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  • 1.
    Abbott, Jessica K.
    et al.
    Lund University.
    Chippindale, Adam K.
    Queens University, Biol Dept, Kingston, ON, Canada..
    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 patternsIn: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101Article 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.

  • 2.
    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, ISSN 2050-3385, E-ISSN 2050-3385, Vol. 6, p. 1-7, 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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  • 3.
    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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  • 4. Affonso, Igor de Paiva
    et al.
    Karling, Leticia Cucolo
    Takemoto, Ricardo Massato
    Gomes, Luiz Carlos
    Nilsson, Per Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    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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  • 5.
    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.

  • 6.
    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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  • 7.
    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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    Sinnen
  • 8.
    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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  • 9.
    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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  • 10.
    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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  • 11.
    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)
  • 12.
    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.

  • 13.
    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)
  • 14.
    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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  • 15.
    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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  • 16.
    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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  • 17.
    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)
  • 18.
    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.

  • 19.
    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)
  • 20.
    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)
  • 21.
    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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  • 22.
    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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  • 23.
    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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  • 24. 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.
  • 25.
    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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  • 26.
    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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  • 27.
    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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  • 28.
    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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  • 29.
    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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  • 30.
    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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  • 31.
    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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  • 32. 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

  • 33. 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)
  • 34.
    Arvidsson, Björn
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Flodpärlmussla - vad behöver vi göra för att rädda arten?2006Report (Refereed)
  • 35.
    Arvidsson, Björn
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Värmländsk nartur - värd att skydda och vårda2007Chapter in book (Refereed)
  • 36.
    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)
  • 37.
    Arvidsson, Björn
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Karlsson, Jens
    Flodpärlmusslan - skogsbäckarnas aristokrat2004Chapter in book (Refereed)
  • 38.
    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)
  • 39.
    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)
  • 40.
    Arvidsson, Björn L
    et al.
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Karlsson, Jens
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Österling, Martin E
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Recruitment of the threatened mussel Margaritifera margaritifera in relation to mussel population size, mussel density and host density2012In: Aquatic conservation, ISSN 1052-7613, E-ISSN 1099-0755, Vol. 22, p. 526-532Article in journal (Refereed)
    Abstract [en]

    Anthropogenic, abiotic factors are considered main causes of recruitment failure of unionid mussels, including the freshwater pearl mussel (Margaritifera margaritifera). In this large-scale investigation, we instead examined the relationship between biotic factors and mussel recruitment.

    Juvenile mussel density was positively related to both mussel population size and density of which the last appeared to be a more accurate measure of recruitment.Host fish density of young-of-the-year and older brown trout (Salmo trutta) were positively related to recruitment. Moreover, the mean density of both age classes of fish, when grouped into density classes was positively related to juvenile mussel density, an effect that decreased at trout densities above 10 trout 100 m-2.There was a higher relative importance of mussel population size and density than trout density to recruitment.To increase recruitment of juvenile mussels, managers may apply measures that increase mussel density, and trout density up to about 10 trout 100 m-2 in connection to mussel beds. Mussel beds may also be managed and one possible measure within small and sparse mussel populations may be to concentrate the remaining mussels to areas where trout density is high. Likewise, young-of-the-year trout may also be moved to areas of high mussel density, as young trout individuals are relatively resident during their first year. This may increase mussel larval infection rates and mussel recruitment.

  • 41.
    Arvidsson, Björn
    et al.
    Karlstad University, Faculty of Social and Life Sciences.
    Söderberg, Håkan
    Flodpärlmussla - vad behöver vi göra för att rädda arten?: En workshop på Karlstads universitet2006Report (Other scientific)
    Abstract [sv]

    Flodpärlmusslans situation i Sverige är bekymmersam, och i en stor del av de återstående populationerna sker ingen nyrekrytering av små musslor. För att belysa kunskapsläget om flodpärlmusslans situation och för att diskutera olika åtgärdsmöjligheter genomfördes i november 2005 en work shop vid Karlstads universitet med deltagande av naturvårdare från olika myndigheter och forskare. Vid mötet presenterades aktuell forskning i Skandinavien och olika uppföljningar som sker i olika myndigheters regi. Mötet bekostades av länsstyrelsen i Västernorrland, som fått ett nationellt ansvar att ta fram ett åtgärdsprogram för arten. I denna sammanställning redovisas en del av de föredrag och diskussioner som förekom vid mötet.

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  • 42.
    Augustsson, Evelina
    Karlstad University.
    Seasonal variability in group size of harbor seals (Phoca vitulina) hauled out on glacial ice in Johns Hopkins Inlet, Glacier Bay National Park, Alaska2010Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Individuals are believed to benefit in various ways from living in groups. Some species aggregate to increase foraging efficiency and others for social benefits. Why pinnipeds rest in groups is yet not fully understood, but the most common ecological explanation is the benefit of enhanced predator detection. An alternative explanation for grouping, however, is limitation of resting sites, which might force individuals to aggregate on whatever sites are available, despite increased competition for food or mates. My study is focused on group size of harbor seals (Phoca vitulina) hauled out on glacial-ice sites in Glacier Bay National Park (GBNP), southeastern Alaska. Previous studies have focused on group size on terrestrial haul-out sites, and to date there have been few studies of group size on ice haul-out sites. In GBNP, peak numbers of harbor seals haul out during the pupping season (June) and the molting season (August). During the breeding season, glacial-ice haul-out sites are used primarily by females and pups, and during the molting season by molting seals. Because seals may group as an anti-predator strategy, I hypothesized that group size would differ between seasons, with smaller groups of mainly mothers and pups during June, and larger-sized groups during August. The aim of this study was to quantify seasonal differences in the group size of harbor seals hauled-out on glacial ice in Johns Hopkins Inlet (JHI), GBNP, southeastern Alaska, and in addition, map and evaluate the large-scale (inlet-level) spatial distribution of seals for both seasons. I used digital aerial survey photographs to map seal distributions. Four replicate aerial surveys were conducted in JHI during both June and August, 2007. Digital images were georeferenced and imported into ArcGIS 9.3 where the location of each seal was digitized, and group size calculated. To assess within- and between-season differences in spatial distribution of hauled-out seals, the location of each seal for each survey was plotted in ArcGIS, and compared to a visual assessment of ice coverage. My results show that harbor seals in JHI tend to haul out as single individuals during both seasons, with the exception of nursing mothers with pups in June, and a few larger-sized groups in August. There was no significant difference in group size between seasons. Group size during June varied very little, with almost all seals being either single or in mother-pup pairs. Group size varied more during August, and although most seals hauled out alone, there were a few larger-sized groups during each survey. The relative lack of grouping behavior is contrary to previous research, and it suggests that predation pressure on seals within JHI may be lower than at other sites. The greater frequency of larger-sized groups in August appeared to be related to reduced availability of glacial-ice haul-out sites. Long-term reduction in the availability of glacial-ice haul-out sites in JHI, therefore, might lead to shifts in haul-out behavior of harbor seals, with more seals being forced to haul out in larger groups.

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  • 43. Aurora, S.
    et al.
    LeBelle, N.
    Schmitz, Monika
    Dufours, S.
    In vitro regulation by activinB and IGF-I of gonadotropin expression in European eel, Anguilla anguilla2007Conference paper (Refereed)
  • 44. Aurora, S.
    et al.
    Schmitz, Monika
    Weltzin, F.A.
    Baloche, S.
    LeBelle, N.
    Rousseau, K.
    Dufours, S.
    Differential expression of LHbeta and FSHbeta in European eel, Anguilla anguilla2006Conference paper (Refereed)
  • 45.
    Axelsson, Tomas
    Karlstad University, Faculty of Social and Life Sciences.
    Kantzonsvegetationens inverkan på dieten hos öring (Salmo trutta) i en skogsbäck2008Independent thesis Basic level (professional degree), 20 points / 30 hpStudent thesis
    Abstract [en]

    The effects on the diet of brown trout (Salmo trutta) of a clear cutting of the riparian vegetation has been investigated in a field-experiment, where two of the potential effects of a clear cut were simulated. The focus was placed on the two factors increased light and input of terrestrial invertebrates. The increase of ligth was manipulated by placing fluorescent lights over the brook and the input of terrestrial invertebrates was manipulated by placing plastic tents over the brook. Issues discussed are the percentage terrestrial food in the different treatments and at the different times of sampling, differences in the percentage terrestrial food between older and younger individuals of brown trout, differences in the amount of aquatic food in the light-treatment and a taxonomic summary of the composition of the diet. There were significant differences between the the different treatments, where the individuals in the control treatment ate significantly more terrestrial food as compared to the individuals in the tent and in the combined light and tent treatment. There was also a significant difference between the different times of sampling, more terrestrial food was consumed later in the season. No sigificant differences were detected between older and younger individuals concerning the percentage of terrestrial food eaten, nor between the different treatments concearning the amount of aquatic food consumed. The aquatic food showed a wider variation and was more diverse as compared to the terrestrial food, and earthworms (Lumbriculidae) was a very common food item.

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  • 46.
    Backius, Helena
    Karlstad University, Faculty of Social and Life Sciences, Department of Biology.
    Förändring av kärlväxters artsammansättning vid återupptagen hävd i skogligt avgränsade ängs- och hagmarker2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Old agricultural landscapes house a great biodiversity. To conserve this diversity the European Union award financial support in the form of environmental grants to encourage farmers to maintain pastures and hay meadows using old-fashioned methods. But are the measures effective and do they meet their purpose? The purpose of this study was to re-inventory ten sample plots from 2002 on the farm Brofallet to see how species composition of vascular plants had been affected by the nine seasons of using these old-fashioned methods management. The farm is completely surrounded by forest, isolated from other agricultural land. No significant overall change was observed concerning the composition of vascular plant species favored by traditional management. Qualitative observations, however, showed an increase in some species favored by traditional management. The conclusion is that the five-year commitment that farmers make to receive the environmental grants is not adequate enough to be able to detect changes in total diversity of vascular plants on a farm such as Brofallet, but that changes may occur faster at other levels in the ecosystem. Moreover, a ramification of this study is the idea that even environmental measures and documentation should be characterized by diversity. In summary, small-scale extensive farming may prove to be important in the overall quest for a sustainable society, both to exploit land for food production using extensive farming, and to maintain biodiversity at the landscape level.

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  • 47.
    Bains, Sandra
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Flodpärlmusslans (Margaritifera margaritifera) påverkan på öringens (Salmo trutta) tillväxt och rörelsemönster2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Flervärdsparasiter är kända för att påverka en rad egenskaper såsom morfologi, fysiologi och beteende hos sin värd. Envärdsparasiter såsom flodpärlmussla (Margaritifera margaritifera) lever som larver inkapslade i gälarna på öring (Salmo trutta), men påverkar troligtvis inte sin värd i samma utsträckning som flervärdsparasiter. Detta eftersom de är beroende av värdens överlevnad. Dock har negativa effekterna av envärdsparasiter observerats, såsom minskad framgång i aktiviteter till exempel födosök, aggressiv konkurrens, uppvakning och ungvård. En minskad framgång i födosök kan komma att påverka värdens tillväxt och därmed överlevnad.I denna studie undersöktes påverkan av flodpärlmusslans larver på öringars tillväxt, konditionsfaktor, och rörelsemönster. Analyser av data från två studieområden i Älgåälven indikerade att flodpärlmusslans larver inte har någon signifikant påverkan på värdens tillväxt eller konditionsfaktorn. Regressionsanalyser visade även att det inte finns något signifikant samband mellan infektionsgraden och konditionsfaktorn.Resultaten tydde även på att flodpärlmusslans larver inte påverkar öringens rörelseförmåga då ingen signifikant skillnad i antal stationära individer kunde påvisas mellan låg- och höginfekterade öringar. Analyserna indikerade även på att det inte fanns någon signifikant skillnad i antal uppströms/nedströms mellan höginfekterade och låginfekterade individer. Det fanns inte heller någon signifikant skillnad i hur långt en individ förflyttade sig beroende på deras infektionsgrad. Sammantaget verkar det som att parasitinfektionen inte har någon stor negativ påverkan på värden.

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    fulltext
  • 48.
    Balk, Lennart
    et al.
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Hagerroth, Per-Ake
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Gustavsson, Hanna
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Sigg, Lisa
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Åkerman, Gun
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Ruiz Munoz, Yolanda
    Univ Vigo, Dept Biochem, Genet & Immunol, Lagoas Marcosende, ES-36310 Vigo, Spain.
    Honeyfield, Dale C.
    Leetown Sci Ctr, No Appalachian Res Lab, S Geol Survey USGS, Wellsboro, PA 16901 USA.
    Tjärnlund, Ulla
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.
    Oliveira, Kenneth
    Univ Massachusetts Dartmouth, Dept Biol, Dartmouth, MA 02747 USA.
    Strom, Karin
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.;Karolinska Inst, Dept Med Solna & Ctr Mol Med, SE-17176 Stockholm, Sweden.
    McCormick, Stephen D.
    Leetown Sci Ctr, Conte Anadromous Fish Res Lab, S Geol Survey USGS, Turners Falls, MA 01376 USA.
    Karlsson, Simon
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). Swedish Univ Agr Sci SLU, Inst Freshwater Res, Dept Aquat Resources, SE-17893 Drottningholm, Sweden..
    Ström, Marika
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden..
    van Manen, Mathijs
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden.;Univ Utrecht, Inst Risk Assessment Sci IRAS, NL-3508 TD Utrecht, Netherlands..
    Berg, Anna-Lena
    Med Prod Agcy, Box 26, SE-75103 Uppsala, Sweden..
    Halldorsson, Halldor P.
    Univ Icelands Res Ctr Sudurnes, IS-245 Sandgerdi, Iceland..
    Strömquist, Jennie
    Swedish Univ Agr Sci SLU, Inst Freshwater Res, Dept Aquat Resources, SE-17893 Drottningholm, Sweden..
    Collier, Tracy K.
    NW Fisheries Sci Ctr, NOAA Fisheries, Seattle, WA 98112 USA..
    Börjeson, Hans
    Swedish Univ Agr Sci SLU, Fisheries Res Stn, 13Department Aquat Resources, Brobacken, SE-81494 lvkarleby, Sweden..
    Morner, Torsten
    Natl Vet Inst SVA, Dept Dis Control & Epidemiol, SE-75189 Uppsala, Sweden..
    Hansson, Tomas
    Stockholm Univ, Dept Environm Sci & Analyt Chem ACES, SE-10691 Stockholm, Sweden..
    Widespread episodic thiamine deficiency in Northern Hemisphere wildlife2016In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, article id 38821Article in journal (Refereed)
    Abstract [en]

    Many wildlife populations are declining at rates higher than can be explained by known threats to biodiversity. Recently, thiamine (vitamin B-1) deficiency has emerged as a possible contributing cause. Here, thiamine status was systematically investigated in three animal classes: bivalves, ray-finned fishes, and birds. Thiamine diphosphate is required as a cofactor in at least five life-sustaining enzymes that are required for basic cellular metabolism. Analysis of different phosphorylated forms of thiamine, as well as of activities and amount of holoenzyme and apoenzyme forms of thiaminedependent enzymes, revealed episodically occurring thiamine deficiency in all three animal classes. These biochemical effects were also linked to secondary effects on growth, condition, liver size, blood chemistry and composition, histopathology, swimming behaviour and endurance, parasite infestation, and reproduction. It is unlikely that the thiamine deficiency is caused by impaired phosphorylation within the cells. Rather, the results point towards insufficient amounts of thiamine in the food. By investigating a large geographic area, by extending the focus from lethal to sublethal thiamine deficiency, and by linking biochemical alterations to secondary effects, we demonstrate that the problem of thiamine deficiency is considerably more widespread and severe than previously reported.

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    Balk2016
  • 49. Batool, Mustafa Kamil
    Stressnivå hos öring (Salmo trutta) - effekt  temperatur och predatornärvaro: Kortisolnivåer hos öring i akvariemiljö vid minskad temperatur och vid närvaro av lake (Lota lota)2018Student paper other, 10 credits / 15 HE creditsStudent thesis
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    fulltext
  • 50.
    Behrens, Jane W.
    et al.
    Technical University of Denmark.
    von Friesen, Lisa W.
    Lund University.
    Brodin, Tomas
    Swedish University of Agricultural Sciences (SLU) – Umeå.
    Ericsson, Philip
    Lund University.
    Hirsch, Philipp Emanuel
    University of Basel, Switzerland.
    Persson, Anders
    Lund University.
    Sundelin, Anna
    Umeå University.
    van Deurs, Mikael
    Technical University of Denmark.
    Nilsson, Per Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Personality- and size-related metabolic performance in invasive round goby (Neogobius melanostomus)2020In: Physiology and Behavior, ISSN 0031-9384, E-ISSN 1873-507X, Vol. 215, p. 1-6, article id 112777Article in journal (Refereed)
    Abstract [en]

    Differences between individuals in behavioral type (i.e. animal personality) are ecologically and evolutionarily important because they can have significant effects on fitness components such as growth and predation risk. In the present study we are used the invasive round goby (Neogobius melanostomus) from an established population in controlled experiments to examine the relationships among personality, metabolic performance, and growth rate (inferred as size-at-age). Boldness was measured as the time to return to normal behavior after a simulated predator attack, where fish with shorter freezing times were categorized as "bold" and fish with longer times were categorized as "shy." We show that bold fish have significantly higher standard metabolic rate (SMR) than their shy conspecifics, whereas there was no difference between personality types in their maximum metabolic rate (MMR) or aerobic scope (AS). Bold fish furthermore had a smaller size-at-age as compared to shy fish. Together this provides evidence of a metabolic underpinning of personality where the high-SMR bold fish require more resources to sustain basic life functions than their low-SMR shy conspecifics, indicating that bold round goby from established populations with high densities (and high competition for food) pay a price of reduced growth rate.

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