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  • 401.
    Sörman, Petra
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science.
    Klimatanpassningsplan och kostnads-nyttoanalys för Tullkammarkajen och Söder: Inriktning högre temperaturer, ökad nederbörd och stigande havsnivåer2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    "Land that is or may be inappropriate, regarding the residents' health and safety or the risk of flooding, erosion and accidents is great, no settlement should be planned or built. An increased awareness in planning for a future climate change develops the city's adaptability, making it less vulnerable and allows it to become a more robust society" (Halmstads översiktsplan 2030).

    Considering how the world and local society is developing, Halmstad will in the near future experience temperature rise, increased rainfall and rising sea levels. For a large coastal municipality like Halmstad, it is required that the municipality adapt to these challenges and take the necessary measures in good time. The consequences can be devastating if adaptation is not done for a changed future climate.

    Halmstad has two areas in the city that require further analysis, these are Tullkammarkajen and Söder. Tullkammarkajen is a planned residential area, that will be built in 2020 and Söder is an area that is largely already built. Both areas are located directly next to Nissan, which floods when the water level rises above approximately +2.0 meter above sea level(masl). Today the city can count on extreme levels of +2.5 masl and the autumnstorm Gorm (2015) advised a water level of +2.37 masl. Forecasts from SMHI indicate that the sea level will increase one meter by 2100. At the same time the recurrence times for the water level of +2.5 masl will be reduced from about 50 years to only 2 years until year 2100.

    The temperature in Sweden will increase during this century and Halmstads average temperature will increase from 6-8°C to 10-14°C. The number of hot days increases from 10-15 to 50-55 days per year and heat waves during the summer will be much longer, with droughts, shortage of water and in worst case deaths as a result.

    The purpose of the report was to develop policy options for reducing the risk of floods and heat waves in Halmstad. The resources in the society are limited, therefore the most cost-effective adaptation is needed. The municipality currently has no knowledge of the most profitable options for reducing the impact of floods and heat waves, hence this report aims to investigate the matter.

    Method has been a flood simulation, 14 interviews, a literature review and an economic assessment by a cost-benefit analysis.

    Four different policy options, which reduce the risk of flooding and heatwaves, are listed in the report and investigate if the flood measures is economically profitable. They include increased vegetation,elevation, check valve, dykes, sluice gate and pumps.

    The assessment compares the benefits from the actions with the cost in an economic assessment. The analysis shows that despite high investment costs, all proposals for action are economically viable with a time horizon of 100 years.

  • 402.
    Thiere, G.
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Stadmark, J.
    Lund University.
    Weisner, Stefan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Retention capacity achievements versus climate gas emission by constructed agricultural wetlands2007In: 2nd International Symposium on Wetland Pollutant Dynamics and Control - WETPOL 2007: Extended abstracts / [ed] Ülo Mander, Margit Kõiv, Christina Vohla, Institute of Geography, University of Tartu , 2007, p. 302-304Conference paper (Other academic)
  • 403.
    Thiere, Geraldine
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Biodiversity and ecosystem functioning in created agricultural wetlands2009Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This doctoral dissertation was produced in a cooperation between Halmstad University (Wetland Research Centre, School of Business and Engineering) and Lund University (Limnology & Marine Biology, Department of Ecology).

    Abstract . Wetland creation at large, regional scales is implemented as a measure to abate the biodiversity loss in agricultural landscapes and the eutrophication of watersheds and coastal areas by non-point source nutrient pollution (mainly nitrogen). The consequences of creating many new wetlands for biodiversity conservation and nutrient reten- tion (ecosystem functioning) in agricultural landscapes are still relatively unknown, both on local (per wetland) and regional (per landscape) scales. In Sweden, wetland creation has progressed already since the 1990s, and by now larger numbers of created wetlands are present, mainly in the intensively farmed landscapes of southwestern Sweden. This thesis aimed to investigate the following aspects in these systems: (i) their large-scale effects on biodiversity, (ii) their functional diversity of bacterial denitrifiers, (iii) the abiotic and biotic influences on wetland ecosystem functioning, (iv) the potential for biodiversity-function links, and (v) the potential for functional links and joint functioning.(i) Created wetlands hosted diverse assemblages of macroinvertebrates and plants. They maintained a similar com- position and diversity as natural ponds in agricultural landscapes. The environmental conditions per wetland did hardly affect macroinvertebrate and plant assemblages, and the prerequisites for nutrient retention did neither. In landscapes were wetland creation efforts had increased the total density of small water bodies by more than 30%, macroinver- tebrate diversity of created wetlands was facilitated on both local and regional scales. (ii) Diverse communities of denitrifying bacteria with the capacity for conducting different denitrification steps (functional types) were present in all investigated wetlands. The richness of denitrifying bacteria communities was affected by nitrate concentration and hydraulic loading rate, which may potentially be relevant for the nitrogen retention function of created wetlands. The diversity across different functional types of bacterial denitrifiers increased with nitrate concentration. (iii) Both abiotic and biotic factors influenced ecosystem functions of created wetlands. Variation in nitrogen retention was associated to nitrate load, but even to vegetation parameters. In wetlands with constant nitrate load, planted emergent vegetation facilitated nitrogen retention compared to other vegetation types. In wetlands with variable loads, nitrogen retention was facilitated if nitrate load was high and many different vegetation types were present; nitrogen load could explain the majority of the variation in nitrogen retention compared to vegetation parameters. Phosporus retention of created wetlands was best explained by vegetation parameters. Litter decomposition was inhibited at high nitrate to phosphorus ratios. Methane production increased with age and decreased with plant cover. (iv) Biodiversity may facilitate wetland ecosystem functions, particularly in dynamic wetland ecosystems. Nitrogen retention increased with vegetation type diversity, phosphorus retention capacity with plant richness, and litter decomposition with macroinvertebrate diversity. (v) Created wetlands have the capacity of sustaining several parallel ecosystem services. Some wetland functions were coupled; nitrogen retention increased with fast litter decomposition. On the other hand, methane emission and nitro- gen retention were independent of each other, as were nitrogen and phosphorus retention.In conclusion, created wetlands have the potential to at least partly abate the lost biodiversity and multifunctionality caused by the past extensive destruction of natural wetlands in agricultural landscapes.

  • 404.
    Thiere, Geraldine
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Milenkovski, Susann
    Department of Ecology, Ecology Building, Lund University, Lund, Sweden.
    Lindgren, Per-Eric
    Department of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.
    Sahlén, Göran
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Berglund, Olof
    Department of Ecology, Ecology Building, Lund University, Lund, Sweden.
    Weisner, Stefan E.B.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Wetland creation in agricultural landscapes: Biodiversity benefits on local and regional scales2009In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 142, no 5, p. 964-973Article in journal (Refereed)
    Abstract [en]

    Wetland creation aiming at a simultaneous increase in nutrient retention and species diversity in agricultural landscapes has recently become applied as a catchment-scale compensation measure for past wetland losses. Here, we evaluate if, and to what extend, dual-purpose wetlands benefit local and regional diversity of agricultural landscapes. We analysed composition and α, β, and γ diversity of aquatic macroinvertebrate assemblages among dual-purpose wetlands in an agricultural region in southwest Sweden in relation to local (water quality, wetland morphology, succession stage, proximity to other aquatic habitats) and landscape parameters (regional connectivity, wetland density). Diversity of mature agricultural ponds was used as a standard to evaluate the value of dual-purpose wetlands. Dual-purpose wetlands sustained α, β, and γ diversity similar to that of natural lentic water bodies in agricultural landscapes in the region and elsewhere. Over 80% of the overall species richness was attributed to β diversity, and each created wetland contributed to overall species accumulation. Ecosystem parameters explained 19% of the compositional variation among assemblages, but were only marginally related to diversity. Wetland density promoted α and γ diversity, while spatial heterogeneity (β) remained equally high, independent of wetland density. Our results indicate that catchment-scale wetland creation for simultaneous retention and diversity purposes benefits the biodiversity of agricultural landscapes, particularly if the density of aquatic habitats is increased by at least 30%.

  • 405.
    Thiere, Geraldine
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Schulz, Ralf
    Department of Zoology, University of Stellenbosch, South Africa.
    Runoff simulation with particle-associated azinphosmethyl in multispecies stream microcosms: implications for the field2004In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 23, no 8, p. 1984-1990Article in journal (Refereed)
    Abstract [en]

    We investigated the acute (5 d) effects of particle-associated azinphosmethyl (AZP) in multispecies microcosms and assessed the results in the context to data obtained from a parallel field study undertaken in the Lourens River, South Africa. A runoff simulation was carried out in stream microcosms containing the macroinvertebrate fauna of an uncontaminated Lourens River site exposed to particle-associated AZP (control and 200, 1,000, 5,000, 20,000 μg/kg; three replicates each) for 1 h. Measured AZP concentrations in filtered microcosm water resulted in the following values: Not detectable (control) and 0.03, 0.2, 1.1, and 6.9 μg/L, respectively. The two highest treatments resulted in significantly (analysis of variance [ANOVA]) reduced total numbers of individuals, while the number of taxa was affected in the 20,000 μg/kg treatment only. A comparison with previous data suggests that observed effects partly resulted from particle-associated AZP. Particularly affected were six out of 14 macroinvertebrate taxa such as mayfly and stonefly taxa. In parallel, the distribution of macroinvertebrates at a pesticide-free and a contaminated stretch of the Lourens River was monitored five times during the spraying season in 2001 and 2002. Out of the 14 core taxa found in the microcosm study as well as in the field approach, 10 showed comparable reactions in the microcosm experiment and in their field distribution; they were either classified as affected or unaffected in both studies. Thus, we conclude that particle-associated AZP has the potential to affect the invertebrate community structure of the Lourens River and that microcosm studies employing field-relevant exposure scenarios may be valuable for a local risk assessment of pesticide-related community disruptions in the Lourens River.

  • 406.
    Thiere, Geraldine
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Schulz, Ralf
    Department of Zoology, University of Stellenbosch, South Africa .
    Runoff-related agricultural impact in relation to macroinvertebrate communities of the Lourens River, South Africa2004In: Water Research, ISSN 0043-1354, E-ISSN 1879-2448, Vol. 38, no 13, p. 3092-3102Article in journal (Refereed)
    Abstract [en]

    A field study at the Lourens River, South Africa, was undertaken during the pesticide application period between November 2001 and January 2002 in order to investigate the potential relation of agricultural pollution to the aquatic macroinvertebrate fauna. The upper regions of the Lourens River were free of contamination (LR1), whereas subsequent stretches flowing through a 400-ha orchard area (LR2) received transient insecticide peaks. Continuously operating suspended-particle samplers as well as flood samplers operating during runoff events were used to measure pesticide contamination. In addition, various physicochemical and morphological parameters were examined. A survey of the macroinvertebrate communities associated with the rocky substrates was carried out every three weeks. Community indices were calculated using the South African Scoring System (SASS 5) for bioassessment of water quality in rivers.

    The two sites differed in pesticide pollution as well as in average turbidity levels (LR1 5.5 mg/L; LR2 64.3 mg/L), but were similar in bottom substrate composition and most other abiotic factors. At the downstream site (LR2), pesticide values of 0.05 μg/L azinphos-methyl in water as well as 49 μg/kg azinphos-methyl, 94 μg/kg chlorpyrifos and 122 μg/kg total endosulfan in suspended particles were found during runoff conditions. The macroinvertebrate communities of the two sampling sites were similar in terms of number of total individuals, but differed significantly (ANOVA) in average number of taxa (LR1 11.7, LR2 8.9). Seven out of 17 investigated taxa occurred in significantly reduced numbers or were even absent at the downstream site LR2. The community characteristics determined by SASS 5 showed a significantly less sensitive community structure at the downstream site (TS 41; ASPT 4.6), indicating continuously lower water quality compared to site LR1 (TS 80; ASPT 6.9). It is concluded that the Lourens River macroinvertebrate communities are affected by agricultural pollution, with pesticides and increased turbidity as the most important stressors.

  • 407.
    Thiere, Geraldine
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Stadmark, Johanna
    Department of Ecology, Limnology, Lund University, Ecology Building, SE-223 62 Lund, Sweden.
    Weisner, Stefan E. B.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Nitrogen retention versus methane emission: Environmental benefits and risks of large-scale wetland creation2011In: Ecological Engineering: The Journal of Ecotechnology, ISSN 0925-8574, E-ISSN 1872-6992, Vol. 37, no 1, p. 6-15Article in journal (Refereed)
    Abstract [en]

    Coastal eutrophication by nutrient fluxes from agricultural land to marine recipients is presently combated by measures such as the implementation of watershed-scale wetland creation programs aimed at nitrogen removal. Such created agricultural wetlands – termed ‘nitrogen farming wetlands’ (NFWs) – receive nitrogen (N) loads predominantly as nitrate, facilitating N removal by denitrification. However, the conversion of agricultural soils into waterlogged wetland area is likely to increase climate gas emissions, particularly methane (CH4). There is thus a need to evaluate the benefits and risks of wetland creation at a large, watershed-scale. Here we investigate N retention and CH4 emission originating from watershed-scale wetland creation in South Sweden, the relation between both processes, and how CH4 emission depends on individual wetland parameters. We combine data from intensively studied reference wetlands with an extensive wetland survey to predict N retention and CH4 emission with simple models, to estimate the overall process rates (large-scale effects) as well as spatial variation among individual NFWs. We show that watershed-scale wetland creation serves targeted environmental objectives (N retention), and that CH4 emission is comparably low. Environmental benefit and risk of individual wetlands were not correlated, and may thus be managed independently. High cover of aquatic plants was the most important wetland property that suppressed CH4 net production, potentially facilitating N retention simultaneously. Further, differences between wetlands in water temperature and wetland age seemed to contribute to differences in CH4 net production. The nationally planned wetland creation (12,000 ha) could make a significant contribution to the targeted reduction of N fluxes (up to 27% of the Swedish environmental objective), at an environmental risk equaling 0.04% of the national anthropogenic climate gas emission.

  • 408.
    Thiere, Geraldine
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Weisner, Stefan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Biodiversity and ecosystem functioning in created agricultural wetlands.: Key note presentation.2009In: 3rd Wetland Pollutant Dynamics and Control - WETPOL2009- Barcelona / [ed] Josep M. Bayona & Joan García, 2009, p. 29-30Conference paper (Refereed)
  • 409.
    Thorén, Andreas Mygh
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    Effekter av funktionell träning och medicinbollkast för att optimera kinematic sequence och x-factor stretch i golfsvingen2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The interest for functional strength training in golf has grown the last decade and scientists are always trying to find training stategies to improve the biomechanical aspects of the swing. Kinematic sequence contains a proximal-to-distal sequence order towards impact, and an effective kinematic sequence in the down swing begins with a rotation in the pelvis and follows by an activation in thorax, arms and club in the respective order. The rotational torques in the proximal segments wanders through the body and to the more distal segments to create an effective energy – and power transfer at impact. The x-factor stretch is the seperation between the rotation in the pelvis and the thorax at the top of the back swing and at the beginning of the down swing. The kinematic sequence and x-factor stretch have been examined in recent studies and have established a correlation with club head speed, driving distance and accuracy. Although, studies have not found reliable training strategies for improving these aspects. The objectives of the study was to investigate if functional strength training and golf specific medicine ball throws for ten weeks could optimize a more effective kinematic sequence and increase the x-factor stretch among six elite amateur golfers. The medicine ball throw was performed by throwing the ball towards a visual ball placement on the ground and with an emphasis on power, and the functional strength training focused on dynamic stretching in thoracic spine and on pelvic – and core stability. The biomechanical data was collected by TPI 3D and were analyzed through mean values, standard deviations and student’s t-tests. The results showed significant improvements in the peak timing pre- impact of the club and in the pelvis, and also in the x-factor stretch. Improvements did also appear in peak speeds, acceleration and consistency within the group. Individual and significant differences could also be seen regarding timing, peak speed, acceleration, deceleration and angular speed gain between the segments. The study detected some distinct tendencies that could serve as a base for future studies. 

  • 410.
    Tonderski, Karin S.
    et al.
    IFM div. Ecology, Linkoping University.
    Svensson, J. M.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Ekstam, Börje
    Högskolan i Kalmar.
    Eriksson, Peder
    Länsstyrelsen i Örebro län.
    Fleischer, Siegfried
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Herrmann, Jan
    Högskolan i Kalmar.
    Sahlén, Göran
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Weisner, Stefan E.B.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Våtmarker: Närsaltsfällor och/eller myllrande mångfald?2003In: Vatten: tidskrift för vattenvård, ISSN 0042-2886, Vol. 59, no 4, p. 259-270Article in journal (Refereed)
    Abstract [en]

    This paper summarizes the state-of-the-art with respect to wetlands for nutrient removal and biodiversity enhancement, as expressed at a research workshop in December 2002. In the end of 2002, 260 and 884 wetlands had been constructed in Sweden with subsidies from LIP and the European Union, respectively. Most frequently, the aims were to remove nutrients from water and enhance biodiversity. The question raised is if we know how to design multifunctional wetlands. Should a wetland be deep or shallow, with or without macrophytes to be an efficient nutrient sink? Diverging opinions are presented, but generally it appears that fairly shallow wetlands at least partly covered by emergent macrophytes are favourable. The importance of extreme high flows and hydraulic short-circuiting is highlighted, and Danish and Norwegian approaches to wetlands construction are presented. Also, there is a risk that nutrient retaining wetlands develop a fairly trivial flora and fauna unless special care is taken. Intentional establishment of desirable and less common species, as well as creation of a variation of depth gradients to favour such species are such measures. Others are allowing for water level variations, as well as vegetation management such as grazing and harvesting.

  • 411.
    Tonderski, Karin
    et al.
    Department of Physics and Measurement Technology, Biology and Chemstry, Linköping University.
    Weisner, Stefan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Ecological biotechnology in wetlands?2004In: Water research – what’s next? / [ed] Birgitta Johansson, Stockholm: Forskningsrådet Formas , 2004, p. 41-43Chapter in book (Other academic)
  • 412.
    Tonderski, Karin
    et al.
    IFM, Linköpings Universitet.
    Weisner, Stefan E. B.Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.Landin, JanIFM, Linköpings Universitet.Oscarsson, HansMiljöskyddsenheten, Länsstyrelsen Västra Götaland.
    Våtmarksboken: Skapande och nyttjande av värdefulla våtmarker2002Collection (editor) (Other (popular science, discussion, etc.))
  • 413.
    Troast, Daniel
    et al.
    Department of Biology, Rutgers University, Newark, New Jersey, United States of America.
    Suhling, Frank
    Institut für Geoökologie, Technische Universität Braunschweig, Braunschweig, Germany.
    Jinguji, Hiroshi
    School of Food, Agricultural and Environmental Sciences, Miyagi University, Miyagi, Japan.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Ware, Jessica
    Department of Biology, Rutgers University, Newark, New Jersey, United States of America.
    A Global Population Genetic Study of Pantala flavescens2016In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 11, no 3, article id e0148949Article in journal (Refereed)
    Abstract [en]

    Among terrestrial arthropods, the dragonfly species Pantala flavescens is remarkable due to their nearly global distribution and extensive migratory ranges; the largest of any known insect. Capable of migrating across oceans, the potential for high rates of gene flow among geographically distant populations is significant. It has been hypothesized that P. flavescens may be a global panmictic population but no sufficient genetic evidence has been collected thus far. Through a population genetic analysis of P. flavescens samples from North America, South America, and Asia, the current study aimed to examine the extent at which gene flow is occurring on a global scale and discusses the implications of the genetic patterns we uncovered on population structure and genetic diversity of the species. This was accomplished using PCR-amplified cytochrome oxidase one (CO1) mitochondrial DNA data to reconstruct phylogenetic trees, a haplotype network, and perform molecular variance analyses. Our results suggested high rates of gene flow are occurring among all included geographic regions; providing the first significant evidence that Pantala flavescens should be considered a global panmictic population. © 2016 Troast et al.

  • 414.
    Turesson, Kristin
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science.
    Internationella och svenska erfarenheter av arbete med herrelösa katter2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
  • 415.
    Törngren, Lotta
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Skedala solcellspark2012Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    Skedala photovoltaic plant is the largest projected solar photovoltaic park in Sweden with

    4000 m2 and a total installed peak power of 610 kWp. The solar park planned for Halmstad

    Energy and Environment Ltd, which has a landfill in Skedala, a village northeast of Halmstad,

    where the final cover is in progress. When the final covering is finished, they want to use the

    land for something positive, which is good for both the environment and the residents? My

    work was to design and calculate the profitability of a photovoltaic power plant in the area. I

    chose to design the facility as a park, where you can get for a good time to play and snuggle

    up but also get knowledge about different types of solar cells. In the park, it will be possible

    to see the monocrystalline and polycrystalline solar cells, which are of solar type crystalline

    silicon and CIGS, that is a thin film cell. There are also variations though independent and

    mobile tracking system. HEM also considered, that it was important to get a clear picture of

    the environmental benefits of solar cells and therefore, calculations and comparisons are made

    in the case the electricity is used by households and electric cars compared to electricity made

    from coal and cars powered by petrol and diesel.

  • 416.
    Tønning, Kathe
    et al.
    Teknologisk institut, Danmark.
    Pedersen, Eva
    Teknologisk institut, Danmark.
    Drøjdahl Lomholt, Anette
    Teknologisk institut, Danmark.
    Malmgren-Hansen, Bjørn
    Teknologisk institut, Danmark.
    Woin, Per
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Møller, Lise
    Halmstad University, School of Business and Engineering (SET).
    Bernth, Nils
    Teknologisk institut, Danmark.
    Kortlægning og afgivelse samt sundhedsmæssig vurdering af kemiske stoffer i babyprodukter2008Report (Other (popular science, discussion, etc.))
    Abstract [en]

    Several baby products are intended to more or less to get in direct contact with baby skin or be in close contact to the skin. Moistening in the form of water, saliva, sweat or urine may cause that substances contained in the products, which can be released to these liquids, may get into contact with the skin or mouth of the baby. Besides uptake of chemical substances through the skin and from the baby sucking on the material exposure may also take place by inhaling of gasses slowly released/evaporating from the baby product of dusty particles and fibres released during use. The products included in the examination are primarily baby products intended for at children at the age of 0 to 1 year. Baby products have been deliberately selected that based on information from retailers are sold to a reasonable extent. The project primarily concerned products of textile or plastic with an upholstery or padding. In addition also baby products of flexible foam material were included. Baby clothing, bed linen (bolster case), shaped plastic objects (bath tubs, chamber pots, comforters, and baby plates), baby cutlery, and toys, wooden beds (cots) and baby care agents/remedies were not included in the project.

  • 417.
    Verikas, Antanas
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), CAISR - Center for Applied Intelligent Systems Research. Kaunas University of Technology, Kaunas, Lithuania.
    Vaiciukynas, Evaldas
    Kaunas University of Technology, Kaunas, Lithuania.
    Gelzinis, Adas
    Kaunas University of Technology, Kaunas, Lithuania.
    Parker, James
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Olsson, M. Charlotte
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Electromyographic Patterns during Golf Swing: Activation Sequence Profiling and Prediction of Shot Effectiveness2016In: Sensors, ISSN 1424-8220, E-ISSN 1424-8220, Vol. 16, no 4, article id 592Article in journal (Refereed)
    Abstract [en]

    This study analyzes muscle activity, recorded in an eight-channel electromyographic (EMG) signal stream, during the golf swing using a 7-iron club and exploits information extracted from EMG dynamics to predict the success of the resulting shot. Muscles of the arm and shoulder on both the left and right sides, namely flexor carpi radialis, extensor digitorum communis, rhomboideus and trapezius, are considered for 15 golf players (∼5 shots each). The method using Gaussian filtering is outlined for EMG onset time estimation in each channel and activation sequence profiling. Shots of each player revealed a persistent pattern of muscle activation. Profiles were plotted and insights with respect to player effectiveness were provided. Inspection of EMG dynamics revealed a pair of highest peaks in each channel as the hallmark of golf swing, and a custom application of peak detection for automatic extraction of swing segment was introduced. Various EMG features, encompassing 22 feature sets, were constructed. Feature sets were used individually and also in decision-level fusion for the prediction of shot effectiveness. The prediction of the target attribute, such as club head speed or ball carry distance, was investigated using random forest as the learner in detection and regression tasks. Detection evaluates the personal effectiveness of a shot with respect to the player-specific average, whereas regression estimates the value of target attribute, using EMG features as predictors. Fusion after decision optimization provided the best results: the equal error rate in detection was 24.3% for the speed and 31.7% for the distance; the mean absolute percentage error in regression was 3.2% for the speed and 6.4% for the distance. Proposed EMG feature sets were found to be useful, especially when used in combination. Rankings of feature sets indicated statistics for muscle activity in both the left and right body sides, correlation-based analysis of EMG dynamics and features derived from the properties of two highest peaks as important predictors of personal shot effectiveness. Activation sequence profiles helped in analyzing muscle orchestration during golf shot, exposing a specific avalanche pattern, but data from more players are needed for stronger conclusions. Results demonstrate that information arising from an EMG signal stream is useful for predicting golf shot success, in terms of club head speed and ball carry distance, with acceptable accuracy. Surface EMG data, collected with a goal to automatically evaluate golf player’s performance, enables wearable computing in the field of ambient intelligence and has potential to enhance exercising of a long carry distance drive.

  • 418.
    Vretare Strand, Viveka
    et al.
    Limnology, Department of Ecology, Lund University, Sweden.
    Weisner, Stefan E.B.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Interactive effects of pressurized ventilation, water depth and substrate conditions on Phragmites australis2002In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 131, no 4, p. 490-497Article in journal (Refereed)
    Abstract [en]

    Pressurized ventilation acts to increase the oxygen supply to roots and rhizomes in some species of emergent plants. In a greenhouse experiment, we investigated how pressurized ventilation affected growth, biomass allocation and mineral content of Phragmites australis in two water depths (15 cm or 75 cm) and two substrates (organic sediment or sand). Through perforating each stem above the water surface, pressurized ventilation was inhibited without affecting oxygen diffusion. In controls, 10-20% of the stems were perforated to make certain that lack of efflux sites would not limit pressurized ventilation. Plants with inhibited pressurized ventilation had lower oxygen concentrations in their stem bases than control plants. Growth was lower in plants with inhibited pressurized ventilation compared to controls except when plants grew in a combination of sand and shallow water. In plants grown in an organic sediment, but not in those grown in sand, inhibition of pressurized ventilation resulted in decreased biomass allocation to soil roots but increased allocation to aquatic roots. Stem perforation affected the tissue concentrations of nitrogen, phosphorus, magnesium, manganese and aluminium but not of calcium or iron. We suggest that the lower growth in plants with inhibited pressurized ventilation was caused by decreased mineral uptake, which may have resulted from the decreased proportional allocation to soil root weight, from decreased mineral availability or from impaired root function. In plants grown in sand in shallow water, diffusion seemed to cover the oxygen demand, as pressurized ventilation did not affect growth.

  • 419.
    Vårdal, Hege
    et al.
    Department of Systematic Zoology, Evolutionary Biology Centre, Uppsala University, Sweden.
    Sahlén, Göran
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Ronquist, Fredrik
    Department of Systematic Zoology, Evolutionary Biology Centre, Uppsala University, Sweden.
    Morphology and evolution of the cynipoid egg (Hymenoptera)2003In: Zoological Journal of the Linnean Society, ISSN 0024-4082, E-ISSN 1096-3642, Vol. 139, no 2, p. 247-260Article in journal (Refereed)
    Abstract [en]

    We describe gross egg morphology and provide the first data on eggshell ultrastructure in cynipoids (Hymenoptera) based on species representing three distinctly different life histories: internal parasitoids of endopterygote larvae, gall inducers and phytophagous inquilines (guests in galls). We then use existing phylogenetic hypotheses to identify putative changes in egg structure associated with evolutionary life-history transitions. We find four major structural changes associated with the shift from parasitoids laying their eggs inside a host larva to gall inducers laying their eggs in or on plants: (1) from a narrow and gradually tapering gross form to a distinct division into a stout body and a long and thin stalk; (2) from a thin to a thick eggshell; (3) from a flexible to a rigid endochorion; and (4) from crystal bundles with shifting orientation in the exochorion to layers of parallel crystal rods. By contrast, we find no major changes in egg structure associated with the transition from gall inducers to inquilines. Comparison between pre- and post-oviposition eggs of one gall inducer and one inquiline suggests that mechanical stress during the passage through the egg canal gives rise to numerous tiny stress fractures in the boundary separating the exo- and endochorion. In one of the gall inducers, Diplolepis rosae, that end of the egg, which is inserted into the plant, has a specialized and apparently porous shell that may permit chemical exchange between the embryo and the plant. Other structures that could facilitate chemical communication with the host plant through the eggshell were, however, not observed in the eggs of gall inhabitants.

  • 420.
    Waara, Sylvia
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Dagvattnets sammansättning i Västerås stad - En kunskapssammanställning2010Report (Other academic)
  • 421.
    Waara, Sylvia
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Landfill Leachate Ecotoxicity2013In: Encyclopedia of Aquatic Ecotoxicology / [ed] Jean-François Férard & Christian Blaise, Dordrecht: Springer, 2013, p. 649-670Chapter in book (Refereed)
  • 422.
    Waara, Sylvia
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Bandaruk, Tatsiana
    Halmstad University, School of Business and Engineering (SET).
    Metal and Metalloid Sequestration in a Constructed Wetland System for Treatment of Landfill Leachate During 2003–20122014Conference paper (Other academic)
    Abstract [en]

    The treatment of landfill leachate in constructed wetland systems is a common practice in Europe. However, very few studies were made to evaluate their performance over a long period of time. A free surface constructed wetland system consisting of sediment traps followed by 10 ponds connected with overflows was built at Atleverket near Örebro, Sweden in 2001. It receives pre-treated leachate from the municipal landfill. As part of the wetland monitoring programme a large data set on the surface concentrations of 15 metals and 2 metalloids has been collected from different sampling sites within the wetland during the operation period. In this study, the data from inlet and outlet of the wetland were compiled and analysed. The aim of this paper is therefore to estimate the removal efficiency of metals and metalloids using data on concentrations and flow and investigate the effect of wetland age on removal pattern. The elements with the highest removal efficiency were Al, As, Ba, Ca, Cr, Cu, Fe, Mn, Pb, V and Zn ranging from 95% for Pb to 65 % for Ca. The elements with the lowest reduction were B, Co K, Mg, Ni and S ranging from Co 56 % to 40 % for S. It was found that the removal efficiency was not related to inlet concentrations of the elements as the elements with high and low inlet concentrations were found in both groups. Analysis of reduction pattern also revealed that the group with higher removal efficiency showed fairly constant outlet concentrations during the study period, while the elements with lower removal efficiency demonstrated variable outlet concentrations. No statistical difference in removal due to age of the wetland was found. The study results showed that the wetland system has high removal efficiency of metals and metalloids and the removal pattern is not affected by age of the wetland. The influence on reduction due to leachate characteristics, wetland design and retention time will be discussed.

  • 423.
    Waara, Sylvia
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Gajewska, Magdalena
    Gdańsk University of Technology, Gdańsk, Poland.
    Cruz Blázquez, Veronica
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Alsbro, Roland
    Eskilstuna Energi och Miljö AB, Eskilstuna, Sweden.
    Norwald, Pernilla
    Eskilstuna Energi och Miljö AB, Eskilstuna, Sweden.
    Waara, Karl-Otto
    Yderängen HB, Båstad, Sweden.
    Long term performance of an FWS wetland for post-tertiary treatment of sewage: the influence of flow, temperature and age on nitrogen removal2015In: Book of Abstracts: 6th International Symposium on Wetland Pollutant Dynamics and Control: Annual Conference of the Constructed Wetland Association: 13th to 18th September, 2015, York, United Kingdom / [ed] Gabriela Dotro & Vincent Gagnon, 2015, p. 38-39Conference paper (Other academic)
  • 424.
    Waara, Sylvia
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Gajewska, Magdalena
    Gdańsk University of Technology, Gdańsk, Poland.
    Dvarioniene, Jolanta
    Kaunas University of Technology, Kaunas, Lithuania.
    Ehde, Per Magnus
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Gajewski, Ryszard
    Gdańska Infrastructura Wodociągowo-Kanalizacyjna, Gdańsk, Poland.
    Grabowski, Pawel
    Grupa Lotos, Gdańsk, Poland.
    Hansson, Anna
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Kaszubowski, Jacek
    Gdańska Infrastructura Wodociągowo-Kanalizacyjna, Gdańsk, Poland.
    Obarska-Pempkowiak, Hanna
    Gdańsk University of Technology, Gdańsk, Poland.
    Przewlócka, Maria
    Gdańsk University of Technology, Gdańsk, Poland.
    Pilecki, Adam
    Grupa Lotos, Gdańsk, Poland.
    Nagórka-Kmiecik, Dagmara
    City Hall of Gdańsk, Environment Department , Gdańsk, Poland.
    Skarbek, Jacek
    Gdańska Infrastructura Wodociągowo-Kanalizacyjna, Gdańsk, Poland.
    Tonderski, Karin
    Linköping University, Linköping, Sweden.
    Weisner, Stefan
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Wojciechowska, Ewa
    Gdańsk University of Technology, Gdańsk, Poland.
    Towards Recommendations for Design of Wetlands for Post-Tertiary Treatment of Waste Water in the Baltic Sea Region – Gdańsk Case Study2014Conference paper (Other academic)
    Abstract [en]

    There are many challenges that need to be addressed if the far reaching objectives on high environmental status as required in the EU Water Framework Directive and the Marine Strategy Framework Directive will be met in the Baltic Sea Region within the next decade. For wastewater treatment plants (WWTP) this implies, in spite of the many improvements made during the last decade, development and introduction of new technology to further reduce eutrophying compounds, hazardous chemicals and pharmaceuticals. Constructed wetlands when properly designed and operated have been shown to be robust systems with low energy requirements that may not only reduce many types of pollutants but may also provide many additional ecosystem services beyond requirements generally imposed by authorities. For example, they may support and enhance biodiversity and be used to convert brownfield areas in urban landscapes to recreational areas. Reduced cost is possible if treated water is reused in industry or for irrigation. In a project, supported by the Swedish Institute, a group of scientists, a water company and water using industry has together with local authorities through workshops, field studies and literature studies worked on finding a general first recommendation on design and operation. In this paper we will present the scientific rational and legal constraints for the general design and operation of a wetland system for post-tertiary treatment of waste water from WWTPs using Gdańsk as an example. The proposal includes a first part, which mainly will be focusing on pollutant and pathogen removal using particle traps and a HSSF wetland on land owned by the WWTP and a second part consisting of a FWS wetland which, in addition to further polishing the water, will enhance biodiversity and provide recreational areas on derelict land owned by the city.

  • 425.
    Waara, Sylvia
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Khokhotva, Oleksandr
    National Technical University of Ukraine, Kyiv Polytechnic Institute, Kyiv, Ukraine.
    The effect of environmental conditions on the stability of heavy meltal-filter material complex as assessed by the leaching of adsorbed metal ions2011In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 159, p. 146-1463Article in journal (Refereed)
    Abstract [en]

    In this study the influence of environmental conditions, most likely prevailing in filter beds used for intermittently discharged pollutant streams such as landfill leachate and storm water, on the stability of the heavy metalefilter complex was investigated for 2 filter materials; non-treated and urea treated pine bark, using leaching experiments. The metalefilter complex stability was higher for urea treated than for non-treated pine bark and dependent on the metal adsorbed. The type of environmental condition applied was of less importance for the extent of leaching.

  • 426.
    Waara, Sylvia
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Wojciechowska, Eva
    Faculty of Civil & Environmental Engineering, Gdansk University of Technology, Gdansk, Polen.
    Distribution and removal efficiency of heavy metals in two constructed wetlands treating landfill leachate2011In: Water Science and Technology, ISSN 0273-1223, E-ISSN 1996-9732, Vol. 64, no 8, p. 1597-1606Article in journal (Refereed)
    Abstract [en]

    The results of heavy metals (Fe, Mn, Zn, Ni, Cu, Cr, Pb, Cd) removal and partitioning between aqueous and solid phases at two treatment wetlands (TWs) treating municipal landfill leachates are presented. One of the TWs is a surface flow facility consisting of 10 ponds. The other TW is a newly constructed pilot-scale facility consisting of three beds with alternately vertical and horizontal sub-surface flow. The metals concentrations were analysed in leachate (both TWs) and bottom sediments (surface flow TW). Very high (90.9-99.9%) removal rates of metals were observed in a mature surface flow TW. The effectiveness of metals removal in a newly constructed pilot-scale sub-surface flow wetland were considerably lower (range 0-73%). This is attributed to young age of the TW, different hydraulic conditions (sub-surface flow system with much shorter retention time, unoxic conditions) and presence of metallic complexes with refractory organic matter

  • 427.
    Wagstaffe, Jessica
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Anthropogenic impacts on an oligotrophic clear water lake in Halland, Sweden, assessed from two different data sets.2013Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Lake Skärsjön is a dimictic, oligotrophic, clear water lake with bottom plant communities including the rare Nostoc zetterstedtii. The lake is located in western Sweden, south of Gothenburg. During the late 1970s to mid-1980s, there was fish cage farming located near the outlet of the lake. When the fish farming was first introduced, there was concern over the health of the late which prompted a monitoring study which was conducted from 1980 to 1990 by the County Administration Board (regional governing body of Sweden). Starting in 1983, another National Monitoring study commenced simultaneously with the 10 year study. This monitoring study had one site taking measurements from 0.2-2m and collected the same data as the 10 year study.

    There were notable changes starting in 1985, the year the fish farming was closed down. After these changes, there are patterns indicating the lake returning to similar conditions before 1985. The pH of the lake is increasing and the acidity decreasing which reflects the ongoing decrease in atmospheric sulphur deposition and concentration in the lake.

    Overall, the impacts from the fish farming may have been more intense if it was located farther from the lake outlet. This would have allowed nutrient emissions from the fish cages to influence the lake more severely before exiting through the outlet. The lake is slowly recovering from this anthropogenic event and the current monitoring program, the National Monitoring study, should remain intact. 

  • 428.
    Wang, Liqian
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Different Pretreatments to Enhance Biogas Production: A comparison of thermal, chemical and ultrasonic methods2011Independent thesis Advanced level (degree of Master (One Year)), 30 credits / 45 HE creditsStudent thesis
  • 429.
    Ware, Jessica L.
    et al.
    Rutgers University, Newark, NJ, USA.
    Karlsson, Maria
    Lund University, Lund, Sweden.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Koch, Kamilla
    Johannes Gutenberg Universität Mainz, Mainz, Germany.
    Evolution of reproductive strategies in libellulid dragonflies (Odonata: Anisoptera)2012In: Organisms Diversity & Evolution, ISSN 1439-6092, E-ISSN 1618-1077, Vol. 12, no 3, p. 313-323Article in journal (Refereed)
    Abstract [en]

    In Libellulidae, oocyte production has been assumed to be continuous, with periods of egg-laying interspersed with periods of resting/eating; however, recent work suggests that two types of oocyte production are common: either (a) continuous or (b) step-wise. These are mirrored in the arrangement of the ovarioles in the ovaries. Likewise, two types of mate-guarding behavior have been observed in Libellulidae: (1) non–contact guarding and (2) tandem guarding in which the male either hovers above the female or is physically attached to her during oviposition. Using molecular (mitochondrial and nuclear) data we explored the evolution of female reproductive traits, focusing on ovariole morphology, as well as guarding behavior, in Libellulidae. Continuous egg production appears to have evolved more than once, as have tandem and non-contact guarding. We discuss how the evolution of different ovariole types and guarding behavior may have been influenced by habitat instability, dispersal and crowded oviposition sites; thus, migratory behavior or habitat availability may have been the driving force of ovariole evolution.

  • 430.
    Weisner, Stefan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Potential hos våtmarker anlagda för fosfor- och kväveretention i jordbrukslandskapet: analys och tolkning av mätresultat2012Report (Other academic)
  • 431.
    Weisner, Stefan
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Problems in determining the amounts of nutrients removed in wetlands created to abate run-off from agricultural fields without using excessively costly measurements2012In: Proceedings from the 7th SWS 2012 European chapter meeting: Wetland restoration – challenges and opportunities : Programme and abstracts, 17-21 June 2012 / [ed] Brian Kronvang, Carl Christian Hoffmann & Mirela Lăcrămioara Vlad, Aarhus: Aarhus University, DCE - Danish Centre for Environment and Energy , 2012, p. 53-53Conference paper (Other academic)
    Abstract [en]

    Creation of wetlands in the agricultural landscape has in Sweden been identified as a cost-effective way of decreasing nutrient transports to the Baltic Sea. Approximately 3,000 wetlands have been constructed so far in southern Sweden through different subsidy systems. The purpose is that these wetlands should counteract eutrophication by removing nitrogen and phosphorus while simultaneously contributing to increased biodiversity in the landscape.

    Continuous automatic (flow or time proportional) water sampling for nitrogen and phosphorus removal measurements were carried out in the inlet and outlet of 7 wetlands during 1.5 to 10 years. Strategic grab sampling, also in the inlet and outlet, was conducted in 14 wetlands during 2 years. Flow was measured only in the outlet in most wetlands. The wetlands were all located in agricultural areas and were chosen to represent wetlands with different nutrient loads from agricultural field run-off.

    Large temporal variations in water flows and concentrations complicated the interpretation of data. Analyses of the large dataset, in some cases comprising parallel measurements using different methods, showed that estimations of nutrients removal were, for example, sensitive to if short intensive inflows were adequately captured with the measurements or not. This led in particular to substantial underestimations of phosphorus removal.

    This suggests that removal rates or coefficients used in models to estimate the total amounts of nutrients removed from agricultural run-off in large-scale national programs for creating wetlands may be based on field measurements with severe shortcomings. National assessments may therefore have given misleading results and, at least for phosphorus, seriously underestimated the amount of removal that has been obtained. We need to find ways to accurately determine nutrient removal levels of a large amount of wetlands without using too costly measurements so that created wetlands retain their status as a cost-effective way to reduce nutrient transports from agriculture.

  • 432.
    Weisner, Stefan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Vilka faktorer styr kväveretentionen ianlagda våtmarker?: Resultat från experimentvåtmarker vid Plönninge2008Report (Other academic)
  • 433.
    Weisner, Stefan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Våtmarker i jordbrukslandskapet som åtgärd mot övergödning: kväveretention och  kostnadseffektivitet2008Report (Other academic)
  • 434.
    Weisner, Stefan E. B.
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Strand, John A.
    Rural economy and agricultural society, Lilla Böslid, Eldsberga.
    Ecology and management of plants in aquatic ecosystems2002In: Handbook of ecological restoration: Vol. 1, Principles of restoration / [ed] Martin R. Perrow, Anthony J. Davy, Cambridge: Cambridge University Press , 2002, p. 242-256Chapter in book (Refereed)
    Abstract [en]

    The central role of macrophytes for the functioning of aquatic systems means that the most effective way to manage these systems is often through vegetation management. For this we need to understand the mechanisms regulating vegetation distribution. Submerged macrophyte distribution is mainly related to water depth, water transparency and epiphytic growth. The distribution of emergent vegetation can largely be predicted from water depth and substrate characteristics. Also, in both submerged and emergent macrophytes, the effects on the vegetation of grazing can be dramatic. Management should aim at providing environmental conditions favouring the desired ecosystem state, rather than methods directly aimed at the vegetation. For example, the best method for promoting establishment of emergent vegetation is often lowering of the water level. To establish submerged vegetation, water transparency can be increased through biomanipulation (the removal of zooplanktivorous fish leading to increased zooplankton grazing pressure on phytoplankton). Changes in water depth and introduction of grazers are often effective measures to control growth of aquatic weeds.

  • 435.
    Weisner, Stefan E.B
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Bastviken Kallner, Sofia
    Department of Biology, Linköping University.
    Thiere, Geraldine
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Ehde, Per Magnus
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Tonderski, Karin S.
    Department of Biology, Linköping University.
    Influence of alternative states on nitrogen removal in experimental wetlands2007In: 2nd International Symposium on Wetland Pollutant Dynamics and Control - WETPOL 2007: extended abstracts / [ed] Mander Ülo, Koiv Margi, Vohla Chrisitna, Tartu: Institute of Geography, University of Tartu , 2007, p. 357-359Conference paper (Other academic)
    Abstract [en]

    Denitrification is the main process that remove nitrate from the water in wetlands. Plants can supply denitrifying bacteria with organic carbon and suitable attachment surfaces (Weisner et al. 1994). They also promote the development of anaerobic conditions through litter accumulation and decomposition, which would favour denitrification. The presence of plants has been shown to enhance nitrate removal in field studies (Bachand and Horne 2000). Toet et al. (2005) found a higher nitrogen removal in wetland compartments with emergent plants than with submersed plants. Results from microcosm studies have shown that the potential for denitrification is specific for different plant species (Bastviken et al. 2005).

    Wetlands may typically exist in alternative states, dominated by different kinds of vegetation. The purpose of this study was to investigate the effect of alternative state on nitrogen removal under controlled conditions in experimental wetlands.

  • 436.
    Weisner, Stefan E.B.
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Miao, Shi Li
    Everglades Department, South Florida Water Management District, West Palm Beach, USA .
    Use of morphological variability in Cladium jamaicense and Typha domingensis to understand vegetation changes in an Everglades marsh2004In: Aquatic Botany, ISSN 0304-3770, E-ISSN 1879-1522, Vol. 78, no 4, p. 319-335Article in journal (Refereed)
    Abstract [en]

    The northern Florida Everglades have experienced an expansion of cattail (Typha domingensis) and a decrease of sawgrass (Cladium jamaicense) communities. In this study, spatial and temporal within-species variability in plant performance were used to explore the mechanisms causing the distributional changes of cattail and sawgrass. Biomass, shoot density, plant weight, shoot height, and biomass allocation to different plant components (leaves, shoot bases, roots and rhizomes), were sampled in cattail and sawgrass stands along a nutrient gradient within water conservation area 2A during two sequential years with different water level conditions. The shoot height–leaf weight relationships were analysed with allometric methods. Sawgrass exhibited responses to nutrient limitation that resembled functional responses to deep water, indicating that impact of deep water was stronger when plant growth was limited by nutrient deficiency. In cattail, responses along the nutrient gradient were less pronounced. Plant responses along the nutrient gradient differed between years. This was most evident in sawgrass, showing that this species was more affected by water depth than cattail. Responses in sawgrass suggested that this species had to sacrifice important plant functions in deep water at low-nutrient sites. The results in this study emphasise that, to preserve and restore sawgrass communities, lower water levels are required. For cattail, a combination of low phosphorus availability and disturbances (such as extended droughts and outbreaks of herbivores) is needed to stop the ongoing expansion. Management of these ecosystems must consider the relative roles of water level, nutrient enrichment, and disturbances, for vegetation development.

  • 437.
    Weisner, Stefan E.B.
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Strand, John A.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Sahlén, Göran
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Thiere, Geraldine
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Ehde, Per Magnus
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Svensson, Jonas M.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Combating eutrophication and biodiversity loss in Sweden: importance of constructed wetlands in the agricultural landscape2007In: Multifunctions of wetland systems, Padua: PAN , 2007, p. 60-61Conference paper (Other academic)
    Abstract [en]

    The results of this evaluation show that constructed wetlands in the agricultural landscape are capable of a substantial reduction of the nutrient transport to downstream recipients, but only if properly located. These wetlands will also contribute to an increased biodiversity even if not planned primarily for this purpose. The use of wetlands for multiple functions needs to be developed to motivate large-scale wetland construction.

  • 438.
    Weisner, Stefan E.B.
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Thiere, Geraldine
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Effects of vegetation state on biodiversity and nitrogen retention in created wetlands: a test of the biodiversity–ecosystem functioning hypothesis2010In: Freshwater Biology, ISSN 0046-5070, E-ISSN 1365-2427, Vol. 55, no 2, p. 387-396Article in journal (Refereed)
    Abstract [en]

    1. Nitrogen retention in wetlands provides an example of an ecosystem function that is desired by human society, and is a rationale for the creation of wetlands to decrease nitrogen fluxes from nitrate-loaded river catchments to coastal waters.

    2. Here, we tested the impact of different vegetation states on species diversity and nitrogen retention during 4 years in surface-flow wetlands receiving nitrate-rich water. Tall emergent vegetation or submerged vegetation was introduced to six experimental wetlands each and six wetlands were left as unplanted controls for free development of vegetation. This resulted in three vegetation states dominated by emergent vegetation, by a mixture of submerged vegetation and filamentous green algae or by filamentous green algae.

    3. Species diversity (species richness and Shannon diversity) of plants was initially lowest in free development wetlands, but during the study became lower in the emergent vegetation wetlands than in the other wetlands. Diversity of macroinvertebrates was initially lower in the submerged vegetation wetlands than in the other wetlands, but this difference disappeared during the study. Nitrogen retention was consistently higher in emergent vegetation wetlands than in the other wetlands throughout the study.

    4. We conclude that plant diversity in wetlands dominated by tall emergent vegetation gradually became lower than in other wetlands, due to dominant species competitively excluding other plants. However, these wetlands were more efficient at removing nitrogen than those dominated by filamentous algae or submerged macrophytes.

    5. Management of wetlands often aims to decrease the dominance of tall emergent vegetation for the benefit of plant species diversity and habitat heterogeneity. Our results demonstrate a biodiversity benefit, but also show that this strategy may decrease the ability of wetlands to remove nitrogen. In this case, there is no support for the hypothesis that biodiversity enhances ecosystem function.

  • 439.
    Weisner, Stefan
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Johannesson, Karin
    Linköpings universitet, Linköping, Sverige.
    Tonderski, Karin
    Linköpings universitet, Linköping, Sverige.
    Näringsavskiljning i anlagda våtmarker i jordbruket: Analys av mätresultat och effekter av landsbygdsprogrammet2015Report (Other academic)
    Abstract [en]

    Measurements of removal of phosphorus and nitrogen in created wetlands in agricultural areas in Sweden have been compiled and analysed. The results indicate the level of phosphorus and nitrogen removal that can be achieved in created wetlands in agricultural areas in Sweden. The results have also been used to develop new models for calculating removal of phosphorus and nitrogen in created wetlands in which measurements have not been done. Finally, these models have been used to estimate the removal effects that can be expected in the wetlands that have received financial support within the Swedish Rural Develop­ ment Programme in 2007–2013, and how much the transport of phosphorus and nitrogen to the sea will decrease due to the creation of these wetlands.

    The new results show that phosphorus removal has been underestimated in earlier measurements as well as in models used in previous evaluations. In individual well designed and located wetlands, a removal of 100 kilo phosphorus and 1 000 kilo nitrogen per hectare wetland area and year can be obtained. The new results also indicate that it should be possible to achieve a removal of 50 kilo phosphorus and 500 kilo nitrogen per hectare wetland area and year in wetland creation programs prioritizing wetlands that are located and designed primarily for nutrient removal. The costs are estimated to 100 SEK per kilo phosphorus and 10 SEK per kilo nitrogen, if 50 percent of the costs are allocated to biodiversity and other ecosystem services.

    Model calculations based on a selection of representative wetlands within the Rural Development Programme were scaled up to the 5 261 hectare wetland area that have been granted financial support during 2007–2013. The evaluation show that the Rural Development Programme will result in a reduced transport to local waters­ heds of about 25 tons of phosphorus and 200 tons of nitrogen per year. Therefore, the transport to the sea will decrease with about 18 tons of phosphorus per year and about 170 tons of nitrogen per year, corresponding to 1.9 and 0.5 percent, respectively, of the transport to the sea from agricultural land.

    Creation of wetlands within the Rural Development Programme has thus resulted in significant decreases of transports of phosphorus and nitrogen to inland waters and the coastal sea. However, a comparison of removal per hectare wetland area and year between what has been achieved within the Rural Development Programme and in individual wetlands suggests that the effect could be substantially increased with a better location and design of wetlands.

  • 440.
    Weisner, Stefan
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Mietto, Anna
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Ehde, Per Magnus
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Persson, Jesper
    Swedish University of Agricultural Sciences, Alnarp, SWEDEN.
    Influence of vegetation on hydraulics in experimental surface-flow wetlands2009In: 3rd Wetland Pollutant Dynamics and Control - WETPOL 2009 - Barcelona / [ed] Josep M. Bayona & Joan García, 2009, p. 179-180Conference paper (Refereed)
  • 441.
    Weisner, Stefan
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Svensson, Jonas M.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Strand, John A.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Svengren, Henrik
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Combating eutrophication in Sweden: Importance of constructed wetlands in agricultural landscapes2005In: Is living water possible in agricultural areas?: Seminar on ecological engineering tools to combat diffuse pollution: June 20-22, 2005, Norway: Proceedings from NJF seminar no. 374 / [ed] Bent C. Braskerud, Ås, Norway: Jordforsk , 2005, p. 66-69Conference paper (Other academic)
    Abstract [en]

    The Wetland Centre at Halmstad University was commissioned by the Swedish Environmental Protection Agency and the Swedish Board of Agriculture to evaluate the effects of artificially created wetlands in Sweden between the years 1996 and 2002 with regard to nutrient retention and biodiversity. The creation of these wetlands has been financed either by Rural Development Support (RDS: Miva, Project support or Lmiva without Project support) or by Local Investment Programmes (LIP). The results are presented separately for the four different categories of constructed wetlands:

    • Constructed wetlands financed by LIP (Local Investment Programmes) (1998-2002).
    • Constructed wetlands financed by PS (Project Support) (2000-2002).
    • Constructed wetlands financed by Miva (Restoration and Establishment of Wetlands and Ponds on Arable land and Semi-natural Grazing land) (1996-1999).
    • Constructed wetlands financed by Lmiva (RDS wetlands that only get management support) (2000-2002).

    The main purpose of this study has been to evaluate the extent to which wetlands created by means of these different support systems have contributed to reduced eutrophication and increased biodiversity. The purpose has not been to evaluate individual wetlands but to give an overview of the differences in efficiency between the various support systems and, to some extent, the difference in results between various geographical regions within Sweden. It has therefore been necessary to include a large number of wetlands in the evaluation, which means that extensive field sampling in the individual wetlands has not been possible. The estimates concerning nutrient retention has therefore been based on modelling, and the biodiversity has been assessed by using dragonflies (Odonata) as indicator organisms.

    Information on 908 wetlands with a total area of 2860 hectares financed by RDS has been compiled and registered. In terms of area, these wetlands divide into 1815 ha financed by Miva, 920 ha financed by PS and 125 ha by Lmiva. In addition, 274 wetlands created by means of LIP, with a total area of 439 ha, have been registered. Field surveys and sampling has been conducted in more than 100 wetlands randomly selected from this register. It is mainly the results from these selected wetlands that are presented here.

  • 442.
    Weisner, Stefan
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Thiere, Geraldine
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Mindre fosfor och kväve från jordbrukslandskapet: Utvärdering av anlagda våtmarker inom miljö- och landsbygdsprogrammet och det nya landsbygdsprogrammet2010Report (Other academic)
  • 443.
    Weisner, Stefan
    et al.
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Tonderski, Karin
    Linköpings Universitet.
    Biomassa kan produceras och näring återvinnas: Ett framtidsperspektiv2002In: Våtmarksboken: Skapande och nyttjande av värdefulla våtmarker / [ed] Karin Tonderski , Stefan Weisner, Jan Landin, Hans Oscarsson, Göteborg: Vattenstrategiska forskningsprogrammet (VASTRA) , 2002, p. 123-134Chapter in book (Refereed)
  • 444.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energiteknik.
    District Heating and Cooling2013In: Reference Module in Earth Systems and Environmental Sciences / [ed] Scott A. Elias et al., Elsevier, 2013Chapter in book (Refereed)
    Abstract [en]

    District heating and cooling systems move heat in urban areas. Heat and cold are generated in central supply units by heat or cold recycling, renewables, or by direct heat or cold generation. The heat and cold demands should be concentrated in order to keep low distribution costs. District heating and cooling systems substitute ordinary primary energy supply for heating and cooling. Therefore, district heating and cooling increase both energy efficiency and decarbonisation in the global energy system. However, district heating and cooling is a highly underestimated energy efficiency and decarbonisation method in contemporary energy policy, both nationally and internationally.

  • 445.
    Werner, Sven
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    District Heating in Sweden – Achievements and challenges2010Conference paper (Other academic)
    Abstract [en]

    The Swedish district heating sector has achieved a strong position with a market share of 60% during 2008 in the heat market for buildings in the residential and service sectors. This position has been reached during the last 30 years without major use of combined heat and power (CHP) plants. The district heat has instead been generated from a basket of waste incineration, industrial surplus heat, biomass, and some fossil CHP. But during the recent years, the fossil CHP has been replaced by biomass CHP. The specific carbon dioxide emissions are now more than 80% lower than in other European cities and towns using natural gas and fuel oil to heat buildings. This paper gives a short overview of the development of the Swedish district heating sector with respect to market position, the CHP situation, the carbon dioxide emissions, and the additional social cost for district heating.

  • 446.
    Werner, Sven
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Energiteknik.
    Ecoheatcool: Gauging district energy's potential in Europe2007In: District Energy, ISSN 1007-6222, Vol. 93, no 2, p. 23-28Article in journal (Refereed)
  • 447.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    Energiförsörjning: En introduktion till vårt energisystem2016 (ed. 1)Book (Other academic)
    Abstract [sv]

    Boken beskriver inledningsvis de grundläggande energiprinciperna samt det tekniska energisystemets organisation och hur detta energisystem relaterar till andra över- och underordnade energisystem. Vidare behandlas mer ingående den energianvändning som det tekniska energisystemet ska tillgodose i byggnader, industrier och transporter. Vidare beskrivs miljöpåverkan, energihistorien och de nuvarande politiska målen för energisystemet kortfattat. Boken avslutas med trettio viktiga slutsatser, fjorton typiska anläggningar för energiomvandling, definitioner av de viktigaste energiglosorna och svaren till bokens 42 övningsuppgifter.

    Syftet med denna lärobok är att ge en inledande översikt över den nomenklatur med konventioner, uttryck, storheter, beteckningar och enheter som används inom energitekniken. Man kan därför uppfatta läroboken som en kommenterad glosbok. Inriktning och nivå på läroboken ligger mellan den grundläggande energifysiken och den mer praktiskt tillämpade energitekniken. En viktig grundkunskap för denna bok är gymnasiets fysik- och kemikurser. Med denna bok som grund kommer det bli enklare att förstå efterföljande mer detaljerade energitekniska kurser.

    Bokens målgrupp är universitets- och högskolestudenter som har valt en utbildning med energiteknisk inriktning.

  • 448.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    European District Heating Price Series2016Report (Other academic)
    Abstract [en]

    This project has been devoted to collection of long time series of national average district heating prices in Europe, since this information is neither collected by the International Energy Agency nor Eurostat.

    In all, relatively long time series of district heating prices have been identified in 23 European countries, of which 20 countries are currently members of the European Union. Additional countries were Iceland, Norway, and Switzerland. These annual average prices have been estimated according to three different methods. Data sources have primarily been various national sources as national statistical authorities. Secondarily, various international sources have been used, when national sources could not provide required information.

    The outputs from this price collection project consist of long time series of national average district heating prices until 2013 and the corresponding annual revenues and heat sales. In all, 560 annual average national district heating prices have been estimated.

    Five main conclusions have been identified concerning European district heating prices:

    1. Currently, very little aggregated information is available about district heating prices in various European countries. The purpose with this price collection has been to close this information gap.
    2. International energy price analysts have therefore excluded district heating prices from their analyses.
    3. Countries with high district heating prices during 2013 were Denmark, Slovak Republic, Germany, Norway, and Sweden.
    4. Countries with low district heating prices during 2013 were Iceland, Bulgaria, Switzerland, Hungary, and Poland.
    5. Countries with high proportions of district heating costs in the disposable incomes during 2013 were Slovak Republic, Lithuania, Latvia, and Estonia.

    Market analyses and further conclusions based on these estimated time series of national district heating prices will be published in another publication. Hence, no explanations for different price levels in various countries have be provided in this report. © 2016 ENERGIFORSK

  • 449.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science.
    European space cooling demands2016In: Energy, ISSN 0360-5442, E-ISSN 1873-6785, Vol. 110, p. 148-156Article in journal (Refereed)
    Abstract [en]

    Information about European space cooling demands is rare, since cooling demands are not properly measured, when electricity is used for operating space cooling devices. Cooling demands are only measured at deliveries from district cooling systems. However, information about cooling demands by location and country is required for planning district cooling systems and modelling national energy systems. In order to solve this cooling information dilemma, space cooling demands have been assessed for European service sector buildings. These estimations were based on cold deliveries from twenty different European district cooling locations in eight countries. Main findings are that (1) the estimated specific cold deliveries are somewhat lower than other estimations based on electricity inputs and assumed performance ratios, (2) aggregated spacecooling demands are presented by country, and (3) an European contour map is presented for average specific space cooling demands for service sector buildings. © 2015 Elsevier Ltd.

  • 450.
    Werner, Sven
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Energy Science. Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Fjärrvärmens framtida roll i Europa2017Report (Other academic)
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