montréal, Canada; McGill University, Canada..
    Brentrup, Jennifer A.
    Dartmouth College, USA.
    Downing, Amy L.
    Ohio Wesleyan University, USA.
    Gray, Derek K.
    Wilfrid Laurier University, Canada.
    Greco, Danielle
    Queen's University, Canada.
    Hintz, William D.
    The University of Toledo, USA.
    McClymont, Alexandra
    Queen's University, Canada.
    Relyea, Rick A.
    Rensselaer Polytech Inst, USA.
    Rusak, James A.
    Queen's University, Canada; Ontario Ontario Ministry of the Environment, Conservation and Parks, Canada.
    Searle, Catherine L.
    Purdue University, USA.
    Astorg, Louis
    Group de Research Interuniversitaire en Limnologie (GRIL), Canada; Université du Québec à Montréal, Canada.
    Baker, Henry K.
    University of California San Diego, USA.
    Ersoy, Zeynep
    Universidade de Évora, Portugal.
    Espinosa, Carmen
    University of Vic–Central-University of Catalonia (Uvic–UCC), Spain.
    Franceschini, Jaclyn M.
    Wilfrid Laurier University, Canada.
    Giorgio, Angelina T.
    Rensselaer Polytech Inst, USA.
    Gobeler, Norman
    University of Helsinki, Finland.
    Hassal, Emily
    Ontario Tech University, Canada.
    Huynh, Mercedes
    Wilfrid Laurier University, Canada.
    Hylander, Samuel
    Linnéuniversitetet.
    Jonasen, Kacie L.
    Purdue University, USA.
    Kirkwood, Andrea
    Ontario Tech University, Canada.
    Langenheder, Silke
    Uppsala universitet.
    Langvall, Ola
    Sveriges lantbruksuniversitet.
    Laudon, Hjalmar
    Sveriges lantbruksuniversitet.
    Lind, Lovisa
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Lundgren, Maria
    Linnéuniversitetet.
    Moffett, Emma R.
    University of California, USA.
    Proia, Lorenzo
    University of Vic–Central-University of Catalonia (Uvic–UCC), Spain.
    Schuler, Matthew S.
    Montclair State University, USA.
    Shurin, Jonathan B.
    University of California San Diego, USA.
    Steiner, Christopher F.
    Wayne State University, USA.
    Striebel, Maren
    Carl-von-Ossietzky University Oldenburg, Germany.
    Thibodeau, Simon
    Group de Research Interuniversitaire en Limnologie (GRIL), Canada; Université du Québec à Montréal, Canada.
    Cordero, Pablo Urrutia
    Uppsala universitet; Lunds universitet.
    Vendrell-Puigmitja, Lidia
    University of Vic–Central-University of Catalonia (Uvic–UCC), Spain.
    Weyhenmeyer, Gesa A.
    Uppsala universitet.
    Derry, Alison M.
    Group de Research Interuniversitaire en Limnologie (GRIL), Canada; Université du Québec à Montréal, Canada.
    Widespread variation in salt tolerance within freshwater zooplankton species reduces the predictability of community-level salt tolerance2023In: Limnology and Oceanography Letters, E-ISSN 2378-2242, Vol. 8, no 1, p. 8-18Article in journal (Refereed)
    Abstract [en]

    The salinization of freshwaters is a global threat to aquatic biodiversity. We quantified variation in chloride (Cl-) tolerance of 19 freshwater zooplankton species in four countries to answer three questions: (1) How much variation in Cl- tolerance is present among populations? (2) What factors predict intraspecific variation in Cl- tolerance? (3) Must we account for intraspecific variation to accurately predict community Cl- tolerance? We conducted field mesocosm experiments at 16 sites and compiled acute LC(50)s from published laboratory studies. We found high variation in LC(50)s for Cl- tolerance in multiple species, which, in the experiment, was only explained by zooplankton community composition. Variation in species-LC50 was high enough that at 45% of lakes, community response was not predictable based on species tolerances measured at other sites. This suggests that water quality guidelines should be based on multiple populations and communities to account for large intraspecific variation in Cl- tolerance.

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    fulltext
  • 44. Aroua, S.
    et al.
    Rousseau, K.
    Schmitz, Monika
    Chang, C.F.
    Elie, P.
    Dufour, S.
    The Gonadoliberin(s)-gonadotropin(s) axis in the eel: expression and regulation under induced maturation and sex steroid feedbacks2007Conference paper (Refereed)
  • 45.
    Arvidsson, Björn
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Flodpärlmussla - vad behöver vi göra för att rädda arten?2006Report (Refereed)
  • 46.
    Arvidsson, Björn
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Värmländsk nartur - värd att skydda och vårda2007Chapter in book (Refereed)
  • 47.
    Arvidsson, Björn
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Hultman, Jens
    Österling, Martin
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Öringtäthet och rekrytering hos flodpärlmussla2006Chapter in book (Other academic)
  • 48.
    Arvidsson, Björn
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Karlsson, Jens
    Flodpärlmusslan - skogsbäckarnas aristokrat2004Chapter in book (Refereed)
  • 49.
    Arvidsson, Björn
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Karlsson, Jens
    Recruitment in populations of freshwater pearl mussel (Margritifera margaritifera) in relation to population size and host density2004Conference paper (Refereed)
  • 50.
    Arvidsson, Björn
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Karlsson, Svante
    Mer värld i Värmland och mer Värmland i världen2007Chapter in book (Refereed)
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