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  • 51.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Jurgensone, Iveta
    Rowe, Owen F.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Simonelli, Paolo
    Bignert, Anders
    Lundberg, Erik
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Karlsson, Jan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Can Humic Water Discharge Counteract Eutrophication in Coastal Waters?2013Inngår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 8, nr 4, s. e61293-Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A common and established view is that increased inputs of nutrients to the sea, for example via river flooding, will cause eutrophication and phytoplankton blooms in coastal areas. We here show that this concept may be questioned in certain scenarios. Climate change has been predicted to cause increased inflow of freshwater to coastal areas in northern Europe. River waters in these areas are often brown from the presence of high concentrations of allochthonous dissolved organic carbon ( humic carbon), in addition to nitrogen and phosphorus. In this study we investigated whether increased inputs of humic carbon can change the structure and production of the pelagic food web in the recipient seawater. In a mesocosm experiment unfiltered seawater from the northern Baltic Sea was fertilized with inorganic nutrients and humic carbon (CNP), and only with inorganic nutrients (NP). The system responded differently to the humic carbon addition. In NP treatments bacterial, phytoplankton and zooplankton production increased and the systems turned net autotrophic, whereas the CNP-treatment only bacterial and zooplankton production increased driving the system to net heterotrophy. The size-structure of the food web showed large variations in the different treatments. In the enriched NP treatments the phytoplankton community was dominated by filamentous >20 mu m algae, while in the CNP treatments the phytoplankton was dominated by picocyanobacteria <5 mu m. Our results suggest that climate change scenarios, resulting in increased humic-rich river inflow, may counteract eutrophication in coastal waters, leading to a promotion of the microbial food web and other heterotrophic organisms, driving the recipient coastal waters to net-heterotrophy.

  • 52.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Karlsson, Chatarina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Hajdu, Susanna
    Stockholms universitet.
    Höglander, Helena
    Stockholms universitet.
    Skjevik, Ann-Turi
    SMHI.
    Pelagial biologi / växtplankton2010Inngår i: Havet: om miljötillståndet i svenska havsområden. 2010 / [ed] Kristina Viklund (huvudredaktör) Ulrika Brenner, Annika Tidlund, Marie Svärd, Stockholm: Naturvårdsverket, 2010, s. 32-33Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 53.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Karlsson, Chatarina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Huseby, Siv
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Höglander, Helena
    Mer fosfor ger mer cyanobakterier i norra Östersjön2013Inngår i: Havet, s. 51-54Artikkel, forskningsoversikt (Annet vitenskapelig)
    Abstract [sv]

    I flera områden i norra Östersjön har cyanobakterierna ökat under de senaste tio till femton åren. I Bottenhavets och Egentliga Östersjöns kustområden ökar de kvävefixerande cyanobakterierna. I Bottenvikens utsjö är det den småcelliga och kolonibildande gruppen Chroococcales som blir fler. Förändringarna beror i flera fall på ökande halter av fosfor.

  • 54.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Meier, H.E. Markus
    Ripszam, Matyas
    Umeå universitet, Medicinska fakulteten, Institutionen för folkhälsa och klinisk medicin, Yrkes- och miljömedicin.
    Rowe, Owen
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Wikner, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Haglund, Peter
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Eilola, Kari
    Legrand, Catherine
    Figueroa, Daniela
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Paczkowska, Joanna
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Lindehoff, Elin
    Tysklind, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Kemiska institutionen.
    Elmgren, Ragnar
    Projected future climate change and Baltic Sea ecosystem management2015Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 44, nr Suppl 3, s. S345-S356Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Climate change is likely to have large effectson the Baltic Sea ecosystem. Simulations indicate 2–4 Cwarming and 50–80 % decrease in ice cover by 2100.Precipitation may increase *30 % in the north, causingincreased land runoff of allochthonous organic matter(AOM) and organic pollutants and decreased salinity.Coupled physical–biogeochemical models indicate that, inthe south, bottom-water anoxia may spread, reducing codrecruitment and increasing sediment phosphorus release,thus promoting cyanobacterial blooms. In the north,heterotrophic bacteria will be favored by AOM, whilephytoplankton production may be reduced. Extra trophiclevels in the food web may increase energy losses andconsequently reduce fish production. Future managementof the Baltic Sea must consider the effects of climatechange on the ecosystem dynamics and functions, as wellas the effects of anthropogenic nutrient and pollutant load.Monitoring should have a holistic approach, encompassingboth autotrophic (phytoplankton) and heterotrophic (e.g.,bacterial) processes.

  • 55.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Meier, Markus
    SMHI och Stockholms universitet.
    Hur påverkas Östersjön?2010Inngår i: Sverige i nytt klimat: våtvarm utmaning / [ed] Birgitta Johansson, Stockholm: Forskningsrådet Formas, 2010, s. 117-132Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 56.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Samuelsson, K
    Haecky, P
    Albertsson, J
    Changes in the pelagic microbial food web due to artificial eutrophication2006Inngår i: Aquat Ecol, Vol. 40, s. 299-313Artikkel i tidsskrift (Fagfellevurdert)
  • 57.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF). Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Selstam, Eva
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för fysiologisk botanik. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå Plant Science Centre (UPSC).
    Hagström, Åke
    Vertical transport of lipid in seawater1993Inngår i: Marine Ecology Progress Series, ISSN 0171-8630, E-ISSN 1616-1599, Vol. 98, nr 1-2, s. 149-155Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Lipids in seawater act as solvents and transporters of lipophilic organic pollutants. To investigate a possible transport route of lipophilic pollutants, the vertical flux of lipid was quantified during an annual cycle in the northern Baltic Sea. The lipid content in both sedimenting material and different size fractions of seawater was analyzed. During the year, 8 g lipid m-2 sedimented out from the photic zone to the benthic system. The sedimentation of lipid accounted for 300 to 400 % of the average standing stock of pelagic lipid and was concentrated in the spring bloom period (April-June) when 70 % of the total lipid sedimentation occurred. About 30 % of the produced pelagic lipid settled out from the system. In seawater the lipid maximum occurred at the end of the spring bloom, shortly after nutrient depletion, indicating a stress response in the algae. Since lipid sedimentation is concentrated in the spring bloom, removal of lipophilic organic pollutants may be important during this period.

  • 58.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Tamminen, Timo
    Lehtinen, Sirpa
    Jürgens, Klaus
    Labrenz, Matthias
    Viitasalo, Markku
    The pelagic food web2017Inngår i: Biological oceanography of the Baltic sea / [ed] Pauline Snoeijs, Hendrik Schubert, Teresa Radziejewska, Dordrecht: Springer Netherlands, 2017, s. 281-332Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]
    1. Environmental drivers and food web structure in the pelagic zone vary from south to north in the Baltic Sea. 
    2. While nitrogen is generally the limiting nutrient for primary production in the Baltic Sea, phosphorus is the limiting nutrient in the Bothnian Bay. 
    3. In the Gulf of Bothnia the food web is to a large extent driven by terrestrial allochthonous material, while autochthonous production dominates in the other parts of the Baltic Sea. 
    4. Changes in bacterioplankton, protist and zooplankton community composition from south to north are mainly driven by salinity. 
    5. Bacteria are crucial constituents of the pelagic food web (microbial loop) and in oxygen-poor and anoxic bottom waters where they mediate element transformations. 
    6. Diatoms and dinoflagellates are the major primary producers in the pelagic zone. Summer blooms of diazotrophic (nitrogen-fixing) filamentous cyanobacteria are typical of the Baltic Sea, especially in the Baltic Sea proper and the Gulf of Finland. 
    7. The mesozooplankton (mainly copepods and cladocerans) channel energy from primary producers and the microbial food web to fish and finally to the top predators in the pelagic system (waterbirds and mammals). 
    8. Herring and sprat populations are affected by the foraging intensity of their main predator (cod), and therefore the environmental conditions that affect cod may also influence mesozooplankton due to food web effects "cascading down the food web". 
    9. Anthropogenic pressures, such as overexploitation of fish stocks, eutrophication, climate change, introduction of non-indigenous species and contamination of top predators by hazardous substances, cause changes in the pelagic food web that may have consequences for the balance and stability of the whole ecosystem.
  • 59.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Wikner, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Klimatförändringar kan leda till mindre fisk i havet2016Inngår i: Havet: om miljötillståndet i svenska havsområden. 2015/2016, Göteborg: Havs- och vattenmyndigheten , 2016, s. 25-28Kapittel i bok, del av antologi (Annet vitenskapelig)
  • 60.
    Andersson, Agneta
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Wikner, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Umeå marina forskningscentrum (UMF).
    Pelagisk biologi2004Inngår i: Bottniska viken: årsrapport från den marina miljöövervakningen. 2003, Skydd av havsområden gagnar fisken, Hörnefors: Umeå marina forskningscentrum (UMF) , 2004, s. 11-13Kapittel i bok, del av antologi (Fagfellevurdert)
  • 61.
    Andersson, Amanda
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hållbar utveckling i kommuner: En studie om hur kommunerna i Norr- och Västerbotten arbetar med folkhälsomål och miljökvalitetsmål2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The purpose of this study was to investigate if the municipalities in Norrbotten and Västerbotten integrate the national environmental objectives and public health objectives in their work to achieve a sustainable development. Furthermore the purpose was to suggest different methods and tools to develop an integrated way of working with the objectives. Methods used were a literature study and a questionnaire, which was sent to people responsible for the objectives in each municipality. The result of this study indicates that most of the municipalities in Norrbotten and Västerbotten work extensively with environmental and public health objectives, but not in an integrated way. Methods like information in schools, closures and projects are used to implement the objectives in different municipal units. The result also indicates that public health is more considered in the municipalities than the environmental objectives. However, there was a will to expand the local work with the environmental objectives in the future. The conclusion of this study is that improvements can be done to develop and integrate public health and environmental issues in the municipalities in Norrbotten and Västerbotten. An integrated way of working with the objectives could include usage of indicators, such as unemployment or air particles, to measure the development and prioritize actions. It could also include participation in different networks to exchange experience within or between municipalities.

  • 62.
    Andersson, Anna
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Övervakning och uppföljning av utter i Västerbottens län2005Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
  • 63.
    Andersson, Bea Angelica
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Analysis of Selection and Genetic Drift in a Dioecious Plant: Spatial Genetic Structure and Selection in Phenotypic Traits in a Young Island Population of Silene dioica2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Selection and genetic drift are often competing forces in shaping genetic structure in populations. Genetic drift will often effectively cancel out the effect of selection when population sizes are small, such as in colonizing island populations. On a small island in the Skeppsvik Archipelago in northern Sweden, a newly founded population of Silene dioica has been monitored since it first established around 1993. Though inhabiting an area of merely 173 m2, the population has been shown to exhibit a genetically differentiated patch structure where closely related individuals are tightly grouped, distanced from other family groups. In this study, the effect of selection was evaluated as compared to that of genetic drift. Variation in phenotypic traits in flowers, leaves and stalks were compared to that of neutral markers, in the form of PST and FST measures, to assess a measure of what proportion of differentiation among patches in phenotypic traits could not be attributed to genetic drift. Males and females were analysed separately to obtain measures of sex specific selection. Signs of divergent and stabilizing selection were found in several traits in both males and females despite the small spatial scale and short time since colonization. Further analysis is needed to assess explanations for trait divergence among patches and direction of selection.

  • 64.
    Andersson, Elin
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hur långt har kommunerna kommit i arbetet med en hållbar mobilitetsutveckling?: En undersökning av bilens betydelse för samhället och hur kommuner idag arbetar med alternativa lösningar till det egna användandet av personbilen2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The purpose of this study was to investigate how the use of the private car has developed throughout history and to describe options for private use of private cars. The study aimed to investigate how municipalities in Sweden encourage and support their residents away from private car ownership to reduce car traffic. The study is based on literature research and a survey which were sent to 30 municipalities in Sweden to study the work of shared use of vehicle, shared mobility, combined mobility and mobility management interventions which aims to, by changing travellers’ attitudes and behaviour reduce private car use. Private cars are a major source to anthropogenic emissions of carbon dioxide which contributes to climate change and global warming. Renewable fuels and fuel efficient vehicles are part of the solutions for reducing the emission of carbon dioxide, but also reduce private car use. The result of the survey showed that mobility management interventions were most common. More than half of the municipalities offered shared mobility, especially the larger municipalities. Combined mobility was not offered by the municipalities today. Municipalities state that they are both working on a strategy to reduce private car use along with various other projects. Challenges with the strategies to reduce private car use were reported to be the work of getting different actors to move in the same direction, toward reduced emissions from private car use.

  • 65.
    Andersson, Emma
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Adaptive trait utility in the feeding apparatus of European whitefish (Coregonus lavaretus): Relationships between feeding morphology and maximum and minimum prey size in the diet of whitefish2015Independent thesis Advanced level (degree of Master (Two Years)), 40 poäng / 60 hpOppgave
    Abstract [en]

    Whitefish (Coregonus lavaretus) populations diverge into morphs that differ in body size along a benthic-limnetic axis and throughout the depth of the water column. This process is assumedly initiated by the presence of northern pike (Esox lucius) and is followed by morphological adaptations to available food resources. In this study eight populations of whitefish was studied with the purpose of increasing the knowledge about adaptive trait utility in the feeding apparatus of whitefish. This was done by analyzing the mean and absolute maximum and minimum prey size ingested by fish along four morphological trait gradients. The morphological traits was body size, gill raker number and density, and gape size. The results show clear evidence of morphological adaptations in both the benthic and limnetic habitat, furthermore, when comparing the two prey size responses (mean and absolute values) it becomes clear that none of the studied whitefish is physically constrained in terms of the largest prey they can ingest. However, large fish seem to be limited in eating small prey sizes. Interestingly, I also found strong indicators for filter feeding adaptation for one of the studied populations.  

  • 66.
    Andersson, Emma
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Metallkoncentrationer i sediment: Jämförelse mellan en fjällsjö och sjöar påverkad av gruvdrift2012Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Metal concentration (Pb,Cu, Zn and As) in alpine lake sediments in comparison to sediment affected by sulfidemining

    Many companies are prospecting for sulfide minerals in northern Sweden and mining activities in this area are likely to increase within the near future. The aim of this report was to estimate to what extent the metal concentration in lake sediments are expected to be altered by mining activities, by comparing the sediment concentrations in a pristine alpine lake sediment with that of sediment deposited in lakes near sulfide mines. Pristine lake sediments was collected from Lake Vuolep Silbbajávrre using a HTH sediment corer and analyzed using the X-ray fluorescence (XRF) while published metal concentrations from six mining lakes were used as a reference for the geochemical conditions in sulfide mining lakes. I found that sediment concentrations were typically hundred to thousand times higher in mining lakes compare to that in Vuolep Silbbajávrre. My results suggest that the metal loading in alpine lakes is expected to increase when sulfide mines are opening in Swedish sub-arctic alpine regions. The increase was especially high for As and Zn that showed the highest enrichments in the mining lakes in comparison to the alpine lake sediment. Higher concentrations of the metals are likely to have negative consequences for the benthic fauna having the sediment as habitat, considering that concentrations in the mining lakes sometimes exceed levels where negative biotic effects are expected. If the mineral exploration becomes a reality and new sulfide mines are opened in the Swedish alpine region, it will most likely result in a considerably increase in metal concentrations in nearby lakes.

  • 67.
    Andersson, Gabriella
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hantering av kemikalier och dess risker i frisörverksamheter2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The purpose of this study was to examine the hairdresser’s knowledge about the chemicals they handle in their business and how they were handling the chemicals and the risks that follows. 9 Salons were visited to gather information. The same questions were asked at the salons. A sample of hair color products was photographed to gather information about ingredients and labeling. The conclusions of the study were that hairdressers have good knowledge about the risks related to human health but they need to improve their knowledge when it comes to environmental risks. The deficiencies that were found were that they lack knowledge about the laws concerning the use and distribution of cosmetics products and that not all saloons are handling the hazardous waste and residues from treatments correctly. The risks that could follow are that not enough is done to protect human health and the environmental. To prevent that damage to human health and the environmental occurs they should use more sources that focus on health and environmental to gather information about the risks with the chemicals they are handling, they should also limit the treatments on children and always inform about the risks when they are using products that can cause an allergic reaction.

    Keywords: Risks hairdressing, cosmetics products, p-phenylenediamine, Toluene-2,5-diamine, ammonia.

  • 68.
    Andersson, Jana
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    En studie av gruvindustrins påverkan på ett akvatiskt system.: Brubäckens påverkan på Granforsmagasinet2005Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
  • 69.
    Andersson, Jannika
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    How does nutrients and light affect algal growth in Swedish headwater streams?: A study using nutrient diffusing substrate and natural gradients of light2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Gaining knowledge about what factors determine benthic algal biomass and productivity is vital for understanding food webs in aquatic systems, especially in woodland streams with naturally low rates of primary productivity. The aim of this study was to investigate what factors determine algal growth in Swedish headwater streams. Nutrients, in terms of nitrogen (N) and phosphorus (P), and light are factors known to affect algal growth. By using nutrient diffusing substrate (NDS) and different gradients of light, it was possible to test the importance of these factors. To determine the effect of the experiment, the study was carried out in a forested reference stream, which is largely shaded with extreme low nutrient levels, and in a stream running through a clear-cutting plantation with high nutrient levels and incident light. In the forested reference stream it became clear that algal growth increased by experimentally adding N (P<0.005), although light did not affect the productivity. In the stream running through the clear-cut, algal productivity increased significantly with higher levels of light (P<0.005), regardless of nutrient addition. The results from this study suggest that light only becomes the depending factor when sufficient amounts of nutrients are available. However, it is still unclear at what nutrient levels this shift occur, and therefore future research is recommended.

  • 70.
    Andersson, Jens
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    Effects of diet-induced resource polymorphism on performance in Arctic charr (Salvelinus alpinus)2003Inngår i: Evolutionary Ecology Research, Vol. 5, s. 213-228Artikkel i tidsskrift (Fagfellevurdert)
  • 71.
    Andersson, Jens
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Potentiell etablering av strandvegetation längs torrfåror: En pilotstudie av en modelleringsmodell för miljöanpassade flöden2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Running water is an ecosystem that has high biodiversity despite its relatively small presence on the planet in terms of area. Water is also one of the most affected ecosystems, where hydropower is one of the actors with great impact and widespread use. Hydropower production often change the flow regime in rivers and damages, among other things, the littoral zone which is dependent on a natural flow regime. Without the natural flow regime's disturbance, the natural flora of the littoral zone is either displaced by upland vegetation, or it the zone becomes barren. One way to mitigate the negative effects of hydropower on the ecosystem are realesing water with a natural-like temporal variation in the original reaches. Reaches are often completely dry when water is redirected in to pass the turbines in the hydropower station. Previously there have been no attempts in Sweden to model the riparian potential below the dams using a theoretical environmental flow regime. This paper shows a way to inventory the potential for vegetation establishment of the riparian zone by field inventory of suitable substrate for riparian vegetation. For the inventoried locations, models of environmental flow at four levels of discharge (5, 10, 15 and 20% of the mean annual discharge) are used to predict the potetial extent of riparian vegetation. The modeling is done in ArcGIS using the "Riparian Topoghraphy Tool." The modelling show how much of the potential of water that inundates the riparian zone at varying levels of the hydropower production loss.

  • 72.
    Andersson, Jens
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    The development of resource polymorphism – Effects of diet, predation risk and population dynamical feedbacks.2005Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    This thesis deals with the evolution of individuals within a species adapted to utilize specific resources, i.e. resource polymorphism. Although a well-known phenomenon, the understanding of the mechanisms behind is not complete. Considering the ruling theories, resource polymorphism is suggested to depend on severe competition for resources, the presence of open niches to be occupied leading to a reduction in competition, and disruptive selection where generalist are out-competed due trade-offs in foraging efficiency for different prey. In order to study resource polymorphism, I have used fish as the animal group in focus and the methods I have used range over laboratory experiments, field experiments, literature surveys and theoretical modelling.

    In my work, I have showed that different resource use induces different body shapes and that the rate of change is dependent of the encounter rate of different resources. The induced body changes partly led to increased foraging efficiency but surprisingly I did not find any trade-offs due to specialization. However, when studying predation risk in relation to resource polymorphism, my studies point towards that resource use and predation risk may act as balancing factors in such a way that disruptive selection can take place.

    My work also shows that population feedbacks have to be explored when considering the evolution of resource polymorphism. In pond and field experiments, I found that changes in resource densities affected the actual resource use despite previous adaptations to certain resources. By performing a literature survey, I found that cannibalism indirectly by its effect on population dynamics seems to facilitate the evolution of resource polymorphism. Modelling a size-structured population, I found that resource dynamics were stabilized, and the relative availability of different resources was levelled out due to cannibalism.

    Taken together, my studies strongly suggest that to understand the development of resource polymorphism in consumer populations, future studies have to include the effect of a dynamic environment both with respect to resources and predators.

  • 73.
    Andersson, Jens
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    Byström, Pär
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    Claessen, D
    Persson, Lennart
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    De Roos, A. M.
    Stabilization of population fluctuations due to cannibalism promotes resource polymorphism in fish2007Inngår i: American Naturalist, Vol. 169, s. 820-829Artikkel i tidsskrift (Fagfellevurdert)
  • 74.
    Andersson, Jens
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    Byström, Pär
    Claessen, David
    Persson, Lennart
    De Roos, André M.
    Resource polymorphism and population dynamical feedbacks in FishManuskript (Annet vitenskapelig)
  • 75.
    Andersson, Jens
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Byström, Pär
    Department of Aquaculture, Swedish University of Agricultural Sciences, Sweden.
    Persson, Lennart
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    De Roos, André M.
    Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, Netherlands.
    Plastic reources polymorphism: effects or resource availability on Arctic char (Salvelinus alpinus) morphology2005Inngår i: Biological Journal of the Linnean Society, ISSN 0024-4066, E-ISSN 1095-8312, Vol. 85, nr 3, s. 341-351Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Resource polymorphism has been suggested to be a platform for speciation. In some cases resource polymorphism depends on phenotypic plasticity but in other cases on genetic differences between morphotypes, which in turn has been suggested to be the ongoing development of a species pair. Here we study environmentally induced morphological differences in two age classes of Arctic char (Salvelinus alpinus) influencing char performance and diet in relation to resource availability. We found that structurally complex habitats with relatively lower zooplankton densities gave rise to individuals with a deeper body, and a downward positioned tip of the snout compared with individuals from structurally simple habitats with relatively higher zooplankton densities for both age classes. Environment also had an effect on foraging efficiency on zooplankton, with fish from structurally simple habitats had a higher foraging rate than fish from structurally complex habitats. Diet analyses showed that resource use in char mainly depends on the relative abundance of different resources. Therefore, to gain further understanding of resource polymorphism we suggest that future studies must include population dynamic feedbacks by the resources on the consumers.

  • 76.
    Andersson, Jens
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Johansson, Frank
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Söderlund, Tony
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Interactions between predator- and diet-induced phenotypic changes in body shape of crucian carp2006Inngår i: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 273, nr 1585, s. 431-437Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Predator cues and diet, when studied separately, have been shown to affect body shape of organisms. Previous studies show that the morphological responses to predator absence/presence and diet may be similar, and hence could confound the interpretation of the causes of morphological differences found between groups of individuals. In this study, we simultaneously examined the effect of these two factors on body shape and performance in crucian carp in a laboratory experiment. Crucian carp (Carassius carassius) developed a shallow body shape when feeding on zooplankton prey and a deep body shape when feeding on benthic chironomids. In addition, the presence of chemical cues from a pike predator affected body shape, where a shallow body shape was developed in the absence of pike and a deep body shape was developed in the presence of pike. Foraging activity was low in the presence of pike cues and when chironomids were given as prey. Our results thereby suggest that the change in body shape could be indirectly mediated through differences in foraging activity. Finally, the induced body shape changes affected the foraging efficiency, where crucians raised on a zooplankton diet or in the absence of pike cues had a higher foraging success on zooplankton compared to crucian raised on a chironomid diet or in the presence of pike. These results suggest that body changes in response to predators can be associated with a cost, in terms of competition for resources.

  • 77.
    Andersson, Jens
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Persson, Lennart
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Behavioural and morphological responses to cannibalism in Arctic charr (Salvelinus alpinus)2005Inngår i: Evolutionary Ecology Research, ISSN 1522-0613, E-ISSN 1937-3791, Vol. 7, nr 5, s. 767-778Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Question: Does cannibalism lead to resource polymorphism in young Arctic charr (Salvelinusalpinus, Pisces)?

    Hypothesis: Cannibals should evoke a low-activity morph that is well adapted to benthivorybut not planktivory, and which differs in morphology compared with a planktivorous morph.

    Methods: We reared young-of-the-year charr in laboratory aquaria with and without largercannibalistic charr present. Thereafter, we measured foraging efficiency on pelagic and benthicresources, swimming speed when foraging, and morphology of the young charr.

    Conclusions: Living among cannibals did not affect the morphology of the young charr. Italso did not affect the foraging efficiency of the young charr on the benthic resource. However,individuals from cannibal treatments swam closer and had lower foraging efficiency on thepelagic resource.

  • 78. Andersson, Jon
    et al.
    Dynesius, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hjalten, Joakim
    Short-term response to stump harvesting by the ground flora in boreal clearcuts2017Inngår i: Scandinavian Journal of Forest Research, ISSN 0282-7581, E-ISSN 1651-1891, Vol. 32, nr 3, s. 239-245Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We studied short-term ground vegetation responses to stump harvesting by recording the occurrence of all species of bryophytes, vascular plants and the cover of soil disturbance on 20 clearcuts in the Southern and Middle Boreal zone in northern Scandinavia. All 20 clearcuts were slash-harvested and scarified and 10 of the clearcuts were also stump-harvested. The added effect of stump harvesting was assessed by comparing stump-harvested clearcuts with non-stump-harvested clearcuts. We tested whether stump harvesting causes extra soil disturbance compared to conventional forestry and if stump harvesting is affecting the assemblage, species richness and occurrence of individual species of vascular plants and bryophytes in boreal clearcuts. Our results revealed that stump harvesting causes an increase in the area of disturbed soil surface compared to conventional harvesting. Four of the most commonly occurring plant species in this area were significantly affected by stump harvesting, and Vaccinium vitis-idaea had a median occurrence of only 20% of that in non-stump-harvested clearcuts. The large impact on some plant species from a relatively modest increase of soil disturbance caused by stump harvesting suggest that stumps, with their slightly elevated bases, contributes to the survival of certain species on clearcuts.

  • 79.
    Andersson, Jon
    et al.
    Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden.
    Hjältén, Joakim
    Department of Wildlife, Fish, and Environmental Studies, Swedish University of Agricultural Sciences, SE-901 83 Umeå, Sweden.
    Dynesius, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Long-term effects of stump harvesting and landscape composition on beetle assemblages in the hemiboreal forest of Sweden.2012Inngår i: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 271, s. 75-80Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Studies on the effects of stump harvesting on forest biodiversity are scarce and studies on long-term effects are until now non-existent. We evaluated such long-term effects by sampling beetles at 14 clear-cuts with and 14 clear-cuts without stump harvesting; harvesting had been done 21–28 years before this study. By using window traps, we collected 6429 individuals belonging to 432 species in 55 taxonomic families. To control for potentially confounding effects of among-site variations in landscape setting we also assessed forest age and volume of deciduous trees within the forest surrounding each site. The long-term effects from harvesting on beetle abundance, species richness and species composition was generally small in comparison to the influence of the characteristics of the surrounding forests. The species richness of the beetle family Latridiidae and the functional group fungivores appeared, however, to be negatively affected by the previous stump harvesting, while several other groups showed strong associations to the characteristics of the surrounding forest. We found little support for considerable long-term effects of stump harvesting on beetles flying in the stands. Long-term effects of stump harvesting at the landscape scale accumulated from harvest of many localities may still be severe, and should be the subject of future studies.

  • 80. Andersson, Jon
    et al.
    Hjältén, Joakim
    Dynesius, Mats
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Wood-Inhabiting Beetles in Low Stumps, High Stumps and Logs on Boreal Clear-Cuts: Implications for Dead Wood Management2015Inngår i: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 10, nr 3, artikkel-id e0118896Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The increasing demand for biofuels from logging residues require serious attention on the importance of dead wood substrates on clear-cuts for the many forestry-intolerant saproxylic (wood-inhabiting) species. In particular, the emerging harvest of low stumps motivates further study of these substrates. On ten clear-cuts we compared the species richness, abundance and species composition of saproxylic beetles hatching from four to nine year old low stumps, high stumps and logs of Norway spruce. By using emergence traps we collected a total of 2,670 saproxylic beetles among 195 species during the summers of 2006, 2007 and 2009. We found that the species assemblages differed significantly between high stumps and logs all three years. The species assemblages of low stumps, on the other hand, were intermediate to those found in logs and high stumps. There were also significant difference in species richness between the three examined years, and we found significant effect of substrate type on richness of predators and fungivores. As shown in previous studies of low stumps on clear-cuts they can sustain large numbers of different saproxylic beetles, including red-listed species. Our study does, in addition to this fact, highlight a possible problem in creating just one type of substrate as a tool for conservation in forestry. Species assemblages in high stumps did not differ significantly from those found in low stumps. Instead logs, which constitute a scarcer substrate type on clear-cuts, provided habitat for a more distinct assemblage of saproxylic species than high stumps. It can therefore be questioned whether high stumps are an optimal tool for nature conservation in clear-cutting forestry. Our results also indicate that low stumps constitute an equally important substrate as high stumps and logs, and we therefore suggest that stump harvesting is done after carefully evaluating measures to provide habitat for saproxylic organisms.

  • 81.
    Andersson, Marléne
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Spillningsinventering av brunbjörn i väglöst land: Ett kompletterande arbetet till Länsstyrelsens björnspillningsinventering i Västerbotten år 20142014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The lack of information regarding the distribution of Ursus arctos arctos in the mountains of Västerbotten, Sweden, has led to many important questions about the occurrence of bears in these areas. Species distributions models, like MaxEnt, have shown to be a useful tool in species management. The objective of this study was therefore to determine if the distribution of bears in the southern part of the mountain range in Västerbotten could be predicted with MaxEnt. Data on the distribution of bear droppings were collected in the study area and used together with environmental variables. The resulting model had an AUC-value of 0,76, which is considered as good from a statistical point of view. Logistic regression over transect sampels in the study area was used to determine which variables that were most important to the species distribution. The regression gave no reliable results because the number of observations was too low. However, the method could yield valuable information if the sampel size is large enough. A field study to collect droppings from bears were made in Girifjället (where the probability of finding traces of bears was particulary high according to the MaxEnt analysis). No droppings were found in the area, but droppings were collected during the field study in an area with lower prediction value (but still relatively high). This leads to the conclusion that this method, with a few modifications, could be used together with logistics regression to get a better understanding of the distribution of bears in remote areas.

  • 82.
    Andersson, Natalie
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Miljömål 17: Hållbar konsumtion: Ett försök att integrera den svenska konsumtionens globala miljöpåverkan med miljömålssystemet2011Independent thesis Advanced level (professional degree), 10 poäng / 15 hpOppgave
    Abstract [en]

    Environmental objective 17: Sustainable consumption - An attempt to integrate the global impact of the Swedish consumption with the environmental objectives system

     

    The aim of this report was to integrate the global impact of the Swedish consumption withthe environmental objectives system through presenting a suggestion for a seventeenth environmental objective – Sustainable consumption. How the Swedish consumption pressures the global environment and methods to measure the affects was investigated. The pressure was divided into five main fields: climate, air, water, land and chemicals. The impacton humans and the biodiversity was also discussed, as well as differences between how men and women affect the environment and get affected when the environment changes. Chosen methods for calculating the impact had to be able to measure the pressure the Swedish consumption has on the environment, and thus humans and the biodiversity. The results show that the Swedish consumption has large internal and external impact on the environment. The methods that met the reports criteria and were analyzed were environmental input-output analysis, ecological footprint, water footprint, carbon footprint and environmental space. An earlier proposal for a seventeenth environmental objective was reviewed, called Restricted environmental pressure in other countries. In the discussion anew environmental objective was presented together with six stage goals. They were based o nthe main fields of environmental pressure. The measuring methods that were suitable and complete were suggested as indicators, namely ecological footprint and carbon footprint. To integrate the global aspect of the Swedish consumption with the environmental politics it’spossible to introduce a new environmental objective. Sustainable consumption is an attempt to do that.

  • 83.
    Andersson, Niki
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Biology and biodiversity of tardigrades in the world and in Sweden: Current status and future visions2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Tardigrades are small water-dwelling invertebrates that can live almost anywhere in the world. Even though they are well-known our knowledge about them is still scarce. The aim of this study was therefore to explore our current knowledge about tardigrades by: (1) explore their global phylogeny and biogeography based on bioinformatics (2) screen for tardigrades in select locations of northern Sweden and compare with other Swedish locations, and (3) identify at least one tardigrade from northern Sweden and explore the published biomarkers for further identification. The bulk of this thesis was based on evaluation of the Silva database for analyzing SSU (small subunit) and LSU (large subunit) tardigrade sequences and create phylogenetic trees. Some initial lab work was performed using samples of moss and lichen from Piteå, Vindeln and Öland. Results show that only few countries have been explored with regard to tardigrades, and in Sweden more research have been performed in the south compared to the north. The phylogenetic trees give a rough overview of tardigrade relatedness but many of the sequences need to be improved and more sequence work from additional environments is needed. In the lab tardigrades were only found from the Piteå samples, and one of those was identified as Macrobiotus hufelandi, for which a new biomarker was created. Overall, tardigrade research need to continue and expand to other regions in order to understand how these organisms differ between different environments, and more work is needed to ensure higher quality of sequences added to databases.

  • 84.
    Andersson Nyberg, Adrian
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Combining hydrologic modelling and boundary shear stress estimates to evaluate the fate of fine sediments in river Juktån: Impact of ecological flows2018Independent thesis Advanced level (degree of Master (Two Years)), 40 poäng / 60 hpOppgave
    Abstract [en]

    Altered flow regimes following river regulation can result in significant changes in river bed geomorphology and subsequent negative ecological impacts caused by re-suspended sediments deposited on the riverbed. This study aimed to evaluate the consequences of implementing an ecological flow regime on sediments accumulated within the regulated river Juktån. Sediments were sampled and analysed for particle size distribution to estimate sediment stability. Flow alteration following the ecological flow regime was analysed with HEC-RAS unsteady flow simulation serving as a basis for calculations of forces acting to erode or retain deposited sediments. Additional analyses regarding critical flow were made with HEC-RAS steady flow simulation. Results show that 4 out of 15 cross-sections analysed would have the potential to erode and re-suspend sediments. The estimated average critical flow for when sediments become unstable with potential to re-suspend is 17 m3/s. The total sediment inventory of the studied reach is ~25000 ton, with ~3000-ton sediments potentially eroding into re-suspension. This is approximately 3% of river Umeälvens annual 100 000 ton suspended sediments before being regulated. Results indicate that river bed heterogeneity in river Juktån could benefit from implementing the ecological flow regime while not mobilizing such amounts of fine sediments that would cause clogging effects downstream the site of interest. The study also introduces the erosion rate equation which compares the annual erosion between two different flow regimes.

  • 85.
    Andersson, Peter
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    Arbetsmiljöarbete i små företag: En enkätundersökning om små företags kunskap om arbetsmiljölagen och arbete med arbetsmiljöfrågor2005Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
  • 86.
    Andersson, Robert
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    Miljöinventering och förbättringsmöjligheter: en studie av Länsstyrelsen Östergötland2008Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
  • 87.
    Andersson, Sara
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Nutrient cycling by the herbivorous insect Chrysomela tremulae: Nutrient content in leaves and frass and measurements of ingestion, egestion and exuviation rates2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Insect herbivory on forest canopies strongly affects ecosystem nutrient cycling and availability in a variety of ways, e.g. by changing the quantity, quality and timing of nutrient input to forest soils. A qualitative method for measurements of ingestion, egestion and exuviation rates of the insect Chrysomela tremulae on leaves of the hybrid Populus tremula x tremuloides were tested in this study with the aim to detect differences in relative nutrient cycling efficiencies. The assimilation efficiency (AD), efficiency of conversion of digested food (ECD) and efficiency of conversion of ingested food (ECI) increased from 1st, through 2nd and 3rd instar larvae with generally higher efficiencies for nitrogen than carbon. Effects on nutrient limitations for the insect were also tested by increasing the C:N ratio of insect diet. A carbohydrate solution was painted onto leaves which resulted in a significant increase in C:N (p<0.0001). This lead to a trend of lengthened developmental time for each ontogenetic stage, as well as higher ingestion rate and lower egestion- and exuviation rates. However, a different method of increasing the C:N ratio is recommended in future experiments since the leaves never truly absorbed the solution.

  • 88.
    Andersson, Simone
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Environmental Communication for sustainable development in Kenya: A qualitative study focusing on solid and liquid waste2018Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    This research has investigated how environmental communication is reaching out in urban Kenya and what knowledge and attitude exists. Key aim was finding what perception stakeholders had on effective ways to communicate to reach goals of a sustainable development. Focus laid on solid and liquid waste, because of great improvements needed in infrastructure and behavior. In addition, comparison was made to current sustainability goals. Qualitative interviews with semi structured questions were conducted in Kitengela (Kajiado county) and Machakos Town (Machakos county), with six different target groups each and a total of 48 respondents. General knowledge of possibilities to reuse and recycle solid waste was quite high, but sewage is not very common to refer to as a resource. The sensitization today on the issues was mainly through schools and media. A perception was that people don’t care or know, but there are conversations about the menace of litter and sometimes dirty water. Nearly 75 % said service of clean water and environment would be worth almost any price. Many expressed frustrations on the lack of management and implications that follow when wanting to act well or create awareness, but no system to support a sustainable behavior. Suggestions of communicative methods had emphasis on reaching all age groups where people gather, like schools and churches/mosques. The approach should be positive with concrete feedback on profits of sustainable living, while presenting a vivid vision for everyone to work towards.  

  • 89.
    Andersson, Therése
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Enskilda avlopp i Nordmalings kommun: Utvärdering av faktorer vid prioritering av inventeringsområden och krav på enskilda avlopp2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Individual Sewers in Nordmalings Municipality – Evaluation of Factors when Prioritizing Inventory Areas and Demands of Individual Sewers

    The purpose of this study was to examine what to consider when prioritising inventory areas for individual sewers, as well as how an inventory should be initiated in Nordmalings municipality. The information was gathered by studying legislation, documents by government agencies, maps and by conducting a questionnaire survey. The study showed that the demands on individual sewers must be separately determined in every individual case. Sewer system shall have further wastewater treatment than only septic tanks, for example an infiltration plant. The demands should be determined by the protection level of the Environmental Protection Agency's guidelines (NFS 2006:7) for small sewage systems for domestic wastewater. The areas demanding a high level of protection are sensitive to emissions from individual sewers. Such areas can for example be Natura 2000, bathing places and water that is sensitive to eutrophication. The questionnaire was sent to 85 property owners and 64 of them responded. The majority of the ones with permanent housing had septic tanks (90.5 %) and an infiltration plant (60.0 %). The questionnaire indicated that the majority of the individual sewers were acceptable but that a significant part may have serious flaws. Prioritisation of inventory areas can be based on the areas that need high level of protection. Based on these results, coastal areas in Nordmalings municipality should be prioritised for an inventory of individual sewers.

  • 90.
    Andersson, Tord
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Mercury and radiocesium in Swedish lakes1993Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    Two large, nationwide monitoring data sets were compiled and statistically treated in order to create a national picture of the problems with high contents of mercury (Hg) and radiocesium (137Cs) in fish. Beside these two data sets, 75 lakes in four counties (Västernorrland, Gävleborg, Örebro and Kronoberg) were studied in connection to an evaluation of different measures to decrease the content of Hg and 137Cs in fish. An important objective was to investigate and determine the relationship between the content in fish and the load of the elements and how this relationship was affected by different abiotic lake characteristics. Several alternatives to measure the lake doses of Hg and 137Cs were evaluated (concentration in different fractions in lake water, in settling particles, and in surface sediments).

    About 10000 Swedish lakes were calculated to have a mean Hg content in 1-kg pike (FHg) above 1 mg kg-1 (wet weight) in the end of 1980’s, that is a 5-fold increase compared to the calculated preindustrial mean value. The cumulated domestic Hg- sources of emission make the largest contribution to the presently high mercury levels in pike and particularly so in central and northern Sweden.The second most important cause is acidification and thirdly Hg emissions from European sources. The content of 137Cs in fish normalized to 100 g perch (FCs) was above the limit for commercial sale, 1500 Bq kg-k in about 14000 Swedish lakes during autumn of 1987.

    An empirical model including Chernobyl fallout, hydraulic residence time and ionic strength explained almost 60 % of the inter-lake variation in FCs. At the same level of fallout, this difference in lake sensitivity, gave a tenfold difference in the initial transfer from fallout to small perch. A significant relationship was demonstrated between the lake dose of 137Cs and the content in fish. No such clear relationship existed for Hg due to the much more complex chemical and biological behaviour of Hg, where especially factors affecting méhylation and food web structure seems crucial. Lakes with a low relative sedimentation of Hg did also have a low relative sedimentation of 137Cs due to differences in particle sedimentation rates between the lakes. The sedimentation rate of radiocesium was well correlated to the natural concentration of major base cations and intercorrelated parameters such as pH, alkalinity and conductivity. The higher scavenging capacity in lakes with higher concentration of major base cations was due to higher particle sedimentation rates and higher K<i values in these lakes. However, the water chemistry was probably not causal in this respect, despite the high correlation, the distribution and sedimentation coefficients for radiocesium was not notably affected of the increased mean concentration of major base cations after liming and potash addition. It is suggested that a likely causal factor rather would be the amount and nature of scavenging agents (possibly clay minerals), which in these lakes was indicated by the natural concentration of base cations in the water.

    In general, the remedial measures gave the intended water chemical response with substantially increased mean values of alkalinity, hardness and pH. Two years after the start of the remedies, the Hg concentration in small perch (Hg-pe) was reduced by about 30% on average. The sedimentation rate of Hg decreased during 1988 and 1989 (i.e. after remedial measures) in contrast to the mean concentration of total Hg in water, thus, the retention decreased. None of the methods applied gave any rapid and clear reduction in the concentrations of 137Cs in fish, in comparison with lakes where the water chemical or biological conditions not were changed.

  • 91.
    Andersson, Tove
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Lövgren, Lars
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Persson, Per
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Kemi.
    Giesler, Reiner
    Ekologi, miljö och geovetenskap.
    Adsorption of Monomethyl Phosphate to the Goethite (-FeOOH)/water Interface2002Konferansepaper (Annet vitenskapelig)
  • 92.
    Andersson, Veronica
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Miljö- och hälsoeffekter vid bränder: En uppskattning av bränders bidrag till den totala miljöpåverkan i Västerbottens län2011Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    Environmental and health effects caused by fires - Estimating the contribution of accidental fires to the overall environmental impact in the county of Västerbotten

    The purpose of this study was to examine the extent of emissions of volatile organic compounds (VOCs), polycyclic aromatic hydrocarbons (PAHs) and dioxins, caused by fires, and the relative environmental impact of fires compared with other sources to the county of Västerbotten, Sweden. Estimated levels of fire impact in Västerbotten were based on previously estimated emission levels of VOCs, PAHs and dioxins from fires occurring in 1999 in Sweden. An average of the number of fires and levels of VOCs, PAHs and dioxins generated by other emission sources into the air in the county of Västerbotten was also taken into account. By comparing emission levels of fires and the emission levels of other sources in the county of Västerbotten, the results showed that among other things, dioxin levels from fires were estimated to be as large as emissions from the transport sector. PAH levels in fires are equal to emissions from the energy supply in Västerbotten, such as thermal power stations etc. However, fire emissions of VOC are only 10% of compared to the international air- and sea traffic emissions. Overall, emissions of VOC, PAH and dioxins caused by fires are negligible in comparison to the total environmental impact in the county of Västerbotten.

  • 93.
    Androsiuk, P.
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap. University of Warmia & Mazury, Poland.
    Shimono, A.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Westin, J.
    Lindgren, D.
    Fries, A.
    Wang, X. -R
    Genetic status of Norway spruce (Picea abies) breeding populations for northern Sweden2013Inngår i: Silvae Genetica, ISSN 0037-5349, Vol. 62, nr 3, s. 127-136Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Efficient use of any breeding resources requires a good understanding of the genetic value of the founder breeding materials for predicting the gain and diversity in future generations. This study evaluates the distribution of genetic variation and level of relatedness among and within nine breeding populations of Norway spruce for Northern Sweden using nuclear microsatellite markers. A sample set of 456 individuals selected from 140 stands were genotyped with, 15 SSR loci. Over all loci each individual was identified with unique multilocus genotype. High genetic diversity (average H-e=0.820) and low population differentiation (F-ST = 0.0087) characterized this material. Although low in F-ST, the two northernmost populations were clustered as a distinct group diverged from the central populations. The population differentiation pattern corresponds well with the post glacial migration history of Norway spruce and the current gene flow and human activity in the region. The average inbreeding coefficient was 0.084 after removal loci with high frequency of null alleles. The estimated relatedness of the trees gathered in the breeding populations was very low (average kinship coefficient 0.0077) and not structured. The high genetic variation and low and not structured relatedness between individuals found in the breeding populations confirm that the Norway spruce breeding stock for northern Sweden represent valuable genetic resources for both long-term breeding and conservation programs.

  • 94.
    Andrée, Erik
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Schütte, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Matavfall från livsmedelsbutiker: - En analys av den kommunala hanteringen i Sverige samt en detaljstudie av förhållandena i Umeå kommun2010Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Food waste from grocery stores - An analysis of municipal management inSweden and a detailed study of the situation in Umeå municipality

    The objective of this thesis was to analyze the municipal management of food waste fromgrocery stores in Sweden in general and in Umeå municipality in particular. Furthermore theobjective was to account for the different waste treatment methods that can be used and toevaluate them from an environmental perspective. In order to analyze the municipalmanagement a survey was sent to all of the municipalities/municipal waste companies inSweden. A general comparison of treatment methods was carried out on the basis of ascientific review and a system analysis was performed in order to compare three differenttreatment alternatives for the food waste generated in grocery stores in Umeå. The surveyshowed that the legal definition of food waste from grocery stores is unclear and variesbetween municipalities. However, a majority of the municipalities that offer any kind ofsource separation include grocery stores in the offer. The packaged food waste is oftenincinerated even if source separation is available due to the difficulties with removingpackaging materials. Concerning treatment methods, the results show that composting is theenvironmentally least advantageous method for large-scale treatment of food waste.Incineration and anaerobic digestion are about equal in their environmental impact, but thelatter was found to be favorable in principle based on the fact that it, in theory, generates bothnutrient recycling and energy recovery. For the food waste generated in grocery stores inUmeå municipality, incineration at the Dåva power and heating plant was found to be thepreferable method rather than anaerobic digestion in Skellefteå and composting in Luleå.

  • 95. Angelstam, Per
    et al.
    Roberge, Jean-Michel
    Axelsson, Robert
    Elbakidze, Marine
    Bergman, Karl-Olof
    Dahlberg, Anders
    Degerman, Erik
    Eggers, Sönke
    Esseen, Per-Anders
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Hjältén, Joakim
    Johansson, Therese
    Müller, Jörg
    Paltto, Heidi
    Snäll, Tord
    Soloviy, Ihor
    Törnblom, Johan
    Evidence-Based Knowledge Versus Negotiated Indicators for Assessment of Ecological Sustainability: The Swedish Forest Stewardship Council Standard as a Case Study2013Inngår i: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 42, nr 2, s. 229-240Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Assessing ecological sustainability involves monitoring of indicators and comparison of their states with performance targets that are deemed sustainable. First, a normative model was developed centered on evidence-based knowledge about (a) forest composition, structure, and function at multiple scales, and (b) performance targets derived by quantifying the habitat amount in naturally dynamic forests, and as required for presence of populations of specialized focal species. Second, we compared the Forest Stewardship Council (FSC) certification standards' ecological indicators from 1998 and 2010 in Sweden to the normative model using a Specific, Measurable, Accurate, Realistic, and Timebound (SMART) indicator approach. Indicator variables and targets for riparian and aquatic ecosystems were clearly under-represented compared to terrestrial ones. FSC's ecological indicators expanded over time from composition and structure towards function, and from finer to coarser spatial scales. However, SMART indicators were few. Moreover, they poorly reflected quantitative evidence-based knowledge, a consequence of the fact that forest certification mirrors the outcome of a complex social negotiation process.

  • 96.
    Angermund, Anna-karin
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Påverkar ålder och kön mönster i vårmigration hos snösparv (Plectrophenax nivalis)?2017Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [en]

    In many bird species protandry is a common pattern during their spring migration, allegedly this pattern is also present for the passerine species snow buntings (Plectrophenax nivalis). During their spring migration males tends to arrive 3-4 weeks before the arrival of females at the breeding grounds. In this study I have examined if this pattern is reflected in their spring migration as well if there is a differential timing between the age classes for males. I also examined if there is a connection between wingspan and arrival time at Umeå delta for each sex and between the sexes. To make this study possible I captured and banded snow buntings during spring at Umedeltat field station and combined my data with 2012’s data of banded snow buntings from the same station. There was a significant difference in mean capture dates between males and females, with males arriving 1.6 days earlier. There was also a significant difference in mean capture dates between older and younger males, older males arriving 2.7 days earlier. When I examined the wingspan for the sexes I looked at it for each year. During 2017 there was a trend for females that those with longer wingspan arrived earlier than females with shorter wingspan. During 2012 there was a significant correlation; females with longer wingspan arrived earlier than those females with shorter wingspan. There was no correlation between males each year. I also found that in 2017 the mean captures dates for males was later than in 2012. In contrast mean capture dates for females was earlier 2017 than in 2012. My data strongly indicate that protandry is present in snow buntings as well as wingspan may have greater importance for females during their migration than males.

  • 97.
    Anglid, Catrin
    et al.
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    Nordlund, Laila
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    Tysta miljöer i Umeå kommun: - Håller de tätortsnära rekreationsområdena måttet?2005Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
  • 98.
    Annerstedt, Elin
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Djurplågeri: En analys av domar i Sverige- Hur förekommande är djuplågeri och finns det några trender?2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [en]

    The aim of this study was to investigate the incidence of animal cruelty in Sweden, and to find out if there are any trends. The study is based on convictions and number of convicted people for animal cruelty in 2011 and 2013. The result showed that animal cruelty had low incidence. The results with regard of trends showed that pets are more common than farm animals and that dogs was the most occurring specie. The result also showed that men and persons in the age of 45-64 years was the two most overrepresented categories of people when it comes to animal cruelty. The area around Stockholm was the most represented geographical area. A large number of animal cruelty offenses may not be recognized and/or lead to prosecution. This may be because of the absence of visible injuries on account of animal abuse, fear and that animal cruelty offenses occur where the public has no insight. There were no increase in animal cruelty from the year 2011 to 2013, this may be due to the fact that animal cruelty offenses are not prioritized by the police. Based on this study it is evident that more focus need to be placed on animal cruelty crimes.

  • 99.
    Appelqvist, Peter
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    Mätningar och beräkningar av NO2-halter i Helsingborg2004Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
  • 100. Araki, N.H.T.
    et al.
    Khatab, I.A.
    Hemamali, K.K.G.U.
    Inomata,, N.
    Wang, Xiao-Ru
    Umeå universitet, Teknisk-naturvetenskaplig fakultet, Ekologi, miljö och geovetenskap.
    Szmidt, A.E.
    Phylogeography of Larix sukaczewii Dyl. and Larix sibirica L. inferred from nucleotide variation of nuclear genes2008Inngår i: Tree Genetics & Genomes, Vol. 4, s. 611-623Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We investigated phylogeography of Larix sukaczewii and Larix sibirica using nucleotide variation at three following nuclear gene regions: 5.8 S rDNA including two internal transcribed spacers (ITS), cinnamyl alcohol dehydrogenase (CAD), and phytochrome-O (PHYO). We also included sequences of the 4-coumarate: coenzyme A ligase (4CL) gene region obtained in our recent study. CAD and PHYO showed very low nucleotide variation, but ITS and 4CL had levels of variation similar to those reported for other conifers. Pleistocene refugia have been hypothesized to exist in the Southern Urals and South Central Siberia, where four out of nine of the investigated populations occur. We found moderate to high levels of population differentiation (FST=0.115–0.531) in some pairwise comparisons suggesting limited gene flow and independent evolution of some refugial populations. In L. sukaczewii, low levels of differentiation were found among populations from areas glaciated during the Pleistocene, indicating their recent origin. Our results also suggest these populations were created by migrants from multiple, genetically distinct refugia. Furthermore, some haplotypes observed in populations from previously glaciated areas were not found in putative refugial populations, suggesting these populations might have contributed little to the extant populations created after the Last Glacial Maximum. Some authors regard L. sukaczewii and L. sibirica as a single species, while others consider them as separate species. The observed conspicuous differences in haplotype composition and distribution between L. sukaczewii and L. sibirica, together with high values of FST between populations of the two species, appear to support the latter classification.

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