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  • 51.
    Hedström, Ingemar
    et al.
    Boston University, College of Arts and Sciences, Boston, MA, United States.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    An extended description of the larva of Megaloprepus caerulatus from Costa Rica (Odonata: Pseudostigmatidae)2003In: International Journal of Odonatology, ISSN 1388-7890, Vol. 6, no 1, p. 23-31Article in journal (Refereed)
    Abstract [en]

    The larva of Megaloprepus caerulatus is described and illustrated from specimens collected near the northern border of Barbilla National Park on the Costa Rican Caribbean slope. Habits and characters of larvae of three different size classes obtained from artificial tree holes permit the identification of small (body length 4 mm, excluding the caudal lamellae) larvae up to the final stadium. New diagnostic characters include the shape of the prementum and head. © 2003 Taylor & Francis Group, LLC.

  • 52.
    Hedström, Ingemar
    et al.
    Boston University, Boston, USA.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    The dry season governs the reproduction of three pseudostigmatid zygopterans in Costa Rica: (Odonata Pseudostigmatidae)2007In: International Journal of Odonatology, ISSN 1388-7890, Vol. 10, no 1, p. 53-63Article in journal (Refereed)
    Abstract [en]

    The large Neotropical zygopterans Megaloprepus caerulatus, Mecistogaster linearis and M. ornata (Pesudostigmatidae) were surveyed during five years, and striking differences in their reproduction patterns were shown: (1) At two study sites in seasonal, tropical semi-dry forests in Pacific Costa Rica, adult M. ornata could be observed throughout the year, occasionally during the dry season up to 24 indivi duals at one time. Larvae were found from the middle to the end of the wet season suggesting a generation time of one year. (2) At two other study sites in aseasonal tropical wet forest in Caribbean Costa Rica, adults of M. caerulatus were observed year round, often in rather low numbers. Larvae of this species as well as M. linearis appeared throughout the year. While dry periods and rainfall certainly are key factors in governing the reproductive patterns of these species in relation to the climatic regimes of their preferred life zones, it is also concluded that competition from other container dwellers, including tadpoles of poison arrow frogs, may be additional factors in explaining their seasonal variation. It is also argued that all three species seem to have a high plasticity in their life cycles and hence are able to adapt to local conditions rather than displaying the same behaviour throughout their range.

  • 53.
    Hviid Nielsen, Torben
    et al.
    Centre for Technology and Culture, University of Oslo, Norway.
    Jelsøe, Erling
    Department of Environment, Technology and Social Studies, Roskilde University, Roskilde, Denmark.
    Öhman, Susanna
    Mid Sweden University, Östersund, Sweden.
    Traditional blue and modern green resistance2002In: Biotechnology: The Making of a Gobal Controversy / [ed] Martin W. Bauer & George Gaskell, Cambridge: Cambridge University Press, 2002, 1, p. 179-202Chapter in book (Other academic)
  • 54.
    Ivarsson, Felicia
    Halmstad University, School of Business, Engineering and Science.
    Naturvårdsarbete: Restaurering av landskap med hjälp av metoderna betning och bränning2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Grazing and burning are two natural disturbances that can be used as methods for restoring landscapes that have been damaged, either by man or by nature. In this study I have tried to figure out which of these methods are the best when it comes to restoration in landscapes. Do they work better together, on their own or should you just let the landscape be? My results showed that if you want high grass and a low coverage of bare ground, you should use the method of burning or just let the landscape be. If you want the opposite, low grass and a lot of bare ground, you should use the method of just grazing or use both grazing and burning. There is no right or wrong method because the best method is the one that helps you to reach the specific restoration goals. One thing to consider in this study is that the ecological interactions that happens between burning and grazing are often hard to study because they occur on such large scales. Therefore, you will only get a simplified understanding of these methods and the interactions between them when you perform this kind of study. Even if the results are simplified, I think that they can be very useful when influencing landscapes. They can guide you in the right direction, so that you can reach the goal you have with your restoration and also tell what method that won’t give a better result and thereby minimizing the workload.

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  • 55.
    Ivarsson, Sofia
    Halmstad University, School of Business, Engineering and Science.
    Invertebrate colonisation and diversity in constructed wetlands in Halland: A comparison between 2004 and 20062017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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  • 56.
    Jaggwe, Assad
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Effects of Environmental Variables on Four Aquatic Insect Taxa among Smaller Water Bodies of Different Ages on Farmland; A Pilot Study2015Independent thesis Advanced level (degree of Master (Two Years)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    High anthropogenic modification like infrastructural development, drainage, eutrophication, dumping garbage, is a threat to biodiversity of smaller water bodies in agricultural landscapes. However, smaller water bodies have historically been constructed for drainage, waste treatment and other purposes. Further, new small water bodies are now being constructed in agricultural areas in Sweden, mainly to remove nutrients and to improve landscape biodiversity. This creates two different age classes (old and new) of smaller water body habitats. I sampled aquatic insects in 27 smaller water bodies of varying types and ages in Halmstad region and related insect biodiversity, species richness, composition structure to environmental variables. I partitioned the region into two locations (Northern and Southern) for easy data comparison and due to difference in topography. The data was analysed using a Canonical Correspondence (CCA) and regression analysis. The CCA results show a difference in the species composition between old and new sites. The most important variables in explaining species assemblage structure was age of the aquatic water bodies. The species richness decreased with increase in nutrient concentration (total phosphorus) according to regression analysis. Species composition and diversity were related to Vegetation and tree cover in and around the water body. The results of my study shows that the older the water bodies the better for specific species like Aeshna cyanea and the new water bodies tolerate more specimens. My results suggest that, as there is need to facilitate plant growing, protecting vegetation and trees to better mimic natural conditions of water bodies, creating new water bodies while protecting aged water bodies is important for conservation of biodiversity.

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    Jaggwe
  • 57.
    Jakobs, Kristin
    Halmstad University, School of Business and Engineering (SET). Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Biomechanics and Biomedicine.
    ­Hur påverkar dietärt nitrat muskelfunktionen och återhämtningen vid styrketräning?: En pilotstudie i samarbete med Karolinska Institutet och Åstrands laboratoriet.2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Research on human physiology and how it is working is updated daily. In the world of sports they are testing new as old, natural as unnatural preparations and different training methods continuously in order to optimize athletic performance. A substance that´s been research on, up till today is nitric oxide and its influence in the body. From being interpreted as a harmful substance in the body, it went to possibly help heart disease patients, and also optimize the physic in sport performance. Nitric oxide is formed in the body naturally by oxygen, but it can also be formed without oxygen through the ingestion of nitrates found in many vegetables. Studies on nitrate in the sport field have concentrated on the effect on endurance sports and the effect has been shown to increase the efficiency and the blood flow to the muscles. Later on they also found that nitrate supplementation seems to give a lower Vo2max together with an increased time to exhaustion. These findings are really interesting because normally a reduction in Vo2max leads us to a decrease in workability. All these studies give an idea on how nitrate works aerobic, that is with oxygen. The research has not yet an explanation on how nitrate affect anaerobic work and maximum performance that occurs in weight training.

    The purpose of this study was to investigate how nitrate affects muscle function and endurance in strength training. In a randomized, double-blind, crossover trial, eight men (age 19-26, 23 (±2, 3)) consumed nitrate or a placebo (0.1 mmol/kg bodyweight/day) for three days. During the fourth day the test persons were tested in four different strength tests to see how they performed. Lactate and glucose concentrations were measured to see how the laktacid system was influenced.

    The study gave no support that dietary nitrate affects weight training. The results from the occasion with nitrate respectively placebo remained essentially unchanged.

    It was concluded that an intake of nitrate not will give any significant effects on the model of strength training. The main reason for this may be that nitrate provides the greatest impact on long-term work-duration and mainly during aerobic work. In this case the main use is mostly stored energy in the body, and the energy systems in which oxygen is required will probably not be of major importance.

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    FULLTEXT01
  • 58.
    Jarnemo, Anders
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS). Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agriculture, SLU, Riddarhyttan, Sweden.
    Jansson, Gunnar
    Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agriculture, SLU, Riddarhyttan, Sweden.
    Månsson, Johan
    Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agriculture, SLU, Riddarhyttan, Sweden.
    Temporal variations in activity patterns during rut - Implications for survey techniques of red deer, Cervus elaphus2017In: Wildlife research (East Melbourne), ISSN 1035-3712, E-ISSN 1448-5494, Vol. 44, no 2, p. 106-113Article in journal (Refereed)
    Abstract [en]

    Context Intraspecific differences in behaviour can affect censuses and bias population estimates, suggesting that choice and implementation of census methods are fundamental, and need to be adapted to behavioural variations. Aims We investigated temporal variations in activity patterns during the rut among red deer (Cervus elaphus) categories and the implications for two different census methods. Methods We used a long-term dataset collected during 17 consecutive red deer rutting seasons in southernmost Sweden. The two census methods were: (1) a collection of observation ratios; and (2) a count of individuals including identification of males. Both methods are commonly used in ungulate management. Key results There was a difference in activity among age and sex categories, with a temporal variation in activity and/or presence at rutting grounds of adult (≥6 years) and subadult (2-5 years) males. Observation ratios of adult and subadult males increased from low at the start of the rut to a top level during peak rut, with subadults lagging behind adults. Before and during peak rut, the proportion of adult males was higher than that of subadults. After peak rut, the proportion of adult males decreased, whereas subadult males remained high, resulting in a higher number of subadults than of adults. The comparison of the two census methods revealed a strong correlation regarding the trends of population size and for the age and sex categories. There was also a strong consistency concerning the calf/female ratio. The male proportion was, however, consistently lower in the collected observations than in the counts. Conclusions The lower proportion of males in observations compared with counts may be explained by behavioural differences among male age classes, i.e. by temporal variations in presence and activity. That females, calves and yearling males are stationary during the rut, but adult and subadult males arrive and depart the rutting grounds at varying points of time, can lead to an underestimated male proportion in continuously collected observation data. Implications The results suggest that census should be conducted during peak rut, and that incorporating identification of individual males in the monitoring may be beneficiary. © CSIRO 2017.

  • 59.
    Jarnemo, Anders
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS). Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agricultural Sciences, SE-730 91 Riddarhyttan, Sweden.
    Minderman, Jeroen
    Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, United Kingdom.
    Bunnefeld, Nils
    Biological and Environmental Sciences, University of Stirling, Stirling FK9 4LA, United Kingdom.
    Zidar, Josefina
    Department of Physics, Chemistry and Biology, Linköping University, SE-581 83 Linköping, Sweden.
    Månsson, Johan
    Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agricultural Sciences, SE-730 91 Riddarhyttan, Sweden.
    Managing landscapes for multiple objectives: Alternative forage can reduce the conflict between deer and forestry2014In: Ecosphere, ISSN 2150-8925, E-ISSN 2150-8925, Vol. 5, no 8Article in journal (Refereed)
    Abstract [en]

    Deer (Cervidae) cause considerable damage to forest plantations, crops, and protected habitats. The most common response to this damage is to implement strategies to lower population densities. However, lowering deer density may not always be desirable from hunting, recreational, or conservation perspectives. Therefore, knowledge is needed about additional factors beyond deer density that affect damage levels, and management actions that consider competing management goals. We studied the relationships between levels of bark-stripping by red deer (Cervus elaphus) on Norway spruce (Picea abies) and (1) relative deer density indices (pellet group count and deer harvest data), (2) availability of alternative natural forage (cover of forage species) and (3) proportion forest in the landscape, both at a forest stand scale and at a landscape scale. Extensive variation in damage level was evident between the six study areas. On a stand scale, the proportion of spruce damaged was positively related to pellet group density, indicating the importance of local deer usage of stands. In addition, available alternative forage in the field layer within spruce stands and proportion forest surrounding stands was negatively related to damage level. On the landscape scale, damage level was negatively related to availability of forage in the field and shrub layers and proportion forest, but was not related to any of the relative deer density indices. Increasing alternative forage may thus decrease damage and thereby reduce conflicts. Additionally, the proportion of forest in the landscape affects damage levels and should thus be considered in landscape planning and when forecasting damage risk. The relationship between local deer usage of stands and damage level suggests that future studies should try to separate the effects of local deer usage and deer density. © 2014 Jarnemo et al.

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  • 60.
    Jarving Ohlsson, Julius
    et al.
    Halmstad University, School of Business, Engineering and Science.
    Welander, Linus
    Halmstad University, School of Business, Engineering and Science.
    Hasslebäcken En studie av vattenkvalitet,vandringshinder och potentiellareproduktionsbiotoper för öring2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This paper is about analyzing water quality of a stream that flows in southwest of Swedencalled Hasslebäcken. The stream is a tributary of Suseån and has its springs in the naturereserve Biskopstorp and flows through a mixed landscape of mostly spruce forests andagriculture land. Little is known about Hasslebäcken and its water and therefore a study by request of Suseåns vattenråd was performed. The study consisted of analyzing the water ofphosphorous, nitrogen, pH, suspended particles and conductivity. To broaden the examination of water quality sampling of benthic macroinvertebrates and two index (ASPTindex and Shannon’s diversity index) of water quality were used. Another part of the study were to search for fish barrier in the stream and to evaluate the possibilities for troutspawning and habitats. The whole stretch of the stream were examined and eleven differentsampling sites were used. The results show that Hasslebäckens upper parts have low levelsof nutrients while the lower parts show intermediate to extremely high levels. The indexresults points at low ecological values for Shannon and high ecological values for ASPT. Thisis normal for a stream that flows through an agricultural landscape. The results concerning pH show a lower pH in the upper parts than in the lower parts. This is also normal for a stream in a production forest of spruce in these parts of Sweden. Hasslebäcken also have several fish barrier that prevent various fish species to migrate up along the stream from thesea. The evaluation of trout habitats and spawning area show decent possibilities for successful reproduction and growth.

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  • 61.
    Johannesson, Malin
    Halmstad University, School of Business and Engineering (SET).
    Prey choice of the snow leopard (Panthera uncia) in the Gobi desert in southern Mongolia.2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To properly plan a conservation strategy for large, elusive carnivores that lives in remote areas, there is a need for correct information about their diet. Problematically, endangered species such as the snow leopard are difficult to obtain information on, due to their camouflage, secretiveness and isolated lives in rugged ecosystems. Global positioning system (GPS) collars can thus provide useful information on snow leopard ecology and behavior. This study took place in the Gobi desert in southern Mongolia, and aimed to investigate the prey choices of the snow leopard. In total there were 19 snow leopards captured between 2008 and 2013 that were fitted with GPS collars. These collars registered a position every fifth to seventh hour. Kill sites were found by visiting clusters of GPS locations. Ibex was the prey most dominated (66 %), followed by goat, sheep (20 %), and argali (8 %). The ibex and argali were sex- and age-classified.  Age and sex ratio of the killed ibex differed from the age and sex ratio of the ibex population. Adult ibex males seemed to be overrepresented among the kills (males <5 years 10 % and males >5 years 35 %), whereas females seemed underrepresented. Also in argali, the category most killed were males (56 %). The results show that snow leopards do not only kill prey larger than themselves, they also seem to select the largest age and sex categories among ibex and argali, although the different categories killed varied between seasons. Possible explanations for the results are discussed. The findings of this study will help to understand the feeding ecology of the snow leopard, and how to address the conservation and management issues in how to conserve this felid and its most important preys.

  • 62.
    Johansson, Alfred
    Halmstad University, School of Business, Engineering and Science.
    Hållbar vattenkraft i Nissan: En förstudie och konsekvensutredning över förutsättningarna för ökade vandringsmöjligheter med nya fiskvägar.2015Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The hydropower from Nissan River is of national interest and produces annually 230 GWh from the twelve power stations in the main flow. For modified waters a consideration between the power production and the biological values has to be made. This reports serves as a pre-study for Nissans Vattenråd. It tries to evaluate some of the biological values in the Nissan basin and map the power production in the area. And the size and value of lost power production from new fishways for the twelve stations in the main flow.

    The investment of new fishways is calculated using simplified templates with values from the business. The cost and loss of power due to new fishways are calculated for three cases: fish friendly grates for the power station inlet and bypass for migration. Fish friendly grate and vertical-slot fish passage for migration. The last case is called “scenario” and is a combination with the most suited solution for each station. This includes a restoration of the creek, with maintained power production, for the two stations closest to the ocean.

    The cost for fish friendly grade and bypass for al stations is about 207 mskr and for vertical-slot fish passage 125 mskr. They both result in a loss of power production of 12 GWh/year, corresponding to a value of 3,2 mskr (NordSpot sale price only) annually. Case “scenario” costs 177 mskr and loses additionally 4,2 GWh/year.

    In the overview, large parts of the Nissan runoff has difficulties reaching “god ecological status” which is the goal set for 2021. This goal can be extended to 2027. The main problem is chemical effect of acidification and mercury in the ground, as well as connectivity issue caused by dams and culverts. Salmon and sea trout could earlier migrate to Nissafors and is limited to the lower parts of Nissan to Oskarström. Many of the tributary waters have high biological values. The existing fishways have questioned functionality and delays fish migration today. Before decisions are made about increasing fishways the advice is to do further studies about the breeding grounds. It’s also possible to identify positive cash flows from an increase in fish migration.

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    Hållbar Vattenkraft i Nissan
  • 63.
    Johansson, Andreas
    Halmstad University, School of Business, Engineering and Science.
    Återanslutning av s.k. korvsjöar till den ursprungliga flodfåran som en restaureringsåtgärd för ökad biodiversitet: -En litteraturstudie2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim with this review was to investigate whether a reconnection of an oxbow lake can contribute to higher biodiversity. However, oxbow lakes can be divided in three categories: Lentic- (connected with both ends to the river bed), semi-lentic- (connected with one end) and lotic oxbow lakes (Isolated from the riverbed). Aquatic organisms such as fish, aquatic invertebrates, amphibians and macrophytes has been studied. The result showed that hydrological connectivity determines both biodiversity and water quality in oxbow lakes. Lotic oxbow lakes consisted low biodiversity and it’s dominated by amphibians. Semi-lentic oxbow lakes contributes with highest biodiversity of macrophytes, fish and aquatic invertebrates. Lentic oxbow lakes consisted less biodiversity and was dominated by fish. In conclusion, reconnection of an oxbow lake can be used as a restoration project to improve biodiversity.   

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  • 64.
    Johansson, Emelie
    et al.
    Halmstad University, School of Education, Humanities and Social Science.
    Bergstaf, Sandra
    Halmstad University, School of Education, Humanities and Social Science.
    Mycket mer än bara ett begrepp: En litteraturstudie om lärares undervisningsmetoder för elevers naturvetenskapliga begreppsförståelse i årskurserna F-62018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Forskning visar att elever inte förstår innebörden av att lära sig naturvetenskap samtidigt som det framgår att ämnet är en naturlig del av människors vardag. Ämnet behöver därför göras förståeligt för att elever ska kunna verka som samhällsmedborgare. Naturvetenskap kan dock ses som svårt då det är ett abstrakt ämnesspråk som ofta uttrycks i naturvetenskapliga begrepp. Samtidigt som det framhålls att elever ska få stöd i sin språkutveckling har det visat sig vara svårt för lärare att göra naturvetenskapligt innehåll förståeligt för eleverna. Syftet med denna systematiska litteraturstudie är att undersöka och beskriva vad forskning säger har betydelse för att möjliggöra att elever i årskurserna F-6 erbjuds kunskaper i naturvetenskaplig undervisning. Mer precist vill vi besvara frågeställningen: Vilka undervisningsmetoder forskning belyser som användbara för lärare att använda för elevers begreppsförståelse inom de naturvetenskapliga områdena? Resultatet av litteraturstudien visar att utveckla pedagogisk innehållskunskap, guidad undervisning, synliggöra ämnets innehåll, ställa frågor och kommunicera naturvetenskap med olika sinnen är undervisningsmetoder som kan tillämpas i den naturvetenskapliga undervisningen för elevers begreppsförståelse. En slutsats blir dock att ingen undervisningsmetod kan appliceras utan en väl genomtänkt stöttning av lärare och att undervisningsmetoden utveckla pedagogisk innehållskunskap kontinuerligt bör utvecklas i takt med undervisningen. Utifrån de resultat som framkommit av litteraturstudien hade det varit intressant att genomföra icke-experimentella undersökningar om lärares undervisningsmetoder för elevers begreppsförståelse i naturvetenskap.

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  • 65. Johansson, Jessica
    et al.
    Rankinen, Juha
    Inventering av flodpärlmussla i Fylleån norr om Gyltigesjön2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Freshwater environments are threatened worldwide, of which many of the species associatedwith freshwater. In 2014, 243 freshwater mussels were on the international Red List. One ofthem is the freshwater pearl mussel, Margaritifera margaritifera, which because of itscomplex life cycle can be counted as an indicator of whether a stream is worth protecting. It's since the early 1900's in decline throughout their range. Sweden is counted as a core area which is why we have not only a national but an international responsibility to conserve the species. The mussel is covered by the County Administrative Board of Hallands action plans for threatened species. The County Administrative Board has since 2004 made a number of inventories in the county to get an overview of the occurrence of the freshwater pearl mussel. Still, there are some streams that are not fully inventoried. We have inventoried the mainstream Fylleån from outlet to Gyltigesjön to Bygget, as well as tributaries. In the 80's some parts further downstream in Fylleån were inventoried and then no freshwater pearl mussels were found. Per Ingvarsson who is leading the inventories of freshwater pearl mussels in Halland has pointed out the upper part as an interesting area for mussels. This upper part of Fylleån has previously only been inventoried on two locations, therefore, we have now done a complete inventory to examine the presence of mussels.

    Some of the results of our survey:

    • No fresh water pearl mussels were found in the investigated waters.

    • The water in the river was heavily colored which complicated the inventory.

    • The majority of the route consisted of flowing water with a bottom of stone and/or blocks which are suitable habitat for mussels, but there were silt on the bottom.

    • No fish or fish larvae were found.

    • One duck mussel was found in the outlet to Gyltigesjön.

    In closing, we discuss what could be causing our results.

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  • 66.
    Karlsson, Maria
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Koch, Kamilla
    University of Mainz.
    Continuous and stepwise oocyte production in Libellulidae (Anisoptera)2010In: Odonatologica, ISSN 0375-0183, Vol. 39, no 2, p. 107-119Article in journal (Refereed)
    Abstract [en]

    Compared to other insect groups, libellulids have a rather high mean number of ovarioles. In addition, the mean ovariole diameter differs greatly between and within species. In general, 2 different types of ovariole arrangement exist: (1) all developing oocytes mature and equal in size; in some species without, and in others with, surrounding connective tissue and (2) oocytes displaying gradual maturation, with only the outermost ovarioles mature. These differences have ecological consequences: the first arrangement occurs in spp. that have stepwise egg production. These spp. will lay one or more clutches, after which an interclutch interval of ovariole regrowth follows. Spp. with the second arrangement have continuous egg production and are able to lay at least some eggs all the time, reducing the length of interclutch intervals. However, no direct connection between mate-guarding strategies and ovariole arrangements can be seen. Nevertheless, it is believed that the process of ovariole maturation differs between these groups. It is concluded that ovary morphology in libellulids may exhibit evolutionary fixed traits, although the whole picture still remains complex. The ovariole arrangement may have a crucial impact on the reproductive ecology of the species.

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  • 67.
    Karlsson, Pauline
    Halmstad University.
    Anläggande av naturstig: ett sätt att främja intresset för och öka kunskapen om naturen2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    En naturstig utgörs vanligtvis av ett antal skyltar längst med en promenadslinga. Genom attgå stigen och ta del av texter och bilder får besökaren en flexibel form av guidning inaturområdet. Naturstigar är på det sättet ett bra sätt att locka ut människor i naturen. Ennaturstig kan bli forum för bland annat undervisning, rekreation och närturism. Stigarnaerbjuder en mer tillgänglig och tillrättalagd natur, som i vissa sammanhang är mer attraktivän den helt vilda.Som en del av mitt syfte har jag anlagt en naturstig vid Stadsbondgården i Fyllinge utanförHalmstad. I linje med syftet innehåller rapporten även forskning relaterat till ekoturism ochnaturstigar, för att kunna fungera som en metodvägledning för framtida anläggande avnaturstigar.Via mina skyltar ville jag uppmuntra till upptäckarlust, och ge naturstigsbesökaren enbegynnande eller fördjupad relation till naturen. Jag jobbade med en grundtanke om att visapå den rika biologiska mångfalden som även den stadsnära naturen besitter.En utvärdering av den färdiga stigen visade på brister i tydlighet och vägvisning. Innehålletpå skyltarna beskrevs av de flesta som positivt. Naturstigen uppfattades av en majoritet somvacker, lärorik och värd ett återbesök.

  • 68.
    Koch, Kamilla
    et al.
    Johannes Gutenberg Univ Mainz, Dept Ecol, D-55128 Mainz, Germany .
    Fuchs, Nadine
    Johannes Gutenberg Univ Mainz, Dept Ecol, D-55128 Mainz, Germany .
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Morphology of follicle cells of Libellulidae (Odonata)2011In: International journal of odonatology, ISSN 1388-7890, Vol. 14, no 3, p. 257-267Article in journal (Refereed)
    Abstract [en]

    In libellulids, mature oocyte size varies within and between individual ovaries. The regulating mechanism is not yet understood. Variations in the contents of the follicle cells, and thereby their ability to secrete material into the oocyte, might explain some of the observed differences in oocyte size. We therefore investigated the follicle cell surface, the interstitial space width between follicle cells and between follicle cells and oocytes, the number of nuclei, and the cell compartment proportions using scanning and transmission electron microscopy. In all investigated species, the follicle cells were covered by a basal lamina. We found cytoplasmic microvilli and septate junctions. As we could not find any pores or other structures on the cell surface, endocytosis seems to be the only mechanism transporting material into the follicle cells. Larger follicle cells had larger interstitial gaps between follicle cells and oocytes, larger nuclei and a larger mitochondrial area. Larger interstitial spaces between follicle cells and oocytes may afford more room that can be filled with material from the follicle cell layer. More mitochondria could provide more energy/ATP needed for the transport of the material. The quantity of free ribosomes and the mean number of nuclei seemed to be even more important to the productivity of the follicle cell. All these variations in cell contents cause productivity differences among follicle cells and may explain some of the size differences between oocytes within individual ovaries in libellulids.

  • 69.
    Koch, Kamilla
    et al.
    University of Mainz.
    Quast, Malte
    Waldweg 8, 38176, Wendeburg, Germany.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Morphological differences in the ovary of Libellulidae (Odonata)2009In: International Journal of Odonatology, ISSN 1388-7890, Vol. 12, no 1, p. 147-156Article in journal (Refereed)
    Abstract [en]

    All female Odonata have been assumed to produce oocytes continuously during their mature life span. However, a recent study of ovariole orientation and development led to the suggestion that Libellulidae are divided into two groups of species, one with continuous, the other with stepwise oocyte production. To find more evidence of this division, we compared the size variation and growth within the vitellarium of the ovary, studying oocytes, and follicle cells. We found that morphological characters discriminate between the two ovary types in eight of the 10 investigated species. In both types we found an increase in all measurements from the anterior to the posterior end of the vitellarium. The increase in oocyte width and follicle cell length was significantly higher in species with a continuous oocyte production. We also noted that follicle cells may have more than one nucleus and that their number can vary during vitellogenesis. Our study confirmed the hypotheses that two different ovary types exist in Libellulidae. The two species not fitting into this grouping could be an artefact of small samp le size due to intraspecific phenotypic plasticity, or else there might be more than two ovary groups, or even a continuum. We could not offer an explanation as to how the process of stepwise oocyte production differs from continuous based production on morphological characters.

  • 70.
    Koch, Kamilla
    et al.
    Department of Ecology, Johannes Gutenberg-University of Mainz, Mainz, Germany.
    Wagner, Christine
    Department of Ecology, Johannes Gutenberg-University of Mainz, Mainz, Germany.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Farmland versus forest: comparing changes in Odonata species composition in western and eastern Sweden2014In: Insect Conservation and Diversity, ISSN 1752-458X, E-ISSN 1752-4598, Vol. 7, no 1, p. 22-31Article in journal (Refereed)
    Abstract [en]

    1. Despite the loss of natural ecosystems in the developed world during the past millennia, anthropogenic landscapes still sustain much biodiversity. Our question was, whether ten year changes in regional Odonata faunas are comparable between farmland and forested areas, or if the species pool of farmland areas respond in other ways than that of forest.

    2. We used data of dragonfly larvae collected from 16 lakes in a farmland area in south-western Sweden in the years 2002 and 2011/12, and compared these to data from 34 lakes in a forest area in south-eastern Sweden in the years 1996 and 2006.

    3. The species-richness in the agricultural region increased by 17% but decreased by 13% in the forested region. The changes in occurrence and regional distribution were similar in both areas, affecting 71% and 69% of the species pool. Average extinction rates were comparable between the agricultural and the forested region (38% and 43%) while colonisation rates differed greatly (64% and 114%).

    4. The species composition differed between the regions; the forest lakes harboured a 29% larger species pool. It is possible that in the forested region, the regional species pool in areas surrounding the study sites could stabilise the extinction and have a positive effect on changes in species composition. We assume that the different habitat structures of the waters in the agricultural and the forest regions and changes in temperature are the main driving forces behind the shifts. The mean seasonal air temperature has increased by circa 0.5°C in both regions, when comparing ten-year periods before each sampling year.

  • 71.
    Kohli, Manpreet K
    et al.
    Department of Biological Sciences, Rutgers University-Newark, Newark, USA.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Kuhn, William R.
    Department of Electrical Engineering and Computer Science, University of Tennessee, Knoxville, USA.
    Ware, Jessica L.
    Department of Biological Sciences, Rutgers University-Newark, Newark, USA.
    Extremely low genetic diversity in a circumpolar dragonfly species, Somatochlora sahlbergi (Insecta: Odonata: Anisoptera)2018In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 8, p. 1-10, article id 15114Article in journal (Refereed)
    Abstract [en]

    We present the first empirical treatment of the northernmost breeding dragonfly, Somatochlora sahlbergi. We sequenced populations from United States, Canada, Finland, Sweden and Norway for cytochrome oxidase I (COI) and D2 region of 28s. We found that, despite geographic barriers across its vast arctic range, S. sahlbergi is a single species. Not only does it appear to interbreed across its entire range, there also seems to be almost no variation among European and North American populations in their COI gene fragment (the barcode gene), which is usually extremely variable. We further found that characters thought to be diagnostic for the larvae of S. sahlbergi were absent in our European samples. We review and re-describe the habitat of this species based on new findings from recent field observations. Finally, we report for the first time the likely presence of this species in Japan. We hope our findings will encourage further study of this species and other under-studied insect taxa that inhabit the remote Arctic.

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  • 72.
    Korkeamäki, Esa
    et al.
    Water and Environment Association of the River Kymi, Kouvola, Finland.
    Elo, Merja
    University of Jyväskylä, Jyväskylä, Finland.
    Sahlén, Göran
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Salmela, Jukka
    Regional Museum of Lapland, Rovaniemi, Finland.
    Suhonen, Jukka
    University of Turku, Turku, Finland.
    Regional variations in occupancy frequency distributions patterns between odonate assemblages in Fennoscandia2018In: Ecosphere, ISSN 2150-8925, E-ISSN 2150-8925, Vol. 9, no 4, article id e02192Article in journal (Refereed)
    Abstract [en]

    Odonate (damselfly and dragonfly) species richness and species occupancy frequency distributions (SOFD) were analysed in relation to geographical location in standing waters (lakes and ponds) in Fennoscandia, from southern Sweden to central Finland. In total, 46 dragonfly and damselfly species were recorded from 292 waterbodies. Species richness decreased to the north and increased with waterbody area in central Finland, but not in southern Finland or in Sweden. Species occupancy ranged from 1 up to 209 lakes and ponds. Over 50% of the species occurred in less than 10% of the waterbodies, although this proportion decreased to the north. In the southern lakes and ponds, none of the species occurred in all lakes, whereas in the north many species were present in all of the studied waterbodies. The dispersal ability of the species did not explain the observed species occupancy frequencies, but generalist species with a large geographical range occurred in a higher percentage of the waterbodies. At Fennoscandian scale, we found that the unimodal satellite pattern was predominant. However, at smaller scale, we found geographical variations in odonate species SOFD patterns. The most southern communities followed the unimodal satellite-dominant pattern, whereas in other regions communities fitted best with the bimodal core - satellite patterns. It seems that the richer species pool in the southern locations, and the larger distribution range of the northern species, skewed the unimodal pattern into a bimodal satellite dominant pattern. © 2018 The Authors.

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  • 73.
    Larsson, Matilda
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Ecology and Environmental Science.
    Inventering av Strandpadda (Bufo calamita) 2012 på Balgö och inom Varbergs kust2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
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    Examensarbete Bufo Calamita
  • 74.
    Levander, F.
    et al.
    Department of Protein Technology, Lund University, Lund, Sweden.
    Rögnvaldsson, Thorsteinn
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS).
    Samuelsson, J.
    Halmstad University, School of Information Science, Computer and Electrical Engineering (IDE).
    James, P.
    Department of Protein Technology, Lund University, Lund, Sweden.
    Automated methods for improved protein identification by peptide mass fingerprinting2004In: Proteomics, ISSN 1615-9853, E-ISSN 1615-9861, Vol. 4, no 9, p. 2594-2601Article in journal (Refereed)
    Abstract [en]

    In order to maximize protein identification by peptide mass fingerprinting noise peaks must be removed from spectra and recalibration is often required. The preprocessing of the spectra before database searching is essential but is time-consuming. Nevertheless, the optimal database search parameters often vary over a batch of samples. For high-throughput protein identification, these factors should be set automatically, with no or little human intervention. In the present work automated batch filtering and recalibration using a statistical filter is described. The filter is combined with multiple data searches that are performed automatically. We show that, using several hundred protein digests, protein identification rates could be more than doubled, compared to standard database searching. Furthermore, automated large-scale in-gel digestion of proteins with endoproteinase LysC, and matrix-assisted laser desorption/ionization-time of flight (MALDI-TOF) analysis, followed by subsequent trypsin digestion and MALDI-TOF analysis were performed. Several proteins could be identified only after digestion with one of the enzymes, and some less significant protein identifications were confirmed after digestion with the other enzyme. The results indicate that identification of especially small and low-abundance proteins could be significantly improved after sequential digestions with two enzymes.

  • 75.
    Lind, Linus
    Halmstad University, School of Business and Engineering (SET).
    Typhas inverkan på reningsgraden av TKN, BOD5 och COD i en anlagd rotzonsvåtmark i pilotskala.2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The ability for a subsurface flow constructed wetland system to treat landfill leachate was evaluated in Lajeado, Rio Grande do Sul, Brazil. Eight 0.95 m x 0.6 m experimental (SSF) units with a depth 0.4 m were used. Each wetland had unique conditions. Four units were planted with Typha angustifolia L. and four units were unplanted. Two different substrate dimension were used, four units with sand and four with gravel. Four wetlands operated in batch mode and four units with continuous flow. Batch flow systems were drained and filled up each week. To review vegetations impact on BOD5, COD and nitrogen compounds reduced in a wetland. This project lasted between January until May 2010 and samples were analyzed in April to May in four weeks.The result from this project show higher evapotranspiration water loss in units with planted vegetation and higher effluents concentration of BOD5, COD and nitrogen compounds, than in unplanted units.The ability for a subsurface flow constructed wetland system to treat landfill leachate was evaluated in Lajeado, Rio Grande do Sul, Brazil. Eight 0.95 m x 0.6 m experimental (SSF) units with a depth 0.4 m were used. Each wetland had unique conditions. Four units were planted with Typha angustifolia L. and four units were unplanted. Two different substrate dimension were used, four units with sand and four with gravel. Four wetlands operated in batch mode and four units with continuous flow. Batch flow systems were drained and filled up each week. To review vegetations impact on BOD5, COD and nitrogen compounds reduced in a wetland. This project lasted between January until May 2010 and samples were analyzed in April to May in four weeks.The result from this project show higher evapotranspiration water loss in units with planted vegetation and higher effluents concentration of BOD5, COD and nitrogen compounds, than in unplanted units.

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  • 76.
    Lindenfors, Patrik
    et al.
    Centre for the Study of Cultural Evolution, Stockholm University, Stockholm, Sweden.
    Jansson, Fredrik
    Centre for the Study of Cultural Evolution, Stockholm University, Stockholm, Sweden.
    Sandberg, Mikael
    Halmstad University, School of Education, Humanities and Social Science, Center for Social Analysis (CESAM), Centre for Studies of Political Science, Communication and Media (CPKM).
    The Cultural Evolution of Democracy: Saltational Changes in A Political Regime Landscape2011In: PLoS ONE, ISSN 1932-6203, E-ISSN 1932-6203, Vol. 6, no 11, article id e28270Article in journal (Refereed)
    Abstract [en]

    Transitions to democracy are most often considered the outcome of historical modernization processes. Socio-economic changes, such as increases in per capita GNP, education levels, urbanization and communication, have traditionally been found to be correlates or ‘requisites’ of democratic reform. However, transition times and the number of reform steps have not been studied comprehensively. Here we show that historically, transitions to democracy have mainly occurred through rapid leaps rather than slow and incremental transition steps, with a median time from autocracy to democracy of 2.4 years, and overnight in the reverse direction. Our results show that autocracy and democracy have acted as peaks in an evolutionary landscape of possible modes of institutional arrangements. Only scarcely have there been slow incremental transitions. We discuss our results in relation to the application of phylogenetic comparative methods in cultural evolution and point out that the evolving unit in this system is the institutional arrangement, not the individual country which is instead better regarded as the ‘host’ for the political system.

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  • 77.
    Lindstedt, Elenor
    Halmstad University, School of Business, Engineering and Science.
    Genetic variation between and within populations of Leucorrhinia dubia in Sweden, Finland and Norway2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Genom att extrahera, amplifiera och sekvensera DNA från ben av trollsländeartenLeucorrhinia dubia ämnar jag få en inblick i hur arter invandrat till Skandinavien sedan densenaste istiden och en mindre inblick i den genetiska variationen av arten i Skandinavien. Fördetta valdes en mitokondrisk gen (cytochrome c oxidase subunit I, COI) och en nukleär (28sribosomal RNA subunit D7). Totalt blev det 112 sekvenser (55 av COI genen och 57 för D7genen) från 10 olika populationer i Sverige, Norge och Finland som delade upp sig i tvåseparata klader med lite variation mellan individerna i de fylogenetiska träden. Utseendet påträden skulle kunna tyda på att L. dubia invandrat till Skandinavien flera gånger och kansketill och med från flera refuger, en i söder i Centraleuropa och en i öster i närheten avKaukasus. Trädens utseende tyder även på att arten egentligen är flera, kanske kryptiska arter.

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  • 78.
    Lindén, Ann-Sofie
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Uggla Viktorsson, Marcus
    Halmstad University, School of Business and Engineering (SET).
    Typ och grad av samband mellan skador på stammar och rötter av gran till följd av vildsvinsbök (troliga angreppspunkter för rotröta) och vildsvinspopulationens täthet2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The Swedish wild boar (Sus scrofa) population has expanded greatly in both size and distribution during the last decades. It is well known that wild boar causes problems in the agriculture and several studies have been performed on this subject. However, there is almost no information concerning the importance of wild boar for the forestry. It is plausible that rooting could cause both rot (through physical damage to the roots) and influence the spread of rot between spruce plantations. If so, wild boar rooting could thereby lead to a loss in wood quality and harvested volumes and thus cause negative economic consequences for the forestry.This pilot study is a part of a larger research project on wild boar and its management. The aim of this study was, through a field study and annual statistics, to collect data indicating the type and degree of correlation between damage to the stems and roots due to wild boar rooting (probable attack point for rot) on spruce (Picea abies). Damage was related to the depth of the rooting, soil type, the age of the stand and an index for local wild boar density.The field study was conducted as an inventory of rooting along line transects with 50 meter intervals in spruce stands (age 30-70 years, landowner the forest enterprice Sveaskog). The inventories were conducted in southern Sweden in areas around Ulricehamn, Kalmar, Ljungby, Burseryd and Växjö.A total number of 683 wild boars rooting, in 40 different stands was recorded. Rooting with damaged roots and rooting with exposed roots are those that can lead to future rotting in spruce trees, and such made up 57% of all rootings. At rooting depth of 6-10 cm, the risk of such damages was >50% whereas at depths of 11-20, the risk was >70%. Of all rootings, 46% were located in stands on old agricultural land and 54% located at sites only used for forest regeneration. There was also a positive correlation between the number of years with wild boars in an area and the amount of rooting with damaged roots. The result shows that there is a risk that wild boar rooting, over time, could cause rot in spruce.

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  • 79.
    Lundquist, Kristin
    Halmstad University, School of Business, Engineering and Science.
    Habitat use by waterbirds in wetlands during winter and spring – a study of five wetlands in Halmstad, Sweden2018Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    During December-April in 2016/2017, five wetlands in near proximity to the city of Halmstad and four stretches along the stream Trönningeån were investigated regarding their use by birds during winter and spring. At one of the wetlands it was investigated whether non-entry rules are set accordingly to the breeding period. Furthermore, the recreational values of two of the wetlands were calculated. The five wetlands were used by a total of 37 species during the months December-April and they were occupied by mainly the same bird species with a few exceptions, showing some differences in numbers of individuals and species composition depending on wetland. The wetlands seemed to be of importance for a few wintering species as there were at least 12 species and 190 individuals at the near-coastal wetland Trönninge ängar during months December-February. The inland wetland Stjärnarps norra våtmark attracted 6 species and a surprising amount of 153 individuals during the same period. Especially the near-coastal wetlands also created for bird purposes (Trönninge ängar and Larssons våtmark) served as very important spots for migrating birds and were visited by a large number of species and attracted 1531 and 1314 individuals between months March-April. The no-entry rules regarding Trönninge ängar seemed to be up-to-date in terms of when the birds show signs of breeding. The recreational value was calculated to be almost three times higher for Trönninge ängar than for Larssons våtmark. The turnover rate for the birds in two of the wetlands showed some differences and/or patterns regarding how and when different bird species use the wetlands.

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  • 80.
    Lundquist, Kristin
    Halmstad University, School of Business, Engineering and Science.
    Vildsvinsbök i skogsmark – en studie i tre områden i Mellansverige2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In April-July in 2010, three forest dominated areas in central Sweden were studied to investigate wild boar rooting habits. The results showed that rooting mainly occurred in pine-and spruce dominated habitats where tree-ages varied between 45-90 years old and with ground surface vegetation consisting of shrubs (blueberry/lingonberry), mosses and grass. In two of the three study areas the size of rooted areas was not affected by factors such as tree species composition, forest age or vegetation ground cover, but correlations between these factors were found in one of the areas. The size of rooted areas was not affected by the population density or the time with wild boar present in the area.

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  • 81.
    Lundén, Eric
    Halmstad University, School of Business, Engineering and Science.
    Mossfloran vid vattenkvarnar i sydöstra Sverige2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Bryophytes play an important role in ecosystems in running waters and are common growing on structures in and around watermills. These watermill habitats differ from other parts of the watercourse in terms of microclimate and disturbance regime, and in providing more suitable and variable substrates. Bryophytes were sampled in and around five watermills and five reference sites 300 meters up or downstream from the watermill in the province Småland, in south-eastern Sweden. Species richness was compared between the sites and differences in community structure were analysed by a Discriminant Analysis. In 90% of the cases, the species composition was found to be specific for watermills and reference sites, and the mean species number was 57% higher at watermills than at the reference sites. Rocks and boulders in a wide range of sizes, concrete and mortar structures with pH-levels higher than that of the underlying bedrock, and stronger currents were identified as some of the causes of the higher diversity at the watermills. Restauration projects in rivers, including dam removal, constitute a potential threat to the bryophyte flora of watermills since the structures they grow on may either be removed or destroyed. Changes in microclimate and disturbance regime are other potential threats to species in these habitats.

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  • 82.
    Maaroufi, Nadia
    et al.
    Department of Ecology, Swedish University of Agricultural Sciences (SLU), Uppsala, Sweden & Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, Sweden.
    Palmqvist, Kristin
    Department of Ecology and Environmental Science (EMG), Umeå University, Umeå, Sweden.
    Bach, Lisbeth H.
    Department of Ecology and Environmental Science (EMG), Umeå University, Umeå, Sweden.
    Bokhorst, Stef
    Department of Ecological Sciences, Vrije Universiteit, Amsterdam, The Netherlands.
    Liess, Antonia
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS). Department of Ecology and Environmental Science (EMG), Umeå University, Umeå, Sweden.
    Gundale, Michael J.
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, Sweden.
    Kardol, Paul
    Department of Forest Ecology and Management, Swedish University of Agricultural Sciences (SLU), Umeå, Sweden.
    Nordin, Annika
    Umeå Plant Science Center (UPSC), Department of Forest Genetics and Plant Physiology, Swedish University of Agricultural Sciences (SLU), Umeå, Sweden.
    Meunier, Cédric L.
    Department of Ecology and Environmental Science (EMG), Umeå University, Umeå, Sweden & Alfred-Wegener-Institut, Helmholtz-Zentrum für Polar- und Meeresforschung (AWI), Biologische Anstalt Helgoland, Helgoland, Germany.
    Nutrient optimization of tree growth alters structure and function of boreal soil food webs2018In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 428, p. 46-56Article in journal (Refereed)
    Abstract [en]

    Nutrient optimization has been proposed as a way to increase boreal forest production, and involves chronic additions of liquid fertilizer with amounts of micro- and macro-nutrients adjusted annually to match tree nutritional requirements. We used a short-term (maintained since 2007) and a long-term (maintained since 1987) fertilization experiment in northern Sweden, in order to understand nutrient optimization effects on soil microbiota and mesofauna, and to explore the relationships between plant litter and microbial elemental stoichiometry. Soil microbes, soil fauna, and aboveground litter were collected from the control plots, and short- and long-term nutrient optimization plots. Correlation analyses revealed no relationships between microbial biomass and litter nutrient ratios. Litter C:N, C:P and N:P ratios declined in response to both optimization treatments; while only microbial C:P ratios declined in response to long-term nutrient optimization. Further, we found that both short- and long-term optimization treatments decreased total microbial, fungal, and bacterial PLFA biomass and shifted the microbial community structure towards a lower fungi:bacterial ratio. In contrast, abundances of most fungal- and bacterial-feeding soil biota were little affected by the nutrient optimization treatments. However, abundance of hemi-edaphic Collembola declined in response to the long-term nutrient optimization treatment. The relative abundances (%) of fungal-feeding and plant-feeding nematodes, respectively, declined and increased in response to both short-term and long-term treatments; bacterial-feeding nematodes increased relative to fungal feeders. Overall, our results demonstrate that long-term nutrient optimization aiming to increase forest production decreases litter C:N, C:P and N:P ratios, microbial C:P ratios and fungal biomass, whereas higher trophic levels are less affected. © 2018 Elsevier B.V.

  • 83.
    Madjidian, Josefin A.
    et al.
    Plant Protection Biology, Swedish University of Agricultural Sciences, Alnarp, Sweden.
    Karlsson Green, Kristina
    Halmstad University, School of Business, Engineering and Science, Centre for Innovation, Entrepreneurship and Learning Research (CIEL).
    A reply to Perry & Rowe: costs in sexual conflict research2012In: Animal Behaviour, ISSN 0003-3472, E-ISSN 1095-8282, Vol. 83, no 4, p. E14-E16Article in journal (Other academic)
  • 84.
    Martensson, Robin
    Halmstad University, School of Business and Engineering (SET).
    Behavioral disturbances in three-spined stickleback (Gasterosteus aculeatus) due to ocean acidification2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Climate change has led to an increase in CO2 absorption by the oceans. An increase in CO2 and a decrease in pH have been named ocean acidification. Recent studies have shown that not only do calcifiers suffer due to an increased solubility of calcium carbonate or other physical consequences, but fish experiences behavioral alterations. The aim of the present study was to investigate if the Three-spined Stickleback (Gasterosteus aculeatus) were affected by an elevated level of CO2.Effects were measured by conducting two behavioral experiments. One was to test if the fish were lateralizatised and the other was a test of exploratory behavior. Lateralization is a kind of right- or left handedness and decides the default action path in the relation to a stimulus. Lateralization was tested with a double T-chamber where the fish were gently forced to choose either a right of left path. The escape experiment was conducted to test exploratory behavior and boldness. The fish were put in a container in a tank with the possibility to escape. Results showed that lateralization was highly affected by experiment treatments. Fish kept at higher levels of CO2 lost their lateralization both at individual and population level. No time differences were observed in the escape experiment. The fact that an otherwise tolerant fish species showed behavioral disturbances could indicate that other teleost fish could be affected also.

  • 85.
    Mattsson, Marie
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Herrmann, B.
    Agroscope Reckenholz-Tänikon Research Station ART.
    David, M.
    Institut National de la Recherche Agronomique (INRA), UMR Environnement et Grandes Cultures, Thiverval-Grignon, France.
    Loubet, B.
    Institut National de la Recherche Agronomique (INRA), UMR Environnement et Grandes Cultures, Thiverval-Grignon, France.
    Riedo, M.
    Natural Environmental Research Council, Centre for Ecology and Hydrology, Edinburgh Research Station, Penicuik EH260QB, Midlothian, Scotland.
    Theobald, M.R.
    Natural Environmental Research Council, Centre for Ecology and Hydrology, Edinburgh Research Station, Penicuik EH260QB, Midlothian, Scotland.
    Sutton, M.A.
    Natural Environmental Research Council, Centre for Ecology and Hydrology, Edinburgh Research Station, Penicuik EH260QB, Midlothian, Scotland.
    Bruhn, D.
    Plant and Soil Science Laboratory, University of Copenhagen, Faculty of Life Sciences, Thorvaldsensvej 40, 1871 Frederiksberg C, Copenhagen, Denmark.
    Neftel, A.
    Agroscope Reckenholz-Tänikon Research Station ART, Reckenholzstrasse 191, 8046 Z¨urich, Switzerland.
    Schjoerring, J.K.
    Plant and Soil Science Laboratory, University of Copenhagen, Faculty of Life Sciences, Thorvaldsensvej 40, 1871 Frederiksberg C, Copenhagen, Denmark.
    Temporal variability in bioassays of the stomatal ammonia compensation point in relation to plant and soil nitrogen parameters in intensively managed grassland2009In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 6, no 2, p. 171-179Article in journal (Refereed)
    Abstract [en]

    The exchange of ammonia between crop canopies and the atmosphere depends on a range of plant parameters and climatic conditions. However, little is known about effects of management factors. We have here investigated the stomatal ammonia compensation point in response to cutting and fertilization of a grass sward dominated by Lolium perenne. Tall grass had a very low NH3 compensation point (around 1 nmol mol−1), reflecting the fact that leaf nitrogen (N) concentration was very low. During re-growth after cutting, leaf tissue concentrations of NO3−, NH4+, soluble N and total N increased along with apoplastic NH4+ concentrations. In contrast, apoplastic pH decreased resulting in largely unaltered NH3 compensation points. Nitrogen fertilization one week after cutting caused the apoplastic NH4+ concentration of the newly emerging leaves to increase dramatically. The NH3 compensation point peaked between 15 and 25 nmol mol−1 the day after the fertiliser was applied and thereafter decreased over the following 10 days until reaching the same level as before fertilisation. Ammonium concentrations in leaf apoplast, bulk tissue and litter were positively correlated (P=0.001) throughout the experimental period. Bulk tissue NH4+ concentrations, total plant N and soil NH4+ concentrations also showed a positive correlation. A very high potential for NH3 emission was shown by the plant litter.

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  • 86.
    Mattsson, Marie
    et al.
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS).
    Herrmann, B.
    Agroscope Reckenholz-Tänikon Research Station ART, Reckenholzstrasse 191, 8046 Zürich, Switzerland.
    Jones, S.
    Agroscope Reckenholz-Tänikon Research Station ART, Reckenholzstrasse 191, 8046 Zürich, Switzerland; Natural Environmental Research Council, Centre for Ecology and Hydrology, Edinburgh Research Station, Penicuik EH26 0QB, Midlothian Scotland.
    Neftel, A.
    Agroscope Reckenholz-Tänikon Research Station ART, Reckenholzstrasse 191, 8046 Zürich, Switzerland.
    Sutton, M.A.
    Natural Environmental Research Council, Centre for Ecology and Hydrology, Edinburgh Research Station, Penicuik EH26 0QB, Midlothian Scotland.
    Schjoerring, J.K.
    Plant and Soil Science Laboratory, University of Copenhagen, Faculty of Life Sciences, Thorvaldsensvej 40, 1871 Frederiksberg C, Copenhagen, Denmark.
    Contribution of different grass species to plant-atmosphere ammonia exchange in intensively managed grassland2009In: Biogeosciences, ISSN 1726-4170, E-ISSN 1726-4189, Vol. 6, no 1, p. 59-66Article in journal (Refereed)
    Abstract [en]

    Species diversity in grasslands usually declines with increasing input of nitrogen from fertilizers or atmospheric deposition. Conversely, species diversity may also impact the build-up of soil and plant nitrogen pools. One important pool is NH3/NH4+ which also can be exchanged between plant leaves and the atmosphere. Limited information is available on how plant-atmosphere ammonia exchange is related to species diversity in grasslands. We have here investigated grass species abundance and different foliar nitrogen pools in 4-year-old intensively managed grassland. Apoplastic pH and NH4+ concentrations of the 8 most abundant species (Lolium perenne, Phleum pratense, Festuca pratensis, Lolium multiflorum, Poa pratensis, Dactylis glomerata, Holcus lanatus, Bromus mollis) were used to calculate stomatal NH3 compensation points. Apoplastic NH4+ concentrations differed considerably among the species, ranging from 13 to 117 μM, with highest values in Festuca pratensis. Also apoplastic pH values varied, from pH 6.0 in Phleum pratense to 6.9 in Dactylis glomerata. The observed differences in apoplastic NH4+ and pH resulted in a large span of predicted values for the stomatal NH3 compensation point which ranged between 0.20 and 6.57 nmol mol−1. Three species (Lolium perenne, Festuca pratensis and Dactylis glomerata) had sufficiently high NH3 compensation point and abundance to contribute to the bi-directional NH3 fluxes recorded over the whole field. The other 5 grass species had NH3 compensation points considerably below the atmospheric NH3 concentration and were thus not likely to contribute to NH3 emission but only to NH3 uptake from the atmosphere. Evaluated across species, leaf bulk-tissue NH4+ concentrations correlated well (r2=0.902) with stomatal NH3 compensation points calculated on the basis of the apoplastic bioassay. This suggests that leaf tissue NH4+ concentrations combined with data for the frequency distribution of the corresponding species can be used for predicting the NH3 exchange potential of a mixed grass sward.

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  • 87.
    Mattsson, Marie
    et al.
    Halmstad University, School of Business and Engineering (SET).
    Schjoerring, Jan K.
    Plant Nutrition Laboratory, Department of Agricultural Sciences, Roy. Vet. and Agric. University, Copenhagen, Denmark.
    Senescence-induced changes in apoplastic and bulk tissue ammonia concentrations of ryegrass leaves2003In: New Phytologist, ISSN 0028-646X, E-ISSN 1469-8137, Vol. 160, no 3, p. 489-499Article in journal (Refereed)
    Abstract [en]

    Apoplastic and bulk tissue concentrations of NH4+ and H+ were measured during senescence of intact (attached) and excised ryegrass (Lolium perenne) leaves differing in nitrogen and carbon status. The potential for NH3 emission from the senescing leaves was estimated on the basis of the ratio between [NH4+] and [H+], designated the Γ-value, in apoplastic solution and bulk tissue.

    Attached leaves with visual symptoms of senescence showed two to three times higher [NH4+] and 0.5–1 unit lower pH in both apoplastic solution and bulk tissue extracts compared with green leaves. The Γ-values were, in all cases, low in attached leaves, ranging from 20 to 300 in the apoplastic solution and 500–900 in the bulk tissue.

    In excised leaves with high nitrogen status and low C : N ratio (≈ 10), apoplastic [NH4+] increased from around 40 µm to 2 mm after senescence in darkness for 4–9 d. Bulk tissue water [NH4+] increased in the same period to > 30 mm. Apoplastic Γ-values were in all cases < 1000, while bulk tissue Γ-values increased dramatically and reached more than 60 000 in high-nitrogen leaves.

    Ammonia compensation points predicted on the basis of apoplastic [NH4+] and pH in senescing leaves with high-nitrogen status reached 6–8 nmol mol-1 air. Consequently, senescing leaves may constitute a significant source of atmospheric NH3.

  • 88.
    Milenkovski, Susann
    et al.
    Department of Chemical Ecology/Ecotoxicology, Lund University, Lund, Sweden.
    Thiere, Geraldine
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Weisner, Stefan
    Halmstad University, School of Business, Engineering and Science, Biological and Environmental Systems (BLESS), Environmental Science, Wetland Research Centre.
    Berglund, Olof
    Department of Chemical Ecology/Ecotoxicology, Lund University, Lund, Sweden.
    Lindgren, Per-Eric
    Department of Clinical and Experimental Medicine, Division of Medical Microbiology, Linköping University, Linköping, Sweden.
    Variation of eubacterial and denitrifying bacterial biofilm communities among constructed wetlandsManuscript (preprint) (Other academic)
    Abstract [en]

    Bacteria play important roles in the transformation of nutrients in wetlands, but few studies have examined parameters affecting variation in bacterial community composition between wetlands. We compared the composition of eubacterial and denitrifying bacterial biofilm communities in 32 agricultural constructed wetlands in southern Sweden, and the extent to which wetland environmental parameters could explain the observed variation. Structure and richness of the eubacterial 16S rRNA gene and three denitrifying bacterial enzyme genes (nirK, nirS and nosZ), analysed by molecular fingerprinting methods, varied among the constructed wetlands, which could be partly explained by different environmental parameters. Results from the enzyme gene analyses were also compared to determine whether the practice of using a single denitrifying bacterial gene could characterize the overall community composition of denitrifying bacteria. We found that nirK was more diverse than both nirS and the nosZ, and the band structure and richness of the three genes were not related to the sam environmental parameters. This suggests that using a single enzyme gene may not suffice to characterize the community composition of denitrifying bacteria in constructed agricultural wetlands.

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  • 89.
    Möller Voss, Peter
    Halmstad University, School of Business and Engineering (SET).
    Vertical Farming: An agricultural revolution on the rise2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Vertical farming in urban environments has sprung out of a need to find alternatives to common practice in industrial agriculture. The way in which industrial agriculture is being conducted today has a wide spread negative impact on the environment as well as being economically inefficient in a number of ways. This essay serves to investigate the concept of vertical farming, how it might potentially alleviate some of the problems brought on by current agricultural methods and whether it might serve as a viable alternative in future industrial farming. Vertical Farming is a promising concept that combines environmental considerations with sound economics. It puts the spotlight on the negative aspects of current agriculture and provides a solution in accord with future global societal structures. However, as with any novelty, improvements can be made, a lot of which comes with technological improvements of a concept in development.

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    Vertical Farming - An agricultural revolution on the rise
  • 90.
    Mühle, Lesley
    et al.
    Technische Universität Braunschweig, Germany.
    Rohe, Lena
    Technische Universität Braunschweig, Germany.
    Flenner, Ida
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS).
    Suhling, Frank
    Technische Universität Braunschweig, Germany.
    Atmungsverhalten von Orthetrum cancellatum–Larven: Einfluss der aktuellen Temperatur und der Aufzuchtsbedingungen (Odonata: Libellulidae)2009In: Libellula, ISSN 0723-6514, Vol. 28, no 1-2, p. 59-68Article in journal (Refereed)
    Abstract [en]

    Ventilation behaviour of Orthetrum cancellatum larvae: influence of the current temperature and rearing conditions (Odonata: Libellulidae) — The intensity of respiration of larval Anisoptera can be determined by observing the frequency of abdominal movements. We used this to study the influence of the current temperature on the larval respiration of O. cancellatum. We assumed that (1) the breathing rate of the larvae increases with rising temperature and that (2) the response to the current temperature depends on the rearing conditions. The larvae were kept for nine months under four different rearing conditions. The egg clutches originated from two countries in different climate zones, from southern France in the Mediterranean area and from northern Germany in the temperate zone. Our experiment revealed that the ventilation rate increased with increasing temperature. This was more pronounced with higher rearing temperatures that the larvae experienced. We interpreted this as a habituation effect. The size of the larvae influenced the ventilation rate as well. On the other hand, the genetic and geographic origin of the larvae had no significant effect.

     

  • 91.
    Nilsson, Josefin E.
    et al.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Liess, Antonia
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Ehde, Per Magnus
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Weisner, Stefan E.B.
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Mature wetland ecosystems remove nitrogen equally well regardless of initial planting2020In: Science of the Total Environment, ISSN 0048-9697, E-ISSN 1879-1026, Vol. 716, article id 137002Article in journal (Refereed)
    Abstract [en]

    Restored and constructed semi-natural wetlands are increasingly used in the agricultural landscape to intercept nutrients from surface waters. Vegetated surface-flow wetlands remove more nitrogen (N) than those without vegetation. However, changes in N removal over time as differently vegetated wetlands progress from early successional stages to mature systems are less investigated. We monitored three different types of initial planting over the course of 12 years, with the aim to examine how planting of newly constructed wetlands affects long-term N removal. All our data were collected in an experimental wetland facility in south-western Sweden. The facility consists of 18 identical small (ca. 25 m2) surface-flow wetlands, simulating semi-natural wetlands in an agricultural landscape. Initially, the 18 wetlands were randomly divided into three treatments (vegetation types) with six replicates each and planted with (1) emergent vegetation, (2) submerged vegetation and (3) no vegetation for free development. Vegetation succession afterwards progressed uninhibited in all wetlands. Emergent vegetation wetlands initially removed more N than both submerged vegetation and free development wetlands. We found that N removal in submerged vegetation and free development wetlands increased with ecosystem age, whereas N removal in emergent vegetation wetlands did not. N removal in all three vegetation types converged when the wetlands reached a more mature state, around 8 years after wetland construction. However, although all wetlands contained emergent vegetation in year 8, the proportion of emergent vegetation cover and vegetation composition still differed substantially between wetland types. Our study indicates that it is not the cover of emergent vegetation per se which promotes higher N removal in more mature wetlands, but the maturation process itself; mature wetlands despite differing emergent vegetation coverage achieved equally high N removal. In conclusion, once wetlands reach maturity, beneficial effects of initial planting on N removal disappear. © 2020 The Authors. Published by Elsevier B.V.

  • 92.
    Norddahl, Gudmundur L.
    et al.
    Immunology Section, Institution for Experimental Medical Science, Lund University, Lund, Sweden.
    Pronk, Cornelis J.
    Immunology Section, Institution for Experimental Medical Science, Lund University, Lund, Sweden.
    Wahlestedt, Martin
    Immunology Section, Institution for Experimental Medical Science, Lund University, Lund, Sweden.
    Sten, Gerd
    Immunology Section, Institution for Experimental Medical Science, Lund University, Lund, Sweden.
    Nygren, Jens M.
    Halmstad University, School of Health and Welfare, Centre of Research on Welfare, Health and Sport (CVHI).
    Ugale, Amol
    Immunology Section, Institution for Experimental Medical Science, Lund University, Lund, Sweden.
    Sigvardsson, Mikael
    Institution of Clinical and Experimental Medicine, Linköping University, Linköping, Sweden.
    Bryder, David
    Immunology Section, Institution for Experimental Medical Science, Lund University, Lund, Sweden.
    Accumulating mitochondrial DNA mutations drive premature hematopoietic aging phenotypes distinct from physiological stem cell aging2011In: Cell Stem Cell, ISSN 1934-5909, E-ISSN 1875-9777, Vol. 8, no 5, p. 499-510Article in journal (Refereed)
    Abstract [en]

    Somatic stem cells mediate tissue maintenance for the lifetime of an organism. Despite the well-established longevity that is a prerequisite for such function, accumulating data argue for compromised stem cell function with age. Identifying the mechanisms underlying age-dependent stem cell dysfunction is therefore key to understanding the aging process. Here, using a model carrying a proofreading-defective mitochondrial DNA polymerase, we demonstrate hematopoietic defects reminiscent of premature HSC aging, including anemia, lymphopenia, and myeloid lineage skewing. However, in contrast to physiological stem cell aging, rapidly accumulating mitochondrial DNA mutations had little functional effect on the hematopoietic stem cell pool, and instead caused distinct differentiation blocks and/or disappearance of downstream progenitors. These results show that intact mitochondrial function is required for appropriate multilineage stem cell differentiation, but argue against mitochondrial DNA mutations per se being a primary driver of somatic stem cell aging.

  • 93.
    Noreman, Rickard
    Halmstad University, School of Business, Engineering and Science.
    Pollinerande insekters (Apidae, Rhopalocera och Syrphidae) förekomst intill vägar i södra Sverige.2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    More conservation programs directed towards insects are needed in order to prevent the continue decline in which many insect species in the world are heading to. New ways to use the remaining microhabitats are needed to mitigate the fragmentation and degradation that urbanization and modern agriculture have contributed to in the southern Swedish landscapes. This study focusses on how microhabitats like road-verges can help the conservation projects of pollinating insects. To increase the knowledge about three groups of pollinators (Apidae, Rhopalocera and Syrphidae) and their distribution between two different microhabitats, a malaise trap was set up in road verges and in sample locations further away from the road-verges. The result from this study shows that road-verges are a microhabitat that could work as mitigation to the decline of some pollinating species, if right actions are taken. This study shows that Syrphidae was most acceptant to the hostile environment close to the roads. If these actions are going to help the most treated species is still unknown.

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  • 94.
    Olsson, Cecilia
    Halmstad University, School of Business and Engineering (SET).
    Pellet group count of roe deer ( Capreolus capreolus ) at Herrevad Abbey: How has the hunting affected the population and how will it develop?2011Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
    Abstract [en]

    The land around Herrevad Abbey consists mostly of pastures with a lot of old coarse oaks, a touch of broad-leaved decidous forest andmixed deciduous and coniferous forest.

    In the year 2010 the Swedish Environmental Protection Agency became owner of the area around Herrevad Abbey, previously owned by the Swedish National Fortification Administration. A high pressure from hunting occurred during the Swedish National Fortification Administration ownership. This resulted in a decrease of the roe deer (Capreolus capreolus L.) population.

    A pellet-group count is a reliable, indirect inventory method that is used with high frequence within wildlife management since the 1930s. Pellet-group count is used in Swedish Wildlife research since the 1977 at Grimsö Research Station and today an increasing interest for this method is seen both in nature management, among hunters and  in the Swedish Association for Hunters.

    Through a pellet-group count of a roe deer population, an underestimated index of the total density is shown, which means that the investigated population can be larger than the survey shows. The pellet-group count in this study covered 3,20 km-2 with a total of 315 plots. The plot had a circular shape and covered 10m2, which is recommended for roe deer surveys. Each plot was investigated twice, one round clockwise and one round counter clock-wise to increase the precision of the survey. The calculation showed 10,76 roe deer per 1,00 km-2 in winter population during 2010; with a 10% set-off for winter mortality and 8,22 roe deer per 1,00 km-2 in winter population with a 30% set-off. The density with 10,76 roe deer /km-2 is low compared to experimental plots at Bogesund, Ekenäs, where the population is estimated to around 17-23 roe deer/ 1,00 km-2. A calculation for carrying capacity shows that the population will reach the density limit within four years at Herrevad Abbey.

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  • 95.
    Parsapoor, Mahboobeh
    et al.
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    Brooke, John Martin
    School of Computer Science, Faculty of Engineering and Physical Science, University of Manchester, Manchester, United Kingdom.
    Svensson, Bertil
    Halmstad University, School of Information Technology, Halmstad Embedded and Intelligent Systems Research (EIS), Centre for Research on Embedded Systems (CERES).
    A new computational intelligence model for long-term prediction of solar and geomagnetic activity2015In: Proceedings of the Twenty-Ninth AAAI Conference on Artificial Intelligence, 2015, Vol. 6, p. 4192-4193Conference paper (Refereed)
    Abstract [en]

    This paper briefly describes how the neural structure of fear conditioning has inspired to develop a computational intelligence model that is referred to as the brain emotional learning-inspired model (BELIM). The model is applied to predict long step ahead of solar activity and geomagnetic storms. © Copyright 2015, Association for the Advancement of Artificial Intelligence (www.aaai.org). All rights reserved.

  • 96.
    Persson, Jesper
    et al.
    Sveriges Lantbruksuniversitet.
    Weisner, Stefan
    Halmstad University, School of Business and Engineering (SET), Biological and Environmental Systems (BLESS), Wetland Research Centre.
    Integrera teknik och biologi vid utformning och anläggning2002In: Våtmarksboken: Skapande och nyttjande av värdefulla våtmarker / [ed] Karin Tonderski, Stefan Weisner, Jan Landin, Hans Oscarsson, Göteborg: Vattenstrategiska forskningsprogrammet (VASTRA) , 2002, p. 252-270Chapter in book (Refereed)
  • 97.
    Persson, Linnéa
    Halmstad University, School of Business, Engineering and Science.
    Skyddsvärda kärlväxter i Haväng och Vitemölla strandbackar: – utbredning, hot och skötsel2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Semi-natural grasslands are one of the most threatened habitats in Scandinavia. The grassland in this study is situated in the northern part of the nature preserve of Haväng och Vitemölla strandbackar in the province of Skåne and consists of grey dunes and a pasture which partly consists of calcareous grassland and the vegetation type sand steppe which is very rare in Sweden. There are several threatened plants in the area and during the summer of 2017 their distribution was registered to be able to protect them during conservation management. The results showed that most of the area contained important species and the most important areas to protect were the sand steppe areas. This is probably due to the dry, sandy, calcareous and nutrient poor conditions in these areas which many of the threatened plants are connected to. Most of the threatened plants were found in abundance in the area but have a limited distribution in Sweden. The population of Eryngium maritimum however was very small and is threatened by extinction. The plants in the area are threatened by a long-term process of nutrient enrichment and continuous leakage of calcium which may lead to lower pH and a more nutrient rich soil which leads to a higher availability of phosphorous. This may lead to a change in species composition and loss of species richness. Continuous grazing, soil disturbance to expose lime-rich sand and also removal of litter to minimize the nutrient levels are needed to maintain favorable conditions in the area. However, the number of important species requires attention and careful planning, especially in the sand steppe areas. 

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  • 98.
    Peters, Wibke
    et al.
    Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, MT, United States & Bavarian State Institute of Forestry (LWF), Freising, Germany.
    Hebblewhite, Mark
    Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, MT, United States.
    Mysterud, Atle
    Centre for Ecological and Evolutionary Synthesis, Department Biosciences, University of Oslo, Oslo, Norway.
    Eacker, Daniel
    Wildlife Biology Program, Department of Ecosystem and Conservation Sciences, University of Montana, Missoula, MT, United States.
    Hewison, A. J. Mark
    CEFS, University de Toulouse, INRA, Castanet Tolosan, France.
    Linnell, John D. C.
    Norwegian Institute for Nature Research (NINA), Trondheim, Norway.
    Focardi, Stefano
    stituto dei Sistemi Complessi, CNR, Sesto Fiorentino, Italy.
    Urbano, Ferdinando
    Eurodeer Project, freelance consultan.
    De Groeve, Johannes
    Department of Geography, Ghent University, Gent, Belgium.
    Gehr, Benedikt
    Department of Evolutionary Biology and Environmental Studies, University of Zurich, Zurich, Switzerland.
    Heurich, Marco
    Department of Conservation and Research, Bavarian Forest National Park, Grafenau, Germany.
    Jarnemo, Anders
    Halmstad University, School of Business, Engineering and Science, The Rydberg Laboratory for Applied Sciences (RLAS).
    Kjellander, Petter
    Grimsö Wildlife Research Station, Department of Ecology, Swedish University of Agricultural Science (SLU), Riddarhyttan, Sweden.
    Kröschel, Max
    Chair of Wildlife Ecology and Management, University of Freiburg, Freiburg, Germany & Forest Research Institute of Baden-Wuerttemberg, Freiburg im Breisgau, Germany.
    Morellet, Nicolas
    CEFS, University de Toulouse, INRA, Castanet Tolosan, France.
    Pedrotti, Luca
    Parco Nationale dello Stelvio, Glorenza (BZ), Italy.
    Reinecke, Horst
    Department of Wildlife Sciences & Institute for Wildlife biology of Göttingen and Dresden, University of Göttingen, Göttingen, Germany.
    Sandfort, Robin
    Institute of Wildlife Biology and Game Management, University of Natural Resources and Life Sciences, Vienna, Austria.
    Sönnichsen, Leif
    Mammal Research Institute, Polish Academy of Sciences, Białowieża, Poland & Leibniz Institute for Zoo and Wildlife Research (IZW), Berlin, Germany.
    Sunde, Peter
    Deptartment of Bioscience – Wildlife Ecology, Aarhus University, Aarhus, Denmark.
    Cagnacci, Francesca
    Biodiversity and Molecular Ecology Department, Research and Innovation Centre, Fondazione Edmund Mach, San Michele all'Adige (TN), Italy & Organismic and Evolutionary Department, Harvard University, Cambridge, MA, United States.
    Large herbivore migration plasticity along environmental gradients in Europe: life-history traits modulate forage effects2018In: Oikos, ISSN 0030-1299, E-ISSN 1600-0706, Vol. 128, no 3, p. 416-429Article in journal (Refereed)
    Abstract [en]

    The most common framework under which ungulate migration is studied predicts that it is driven by spatio–temporal variation in plant phenology, yet other hypotheses may explain differences within and between species. To disentangle more complex patterns than those based on single species/ single populations, we quantified migration variability using two sympatric ungulate species differing in their foraging strategy, mating system and physiological constraints due to body size. We related observed variation to a set of hypotheses. We used GPS-collar data from 537 individuals in 10 roe Capreolus capreolus and 12 red deer Cervus elaphus populations spanning environmental gradients across Europe to assess variation in migration propensity, distance and timing. Using time-to-event models, we explored how the probability of migration varied in relation to sex, landscape (e.g. topography, forest cover) and temporally-varying environmental factors (e.g. plant green-up, snow cover). Migration propensity varied across study areas. Red deer were, on average, three times more migratory than roe deer (56% versus 18%). This relationship was mainly driven by red deer males which were twice as migratory as females (82% versus 38%). The probability of roe deer migration was similar between sexes. Roe deer (both sexes) migrated earliest in spring. While territorial male roe deer migrated last in autumn, male and female red deer migrated around the same time in autumn, likely due to their polygynous mating system. Plant productivity determined the onset of spring migration in both species, but if plant productivity on winter ranges was sufficiently high, roe deer were less likely to leave. In autumn, migration coincided with reduced plant productivity for both species. This relationship was stronger for red deer. Our results confirm that ungulate migration is influenced by plant phenology, but in a novel way, that these effects appear to be modulated by species-specific traits, especially mating strategies. © 2018 The Authors. Oikos © 2018 Nordic Society Oikos

  • 99.
    Petersson, Germund
    Halmstad University, School of Business, Engineering and Science.
    Skogsmyror (Formica rufa-gruppen) i monokulturell granskog och i nyckelbiotoper med hög andel gran i södra Sverige2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Ants belonging to the Formica rufa group (wood ants) and their mounds have a large impact on forest ecosystems. This makes them considered keystone species. Several species of wood ants are threatened globally according to the IUCN red list. In this degree project mound densities and mound volumes were evaluated and compared between Norway spruce monocultures and high part Norway spruce woodland key habitats (WKHs) in southern Sweden. There were no significant differences in neihter mound densities nor mound volumes between the two stand types. However, mounds were distributed differently within the stand types and tree density correlated negatively to mound density in both stand types. Wood ant mounds were absent in the interior of monoculture stands, except in light gaps, while several mounds where located in the interior of WKHs. My results suggest that there is not enough light in the interior of monocultures in southern Sweden for wood ants to be able to colonize. Large monoculture areas may lack wood ants if gaps are missing. Therefore, gaps inside monocultures should be made more common in Swedish forests in order to benefit wood ants in production forests. Small clearcuts seem to benefit wood ant dispersal in monocultural stands. Therefore, smaller clearcuts should be preferred over the large areas presently clearcutted due to the negative effects of large clearcuts on wood ants.

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  • 100.
    Petersson, Linn
    Halmstad University, School of Business, Engineering and Science.
    Hur markegenskaper i produktionsskog påverkas av bök från vildsvin (Sus scrofa) i sydvästra Sverige2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A balance between large-scale and small-scale disturbance is important for maintaining species diversity on landscape level. Wild boar rooting contributes to small-scale disturbance when leaving patches bare of soil. Knowledge is scarce regarding their impact on soil properties in managed spruce forests in south-west Sweden. Therefore, the objective of this study was to determine the effects of wild boar rooting on soil physical and chemical properties, by taking soil samples from the centre, the edge and outside of disturbed patches. Rooting activities significantly increased soil moisture, organic matter, total N and pH but did not affect total P in this study. Areas with high number of disturbed patches had higher soil moisture and organic matter compared to areas with intermediate and few disturbed patches. These new soil characteristics can favour species diversity and ultimately increase productivity in managed forests. The results of this study indicate that wild boar activity contributes to more positive than negative effects in managed spruce forests and focus should therefore lie on preventing wild boar rooting in other areas more sensitive to this disturbance. It is also important to disseminate information and knowledge about the wild boar's positive and negative impact on managed forests in order to better prevent the negative effects and strengthen the positive ones.

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