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  • 1.
    Abdelfattah, Ahmed
    et al.
    Univ Mediterranea Reggio Calabria, Italy.
    Malacrinò, Antonino
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Wisniewski, Michael
    USDA ARS, WV 25430 USA.
    Cacciola, Santa O.
    Univ Catania, Italy.
    Schena, Leonardo
    Univ Mediterranea Reggio Calabria, Italy.
    Metabarcoding: A powerful tool to investigate microbial communities and shape future plant protection strategies2018In: Biological control (Print), ISSN 1049-9644, E-ISSN 1090-2112, Vol. 120Article in journal (Refereed)
    Abstract [en]

    Microorganisms are the main drivers shaping the functioning and equilibrium of all ecosystems, contributing to nutrient cycling, primary production, litter decomposition, and multi-trophic interactions. Knowledge about the microbial assemblies in specific ecological niches is integral to understanding the assemblages interact and function the function, and becomes essential when the microbiota intersects with human activities, such as protecting crops against pests and diseases. Metabarcoding has proven to be a valuable tool and has been widely used for characterizing the microbial diversity of different environments and has been utilized in many research endeavors. Here we summarize the current status of metabarcoding technologies, the advantages and challenges in utilizing this technique, and how this pioneer approach is being applied to studying plant diseases and pests, with a focus on plant protection and biological control. Current and future developments in this technology will foster a more comprehensive understanding of microbial ecology, and the development of new, innovative pest control strategies.

  • 2.
    Adams, David A.
    et al.
    Department of Biology, Middle Tennessee State University, USA.
    Walck, Jeffery L.
    Department of Biology, Middle Tennessee State University, USA.
    Howard, R. Stephen
    Department of Biology, Middle Tennessee State University, USA.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Ecology. Linköping University, The Institute of Technology.
    Forest Composition and Structure onGlade-forming Limestones in Middle Tennessee2012In: Castanea, ISSN 0008-7475, Vol. 77, no 4, p. 335-347Article in journal (Refereed)
    Abstract [en]

    Within a successional context, the vegetation associated with the cedar gladeecosystem in middle Tennessee develops from bare limestone bedrock to subclimax redcedar,preclimax oak-hickory, and climax mixed hardwood forests. Studies on the composition andstructure of forests associated with cedar glade–forming limestones (Lebanon, Ridley) are rare.We sampled the canopy and understory of six forest stands in middle Tennessee on theselimestones. Observed number of canopy species was 14–24 across stands; estimated richnesswas greater by 1–3 species (bootstrap) or 3–6 species (first-order jackknife) than observedrichness. With the exception of Ailanthus altissima in one stand, all other canopy species werenative. Juniperus virginiana, Fraxinus americana, Carya ovata, and Quercus muehlenbergii wereprimary canopy components in 4 or 6 stands, and C. glabra, Q. shumardii, Ulmus alata, F.quadrangulata, Q. alba, and Q. velutina in 2–3 stands. When we included stands from apreviously published study (most on the non-glade Carters Limestone) with our data, aprincipal components analysis identified three groups with the axes approximating a moisturebedrockgradient and a time-successional gradient. An examination of regeneration in ourstands predicts that (1) mesophytes and/or fire-sensitive species (Acer saccharum, Fraxinus spp.,Celtis spp.) will increase and (2) xerophytes and/or fire-adapted species (Quercus spp., Caryaspp.) will decrease. Altogether, our results strongly suggest that the oak-hickory stage shown insuccessional outlines of vegetation development associated with the cedar glade ecosystem maynot occur in its current state in the future.

  • 3.
    Akoto, Brenda
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Is spring burning a viable management tool for species-rich grasslands?2012Independent thesis Advanced level (degree of Master (Two Years)), 80 credits / 120 HE creditsStudent thesis
    Abstract [en]

    Semi- natural grasslands are species-rich and also one of the most threatened biotopes in Europe. The area of these grasslands has declined and grassland vegetation is threatened as a result of lack of management and land use change. Appropriate management is therefore required to maintain the conservation values and high species richness of semi- natural grasslands. Traditional management, that is, grazing or annual mowing is expensive, which motivates evaluation of alternative cheaper methods of management. Burning is less costly and therefore I evaluated burning along with the conventional methods. The study addressed the main question: is burning an option to mowing and grazing? I searched the literature for available studies suitable for metaanalysis, but located only detailed reports from a series of eleven Swedish long-term field trials. In addition, I collected data in the only one of these trials still running. To facilitate metaanalysis, l used different indicator systems of classification of grassland plants then calculating the odds for a random record being an indicator after one, eight, fourteen, twenty-eight and thirty-nine spring burns. The results show an increasing proportion of grassland indicators of good management in the mowed and grazed plots compared with the burnt plots, indicating a general negative effect of burning on grassland plants compared with mowing and grazing. Hence, burning is not an appropriate long-term management method if the aim is to maintain vegetation diversity in semi-natural grassland.

  • 4.
    Albouy, Camille
    et al.
    IFREMER, France.
    Archambault, Philippe
    Univ Laval, Canada.
    Appeltans, Ward
    UNESCO, Belgium.
    Araujo, Miguel B.
    CSIC, Spain; Univ Evora, Portugal; Univ Copenhagen, Denmark.
    Beauchesne, David
    Univ Quebec Rimouski, Canada.
    Cazelles, Kevin
    Univ Guelph, Canada.
    Cirtwill, Alyssa
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering. Univ Canterbury, New Zealand.
    Fortin, Marie-Josee
    Univ Toronto, Canada.
    Galiana, Nuria
    CNRS, France.
    Leroux, Shawn J.
    Mem Univ, Canada.
    Pellissier, Loik
    Swiss Fed Inst Technol, Switzerland; Swiss Fed Res Inst WSL, Switzerland.
    Poisot, Timothee
    Univ Montreal, Canada; McGill Univ, Canada.
    Stouffer, Daniel B.
    Univ Canterbury, New Zealand.
    Wood, Spencer A.
    Univ Washington, WA 98195 USA.
    Gravel, Dominique
    Univ Montreal, Canada; Univ Sherbrooke, Canada.
    The marine fish food web is globally connected2019In: Nature Ecology & Evolution, E-ISSN 2397-334X, Vol. 3, no 8, p. 1153-+Article in journal (Refereed)
    Abstract [en]

    The productivity of marine ecosystems and the services they provide to humans are largely dependent on complex interactions between prey and predators. These are embedded in a diverse network of trophic interactions, resulting in a cascade of events following perturbations such as species extinction. The sheer scale of oceans, however, precludes the characterization of marine feeding networks through de novo sampling. This effort ought instead to rely on a combination of extensive data and inference. Here we investigate how the distribution of trophic interactions at the global scale shapes the marine fish food web structure. We hypothesize that the heterogeneous distribution of species ranges in biogeographic regions should concentrate interactions in the warmest areas and within species groups. We find that the inferred global metaweb of marine fish-that is, all possible potential feeding links between co-occurring species-is highly connected geographically with a low degree of spatial modularity. Metrics of network structure correlate with sea surface temperature and tend to peak towards the tropics. In contrast to open-water communities, coastal food webs have greater interaction redundancy, which may confer robustness to species extinction. Our results suggest that marine ecosystems are connected yet display some resistance to perturbations because of high robustness at most locations.

  • 5.
    Alriksson, Emelie
    Linköping University, Department of Behavioural Sciences and Learning. Linköping University, Department of Physics, Chemistry and Biology.
    Höns återhämtning efter stress samt domesticeringens effekter: En biologisk studie med ett lärarperspektiv2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The biological study has shown that behaviour of laying hens has changed through domestication and the hens have adapted to live with humans. They have developed less fear of humans and more resistance to stress. In this study hens’ recovery after a stressful experience has been studied. A comparison between the breeds White Leghorn and red junglefowl has been made to see how the domestication has affected the recovery. The questions of this study are therefore: How long does it take for hens’ to recover their natural behaviour, not stressrelated, after a stressful experience? Are there any differences in recovery between the different breeds White Leghorn and red junglefowl? The results did not show a specific time for recovery, but a distinct recovery was noticed in Relaxed Behaviour, Comfort Behaviour, Perch, Vocalisation and Stand Alert. This beacause of the behaviours differed significantly with time. Also significant differences existed between the breeds, both in behaviours that showed recovery and in behavious that did not. A conclusion of what breed that recovered fastest was difficult to make. This because of the differences of behaviour showed different tendencies in recovery. The differences in recovery between the sexes showed tendencies that the males recovered fastest. The domestication has also been studied from a teacherperspective. The study showed that domestication can be a part of biologyeducation in the fields of evolution and genetics in the grades 7-9.

  • 6.
    Alriksson, Felicia
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Individuell tillväxt och substratval hos en lokalt differentierad population av Asellus aquaticus2013Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Local differentiation may occur during a short period of time and is part of the formation of new species. The isopod Asellus aquaticus is an example of a species in which local adaptation has occurred during a short period of time. An establishment of stonewort (Chara spp.) vegetation in Lake Tåkern (in the 2000) resulted in two different Asellus ecotypes; a lighter pigmented, smaller one that lives among stoneworts grazing periphytic algae, and a darker, larger ecotype that feeds on decaying leaves in reed (Phragmites australis vegetation. The purpose of this study was to examine whether there are differences in growth between ecotypes, depending on whether the food was periphytic algae or leaves, and to study the choice of substrates between the two food types. For the study, animals from both habitats were brought in from Lake Tåkern to the laboratory. I found that both the reed and the stonewort animals grew better when feeding on periphytic algae than on leaves, but that there was no difference in weight gain between the two ecotypes. There was no indication that the animals preferred any of the substrates. Results suggest that despite earlier noted differences in behavior, size and pigmentation (which differentiation had brought), there is no evidence that Asellus aquaticus has adapted to feed on plant matter prevailing in their original habitat. The animals grew better when the food was algae maybe due to that the algae, as previous studies show, are easier assimilated, whereas Asellus has to eat a larger amount of leaves to reach the same energy intake.

  • 7.
    Anderson, Malin
    Linköping University, Department of Physics, Chemistry and Biology, Ecology .
    Dynamics of phosphorus transport and retention in a wetland receiving drainage water from agricultural clay soils2011Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    A constructed wetland (0.08 ha) receiving drainage water from a small agricultural catchment (22 ha) with clay soil, was investigated with respect to phosphorus dynamics and retention. The aim was to evaluate the function of the wetland with respect to phosphorus retention, and relate that to gross sedimentation as measured with sediment traps. Hydraulic load and phosphorus retention were estimated for 2003-2010 based on monitoring data. Furthermore, water quality dynamics was studied during three intensive sampling periods of 3-5 days during 2010. For each period, phosphorus retention was calculated and the relationship between flow and phosphorus concentrations analysed. Additionally, the gross sedimentation rate was estimated using sediment traps, and the phosphorus, carbon and nitrogen content analysed. The results suggested that there was no net retention of phosphorus during 2003-2010, except for 04/05. During the intensive sampling periods, release of phosphorus from the wetland mainly occurred during high flow. Sediment analyses showed that settling of inflow particles mostly occurred in the inlet pond, while the sediment found in a shallow vegetated area and outlet pond likely originated from internal processes rather than from the catchment. In fact, the gross sedimentation of phosphorus during April-July and July-August, respectively, exceeded the measured phosphorus inflow. The results showed that short periods with rapid flow increases were crucial for the wetlands function and thus high frequency sampling must be done during these periods. Furthermore, it seems that the particles lost from the catchment during high flows are too small to settle in the wetland.

  • 8.
    Andersson, Marie
    Linköping University, Department of Physics, Chemistry and Biology, Ecology .
    Oak (Quercus robur L.) mortality in south-eastern Sweden: influence of weather and environmental variables2009Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    The complex interplay between biotic and abiotic factors, believed to be responsible for several oak declines in European oak stands during the last three decades, remains poorly understood. Hence, this study aims at clarifying the temporal process of oak declines, as well as identifying individual tree and environmental variables that increase the risk of oak mortality. The study was performed in one of the few areas in northern Europe still holding high densities of old oaks (Quercus robur L.). Cross dating revealed that most trees had died during the last decade. Averaged chronologies and multiple chronological clustering suggested that the onset of the oak decline happened in 1992, when a severe drought took place. Two of the sites showed a rather short time period of heavily reduced growth prior to death, most likely caused by an insect defoliation in combination with a mildew infection of the replacement shoots. Environmental variables presented a rather weak influence on oak mortality. The results support the idea of attributing oak mortality to a combination of long- and short-term stresses, and emphasize the importance of including present as well as past factors when analysing the causes of oak declines.

  • 9.
    Andersson, Natasja
    Linköping University, Department of Physics, Chemistry and Biology.
    Personlighetsvariationer hos mjölkkor2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this study was to investigate if different personality dimensions existed in dairy cows of two breeds (SRB and Holstein) and if these personality dimensions differed between breed, age and how the animals were placed in the loose housing system. To investigate behavioural consistency, the cows were observed in three different situations: uninterrupted in their home pen, during milking and with a novel object in their home pen. Normal and social behaviour was observed as well as stepping and kicking during milking and interactions with the novel object. Twelve behavioural variables were used in a principal component analysis, which showed two components that together explained 51,2 % of the total variance. The first component reflected aggression and extraversion, which are included in agreeableness and extraversion in the human five-factor model. The second component reflected fear and introversion, which are included in neuroticism and extraversion in the same model. Independent-samples T test showed no significant differences between any of the components and breed or placement in the loose housing system p>0,05, however there was a tendency between the first component and age, where the older group showed a more defined personality p<0,1. Other studies have showed that personality dimensions such as agreeableness, neuroticism and extraversion often exist in several species. Different personalities cope with stressful situations in different ways, making this topic relevant to the improvement of animal welfare.

  • 10.
    Anderzén, Emma
    Linköping University, Department of Physics, Chemistry and Biology.
    Beror förekomsten av sjöfågel i anlagda våtmarker på våtmarkens ålder och area?2011Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    From the perspective of preservation it is important to understand how waterfowl are influenced by wetlands created by humans. Since 2004 the municipality of Linköping has created several wetlands which, among others, have attracted the threatened species the Horned Grebe, Podiceps auritus. The Horned Grebe is listed on the Swedish Red List of Threatened Species. Wetlands are important for bird life for many reasons. Among other things, the birds use them to seek shelter from predators, breed there or rest on their way to the breeding sites. Previous studies have shown that there are more birds in larger wetlands, and that age of the wetland does matter for which birds can be found there. By counting the number of individuals of birds and also the different species in the wetlands we found that both age and size of the wetland are important for which birds that are attracted. It also appears that the birds thrive when there are several wetlands in the area, and of different size and age. We also found that the Horned Grebe preferred smaller wetlands and that their abundance increased with increasing numbers of Black-Headed Gulls.

  • 11.
    Averhed, Björn
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University.
    Kan förändringar i bottenfaunan påvisas två år efter en bäckrestaurering?2010Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of this work is to analyze if a change in the benthic community can be detected two years after a restoration of a small stream. The samples were taken in a small stream at Tinnerö Eklandskap just south of Linköping. In addition to the restored area, two reference sites upstream and downstream of the restored area were sampled to compare to the restored site. The method used for sampling of benthic fauna in the stream was kick sampling. ASPT, Berger-Parker and Renkonen-indices were used to find out if there was any difference between the reference areas and the restored area. In addition to indices, rank-abundance curves and species lists were made to see if there was any trend difference between the different areas. The only index that showed a difference between the different areas was Berger-Parker diversity index. The reason why there were no greater differences between the areas may be due to the fact that two years is too short to allow time for the benthos to re-colonize the restored area.

  • 12.
    Baiser, Benjamin
    et al.
    Univ Florida, FL 32611 USA.
    Gravel, Dominique
    Univ Sherbrooke, Canada.
    Cirtwill, Alyssa
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering.
    Dunne, Jennifer A.
    Santa Fe Inst, NM 87501 USA.
    Fahimipour, Ashkaan K.
    Univ Oregon, OR 97403 USA.
    Gilarranz, Luis J.
    Eawag Swiss Fed Inst Aquat Sci and Technol, Switzerland.
    Grochow, Joshua A.
    Univ Colorado, CO 80309 USA.
    Li, Daijiang
    Univ Florida, FL 32611 USA.
    Martinez, Neo D.
    Univ Arizona, AZ USA.
    McGrew, Alicia
    Univ Florida, FL USA.
    Poisot, Timothee
    Univ Montreal, Canada.
    Romanuk, Tamara N.
    Dalhousie Univ, Canada.
    Stouffer, Daniel B.
    Univ Canterbury, New Zealand.
    Trotta, Lauren B.
    Univ Florida, FL 32611 USA.
    Valdovinos, Fernanda S.
    Univ Michigan, MI 48109 USA.
    Williams, Richard J.
    Vibrant Data Inc, CA USA.
    Wood, Spencer A.
    Univ Washington, WA 98195 USA.
    Yeakel, Justin D.
    Santa Fe Inst, NM 87501 USA; Univ Calif Merced, CA USA.
    Ecogeographical rules and the macroecology of food webs2019In: Global Ecology and Biogeography, ISSN 1466-822X, E-ISSN 1466-8238, Vol. 28, no 9, p. 1204-1218Article in journal (Refereed)
    Abstract [en]

    Aim

    How do factors such as space, time, climate and other ecological drivers influence food web structure and dynamics? Collections of well‐studied food webs and replicate food webs from the same system that span biogeographical and ecological gradients now enable detailed, quantitative investigation of such questions and help integrate food web ecology and macroecology. Here, we integrate macroecology and food web ecology by focusing on how ecogeographical rules [the latitudinal diversity gradient (LDG), Bergmann's rule, the island rule and Rapoport's rule] are associated with the architecture of food webs.

    Location

    Global.

    Time period

    Current.

    Major taxa studied

    All taxa.

    Methods

    We discuss the implications of each ecogeographical rule for food webs, present predictions for how food web structure will vary with each rule, assess empirical support where available, and discuss how food webs may influence ecogeographical rules. Finally, we recommend systems and approaches for further advancing this research agenda.

    Results

    We derived testable predictions for some ecogeographical rules (e.g. LDG, Rapoport's rule), while for others (e.g., Bergmann's and island rules) it is less clear how we would expect food webs to change over macroecological scales. Based on the LDG, we found weak support for both positive and negative relationships between food chain length and latitude and for increased generality and linkage density at higher latitudes. Based on Rapoport's rule, we found support for the prediction that species turnover in food webs is inversely related to latitude.

    Main conclusions

    The macroecology of food webs goes beyond traditional approaches to biodiversity at macroecological scales by focusing on trophic interactions among species. The collection of food web data for different types of ecosystems across biogeographical gradients is key to advance this research agenda. Further, considering food web interactions as a selection pressure that drives or disrupts ecogeographical rules has the potential to address both mechanisms of and deviations from these macroecological relationships. For these reasons, further integration of macroecology and food webs will help ecologists better understand the assembly, maintenance and change of ecosystems across space and time.

  • 13.
    Barabas, György
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering.
    D'Andrea, Rafael
    Univ Illinois, IL 61801 USA.
    Stump, Simon Maccracken
    Yale Sch Forestry and Environm Studies, CT 06511 USA.
    Chesson's coexistence theory2018In: Ecological Monographs, ISSN 0012-9615, E-ISSN 1557-7015, Vol. 88, no 3, p. 277-303Article, review/survey (Refereed)
    Abstract [en]

    We give a comprehensive review of Chesson's coexistence theory, summarizing, for the first time, all its fundamental details in one single document. Our goal is for both theoretical and empirical ecologists to be able to use the theory to interpret their findings, and to get a precise sense of the limits of its applicability. To this end, we introduce an explicit handling of limiting factors, and a new way of defining the scaling factors that partition invasion growth rates into the different mechanisms contributing to coexistence. We explain terminology such as relative nonlinearity, storage effect, and growth-density covariance, both in a formal setting and through their biological interpretation. We review the theory's applications and contributions to our current understanding of species coexistence. While the theory is very general, it is not well suited to all problems, so we carefully point out its limitations. Finally, we critique the paradigm of decomposing invasion growth rates into stabilizing and equalizing components: we argue that these concepts are useful when used judiciously, but have often been employed in an overly simplified way to justify false claims.

  • 14.
    Barabas, György
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering. University of Chicago, IL 60637 USA.
    Michalska-Smith, Matthew J.
    University of Chicago, IL 60637 USA.
    Allesina, Stefano
    University of Chicago, IL 60637 USA; Northwestern University, IL 60208 USA.
    Self-regulation and the stability of large ecological networks2017In: NATURE ECOLOGY and EVOLUTION, ISSN 2397-334X, Vol. 1, no 12, p. 1870-+Article in journal (Refereed)
    Abstract [en]

    The stability of complex ecological networks depends both on the interactions between species and the direct effects of the species on themselves. These self-effects are known as self-regulation when an increase in a species abundance decreases its per-capita growth rate. Sources of self-regulation include intraspecific interference, cannibalism, time-scale separation between consumers and their resources, spatial heterogeneity and nonlinear functional responses coupling predators with their prey. The influence of self-regulation on network stability is understudied and in addition, the empirical estimation of self-effects poses a formidable challenge. Here, we show that empirical food web structures cannot be stabilized unless the majority of species exhibit substantially strong self-regulation. We also derive an analytical formula predicting the effect of self-regulation on network stability with high accuracy and show that even for random networks, as well as networks with a cascade structure, stability requires negative self-effects for a large proportion of species. These results suggest that the aforementioned potential mechanisms of self-regulation are probably more important in contributing to the stability of observed ecological networks than was previously thought.

  • 15.
    Barrefelt, Linnea
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Populationsutveckling och bärkraft för lodjur (Lynx lynx) i Östergötland2019Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Global biological diversity is declining at rates comparable to historic mass extinction events. Despite this, some species are returning to their former ranges, an example being the great carnivores in Europe. After being driven to the verge of extinction, most of today’s populations have recovered to a stable level. The Eurasian lynx (Lynx lynx) has re-expanded its range in Scandinavia and, after almost 100 years, is once again reproducing in southern Sweden. There are currently about 50-55 individuals in Östergötland county, and many factors implies that their number will continue to grow. By collecting and analysing data from different governmental reports and other sources I have tried to cover the development of Östergötland’s lynx population and to calculate the carrying capacity. The calculations are based on ungulate densities and amount of suitable habitat. The results of the study show that Östergötland contains a large amount of connected woodland habitat and high densities of prey, comparable to regions in Europe with high occurrence of lynx. Given these circumstances Östergötland has the capacity to support approximately 80-140 independent individuals. These numbers are twice as large as today’s population level and if reached could lead to positive as well as negative consequences for society. The lynx is a known threat to livestock but reports from recent years suggests that lynx attacks on sheep in Östergötland are limited. The effects of the current lynx population on ungulate demographics are also negligible. Although, these effects might increase with a larger lynx population, leading to lower rates of vehicle collisions and less damage in the forestry sector.

  • 16.
    Bastviken, David
    et al.
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Svensson, Teresia
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Karlsson, Susanne
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Sandén, Per
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Öberg, Gunilla
    IRES, UBC, Canada.
    Temperature sensitivity indicates enzyme controlled chlorination of soil organic matter2009In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 43, no 10, p. 3569-3573Article in journal (Refereed)
    Abstract [en]

    Old assumptions that chloride is inert and that most chlorinated organic matter in soils is anthropogenic have been challenged by findings of naturally formed organochlorines. Such natural chlorination has been recognized for several decades, but there are still very few measurements of chlorination rates or estimates of the quantitative importance of terrestrial chlorine transformations. While much is known about the formation of specific compounds, bulk chlorination remains poorly understood in terms of mechanisms and effects of environmental factors. We quantified bulk chlorination rates in coniferous forest soil using 36Cl-chloride in tracer experiments at different temperatures and with and without molecular oxygen (O2). Chlorination was enhanced by the presence of O2 and had a temperature optimum at 20 °C. Minimum rates were found at high temperatures (50 °C) or under anoxic conditions. The results indicate (1) that most of the chlorination between 4 and 40 °C was biotic and driven by O2 dependent enzymes, and (2) that there is also slower background chlorination occurring under anoxic conditions at 20 °C and under oxic conditions at 50 °C. Hence, while oxic and biotic chlorination clearly dominated, chlorination by other processes including possible abiotic reactions was also detected.

  • 17.
    Bennett, Alison E.
    et al.
    Department of Evolution, Ecology, and Organismal Biology, Ohio State University, Columbus, USA.
    Orrell, Peter
    Ecological Sciences, James Hutton Institute, Dundee, UK.
    Malacrinò, Antonino
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Pozo, Maria José
    Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín (CSIC), Granada, Spain.
    Fungal-Mediated Above–Belowground Interactions: The Community Approach, Stability, Evolution, Mechanisms, and Applications2018In: Aboveground–Belowground Community Ecology / [ed] Ohgushi, Takayuki; Wurst, Susanne; Johnson, Scott N., Springer, 2018, p. 85-116Chapter in book (Refereed)
    Abstract [en]

    Our goal within this chapter is to review fungal-mediated above–belowground interactions in which belowground organisms influence aboveground organisms (or vice versa) primarily via a shared host plant, but to also highlight what we feel are the biggest areas for future research within this field: the community approach, stability, evolution, mechanisms, and application of these interactions. First, the community approach examines multiple simultaneously interacting species as communities, an approach that will greatly benefit from the future use of -omics techniques. Examining a greater diversity of interactions (via competition, facilitation, or predation) will likely reveal more varied outcomes that better describe patterns in nature than when individual interactions are considered. Second, we explore the stability of fungal-mediated above–belowground interactions. Given that systems can have multiple stable states influenced by multiple factors, we ask how frequently these interactions occur across stable states. Third, we present three areas in which we expect selection to influence fungal above–belowground interactions: simple (one-way) selective influences of organisms; evolutionary feedbacks and co-evolutionary arms races; and indirect versus direct selective influences. Fourth, we identify mechanisms driving the indirect interactions observed via host plants in fungal-mediated above–belowground interactions and factors influencing their context dependency. Finally, we explore potential applications of these interactions as novel biotechnologies to promote agricultural production, restore natural and degraded habitats, promote ecosystem services, and mitigate against the impacts of climate change.

  • 18.
    Bento, Luiz
    et al.
    University of Federal Rio de Janeiro, Brazil.
    Shizue Moriga Masuda, Laura
    University of Federal Rio de Janeiro, Brazil.
    Bittencourt Peixoto, Roberta
    University of Federal Rio de Janeiro, Brazil.
    Enrich Prast, Alex
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences. University of Federal Rio de Janeiro, Brazil; University of Federal Rio de Janeiro, Brazil.
    Regulation in the Metabolism and Community Structure of a Tropical Salt Flat after Rainfall2017In: Journal of Coastal Research, ISSN 0749-0208, E-ISSN 1551-5036, Vol. 33, no 2, p. 304-308Article in journal (Refereed)
    Abstract [en]

    Tropical salt flats typically lack a water column for most of the year, which means that rainfall is probably one of the major factors that regulate benthic microalgae and metabolism in areas subjected to periodic drought. Therefore, the goal of this study was to evaluate the effects of rainfall on the ecological function and community structure of a tropical mangrove salt flat area. This study showed that the highest primary production and respiration fluxes were recorded on the last day of sampling when it rained (-7.6 and 4.7 mmol C-CO2 m(-2) h(-1), respectively). Net primary production increased significantly compared with the dry period that preceded the rain event. The results also suggested that community structure was regulated by rainfall. After the rain event, abundance increased by one order of magnitude, but the diversity and evenness indices decreased. These results demonstrate that rain does have strong regulatory effects on the ecological function and structure of tropical salt flats.

  • 19.
    Berg, Åke
    et al.
    Swedish University of Agriculture Science, Sweden.
    Bergman, Karl-Olof
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Wissman, Jorgen
    Swedish University of Agriculture Science, Sweden.
    Zmihorski, Michal
    Swedish University of Agriculture Science, Sweden; Polish Academic Science, Poland.
    Ockinger, Erik
    Swedish University of Agriculture Science, Sweden.
    Power-line corridors as source habitat for butterflies in forest landscapes2016In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 201, p. 320-326Article in journal (Refereed)
    Abstract [en]

    Modern intensified agriculture has decreased farmland heterogeneity, which has led to strong negative effects on farmland biodiversity. However, partly forested landscapes seem to offer many alternative habitats for open habitat species such as butterflies, since modern forestry and development of infrastructure has created several new environments such as forest road verges and power-line corridors. The aim of the present study was to investigate the importance of power-line corridors (PLCs) as butterfly habitats by testing i) if species richness and abundance of butterflies in PLCs are affected by adjacent habitat composition (i.e. comparisons of PLCs with different adjacent habitats), ii) if PLCs act as source habitat through spill-over of individuals into adjacent forest roads and semi-natural pastures and iii) if species composition differs among the investigated habitat types. To investigate this we censured the butterfly fauna in 23 study landscapes in south-central Sweden. We found support for the hypothesis that PLCs may act as source habitats for butterflies in forest roads and pastures, since species richness and abundance were decreasing with increasing distance to PLC from 0 to 500 m. In addition, the species composition in forest roads and pastures close to and far from PLCs was similar, suggesting that this increase was not due to an increase of PLC specialists in the other two habitats. Thus, we have shown that PLCs in themselves are important butterfly habitats independently of adjacent habitat composition (adjacent mature forest, clear cuts or arable land), and they contribute to increased species richness and abundance of butterflies in surrounding areas over 10 times larger than their own width. (C) 2016 Elsevier Ltd. All rights reserved.

  • 20.
    Bergfur, Jenny
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Temporal variation in carbon and nitrogen isotope ratios of aquatic biota in two contrasting boreal streams2013In: Fundamental and Applied Limnology, ISSN 1863-9135, Vol. 182, no 3, p. 205-218Article in journal (Refereed)
    Abstract [en]

    Natural abundant isotopes of carbon and nitrogen are frequently used to elucidate food webs and trace energy flows in aquatic ecosystems. Seasonal events such as leaf fall and algal blooms can influence temporal patterns and hence also affect interpretations of isotope data. This study examined such patterns in two contrasting streams in Sweden: Vadsbacken, which is heavily impacted by agriculture and has high nitrogen levels, and Pinnarpsbacken, which has a primarily forested catchment and lower nitrogen levels. Different organic compartments (e.g., detritus, biofilm, and invertebrates) were sampled in September, November, April, and June. Effects of sampling date on isotope signatures of leaf litter (delta N-15: p = 0.0001, delta C-13: p = 0.03), seston (delta N-15: p = 0.001, delta C-13: p = 0.001), FPOM (delta N-15: p = 0.03, delta C-13: p = 0.003), wood (delta C-13: p = 0.05) and invertebrates (delta N-15: p = 0.04) were found. However, there were site-specific temporal patterns in isotope signatures, probably reflecting disparate origins of allochthonous material related to the differences in catchment land use. Mixing models revealed no changes in resource partitioning that could be attributed to the above-mentioned seasonal events. The site-specific patterns recorded here indicate that generalisation regarding ecosystems with different perturbations should be done with caution.

  • 21.
    Bergfur, Jenny
    et al.
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Friberg, Nikolai
    Department of Bioscience, Aarhus University, Silkeborg, Denmark.
    Trade-offs between fungal and bacterial respiration along gradients in temperature, nutrients and substrata: Experiments with stream derived microbial communities2012In: Fungal ecology, ISSN 1754-5048, E-ISSN 1878-0083, Vol. 5, no 1, p. 46-52Article in journal (Refereed)
    Abstract [en]

    We examined the effects of temperature, nutrients and substrata on microbial respiration rates. Leaves of alder and oak were incubated in a natural stream. Leaf discs were incubated in antibiotics to manipulate the ratio of fungi to bacteria with three treatments: antifungal, antibacterial, and combined antifungal and antibacterial treatment in addition to controls. Discs were subsequently incubated in different nutrient set-ups and temperature regimes. Significant effects of temperature, nutrients, microbial treatment and leaf type on respiration rates were found. However, temperature did not significantly add to the effect of eutrophication on microbial respiration rates. A stronger effect of temperature on fungal mediated respiration than on bacterial mediated respiration was found. In streams where leaf litter constitutes the main energy source, fungi constitute the dominant microbial decomposer. Our results indicate that increased temperature due to global warming might have serious implications for ecosystem functioning when leaf litter constitutes the main energy source.

  • 22.
    Bergfur, Jenny
    et al.
    Department of Aquatic Sciences and Assessment, Swedish Agricultural University, Uppsala, Sweden; The Macaulay Land Use Research Institute, Craigiebuckler, Aberdeen, UK .
    Johnson, Richard K
    Department of Aquatic Sciences and Assessment, Swedish Agricultural University, Uppsala, Sweden.
    Sandin, Leonard
    Department of Aquatic Sciences and Assessment, Swedish Agricultural University, Uppsala, Sweden.
    Goedkoop, Willem
    Department of Aquatic Sciences and Assessment, Swedish Agricultural University, Uppsala, Sweden.
    Effects of nutrient enrichment on C and N stable isotope ratios of invertebrates, fish and their food resources in boreal streams2009In: Hydrobiologia, ISSN 0018-8158, E-ISSN 1573-5117, Vol. 628, p. 67-79Article in journal (Refereed)
    Abstract [en]

    Carbon and nitrogen stable isotopes are frequently used to study energy sources and food web structure in ecosystems, and more recently, to study the effects of anthropogenic stress on aquatic ecosystems. We investigated the effect of nutrient enrichment on  d13C and d15N in fine (FPOM), coarse (CPOM) particulate organic matter, periphyton, invertebrates and fish in nine boreal streams in south-central Sweden. In addition, we analysed the diet of benthic consumers using stable isotope data. Increases in d15N of periphyton (R2 = 0.88), CPOM (0.78), invertebrates (0.92) and fish (0.89) were related to nutrient enrichment. In contrast, d13C signatures did not change along the nutrient gradient. Our results show that d15N has potential as a sensitive indicator of nutrient enrichment in boreal streams. Carbon and nitrogen isotopes failed to elucidate putative diets of selected aquatic consumers. Indeed, comparison of low- and high-impact sites showed that d13C of many consumers were found outside the ranges of basal resource d13C. Moreover, ranges of basal resource d13C and d15N overlapped at both low and high sites, making discrimination between the importance of allochthonous and autochthonous production difficult. Our findings show that a fractionation rate of 3.4% is not always be appropriate to assess trophic interactions, suggesting that more studies are needed on fractionation rates along gradients of impairment.

  • 23.
    Berglund, Hilda-Linn
    Linköping University, Department of Physics, Chemistry and Biology.
    Effects of flower abundance and colour on pan-trap catches2016Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [sv]

    Pollinating insects are important for many plants and for the human population. To be able to monitor pollinators and assess improvements made for them, it is important to get information about pollinator population changes. Therefore, it is essential that the methods used to collect data are accurate (i.e. that they represent the pollinator fauna). One commonly used method is pan-traps, but this method is suggested to be affected by the abundance of surrounding flowers. The results in the present study showed that catches in pan-traps can be affected by flower cover and the colour of the flowers, depending on which colours are preferred by the insects. The effects differed when looking at a larger scale (2-6 ha) and a smaller scale (25 m2) around the pan-traps. When comparing cover of flowers with catches in pan-traps in the small scale there were some results that showed linear positive correlations (expected), but also, negative linear and quadratic correlations. In contrast, in the large scale there were no significant positive linear correlations. When comparing catches in hand-net and pan-traps, only in one out of six taxonomical groups there were a correlation. The results in this study show that catches in pan-traps can be misleading if catches are done to survey pollinator population fauna and the cover of flowers is not considered.

  • 24.
    Bergman, Karl-Olof
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Daniel Ferreira, Juliana Daniel
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. Swedish Univ Agr Sci, Sweden.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Ockinger, Erik
    Swedish Univ Agr Sci, Sweden.
    Westerberg, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Butterflies in Swedish grasslands benefit from forest and respond to landscape composition at different spatial scales2018In: Landscape Ecology, ISSN 0921-2973, E-ISSN 1572-9761, Vol. 33, no 12, p. 2189-2204Article in journal (Refereed)
    Abstract [en]

    ContextLoss and fragmentation of semi-natural grasslands has critically affected many butterfly species in Europe. Habitat area and isolation can have strong effects on the local biodiversity but species may also be strongly affected by the surrounding matrix.ObjectivesWe explored how different land cover types in the landscape explained the occurrence of butterfly species in semi-natural grasslands.MethodsUsing data from 476 semi-natural grasslands in Sweden, we analysed the effect of matrix composition on species richness and occurrence. Additionally, we analysed at which spatial scales butterflies responded to matrix types (forests, semi-natural grasslands, arable land and water).ResultsForest cover showed the strongest positive effect on species richness, followed by semi-natural grasslands. Forest also had a positive effect on red-listed species at local scales. Responses to matrix composition were highly species-specific. The majority of the 30most common species showed strong positive responses to the amount of forest cover within 200-500m. There was a smaller group of species showing a positive response to arable land cover within 500-2000m. Thirteen species showed positive responses to the amount of semi-natural grasslands, generally at larger scales (10-30km).ConclusionsOur study showed that surrounding forest is beneficial for many grassland butterfly species and that forests might mitigate the negative effects of habitat loss caused by agricultural intensification. Also, semi-natural grasslands were an important factor for species richness at larger spatial scales, indicating that a landscape consisting mainly of supporting habitats (i.e. forests) are insufficient to sustain a rich butterfly fauna.

  • 25.
    Bergner, Adam
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Studier av habitatval och revirstrukturer hos vassångare (Locustella luscinioides) i Tåkern2012Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    The Savi’s Warbler (Locustella luscinioides) is a recently established bird species in a few reedy shallow lakes of southern Sweden and has only been found nesting for the last twenty years. Little is known about the species' habitat preferences, breeding biology and demands for specific territory structures at breeding sites in Sweden. Knowledge of a newly established species’ habitat requirements is essential to maintain a viable population and design action plans. This study, the first of its kind in Sweden, examined the vegetation structures in occupied territories of Savi’s Warblers at Lake Tåkern, the country's stronghold for the species. The species was found to be associated with the outer edge zones and fragmented areas of reed (Phragmites australis). Occupied territories differed from randomly chosen unoccupied (control) territories by having a thicker layer of reed litter, and on average more bushes of Willow (Salix spp.) present. Reed density and reed height did not differ from areas that lacked Savi’s Warblers. Territorial and displaying males were concentrated in two edge areas with a mosaic of reed islets where the territories remained relatively close together.

  • 26.
    Bergstedt, Johan
    Linköping University, Department of Physics, Measurement Technology, Biology and Chemistry. Linköping University, The Institute of Technology.
    Boreal vegetation responses to forestry as reflected in field trial and survey data2004Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis had two objectives: the first objective was to evaluate the response of forest ground vegetation to selected forestry operations, i.e. cutting of different intensities and scarification; the second objective was to compare the use of survey data in vegetation research with that of more traditional research using field trials - i.e. can survey data be used and produce results that comply with those emerging from field trials? Here, the results from an analysis of survey data has been compared with results emerging from a field trial.

    Survey data was analysed from the National Forest Inventory (NFI), using 789 sample plots in central and northern Sweden visited twice at an interval of 10-11 years, 294 of which had been subjected to logging between inventories. This was compared with a field trial in central Sweden: a complete block design with four replicates - three treatments and conventional harvesting as the control.

    The cutting intensity was found to have an impact on the ground-layer flora, the change being mostly differences in abundance rather than change in species richness. Those increasing were early successional species, i.e. crustose lichens, Deschampsia flexuosa. In contrast, Vaccinium myrtillus was decreasing substantially in response to increased cutting intensity. A number of species appeared to be indifferent to cutting, i.e. Vaccinium vitisidaea, Trientalis europaea.

    Scarification had a different impact on the flora than cutting: only Polytrichum spp. increased substantially, while many decreased.

    For those effects that were possible to compare in both studies, the results from survey data comply with those from the field trial, indicating that survey data is possible to use in forest vegetation research.

  • 27.
    Bergstedt, Johan
    Linköping University, Department of Physics, Chemistry and Biology, Ecology . Linköping University, The Institute of Technology.
    Boreal vegetation responses to forestry as reflected in field trial and survey data and the quality of cover estimates and presence/absence in vegetation inventory2008Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis has two main focuses; first, the response of forest ground layer flora on forestry, mainly harvesting and secondly, the quality of the vegetation assessment methods, cover estimates by eye and presence/absence data.

    The effect of harvesting intensity was evaluated with survey data from permanent plots as well as vegetation data from a field trial fourteen years after harvesting. Both data sets confirmed that response of ground layer flora increased with increasing logging intensity. Thereby, indicating that survey data is possible to use in research. From the survey data set, existence of a time lag was evident for several species and also a threshold level was evident in cutting intensity needed to affect a number of species. Logging had a modest, but significant positive effect on the change in species number per plot. Species turnover was influenced by the proportion of Picea abies in the tree canopy; site productivity; and logging intensity. In the field trial scarification had a strong effect that was different from the one created by cutting.

    In plant ecology cover estimate by eye and presence/absence recording are the two most frequent methods used. The methods were evaluated with survey data and a field trial.

    In the first data set vegetation was recorded independently by two observers in 342 permanent 100-m2 plots. Overall, one third of each occurrence was missed by one of the two observers, but with large differences among species. Species occurring at low abundance tended to be frequently overlooked. Observer-explained variance in cover estimates was <10% in 15 of 17 species.

    In the second data set, 10 observers independently estimated cover in sixteen 100-m2 plots in two different vegetation types. The bias connected to observer varied substantially between species. The estimates of missing field and bottom layer had the highest bias, indicating that missing layers are problematic to use in analysis of change. Experience had a surprisingly small impact on the bias connected to observer. Analyses revealed that for the statistical power, cover estimates by eye carries a higher information value than do presence/absence data when distinguishing between vegetation types, differences between observers is negligible, and using more than one observer had little effect.

    List of papers
    1. The impact of logging intensity on field-layer vegetation in Swedish boreal forests
    Open this publication in new window or tab >>The impact of logging intensity on field-layer vegetation in Swedish boreal forests
    2001 (English)In: Forest Ecology and Management, ISSN 0378-1127, Vol. 154, no 1-2, p. 105-115Article in journal (Refereed) Published
    Abstract [en]

    The relationship between logging intensity and changes in ground cover vegetation was studied in 16 species and groups of species recorded at 10- or 11-year intervals in mature conifer-dominated forests. The 789 plots located in northern and central Sweden had been surveyed by the National Forest Inventory and the National Survey of Forest Soil and Vegetation. Thirty-seven percent of the plots had been subjected to a thinning or clear-cutting between the inventories. A principal components analysis showed that, of the variables considered, logging intensity had the highest explanatory power regarding change in ground cover vegetation between the inventories (the other variables were sum of temperatures, age of stand, timber volume, percentage Pinus sylvestris and site productivity). A multivariate direct gradient analysis technique (Redundancy analysis) showed that the logging intensity significantly affected the change in cover. This analysis also ranked the species in their responsiveness to logging. Epilobium angustifolium, narrow-leaved grasses and broad-leaved grasses, increased most with logging intensity. The response was not linear and only detectable at high logging intensities (>80%). In contrast, Vaccinium myrtillus seemed to decrease linearly with increased logging intensity. There was several years time-lag in the response to logging of E. angustifolium, V. myrtillus and narrow-leaved grasses. Several species and groups of species seemed unaffected by the logging. In sample plots unaffected by logging the cover of most species decreased.

    Keywords
    Clear cut, Community, Cutting, Multivariate analysis, Sweden, Thinning
    Identifiers
    urn:nbn:se:liu:diva-13278 (URN)10.1016/S0378-1127(00)00642-3 (DOI)
    Available from: 2008-05-07 Created: 2008-05-07 Last updated: 2018-07-03
    2. Composition of vegetation after a modified harvesting and propagation method compared with conventional clear-cutting, scarification and planting: evaluation 14 years after logging
    Open this publication in new window or tab >>Composition of vegetation after a modified harvesting and propagation method compared with conventional clear-cutting, scarification and planting: evaluation 14 years after logging
    2008 (English)In: Applied Vegetation Science, ISSN 1402-2001, Vol. 11, no 2, p. 159-168Article in journal (Refereed) Published
    Abstract [en]

    Question: How does the vegetation of boreal forests respond to harvesting and scarification?

    Location: 650 m a.s.l., central Sweden (61°38' N).

    Methods: The response of boreal forest vegetation to cutting and scarification was studied in a field trial, which consisted of three treatments plus conventional harvesting as a control in a complete block design with four replicates. The cutting was done 14 years prior to vegetation inventory and scarification and planting were conducted the first or second years after cutting.

    Results: The species most abundant at higher cutting intensities were crustose lichens, Cladonia spp., Cladina arbuscula, Polytrichum spp. and pioneer mosses, the grass Deschampsia flexuosa, and the tree Betula pubescens, A few species had substantially lower abundance in treatments with higher cutting intensity, notably Hylocomium splendens and Vaccinium myrtillus. Scarification had a strong effect that was different from the one created by cutting. In scarification treatments, Polytrichum spp. were the only species with high abundance; most species had low abundance, i.e. Barbilophozia lycopodioides, Vaccinium vitis-idaea, Pleurozium schreberi, Carex globularis, Empetrum nigrum, Cladina arbuscula, Sphagnum spp.

    Conclusions: Our results elaborate on the details of the well-known effect of cutting on ground-layer flora, and also give support for the profound and long-lasting effect that soil scarification has on forest vegetation.

    Keywords
    Boreal forest, Cutting intensity, Field trial, Forest understorey, Logging, Propagation, Sweden
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-13279 (URN)10.3170/2007-7-18343 (DOI)
    Available from: 2008-05-07 Created: 2008-05-07 Last updated: 2014-10-08
    3. Turnover of ground layer species in Swedish boreal forests and its response to logging
    Open this publication in new window or tab >>Turnover of ground layer species in Swedish boreal forests and its response to logging
    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:liu:diva-13280 (URN)
    Available from: 2008-05-07 Created: 2008-05-07 Last updated: 2010-01-13
    4. Systematic and random variation in vegetation monitoring data
    Open this publication in new window or tab >>Systematic and random variation in vegetation monitoring data
    Show others...
    2008 (English)In: Journal of Vegetation Science, ISSN 1100-9233, E-ISSN 1654-1103, Vol. 19, p. 633-644Article in journal (Refereed) Published
    Abstract [en]

    Question: Detecting species presence in vegetation and making visual assessment of abundances involve a certain amount of skill, and therefore subjectivity. We evaluated the magnitude of the error in data, and its consequences for evaluating temporal trends.

    Location: Swedish forest vegetation.

    Methods: Vegetation data were collected independently by two observers in 342 permanent 100-m2 plots in mature boreal forests. Each plot was visited by one observer from a group of 36 and one of two quality assessment observers. The cover class of 29 taxa was recorded, and presence/absence for an additional 50.

    Results: Overall, one third of each occurrence was missed by one of the two observers, but with large differences among species. There were more missed occurrences at low abundances. Species occurring at low abundance when present tended to be frequently overlooked. Variance component analyses indicated that cover data on 5 of 17 species had a significant observer bias. Observer-explained variance was < 10% in 15 of 17 species.

    Conclusion: The substantial number of missed occurrences suggests poor power in detecting changes based on presence/absence data. The magnitude of observer bias in cover estimates was relatively small, compared with random error, and therefore potentially analytically tractable. Data in this monitoring system could be improved by a more structured working model during field work.

    Place, publisher, year, edition, pages
    Institutionen för fysik, kemi och biologi, 2008
    Keywords
    Forest, Observer error, Permanent plot, Statistical power, Sweden
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-11872 (URN)10.3170/2008-8-18423 (DOI)
    Note
    Original publication: Milberg, P., Bergstedt, J., Fridman, J., Odell, G & Westerberg, L., Systematic and random variation in vegetation monitoring data, 2008, Journal of Vegetation Science, (19), 633-644. http://dx.doi.org/10.3170/2008-8-18423. Copyright: Opulus Press, http://www.opuluspress.se/index.phpAvailable from: 2008-05-22 Created: 2008-05-22 Last updated: 2017-12-13
    5. In the eye of the beholder: bias and stochastic variation in cover estimates
    Open this publication in new window or tab >>In the eye of the beholder: bias and stochastic variation in cover estimates
    Manuscript (Other academic)
    Identifiers
    urn:nbn:se:liu:diva-13282 (URN)
    Available from: 2008-05-07 Created: 2008-05-07 Last updated: 2010-01-13
  • 28.
    Bergstedt, Johan
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Axelsson, Anna-Lena
    SLU Umeå.
    Karlsson, Jesper
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Lönander, Johanna
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Törnqvist, Lina
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Förändringar i Eklandskapet 1927 till 2013: i den första riksskogstaxeringens fotspår2017In: Svensk Botanisk Tidskrift, ISSN 0039-646X, Vol. 111, no 6, p. 331-343Article in journal (Refereed)
    Abstract [en]

    Transects covering 90 km inan area south of Linköping in the province of Östergötland, SE Sweden, were relocated and reinventoried in 2013 using the same methodology as in the first national forest inventory of 1927. Data for land-use, forest type and species-specific tree sizes were obtained and compared with values from 1927. The results show that arable fields and pastures have decreased, while forests and areas covered by roads etc. have increased considerably. Picea abies has increased more than Pinus sylvestris. The reasons for the changes are discussed.

  • 29.
    Bidleman, Terry
    et al.
    Umeå universitet, Sweden.
    Kucklick, John
    National Institute of Standards and Technology, South Carolina, USA.
    Letcher, Robert
    National Wildlife Research Centre, Canada.
    Jantunen, Liisa
    Environment and Climate Change, Canada.
    Wong, Fiona
    Environment and Climate Change, Canada.
    Kylin, Henrik
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    CONTAMINANTS OF EMERGING CONCERN IN THE ARCTIC: AN ASSESSMENT OF HALOGENATED NATURAL PRODUCTS2016In: Organohalogen Compounds, ISSN 1026-4892, Vol. 78, p. 193-196, article id 8.4010Article in journal (Refereed)
  • 30.
    Birgersson, Sabina
    Linköping University, Department of Physics, Chemistry and Biology.
    Personality assessment and interactions in eight captive bottlenose dolphins (Tursiops truncatus)2011Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    In recent years there has been an increased interest in measuring animal personality. It is argued that personality in animals is expressed through the behaviours they display. In this study personality has been investigated in a group of eight captive bottlenose dolphins (Tursiops truncatus). Data from focal samplings were analysed by using behavioural codings and the Five-factor model consisting of Openness to experience, Conscientiousness, Extraversion, Agreeableness and Neuroticism. The results revealed that the dolphins display both distinct personality differences as well as similarities in these factors. By calculating coefficients of association it was found that the dolphins also prefer the company of certain individuals over others. Knowledge of individual personality differences and its implications can be helpful in aspects such as management and reintroduction programs, evolution and genetics and in providing a complementary perspective to explain other behavioural and cognitive studies.

  • 31.
    Bouwman, Henk
    et al.
    North-West University, South Africa.
    Kylin, Henrik
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Louette, Michel
    Royal Museum for Central Africa, Belgium.
    Using ringing data to update the continental distributions of the subspecies of the Lesser Black-Backed Gull2012In: Afring News, ISSN 2222-341X, Vol. 41, p. 13-15Article in journal (Refereed)
  • 32.
    Bouwman, Hindrik
    et al.
    North West University, South Africa .
    Kylin, Henrik
    Linköping University, The Tema Institute, Department of Water and Environmental Studies. Linköping University, Faculty of Arts and Sciences.
    Sun Choong Kwet Yive, Nee
    Mauritian Wildlife Fdn, Mauritius .
    Loken, Katharina
    Norwegian School Vet Science, Norway .
    Utne Skaare, Janneche
    Norwegian School Vet Science, Norway .
    Polder, Anuschka
    Norwegian School Vet Science, Norway .
    First report of chlorinated and brominated hydrocarbon pollutants in marine bird eggs from an oceanic Indian Ocean island2012In: Environmental Research, ISSN 0013-9351, E-ISSN 1096-0953, Vol. 118, p. 53-64Article in journal (Refereed)
    Abstract [en]

    We report for the first time levels of persistent organic pollutants in marine bird eggs from an oceanic island in the Indian Ocean, the worlds third largest ocean. Ten eggs each of the Common Noddy, also known as the Brown Noddy (Anous stolidus), and Sooty Tern (Sterna fuscata) were collected from Ile Cocos off the coast of the island of Rodrigues, located 560 km east of the island of Mauritius. Sigma PCBs had the highest levels (2.2 and 2.6 ng/g wm, wet mass; 20 and 19 ng/g lm, lipid mass) for common Noddy and Sooty Tern, respectively (and following), then Sigma DDT (1.9 and 3.1 ng/g wm; 17 and 23 ng/g lm), and mirex (0.96 and 0.69 ng/g wm; 8.7 and 5.0 ng/g lm). Sigma Chlordanes (0.094 and 0.15 ng/g wm; 0.48 and 0.73 ng/g lm) and Sigma toxaphenes (0.26 and 0.61 ng/g wm; 2.4 and 5.9 ng/g lm) are rare data for these compounds from this ocean. Brominated flame retardants were low (0.08 and 0.07 ng/g wm; 0.7 and 0.7 ng/g lm). Multivariate analyses indicated different contamination patterns in the prey items as Sooty Terns had significantly higher levels of mean Sigma chlordanes and Sigma toxaphenes, as well as CB105, -108 and -157. p,p-DDE had an association with thinner eggshells in the Sooty Tern. Although the contaminant levels were in all respects low, industrialisation, development on the periphery, commercial exploitation of the marine environment, and pollutants transferred over long distances by marine debris is likely to add to chemical pressure in this region. Monitoring changes in background levels of pollutants in remote regions will indicate such trends, and marine bird eggs from Rodrigues would be an excellent site.

  • 33.
    Brengdahl, Martin
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Differentiation of dispersive traits under a fluctuating range distribution in Asellus aquaticus2014Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    Knowledge about dispersion is of utmost importance for understanding populations’ reaction to changes in the environment. Expansion of a population range brings with it both spatial sorting and over time, spatial selection. This means that dispersion rates increases over time at the expanding edge. Most studies have so far been performed on continuously expanding populations. This study aims to bring more knowledge about dispersal biology in dynamic systems. I studied dispersal traits in two permanent and two seasonal vegetation habitats of an isopod (Asellus aquaticus), for which differentiation between habitat types has previously been shown. I quantified differences in displacement (dispersal rate) and three morphological traits, head angle (body streamline) and leg of the third and seventh pair of legs. Isopods from the seasonal vegetation had higher displacement rates than animals from permanent vegetation. This inclines that mechanisms driving spatial selection in expanding population ranges also exist in dynamic systems. The more streamlined isopods found in seasonal sites further points towards spatial sorting by dispersion capability. Because no effect of permanence was found on leg length and there was no correlation between streamlining and displacement, the higher dispersion among animals from seasonal habitats most likely derives from behavioral differences.

  • 34.
    Brengdahl, Martin
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Dispersive trait expression of Asellus aquaticus from a rare cave habitat2016Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Dispersal influences several ecological and evolutionary processes, such as intraspecific competition, genetic drift and inbreeding. It can lead to phenotypic mismatch with the habitat when a locally adapted individual winds up in an environment with a divergent selection regime compared to the source habitat. The aim of this project was to compare dispersive traits in the freshwater isopod Asellus aquaticus from a cave habitat, with surface dwelling isopods collected upstream and downstream from the cave system. The subterranean stream (cave) represents a rare, geographically limited habitat which has a divergent selective pressure compared to the surrounding habitats. Experiments on dispersal were performed in the laboratory, in darkness with IR-equipment for visualization. Displacement was measured using one-dimensional test arenas. Compared to the surface phenotype, the cave phenotype was expected to have reduced fitness outside of the cave and unlikely to successfully disperse to new areas of similar suitable conditions. The results did not follow my main hypothesis that isopods from the cave would be less dispersive than individuals from the surface. The inconclusive results might derive from large variation in the data and divergent adaptations which yield similar expression of dispersal.

  • 35.
    Brose, Ulrich
    et al.
    German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103, Leipzig, Germany 2 Faculty of Biology and Pharmacy, Institute of Ecology, Friedrich Schiller University Jena, 07743, Jena, Germany.
    Blanchard, Julia L.
    Institute for Marine and Antarctic Studies and Centre for Marine Socioecology, University of Tasmania, 20 Castray Esplanade, Battery Point TAS 7004 Australia.
    Eklöf, Anna
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering.
    Galiana, Nuria
    Ecological Networks and Global Change Group, Experimental Ecology Station, Centre National de la Recherche Scientifique, 09200, Moulis, France.
    Hartvig, Martin
    Center for Macroecology, Evolution and Climate, Natural History Museum of Denmark, University of Copenhagen, DK-2100, Copenhagen, Denmark 7 National Institute of Aquatic Resources, Technical University of Denmark, DK-2920, Charlottenlund, Denmark 8 Systemic Conservation Biology Group, J.F. Blumenbach Institute of Zoology and Anthropology, Georg-August University of Göttingen, 37073, Göttingen, Germany.
    Hirt, Myriam R.
    German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103, Leipzig, Germany 2 Faculty of Biology and Pharmacy, Institute of Ecology, Friedrich Schiller University Jena, 07743, Jena, Germany.
    Kalinkat, Gregor
    Department of Biology and Ecology of Fishes, Leibniz-Institute of Freshwater Ecology and Inland Fisheries, 12587, Berlin, Germany 10 Department of Fish Ecology and Evolution, Eawag, 6047, Kastanienbaum, Switzerland.
    Nordström, MArie C.
    Environmental and Marine Biology, Åbo Akademi University, FI-20520, Åbo, Finland.
    O'Gorman, Eoin J.
    Imperial College London, Silwood Park Campus, Buckhurst Road, Ascot, Berkshire, SL5 7PY, UK.
    Rall, Björn C.
    German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103, Leipzig, Germany 2 Faculty of Biology and Pharmacy, Institute of Ecology, Friedrich Schiller University Jena, 07743, Jena, Germany.
    Schneider, Florian D.
    Institut des Sciences de l’Evolution, Universit´e Montpellier, CNRS, IRD, EPHE, CC065, 34095, Montpellier Cedex 05, France.
    Thébault, Elisa
    Institute of Ecology and Environmental Sciences - Paris, UMR 7618 (UPMC, CNRS, IRD, INRA, UPEC, Paris Diderot), Universit´e Pierre et Marie Curie, 75005, Paris, France.
    Jacob, Ute
    Department of Biology, Institute for Hydrobiology and Fisheries Science, Center for Earth System Research and Sustainability (CEN), KlimaCampus, University of Hamburg, 22767, Hamburg, Germany.
    Predicting the consequences of species lossusing size-structured biodiversity approaches2017In: Biological Reviews, ISSN 1464-7931, E-ISSN 1469-185X, Vol. 92, no 2, p. 684-697Article, review/survey (Refereed)
    Abstract [en]

    Understanding the consequences of species loss in complex ecological communities is one of the great challenges in current biodiversity research. For a long time, this topic has been addressed by traditional biodiversity experiments. Most of these approaches treat species as trait-free, taxonomic units characterizing communities only by species number without accounting for species traits. However, extinctions do not occur at random as there is a clear correlation between extinction risk and species traits. In this review, we assume that large species will be most threatened by extinction and use novel allometric and size-spectrum concepts that include body mass as a primary species trait at the levels of populations and individuals, respectively, to re-assess three classic debates on the relationships between biodiversity and (i) food-web structural complexity, (ii) community dynamic stability, and (iii) ecosystem functioning. Contrasting current expectations, size-structured approaches suggest that the loss of large species, that typically exploit most resource species, may lead to future food webs that are less interwoven and more structured by chains of interactions and compartments. The disruption of natural body-mass distributions maintaining food-web stability may trigger avalanches of secondary extinctions and strong trophic cascades with expected knock-on effects on the functionality of the ecosystems. Therefore, we argue that it is crucial to take into account body size as a species trait when analysing the consequences of biodiversity loss for natural ecosystems. Applying size-structured approaches provides an integrative ecological concept that enables a better understanding of each species' unique role across communities and the causes and consequences of biodiversity loss.

  • 36.
    Brose, Ulrich
    et al.
    Technical University of Darmstadt, Germany.
    Pavao-Zuckerman, Mitchell
    University of Arizona, Tucson, Arizona, USA.
    Eklöf, Anna
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, The Institute of Technology.
    Bengtsson, Janne
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Berg, Matty P.
    Vrije Universiteit Amsterdam, The Netherlands.
    Cousins, Steven H.
    Cranfield University, United Kingdom.
    Mulder, Christian
    National Institute for Public Health and the Environment (RIVM), Bilthoven, The Netherlands.
    Verhoef, Herman A.
    Vrije Universiteit Amsterdam, The Netherlands.
    Wolters, Volkmar
    Justus-Liebig-University, Giessen, Germany.
    Spatial aspects of food webs2005In: Dynamic Food Webs: Multispecies Assemblages, Ecosystem Development and Environmental Change / [ed] P.C. deRuiter, V. Wolters & J.C. Moore, London, UK: Elsevier, 2005, Vol. 3, p. 463-469Conference paper (Refereed)
    Abstract [en]

    Aspects of spatial scale have until recently been largely ignored in empirical and theoretical food web studies (e.g., Cohen & Briand 1984, Martinez 1992, but see Bengtsson et al. 2002, Bengtsson & Berg, this book). Most ecologists tend to conceptualize and represent food webs as static representations of communities, depicting a community assemblage as sampled at a particular point in time, or highly aggregated trophic group composites over broader scales of time and space (Polis et al. 1996). Moreover, most researchers depict potential food webs, which contain all species sampled and all potential trophic links based on literature reviews, several sampling events, or laboratory feeding trials. In reality, however, not all these potential feeding links are realized as not all species co-occur, and not all samples in space or time can contain all species (Schoenly & Cohen 1991), hence, yielding a variance of food web architecture in space (Brose et al. 2004). In recent years, food web ecologists have recognized that food webs are open systems – that are influence by processes in adjacent systems – and spatially heterogeneous (Polis et al. 1996). This influence of adjacent systems can be bottom-up, due to allochthonous inputs of resources (Polis & Strong 1996, Huxel & McCann 1998, Mulder & De Zwart 2003), or top-down due to the regular or irregular presence of top predators (e.g., Post et al. 2000, Scheu 2001). However, without a clear understanding of the size of a system and a definition of its boundaries it is not possible to judge if flows are internal or driven by adjacent systems. Similarly, the importance of allochthony is only assessable when the balance of inputs and outputs are known relative to the scale and throughputs within the system itself. At the largest scale of the food web – the home range of a predator such as wolf, lion, shark or eagle of roughly 50 km2 to 300 km2 –the balance of inputs and outputs caused by wind and movement of water may be small compared to the total trophic flows within the home range of the large predator (Cousins 1990). Acknowledging these issues of space, Polis et al (1996) argued that progress toward the next phase of food web studies would require addressing spatial and temporal processes. Here, we present a conceptual framework with some nuclei about the role of space in food web ecology. Although we primarily address spatial aspects, this framework is linked to a more general concept of spatio-temporal scales of ecological research.

  • 37.
    Bröms Axelsson, Emilia
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Do we protect the right forests? – A case study of representativeness of protected forests in Östergötland, Sweden, and identification of tracts of value.2015Independent thesis Advanced level (degree of Master (One Year)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Protected forests need to be a representative selection of the natural proportion of forest types, including distribution of productivity levels, age classes and nature types This is important for the possibility to preserve biodiversity. In addition, the protected areas has to be of sufficient size and not isolated from each other, to function as effective biodiversity preservers. The question is, how does it look in reality? The objective with this study was to get an overall picture of the current forest protection situation in Östergötland, Sweden, and how it has changed the last 60 years. Are all ecologically relevant forest habitat types represented in appropriate proportions in protected forests? To evaluate where the protected areas are located in relation to each other, a connectivity index was calculated for each patch of protected area. Together with a value for size, a value index was created and applied to all protected areas, and it turns out that the protected areas of Östergötland is not totally representative when it comes to nature types, age classes and levels of productivity.For example, there is an underrepresentation of both pine and spruce forests on high-productivity soils. However, areas with higher productivity levels have been protected over time. The age distribution seems to be skewed towards older forests in protected areas. There are some underrepresented nature types, as well as overrepresented ones in nature reserves, a small overrepresentation of unproductive impediments, and only spruce and mixed forests seems well connected in the landscape. The greatest differences in protected and unprotected forests is the productivity level, were focus should be on protecting higher productivity areas in order to succeed in preserving the biodiversity of forests as intended.

  • 38.
    Bröms Axelsson, Emilia
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Kloridutlakning från flygaska: möjligheten till en lokal hantering2014Independent thesis Basic level (degree of Bachelor), 180 HE creditsStudent thesis
    Abstract [en]

    In Sweden, there are limits to how much leachable substances waste must contain in order to be deposited as hazardous waste. Fly ash from waste incineration often end up over the limit, mainly due to the chloride content. Fly ash is therefore often deposited abroad. The purpose of this study was to investigate the possibility to handle fly ash locally. To clarify how the law is applied, environmental reports and permit documents from ten waste sites with permission to deposit fly ash were studied. In addition, a literature study was made to review the state of knowledge regarding the treatments of fly ash. The treatment methods are numerous, but are at different levels of commerciality. Among the treatments available there are both physical, chemical, biological, electrical and thermal variants. Many of the treatments (except for carbonation and microbial bioleaching) results in chloride levels below the limits. Several are however unrealistically expensive or generate wastewater with high levels of chloride that would need further treatment. Three plants out of the ten holding permits to deposit fly ash, have exemptions from the limit for chlorides. It's however difficult to see a common reasoning for allowing exemptions. In several cases there are sensitive receiving waters downstream from the landfill. One reason to be dispensed despite this sensitivity, may be the guidance that EPA issued. It is not formulated any specific concerns relating to chlorides. One handles therefore often high levels of chloride in the leachate as a dilution problem, not a leaching problem.

  • 39.
    Brüsin, Martin
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, The Institute of Technology.
    Influence of landscape scale and habitat distribution on individual bat species and bat species richness2013Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Habitat fragmentation is one of the most important factors affecting species extinction and biodiversity loss, Species habitat response expects to differ with habitat feature at different spatial scales and this study was to identify how bat diversity and individual bat species respond to different habitat amounts. The local bat species richness was observed in 156 different locations in Östergötland and the proportion of different habitats were calculated for circular areas with diameters ranging from 400 m. to 12 km. from each location. Although we found that the individual bat species responded differently to the amount of each habitat at different spatial scales, the bat species richness showed a decreasing response with increasing spatial scale. The strongest response of bat species richness to habitat characteristics was at a scale of 939 m.

  • 40.
    Burman, Joseph
    et al.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, 230 53 Alnarp, Sweden/Ecology Research Group, Canterbury Christ Church University, Canterbury, Kent, CT1 1QU, England, UK .
    Westerberg, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Ostrow, Suzanne
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Ryrholm, Nils
    University of Gävle, 801 76 Ga¨vle, Sweden.
    Bergman, Karl-Olof
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Winde, Inis
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences,Alnarp, Sweden, Department of Biology, Lund University, So¨lvegatan 37, 223 62 Lund, Sweden.
    Nyabuga, Franklin N.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, 230 53 Alnarp, Sweden, Department of Biology, Lund University, So¨lvegatan 37, 223 62 Lund, Sweden.
    Larsson, Mattias C.
    Department of Plant Protection Biology, Swedish University of Agricultural Sciences, Box 102, 230 53 Alnarp, Sweden.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Revealing hidden species distribution with pheromones: the caseof Synanthedon vespiformis (Lepidoptera: Sesiidae) in Sweden2016In: Journal of Insect Conservation, ISSN 1366-638X, E-ISSN 1572-9753, Vol. 20, no 1, p. 11-21Article in journal (Refereed)
    Abstract [en]

    Synanthedon vespiformis L. (Lepidoptera:Sesiidae) is considered a rare insect in Sweden, discoveredin 1860, with only a few observations recorded until a sexpheromone attractant became available recently. This studydetails a national survey conducted using pheromones as asampling method for this species. Through pheromonetrapping we captured 439 specimens in Southern Sweden at77 sites, almost tripling the number of previously reportedrecords for this species. The results suggest that S. vespiformisis truly a rare species with a genuinely scattereddistribution, but can be locally abundant. Habitat analyseswere conducted in order to test the relationship betweenhabitat quality and the number of individuals caught. InSweden, S. vespiformis is thought to be associated with oakhosts, but our attempts to predict its occurrence by theabundance of oaks yielded no significant relationships. Wetherefore suggest that sampling bias and limited knowledgeon distribution may have led to the assumption that thisspecies is primarily reliant on oaks in the northern part ofits range, whereas it may in fact be polyphagous, similar toS. vespiformis found as an agricultural pest in Central andSouthern Europe. We conclude that pheromones canmassively enhance sampling potential for this and otherrare lepidopteran species. Large-scale pheromone-basedsurveys provide a snapshot of true presences and absencesacross a considerable part of a species national distributionrange, and thus for the first time provide a viable means ofsystematically assessing changes in distribution over timewith high spatiotemporal resolution.

  • 41.
    Bélteky, Johan
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Agnvall, Beatrix
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Johnsson, Martin
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Wright, Dominic
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Jensen, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Domestication and tameness: brain geneexpression in red junglefowl selected for less fear of humans suggests effects on reproduction and immunology2016In: Royal Society Open Science, E-ISSN 2054-5703, no 3, article id 160033Article in journal (Refereed)
    Abstract [en]

    The domestication of animals has generated a set of phenotypicmodifications, affecting behaviour, appearance, physiologyand reproduction, which are consistent across a range ofspecies. We hypothesized that some of these phenotypes couldhave evolved because of genetic correlation to tameness,an essential trait for successful domestication. Starting froman outbred population of red junglefowl, ancestor of alldomestic chickens, we selected birds for either high or lowfear of humans for five generations. Birds from the fifthselected generation (S5) showed a divergent pattern of growthand reproduction, where low fear chickens grew larger andproduced larger offspring. To examine underlying geneticmechanisms, we used microarrays to study gene expressionin thalamus/hypothalamus, a brain region involved in fearand stress, in both the parental generation and the S5. Whileparents of the selection lines did not show any differentiallyexpressed genes, there were a total of 33 genes with adjustedp-values below 0.1 in S5. These were mainly related to spermfunction,immunological functions, with only a few known tobe relevant to behaviour. Hence, five generations of divergentselection for fear of humans produced changes in hypothalamicgene expression profiles related to pathways associated withmale reproduction and to immunology. This may be linked to the effects seen on growth and size of offspring. These results support the hypothesis thatdomesticated phenotypes may evolve because of correlated effects related to reduced fear of humans.

  • 42.
    Carlen, Ida
    et al.
    AquaBiota Water Res, Sweden; Stockholm Univ, Sweden.
    Thomas, Len
    Univ St Andrews, Scotland.
    Carlstrom, Julia
    AquaBiota Water Res, Sweden; Swedish Museum Nat Hist, Sweden.
    Amundin, Mats
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. Kolmarden Wildlife Pk, Sweden.
    Teilmann, Jonas
    Aarhus Univ, Denmark.
    Tregenza, Nick
    Chelonia Ltd, England.
    Tougaard, Jakob
    Aarhus Univ, Denmark.
    Koblitz, Jens C.
    German Oceanog Museum, Germany; Max Planck Inst Ornithol, Germany; Univ Constance, Germany.
    Sveegaard, Signe
    Aarhus Univ, Denmark.
    Wennerberg, Daniel
    Kolmarden Wildlife Pk, Sweden.
    Loisa, Olli
    Turku Univ Appl Sci, Finland.
    Daehne, Michael
    German Oceanog Museum, Germany.
    Brundiers, Katharina
    German Oceanog Museum, Germany.
    Kosecka, Monika
    Univ Gdansk, Poland; Tech Univ Catalonia, Spain.
    Kyhn, Line Anker
    Aarhus Univ, Denmark.
    Ljungqvist, Cinthia Tiberi
    Calluna AB, SE-58228 Linkoping, Sweden.
    Pawliczka, Iwona
    Univ Gdansk, Poland.
    Koza, Radomil
    Univ Gdansk, Poland.
    Arciszewski, Bartlomiej
    Univ Gdansk, Poland.
    Galatius, Anders
    Aarhus Univ, Denmark.
    Jabbusch, Martin
    German Oceanog Museum, Germany.
    Laaksonlaita, Jussi
    Turku Univ Appl Sci, Finland.
    Niemi, Jussi
    Turku Univ Appl Sci, Finland.
    Lyytinen, Sami
    Turku Univ Appl Sci, Finland.
    Gallus, Anja
    German Oceanog Museum, Germany.
    Benke, Harald
    German Oceanog Museum, Germany.
    Blankett, Penina
    Minist Environm, Finland.
    Skora, Krzysztof E.
    Univ Gdansk, Poland.
    Acevedo-Gutierrez, Alejandro
    Western Washington Univ, WA 98225 USA.
    Basin-scale distribution of harbour porpoises in the Baltic Sea provides basis for effective conservation actions2018In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 226, p. 42-53Article in journal (Refereed)
    Abstract [en]

    Knowledge on spatial and seasonal distribution of species is crucial when designing protected areas and implementing management actions. The Baltic Proper harbour porpoise (Phocoena phocoena) population is critically endangered, and its distribution is virtually unknown. Here, we used passive acoustic monitoring and species distribution models to describe the spatial and seasonal distribution of harbour porpoises in the Baltic Proper. Porpoise click detectors were deployed over a systematic grid of 297 stations in eight countries from April 2011 through July 2013. Generalized additive models were used to describe the monthly probability of detecting porpoise clicks as a function of spatially-referenced covariates and time. During the reproductive season, two main areas of high probability of porpoise detection were identified. One of those areas, situated on and around the offshore banks in the Baltic Proper, is clearly separated from the known distribution range of the Belt Sea population during breeding season, suggesting this is an important breeding ground for the Baltic Proper population. We commend the designation of this area as a marine protected area and recommend Baltic Sea countries to also protect areas in the southern Baltic Sea and the Hand Bight where additional important harbour porpoise habitats were identified. Further conservation measures should be carried out based on analyses of overlap between harbour porpoise distribution and potentially harmful anthropogenic activities. Our study shows that large-scale systematic monitoring using novel techniques can give important insights on the distribution of low-density populations, and that international cooperation is pivotal when studying transnationally migratory species.

  • 43.
    Carlsson, Evelina
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Danielsson, Elsa
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Det svenska skogsbrukets påverkan på den biologiska mångfalden: och ett förslag på hur lärare kan undervisa om detta i gymnasieskolan2016Student paper other, 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna litteraturstudie är att ge en bild av det svenska skogsbruket och dess påverkan på den biologiska mångfalden. Idag är det trakthyggesbruket som mest påverkar den biologiska mångfalden i Sverige och har lett till att många skogslevande arter idag är hotade och rödlistade. I denna studie har vi tittat på hur en produktionsskog skiljer sig från en naturskog när det gäller trädsammansättning, förekomst av död ved, fragmentering, skogskontinuitet och störning i form av brand. Vi har tittat på hur organismgrupperna svampar, lavar, mossor, kärlväxter, insekter, fåglar och däggdjur påverkas av skogsbruket. I denna studie ger vi även ett förslag på hur lärare, genom en exkursion, kan lära ut om biologisk mångfald i skolan. 

  • 44.
    Carlsson, Evelina
    et al.
    Linköping University, Department of Physics, Chemistry and Biology.
    Danielsson, Elsa
    Linköping University, Department of Physics, Chemistry and Biology.
    En jämförande studie av skogsstrukturer i olika skogstyper i Östergötland: och ett förslag på hur ett biologiprojekt som behandlar detta kan genomföras i gymnasiekursen Biologi 12017Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Syftet med denna studie är att undersöka vilka skillnader i skogsstrukturer det finns mellan olika skogstyper i Östergötland, samt att diskutera hur dessa skillnader kan påverka den biologiska mångfalden. De skogstyper vi besökt är; hyggen, skogar som är ungefär 40 år gamla, avverkningsanmälda skogar samt naturskogar som är bevarade som naturreservat. De skogsstrukturer vi undersökt är; trädarter, diameter på träd och död ved, nedbrytningsstadie på död ved, spår av brand samt antal håligheter i träd och död ved. Vår studie visade att alla skogstyper hade åtminstone någon av de strukturer som kännetecknar en skog med höga naturvärden och därmed högre biologisk mångfald.  Naturreservat var den skogstyp som hade flest skogsstrukturer som kännetecknar skogar med höga naturvärden. Detta tyder på att de hade en större biologisk mångfald gentemot de andra skogstyperna. Hyggen var den skogstyp som uppvisade minst skogsstrukturer som kännetecknar skogar med höga naturvärden vilket tyder på att den biologiska mångfalden var minst på hyggen. Syftet med studien är även att utforma en skoluppgift som liknar vår studie men är anpassad till biologiundervisningen i gymnasieskolan. För att göra detta har vi valt att återskapa vårt arbete som ett biologiprojekt för gymnasiekursen Biologi 1. Detta biologiprojekt innefattar en exkursion med förberedelser och efterarbete. 

  • 45.
    Carlsson, Rebecka
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Skogsväxters utbredning i relation till pH, latitud och trädsammansättning: Exkursion för ekologiundervisning2016Independent thesis Advanced level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This study investigated the impact of three edaphic factors on the distribution of forest plants in Sweden. Based on 2657 plots with 22 common species, Canonical Correspondence Analysis (CCA) and Generalized-linear-model (GLM) were performed with pH measurements in the top layer of the soil, latitude and deciduous tree proportion as explanatory variables. Variation of the species occurrence could to a substantial degree be explained by pH, latitude and proportion of timber volume of deciduous tree species. Furthermore, the majority of species were affected by the studied environmental variables. Therefore, these factors have an important role in the ecological interactions in the forest. All species also showed broad pH-niches with many occurrences spread out within the species entire pH-range. Finally, the study relates to educational science through designing a meaningful excursion for secondary school when teaching ecology.

  • 46.
    Carlsson, Staffan
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Boxing for biodiversity: a long-term follow up of an artificial dead wood environment2015Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Today many saproxylic species are threatened because of habitat decline in Europe. Hollow trees represent a great part of the habitats that saproxylic species use. Since hollows takes a long time to develop, management actions are needed to prevent the extinction of saproxylic species. The aim of this study was to investigate the succession of saproxylic beetle species in artificial habitats in the form of wooden boxes. Wooden boxes were filled with a potential substrate and placed at different distances (0-1800 m) from oak hollow hot spots. In addition to the start mixture, four different additional substrates were added. In total, 4510 specimens of 114 saproxylic beetle species were sampled in 43 boxes over ten years. The specimens of tree-hollow species, wood rot species and nest species increased with 38% from the fourth to the final year but species richness decline from 47 to 29, respectively. A dead hen had a tendency for attracting more species but the small effect of different added substrates diminished over the years and had no significant effect on species richness after ten years. There was a higher similarity in species richness after ten years between the boxes and real hollow oaks. In conclusion, the artificial habitat developed into a more hollow like environment, with fewer but more abundant wood mould specialists, during ten years. This study clearly shows that the wooden boxes are used as habitats for saproxylic species as the boxes seems to develop into a more hollow-like habitat with time.

  • 47.
    Carlsson, Staffan
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, The Institute of Technology.
    Skillnader i mulmvolymer mellan fem trädslag i Östergötlands eklandskap2013Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Old hollow trees of oak contain a large amount of wood mould. Unfortunately, these trees have in the last century been greatly reduced in numbers. It has resulted in that species that depend on these habitats, saproxylic species, have become at risk to decrease in numbers or die out regionally. Previous studies have shown that the volume of wood mould is an important factor for occurrence and population size of saproxylic organisms. The aim of the present study was to examine how the volume of wood mould varies among ash (Fraxinus excelsior), lime (Tilia sp.), maple (Acer platanoides), aspen (Populus tremula) and oak (Quercus robur). The measurements were wood mould depth, internal cavity diameter, internal cavity height, circumference, and if white or brown rot was the dominating mould fungus. In total 23 ashes, 20 limes, 24 maples, 24 aspens and 21 oaks in the vicinity of Motala (Östergötland) were measured. The results show that there were significant differences between tree species concerning the volumes of wood mould. The oak accommodated larger volumes than the other species. The ash, however, had a larger volume than oak at the same circumference. The study shows ash could be a complement to the oak in conservation plans. Since the ash generally holds a larger volume then the oak at the same circumference, this implies the possibility that the ash can be suitable for saproxylic organisms at an earlier stage. In the isolated fragments of the landscape the possibility for survival may then increase for species that are dependent of these habitats.

  • 48.
    Carlsson, Staffan
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Bergman, Karl-Olof
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Jansson, Nicklas
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Ranius, Thomas
    Department of Ecology, Swedish University of Agricultural Sciences, Box 7044, 750 07 Uppsala, Sweden.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Ecology. Linköping University, Faculty of Science & Engineering.
    Boxing for biodiversity: evaluation of an artificiallycreated decaying wood habitat2016In: Biodiversity and Conservation, ISSN 0960-3115, E-ISSN 1572-9710, Vol. 25, no 2, p. 393-405Article in journal (Refereed)
    Abstract [en]

    Many saproxylic species are threatened in Europe because of habitat decline.Hollow trees represent an important habitat for saproxylic species. Artificial habitats mayneed to be created to maintain or increase the amount of habitat due to natural habitat decline.This study investigated the extent to which saproxylic beetles use artificial habitats in woodenboxes. The boxes were placed at various distances (0–1800 m) from known biodiversityhotspots with hollow oaks and studied over 10 years. Boxes were mainly filled with oak sawdust, oak leaves, hay and lucerne flour. In total, 2170 specimens of 91 saproxylic beetlespecies were sampled in 43 boxes. The abundance of species associated with tree hollows,wood rot and animal nests increased from the fourth to the final year, but species richnessdeclined for all groups. This study shows that wooden boxes can function as saproxylicspecies habitats. The artificial habitats developed into a more hollow-like environment duringthe decade long experiment with fewer but more abundant tree hollow specialists.

  • 49.
    Choudhury, Md. Maidul Islam
    Linköping University, Department of Physics, Chemistry and Biology, Ecology. Linköping University, The Institute of Technology.
    Does an evolutionary change in the water sowbug Asellus aquaticus L. alter its functional role?2011Independent thesis Advanced level (degree of Master (Two Years)), 60 credits / 90 HE creditsStudent thesis
    Abstract [en]

    The ecology behind evolutionary diversification is a well studied area of research, whereas the effects of evolution on ecosystems get little attention. In line with ecological theory, evolutionary diversification of a species could influence different ecosystem aspects such as food web composition, energy flow, nutrient cycling etc. The main objective of this study was to investigate whether two diverging ecotypes (reed and chara) of Asellus aquaticus differ regarding their role in two aquatic ecosystem processes: decomposition of terrestrial leaves and grazing of periphyton. Their role in ecosystem process as well as treatment effects on fitness, measured as growth and survival, were investigated in a laboratory experiment with various levels of intra-specific competition and inter-specific interactions with the amphipod Gammarus pulex. The isopods were collected from two Swedish lakes: Lake Tåkern and Lake Fardume. These two lakes represent different history of ecotype divergence. The experimental design consisted of 2-L aquaria, each providing elm leaves (Ulmus glabra), oak leaves (Quercus roburleaves) and periphyton as food sources. Ten treatments with five replicates were applied for each lake and the experiment lasted for four weeks. The study showed that there was no significant difference between chara and reed ecotype in their functional role. However, the rate of ecosystem processes per individual decreased in competitive interactions. In high density, decomposition per dry weight consumer was low and total algae biomass was high at the end of four weeks due to intra-specific competition. Moreover, ecosystem processes were lowest in inter-specific competition between Gammarus pulex and each ecotype. Present study also shows that ecotypes from the different lakes, having different history, had different responses to mortality and growth. 

  • 50.
    Cirtwill, Alyssa
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering.
    Dalla Riva, Giulio V.
    Department of Statistics, University of British Columbia, Vancouver, Canada; School of Mathematics and Statistics, University of Canterbury, Christchurch, New Zealand.
    Gaiarsa, Marilia P.
    Departamento de Ecologia Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil; Department of Entomology, University of California, Riverside, California, USA.
    Bimler, Malyon D.
    School of Biological Sciences, University of Queensland, Brisbane, Australia.
    Cagua, E. Fernando
    Centre for Integrative Ecology, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand.
    Coux, Camille
    UMR 1065 Santé et Agroécologie du Vignoble, INRA Bordeaux-Aquitaine, France; Centre d’Etudes Biologiques de Chizé UMR 7372, CNRS, Université de La Rochelle, France.
    Dehling, D. Matthias
    Centre for Integrative Ecology, School of Biological Sciences, University of Canterbury, Christchurch, New Zealand.
    A review of species role concepts in food webs2018In: Food Webs, E-ISSN 2352-2496, Vol. 16, article id e00093Article in journal (Refereed)
    Abstract [en]

    Many different concepts have been used to describe species' roles in food webs (i.e., the ways in which species participate in their communities as consumers and resources). As each concept focuses on a different aspect of food-web structure, it can be difficult to relate these concepts to each other and to other aspects of ecology. Here we use the Eltonian niche as an overarching framework, within which we summarize several commonly-used role concepts (degree, trophic level, motif roles, and centrality). We focus mainly on the topological versions of these concepts but, where dynamical versions of a role concept exist, we acknowledge these as well. Our aim is to highlight areas of overlap and ambiguity between different role concepts and to describe how these roles can be used to group species according to different strategies (i.e., equivalence and functional roles). The existence of “gray areas” between role concepts make it essential for authors to carefully consider both which role concept(s) are most appropriate for the analyses they wish to conduct and what aspect of species' niches (if any) they wish to address. The ecological meaning of differences between species' roles can change dramatically depending on which role concept(s) are used.

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