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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.

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  • 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.
    Alexis, Jimmy
    Linköping University, Department of Physics, Chemistry and Biology.
    Biodiversitet i boreala skogar Hur påverkas den av olika skogsbruksmetoder?2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The modern clear-cutting practice in forestry has had a major impact on biodiversity in the forest. Many organisms that depend on structures linked to older forests are declining in number and are now endangered. Today, it is debated whether alternative forestry methods are better at preserving the structure of the forest and the biological diversity. In this literature study, studies were compiled that have compared how different forestry methods have affected biodiversity. The results showed that continuous cover forestry to a greater extent retains the structures of an older forest and had the least impact on the species associated with older, continuous forest. For some of the most sensitive species, however, all felling has a negative impact. Clear-cutting is what changes the species composition the most, and species that depend on continuity forests are often replaced by generalists and species that prefer open habitats. The studies show that greater nature conservation considerations in clear-cutting can sometimes reduce the impact on species composition. All kinds of forestry methods reduce the amount and degrade the quality of dead wood in the forest. The studies show that several alternative forestry methods have a greater potential to preserve or create dead wood compared to clear-cutting. Results also show that there are several suitable methods that can be used in forestry. In order to achieve and maintain a high level of biodiversity at landscape level, a mixture of different forestry methods seems optimal.

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  • 6.
    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.

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  • 7.
    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.

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    Examensarbete Biologi Felicia Alriksson
  • 8.
    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.

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    Dynamics of phosphorus transport and retention in a wetland receiving drainage water from agricultural clay soils
  • 9.
    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.

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  • 10.
    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.

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  • 11.
    Andersson, Petter
    et al.
    Unaffiliated, Nacka, Sweden.
    Koffman, Anna
    Unaffiliated, Nacka, Sweden.
    Sjödin, N. Erik
    Swedish Environmental Protection Agency, Stockholm, Sweden.
    Johansson, Victor
    Swedish University of Agricultural Sciences, Uppsala, Sweden.
    Roads may act as barriers to flying insects: Species composition of bees and wasps differs on two sides of a large highway2017In: Nature Conservation, ISSN 1314-6947, E-ISSN 1314-3301, Vol. 18, p. 47-59Article in journal (Refereed)
    Abstract [en]

    Roads may act as barriers to animal movements, but direct barrier effects on insects have rarely been studied. In this study we collected data on bees and wasps along two sides of a large road in Sweden using yellow pan traps. We then analyzed if the species composition differed between the two sides of the road; first for the whole community, and then only for the smallest species (which typically are poorer dispersers). As a complement, we analyzed if different vegetation variables differed between the two sides of the road, as this may also affect differences in species composition. Finally, we analyzed if species richness and abundance in general differed between the two sides and how these two response variables were explained by the vegetation variables. There was a significant difference in species composition between the eastern and the western side of the road when analyzing the whole community, and this relationship became even stronger when the largest species were excluded. The vegetation variables did not strongly differ between the two sides, and there was no difference in species richness and abundance of bees and wasps either. Abundance was, however, explained by the number of flowering plants in the surroundings of the trap. Even though using a rather limited data set, our results indicate that large roads may act as barriers on the movement of bees and wasps, especially for small species with poor dispersal ability. On the other hand, road verges may be important habitat for many species, which leads to a potential conflict that is important to consider in the planning of green infrastructure.

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  • 12.
    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.

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    Beror förekomsten av sjöfågel i anlagda våtmarker på våtmarkens ålder och area?
  • 13.
    Aoyama, Lina
    et al.
    Univ Oregon, OR 97403 USA; Univ Oregon, OR 97403 USA.
    Shoemaker, Lauren G.
    Univ Wyoming, WY 82071 USA.
    Gilbert, Benjamin
    Univ Toronto, Canada.
    Collinge, Sharon K.
    Univ Colorado, CO 80309 USA.
    Faist, Akasha M.
    New Mexico State Univ, NM 88003 USA.
    Shackelford, Nancy
    Univ Victoria, Canada; Univ Colorado Boulder, CO USA.
    Temperton, Vicky M.
    Leuphana Univ, Germany.
    Barabas, György
    Linköping University, Department of Physics, Chemistry and Biology, Ecological and Environmental Modeling. Linköping University, Faculty of Science & Engineering. Univ Calif Riverside, CA USA.
    Larios, Loralee
    Univ Calif Riverside, CA USA.
    Ladouceur, Emma
    German Ctr Integrat Biodivers Res iDiv Leipzig Ha, Germany; UFZ Helmholtz Ctr Environm Res, Germany.
    Godoy, Oscar
    Inst Univ Invest Marina INMAR, Spain.
    Bowler, Catherine
    Univ Queensland, Australia.
    Hallett, Lauren M.
    Univ Oregon, OR 97403 USA; Univ Oregon, OR 97403 USA.
    Application of modern coexistence theory to rare plant restoration provides early indication of restoration trajectories2022In: Ecological Applications, ISSN 1051-0761, E-ISSN 1939-5582, Vol. 32, no 7, article id e2649Article in journal (Refereed)
    Abstract [en]

    Restoration ecology commonly seeks to re-establish species of interest in degraded habitats. Despite a rich understanding of how succession influences re-establishment, there are several outstanding questions that remain unaddressed: are short-term abundances sufficient to determine long-term re-establishment success, and what factors contribute to unpredictable restorations outcomes? In other words, when restoration fails, is it because the restored habitat is substandard, because of strong competition with invasive species, or alternatively due to changing environmental conditions that would equally impact established populations? Here, we re-purpose tools developed from modern coexistence theory to address these questions, and apply them to an effort to restore the endangered Contra Costa goldfields (Lasthenia conjugens) in constructed ("restored") California vernal pools. Using 16 years of data, we construct a population model of L. conjugens, a species of conservation concern due primarily to habitat loss and invasion of exotic grasses. We show that initial, short-term appearances of restoration success from population abundances is misleading, as year-to-year fluctuations cause long-term population growth rates to fall below zero. The failure of constructed pools is driven by lower maximum growth rates compared with reference ("natural") pools, coupled with a stronger negative sensitivity to annual fluctuations in abiotic conditions that yield decreased maximum growth rates. Nonetheless, our modeling shows that fluctuations in competition (mainly with exotic grasses) benefit L. conjugens through periods of competitive release, especially in constructed pools of intermediate pool depth. We therefore show how reductions in invasives and seed addition in pools of particular depths could change the outcome of restoration for L. conjugens. By applying a largely theoretical framework to the urgent goal of ecological restoration, our study provides a blueprint for predicting restoration success, and identifies future actions to reverse species loss.

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  • 14.
    Arnoldi, Jean-Francois
    et al.
    CNRS, France.
    Barbier, Matthieu
    CIRAD, France.
    Kelly, Ruth
    Agrifood & Biosci Inst, North Ireland.
    Barabas, György
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering. ELTE MTA Theoret Biol & Evolutionary Ecol Res Grp, Hungary.
    Jackson, Andrew L.
    Univ Dublin, Ireland.
    Invasions of ecological communities: Hints of impacts in the invaders growth rate2022In: Methods in Ecology and Evolution, E-ISSN 2041-210X, Vol. 13, no 1, p. 167-182Article in journal (Refereed)
    Abstract [en]

    1. Theory in ecology and evolution often relies on the analysis of invasion processes, and general approaches exist to understand the early stages of an invasion. However, predicting the long-term transformations of communities following an invasion remains a challenging endeavour. 2. We propose a general analytical method that uses both resident community and invader dynamical features to predict whether an invasion causes large long-term impacts on the invaded community. 3. This approach reveals a direction in which classic invasion analysis, based on initial invasion growth rate, can be extended. Indeed, we explain how the density dependence of invasion growth, if properly defined, synthetically encodes the long-term biotic transformations caused by an invasion, and therefore predicts its ultimate outcome. This approach further clarifies how the density dependence of the invasion growth rate is as much a property of the invading population as it is one of the invaded community. 4. Our theory applies to any stable community model, and directs us towards new questions that may enrich the toolset of invasion analysis, and suggests that indirect interactions and dynamical stability are key determinants of invasion outcomes.

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  • 15.
    Arslangundogdu, Zeynel
    et al.
    Istanbul Univ Cerrahpasa, Turkiye.
    Hizal, Erdem
    Istanbul Univ Cerrahpasa, Turkiye.
    Bergner, Adam
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Jansson, Niklas
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    The Importance of Urban Green Spaces for Resident and Migrant Birds - A Case Study from Tepeören Cemetery in Istanbul-Türkiye2023In: KASTAMONU UNIVERSITY JOURNAL OF FORESTRY FACULTY, ISSN 1303-2399, Vol. 23, no 2, p. 131-143Article in journal (Refereed)
    Abstract [en]

    Aim of study: This study was carried out to determine the effects and importance of urban cemeteries on bird species diversity. Area of study: The Tepeoren cemetery is one of the oldest and most historically important cemeteries in the Istanbul region. Material and methods: Field studies of birds were carried out between April-September 2018/2019. During the study period of 12 months, the cemetery was visited twice a month. The species list of the area was created by registering all feeding, lodging, roosting and nesting birds observed in the area. Main results: It was determined that 36 bird species occured in the cemetery, out of which ten species were identified as breeding in the area. The main bird species that used the cemetery as breeding ground, was Corvus monedula (Western jackdaw) that utilizes the cavities of old oaks for nesting. The average number of eggs per nest was found to be 4.3 based on the examination of 49 active nests in 2018-2019. The number of fledged birds per nest was determined as 1.1. Higlights: In the current study, the importance of the city cemeteries in terms of bird diversity has been revealed. The presence of plant species that provide suitable nesting conditions for the reproduction of birds in these cemeteries supports the survival of the birds in the city.

  • 16.
    Auffret, Alistair G.
    et al.
    Swedish Univ Agr Sci, Sweden.
    Vangansbeke, Pieter
    Univ Ghent, Belgium.
    De Frenne, Pieter
    Univ Ghent, Belgium.
    Auestad, Inger
    Western Norway Univ Appl Sci, Norway.
    Basto, Sofia
    Pontificia Univ Javeriana, Colombia.
    Grandin, Ulf
    Swedish Univ Agr Sci, Sweden.
    Jacquemyn, Hans
    Katholieke Univ Leuven, Belgium.
    Jakobsson, Anna
    Univ West, Sweden.
    Kalamees, Rein
    Univ Tartu, Estonia; Tallinn Bot Garden, Estonia.
    Koch, Marcus A.
    Heidelberg Univ, Germany.
    Marrs, Rob
    Univ Liverpool, England.
    Marteinsdottir, Bryndis
    Soil Conservat Serv Iceland, Iceland.
    Wagner, Markus
    UK Ctr Ecol & Hydrol, England.
    Bekker, Renee M.
    Univ Groningen, Netherlands.
    Bruun, Hans Henrik
    Univ Copenhagen, Denmark.
    Decocq, Guillaume
    Jules Verne Univ Picardie, France.
    Hermy, Martin
    Katholieke Univ Leuven, Belgium.
    Jankowska-Blaszczuk, Malgorzata
    Jan Kochanowski Univ Humanities & Sci, Poland.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Maren, Inger E.
    Univ Bergen, Norway.
    Pakeman, Robin J.
    James Hutton Inst, Scotland.
    Phoenix, Gareth K.
    Univ Sheffield, England.
    Thompson, Ken
    Univ Sheffield, England.
    Van Calster, Hans
    Res Inst Nat & Forest, Belgium.
    Vandvik, Vigdis
    Plue, Jan
    Swedish Univ Agr Sci, Sweden.
    More warm-adapted species in soil seed banks than in herb layer plant communities across Europe2023In: Journal of Ecology, ISSN 0022-0477, E-ISSN 1365-2745Article in journal (Refereed)
    Abstract [en]

    Responses to climate change have often been found to lag behind the rate of warming that has occurred. In addition to dispersal limitation potentially restricting spread at leading range margins, the persistence of species in new and unsuitable conditions is thought to be responsible for apparent time-lags. Soil seed banks can allow plant communities to temporarily buffer unsuitable environmental conditions, but their potential to slow responses to long-term climate change is largely unknown. As local forest cover can also buffer the effects of a warming climate, it is important to understand how seed banks might interact with land cover to mediate community responses to climate change. We first related species-level seed bank persistence and distribution-derived climatic niches for 840 plant species. We then used a database of plant community data from grasslands, forests and intermediate successional habitats from across Europe to investigate relationships between seed banks and their corresponding herb layers in 2763 plots in the context of climate and land cover. We found that species from warmer climates and with broader distributions are more likely to have a higher seed bank persistence, resulting in seed banks that are composed of species with warmer and broader climatic distributions than their corresponding herb layers. This was consistent across our climatic extent, with larger differences (seed banks from even warmer climates relative to vegetation) found in grasslands. Synthesis. Seed banks have been shown to buffer plant communities through periods of environmental variability, and in a period of climate change might be expected to contain species reflecting past, cooler conditions. Here, we show that persistent seed banks often contain species with relatively warm climatic niches and those with wide climatic ranges. Although these patterns may not be primarily driven by species climatic adaptations, the prominence of such species in seed banks might still facilitate climate-driven community shifts. Additionally, seed banks may be related to ongoing trends regarding the spread of widespread generalist species into natural habitats, while cool-associated species may be at risk from both short- and long-term climatic variability and change.

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  • 17.
    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.

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  • 18.
    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.

  • 19.
    Barabas, György
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering. Eotvos Lorand Univ, Hungary.
    Biodiversity and community structure2021In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 118, no 11, article id e2101176118Article in journal (Other academic)
    Abstract [en]

    n/a

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  • 20.
    Barabas, György
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering. MTA ELTE Theoret Biol & Evolutionary Ecol Res Grp, Hungary.
    DAndrea, Rafael
    Univ Illinois, IL 61801 USA.
    Chessons coexistence theory: reply2020In: Ecology, ISSN 0012-9658, E-ISSN 1939-9170, Vol. 101, no 11, article id e03140Article in journal (Other academic)
    Abstract [en]

    n/a

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  • 21.
    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.

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  • 22.
    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.

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  • 23.
    Barabas, György
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Theoretical Biology. Linköping University, Faculty of Science & Engineering. ELTE MTA Theoret Biol & Evolutionary Ecol Res Grp, Hungary.
    Parent, Christine
    Univ Idaho, ID 83844 USA.
    Kraemer, Andrew
    Creighton Univ, NE 68178 USA.
    Van de Perre, Frederik
    Univ Antwerp, Belgium.
    De Laender, Frederik
    Univ Namur, Belgium.
    The evolution of trait variance creates a tension between species diversity and functional diversity2022In: Nature Communications, E-ISSN 2041-1723, Vol. 13, no 1, article id 2521Article in journal (Refereed)
    Abstract [en]

    It seems intuitively obvious that species diversity promotes functional diversity: communities with more plant species imply more varied plant leaf chemistry, more species of crops provide more kinds of food, etc. Recent literature has nuanced this view, showing how the relationship between the two can be modulated along latitudinal or environmental gradients. Here we show that even without such effects, the evolution of functional trait variance can erase or even reverse the expected positive relationship between species- and functional diversity. We present theory showing that trait-based eco-evolutionary processes force species to evolve narrower trait breadths in more tightly packed, species-rich communities, in their effort to avoid competition with neighboring species. This effect is so strong that it leads to an overall reduction in trait space coverage whenever a new species establishes. Empirical data from land snail communities on the Galapagos Islands are consistent with this claim. The finding that the relationship between species- and functional diversity can be negative implies that trait data from species-poor communities may misjudge functional diversity in species-rich ones, and vice versa. The positive relationship between species diversity and functional diversity has been shown to vary. Here, the authors use theoretical models and data from Galapagos land snail communities to show how eco-evolutionary processes can force species to evolve narrower trait breadths in more species-rich communities to avoid competition, creating a negative relationship.

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  • 24.
    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.

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  • 25.
    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.

  • 26.
    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.

  • 27.
    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.

  • 28.
    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.

  • 29.
    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.

  • 30.
    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.

  • 31.
    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.

  • 32.
    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.

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  • 33.
    Bergman, Karl-Olof
    Linköping University, Department of Physics, Measurement Technology, Biology and Chemistry. Linköping University, The Institute of Technology.
    Ecology and conservation of the butterfly Lopinga achine2000Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The ecology of the red-listed butterfly Lopinga achine was studied in partly open woodlands in the province of Östergotland, Sweden. Detailed autoecological research is essential for successful conservation of a species, and the present investigation focused on the initial aspects of such work, namely, choice of host plant, habitat selection, and dispersal ability. The effects of patch area, isolation, and successional stages of studied sites were also examined.

    The results indicate that L. achine depends on a single host plant, Carex montana. The females preferred to oviposit near this sedge, and most of the larvae (> 80%) were found on C. montana in the field. Egg-laying females and larvae were restricted to C. montana growing in a narrow zone along the edges of glades. This restriction to forest edges is probably the cause for the dependence of L. achine on a restricted stage of canopy cover. More specifically, no L. achine occurred at sites with less than 60% canopy cover, and population densities decreased sharply with more than 90% cover. Eighty-six percent of the studied sites that were occupied are unmanaged, thus the most important aspect of long-term conservation of L. achine is probably the deterministic changes of its woodland habitat. If the sites remain unmanaged, the system of populations will most likely collapse within 20-40 years. Populations of both L. achine and C. montana increased in size at experimentally managed sites where new glades were created. However, an important prerequisite of successful restoration appears to be the presence of C. montana along the edges of new glades from the start, because the rate of C. montana colonisation was slow.

    Most of the populations (50 of 79) were small (< 500 adults; none larger than 4,500) and seemed to show synchronous interannual fluctuation. The probability that a patch would be occupied increased with increasing patch area and decreasing distance to the nearest occupied patch. This was presumably due to different probabilities of extinctions, colonisations, and survival of the inhabiting populations. All but two of the sites with ≥ 3 individuals were within 740 m of the nearest neighbour. Patch size is also a key factor for occurrence: compared to larger patches, small patches are more dependent on neighbour populations.

    The majority of the movements were small and within sites, although in many cases the distance to other sites was less than 100 m. Only 56 individuals (4.0% of those recaptured) moved between sites. It seems that habitat patches of L. achine should be less than 700 m from each other to ensure inter-population contact. Fifteen to 20 wellconnected populations have been stated as a lower limit for a viable metapopulation.Based on these criteria, there are two groups of viable populations in the studied area,and these two groups will be given priority in future conservation work.

    List of papers
    1. Oviposition, host plant choice and survival of a grass feeding butterfly, the Woodland Brown (Lopinga achine)
    Open this publication in new window or tab >>Oviposition, host plant choice and survival of a grass feeding butterfly, the Woodland Brown (Lopinga achine)
    2000 (English)In: Journal of research on the Lepidoptera, ISSN 0022-4324, Vol. 35Article in journal (Refereed) Published
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-42457 (URN)64702 (Local ID)64702 (Archive number)64702 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2022-06-17
    2. Habitat utilization by Lopinga achine (Nymphalidae: Satyrinae) larvage and ovipositing females
    Open this publication in new window or tab >>Habitat utilization by Lopinga achine (Nymphalidae: Satyrinae) larvage and ovipositing females
    1999 (English)In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 88, p. 69-74Article in journal (Refereed) Published
    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-42455 (URN)64699 (Local ID)64699 (Archive number)64699 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2022-06-17
    3. Population structure and movements of a threatened butterfly (Lopinga achine) in a fragmented landscape in Sweden
    Open this publication in new window or tab >>Population structure and movements of a threatened butterfly (Lopinga achine) in a fragmented landscape in Sweden
    2002 (English)In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 108, no 3, p. 361-369Article in journal (Refereed) Published
    Abstract [en]

    The red-listed butterfly Lopinga achine was studied by mark-recapture methods in southern Sweden for three seasons. We examined movement within and between populations and egg production in relation to age. The majority of the movements were small with mean movements between recaptures of 45-54 m for males and 94-116 m for females. There were few movements between sites, 20 of 996 recaptured males moved and 36 of 391 recaptured females, even though the distance to other sites was in many cases < 100 m. The distance moved and the number of females moving between sites increased with increasing age. On average, a female that moves does so after laying two-thirds of its eggs in its natal site. It is therefore important to take account of the proportion of reproductive effort involved in dispersal when estimating colonisation ability. The males did not move more with increasing age. Female behaviour can be seen as a "spread-the-risk" strategy, an adaptation to the successional habitat of L. achine, whose natal site sooner or later will deteriorate. Butterflies like L. achine living in successional habitats may exhibit mobility that is intermediate between butterflies living in ephemeral habitats (very mobile) and in long-lived habitats (sedentary). ⌐ 2002 Elsevier Science Ltd. All rights reserved.

    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-42460 (URN)10.1016/S0006-3207(02)00104-0 (DOI)64706 (Local ID)64706 (Archive number)64706 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2022-06-17
    4. Distribution of occupied and vacant sites and migration of Lopinga achine (Nymphalidae: Satyrinae) in a fragmented landscape
    Open this publication in new window or tab >>Distribution of occupied and vacant sites and migration of Lopinga achine (Nymphalidae: Satyrinae) in a fragmented landscape
    2001 (English)In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 102, no 2, p. 183-190Article in journal (Refereed) Published
    Abstract [en]

    The distribution of occupied and vacant sites and migration of the threatened butterfly Lopinga achine were studied in the province of ╓sterg÷tland, Sweden. The probability of occupation increased with increasing patch area and decreasing distance to the nearest occupied patch, presumably due to different probabilities of colonisation and survival of the populations inhabiting the patches. Probability of female emigration from and immigration to a patch increased with decreasing area. Middle-sized patches produced the largest number of female migrants, although the highest fraction was noted for the smallest patches, and the greatest number of females was marked in the largest patch. The fraction of resident females, but not males, increased with increasing area. The observed occupancy and migration pattern have important conservation implications: all but two populations comprising three or more individuals were within 740 m of the nearest neighbour, indicating the need for networks of suitable, closely situated patches. ⌐ 2001 Elsevier Science Ltd. All rights reserved.

    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-42459 (URN)10.1016/S0006-3207(01)00081-7 (DOI)64705 (Local ID)64705 (Archive number)64705 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2022-06-17
    5. Population dynamics and the importance of habitat management for conservation of the butterfly Lopinga achine
    Open this publication in new window or tab >>Population dynamics and the importance of habitat management for conservation of the butterfly Lopinga achine
    2001 (English)Article in journal (Refereed) Published
    Abstract [en]

    1. Like many butterflies, the woodland brown Lopinga achine has disappeared from many locations in western Europe due to habitat loss. The population dynamics and the effects of tree and bush cover on population size were studied experimentally south of Link÷ping, Sweden. 2. Most populations in the study area were small (< 500 individuals) and fluctuated synchronously between years. Long-term population dynamics and occurrence were closely correlated with tree and bush cover. Populations occurred only at sites with = 60% canopy cover, but population density decreased sharply where cover exceeded 90%. Survival from egg to adult was highest at the edges of glades (2.3 adults per female) and lowest in the deepest shade (0.7 adults) or open sun (0.6 adults). The annual rate of canopy closure at unmanaged sites decreased linearly with tree and bush cover, approximately 1% closure at 60% cover and 0.3% at 85% cover, making it possible to predict the impact of habitat changes for L. achine. 3. In 1992-95, vegetation was cleared experimentally to create new glade edges at six unmanaged sites where the risk of extinction was high because few glades remained. On average, population size at five of the managed sites increased by > 90%. The population at the sixth site, managed in 1995, decreased by 30%. 4. Cover of the host-plant Carex montana increased significantly at edges of new glades and decreased in closed unaffected woods. Successful restoration probably requires the presence of C. montana along edges of new glades from the onset of management because this plant was slow to colonize plots where it was initially absent. 5. Currently, 86% of the sites in southern Sweden occupied by L. achine are unmanaged. If this situation continues, the metapopulation in this study will probably collapse within 20-40 years. Recovery programmes for L. achine should emphasize metapopulation dynamics, host-plant cover and vegetation dynamics over time. As with many butterflies, successful conservation requires a blend of detailed autoecology and active site management to produce the required successional conditions.

    National Category
    Natural Sciences
    Identifiers
    urn:nbn:se:liu:diva-42458 (URN)10.1046/j.0021-8901.2001.00672.x (DOI)64703 (Local ID)64703 (Archive number)64703 (OAI)
    Available from: 2009-10-10 Created: 2009-10-10 Last updated: 2022-06-17
  • 34.
    Bergman, Karl-Olof
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Burman, Joseph
    Swedish Univ Agr Sci, Sweden; Canterbury Christ Church Univ, England.
    Jonason, Dennis
    Linköping University, Department of Physics, Chemistry and Biology. Linköping University, Faculty of Science & Engineering.
    Larsson, Mattias C.
    Swedish Univ Agr Sci, Sweden.
    Ryrholm, Nils
    Univ Gavle, Sweden.
    Westerberg, Lars
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Milberg, Per
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Clear-cuts are temporary habitats, not matrix, for endangered grassland burnet moths (Zygaena spp.)2020In: Journal of Insect Conservation, ISSN 1366-638X, E-ISSN 1572-9753, Vol. 24, no 2, p. 269-277Article in journal (Refereed)
    Abstract [en]

    Burnet moths (Zygaena spp.) are day-flying Lepidoptera considered indicative of species-rich grasslands. In the present study, our aim was to clarify whether clear-cuts are habitat, supporting habitat or matrix for three species of Zygaena. We did so by sampling these species with sex pheromones on 48 clear-cuts, varying in amount of host and nectar plants, in southern Sweden. To compare the efficiency of such sampling, we also conducted transect walks on these clearcuts. Overall, host-plants on clear-cuts best explained the abundance of Zygaena spp. recorded, better than nectar-plants or connectivity with nearby grasslands. These results indicate that clear-cuts with an abundance of host plants are used as a fully functional habitat, and not a supporting habitat in the sense of only providing nectar. There is no support in these results for considering clear-cuts as an inert matrix. With about half the work-effort, pheromone traps recorded 100 times more Zygaena spp. as transect walks. The poor correspondence between observations during transects walks and pheromone trap catches suggest Zygaena spp. being difficult to monitor by transect walks. In contrast to grasslands, clear-cuts are short-term in nature requiring repeated recolonization, indicating the importance of permanent grasslands. However, clear-cuts are important temporary insect habitats due to their great acreage, and suitable management can increase the time they remain a habitat.

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  • 35.
    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.

  • 36.
    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.

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  • 37.
    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.

  • 38. Order onlineBuy this publication >>
    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
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  • 39.
    Bergstedt, Johan
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Axelsson, Anna-Lena
    SLU Umeå.
    Karlsson, Jesper
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Lönander, Johanna
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Törnqvist, Lina
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    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.

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  • 40.
    Bertoluci, Jaime
    et al.
    Univ Sao Paulo, Brazil.
    Sawakuchi, Henrique
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences.
    Ortiz, Carolina
    Univ Sao Paulo, Brazil.
    Brassaloti, Ricardo Augusto
    Univ Sao Paulo, Brazil.
    Ribeiro-Junior, Jose Wagner
    Univ Estadual Paulista, Brazil.
    Famelli, Shirley
    Univ Sao Paulo, Brazil.
    Anuran fauna of the Parque Estadual Carlos Botelho - Nficleo Sete Barras, southeastern Brazil: species composition, use of breeding sites, and seasonal patterns of breeding activity2021In: Biota neopropica, ISSN 1678-6424, E-ISSN 1676-0603, Vol. 21, no 1, article id e20201082Article in journal (Refereed)
    Abstract [en]

    The goal of this work was to study the species composition, the use of breeding sites, and the seasonal patterns of breeding activity of the anuran fauna from Parque Estadual Carlos Botelho - Nucleo Sete Barras, state of Sao Paulo, southeastern Brazil. Fieldwork was carried out from September 2005 to October 2007 through two main methods: active visual search inside a 10 ha- permanent plot and aural and visual search in seven previously selected aquatic breeding habitats. Species richness was related to the sampling effort by means of species accumulation curve and through non-parametric estimators. Thirty-three species distributed in 12 families were recorded, from which 69% are endemic to the Atlantic Forest. Trachycephalus mesophaeus represents a new record for the park. Cycloramphus lutzorum is included as Data Deficient in the IUCN list. The species accumulation curve did not stabilize, showing some tendency to rise. The use of breeding sites by 20 species was compared using cluster analysis, which revealed two major groups: the first with five species (two habitat generalists and three stream specialists) and the second composed by the other species (with different reproductive modes associated with flooded environments). The breeding period of most species was associated to the rainy season (October to February), and only Scinax hayii showed continuous breeding activity during the entire period of study.

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  • 41.
    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)
  • 42.
    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.

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  • 43.
    Björklund Aksoy, Simon
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Do potentially seal-safe pingers deter harbour porpoises (Phocoena phocoena) in the vicinity of gillnets and thereby reduce bycatch?2020Independent thesis Advanced level (degree of Master (Two Years)), 40 credits / 60 HE creditsStudent thesis
    Abstract [en]

    Incidental bycatch in gillnets is a substantial threat to small cetaceans. Using Acoustic Deterrent Devices, “pingers”, have successfully reduced bycatch of harbour porpoises in gillnets. However, seals can use pingers as “dinner-bells” to easier find gillnets in order to raid and destroy them, further aggravating the existing conflicts between seals and coastal fisheries. Therefore, in the present study, the efficiency of two alleged “seal-safe” pingers, an experimental Banana pinger “SSB” and a Future Oceans F70 pinger “FO”, in deterring harbour porpoises from the vicinity of gillnets and thereby reducing bycatch in commercial gillnet fisheries, was tested. This was done by deploying click detectors, “C-PODs”, recording Detection Positive Minutes per hour, at each end of gillnets, provided with the two pinger types or no pingers at all. Bycatch instances were recorded into logbooks by participating fishermen and verified using video footage from on-board video cameras. Results showed that video monitoring was a reliable method for verifying the number of bycatches of porpoises and seals, but not seabirds, recorded in the fishermen’s logbooks. The experimental SSB pingers and the FO pingers significantly reduced porpoise presence, measured as Detection Positive Minutes per hour in the vicinity of the nets, compared to gillnets without pingers. However, the sample size was too small to yield a significant result regarding the bycatch reducing efficiency and dinner bell effect of the experimental pingers. Nevertheless, bycatch trends suggest that pingers did in fact reduce porpoise bycatch. Although both successful, FO pingers were slightly more efficient in deterring porpoises than SSB pingers. The SSB pinger sounds had bigger directionality variations than the FO pinger, which may have affected its deterrent effects. Therefore, additional trials are needed to further investigate this aspect.

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  • 44.
    Blomlöf, Isabella
    Linköping University, Department of Physics, Chemistry and Biology.
    Hur påverkade den torra sommaren 2018 bottenfaunans artdiversitet, individtäthet och den ekologiska statusen i vattendrag i södra Sverige?2020Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    During the summer of 2018 Northern Europe, including Sweden, was affected by extremely high temperature and drought. The drought affected the society and environment that we and other organisms live in. Streams are one of the ecosystems sensible to these conditions. Long periods of drought may affect the waterflow or cause desiccation of streams. Since streams provide important ecological services, they are equally important to humans as to organisms living in them. In this study I investigate whether the dry summer of 2018 had any effect on the species diversity, density of individuals and ecological status in 16 randomly chosen southern Swedish streams. This was done by comparing number of species, average number of individuals per sample, ASPT- and MISA-indices in 2018 with reference years 2007–2017. In addition to this, I investigated whether the independent variables geographical location, pH and alkalinity had any effect on the deviation of 2018 compared to the reference years. The results showed that there were no significant differences between 2018 and the reference years for any of the variables. Thus, the dry summer of 2018 had no general effect. However, the southernmost streams generally generated negative deviations, while northern generally generated positive ones for average number of individuals per sample. To further understand how drought affects benthic invertebrates in streams that are not fully dried out further research should be conducted to examine how the composition of species is affected.

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  • 45.
    Bogstedt, Carl
    Linköping University, Department of Physics, Chemistry and Biology.
    How do corridors connecting two separated landscapes affect the ability of trophic metacommunities to survive habitat loss?2021Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [en]

    With an increasing worldwide infrastructure more habitats are fragmented by roads and buildings, which can cause a reduction in biodiversity up to 75%. One way to counteract this is by predicting the outcome, with the help of theoretical models, before it happens. In this study I used a Bayesian network model on a fragmented landscape, to test how well trophic metacommunities are able to persist habitat loss, when increasing dispersal between the fragments in the landscapes by implementing corridors. By implementing just three corridors, the species with the highest trophic level went extinct at a considerable later stage, and by just implementing 10 corridors, the metapopulation capacity for all species in all trophic levels increased. Similar results were obtained when changing the way the species extinction probabilities react to their resources being extinct, which further strengthen the efficacy of corridors. The results from this study suggests that increasing connectivity between landscape fragments, and therefore promoting dispersal of organisms, would help the conservation of biodiversity.

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  • 46.
    Bosshard, Tiffany Claire
    et al.
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering. German Primate Ctr, Germany.
    Salazar, Laura Teresa Hernandez
    Univ Veracruzana, Mexico.
    Laska, Matthias
    Linköping University, Department of Physics, Chemistry and Biology, Biology. Linköping University, Faculty of Science & Engineering.
    Numerical cognition in black-handed spider monkeys (Ateles geoffroyi)2022In: Behavioural Processes, ISSN 0376-6357, E-ISSN 1872-8308, Vol. 201, article id 104734Article in journal (Refereed)
    Abstract [en]

    We assessed two aspects of numerical cognition in a group of nine captive spider monkeys (Ateles geoffroyi). Petri dishes with varying amounts of food were used to assess relative quantity discrimination, and boxes fitted with dotted cards were used to assess discrete number discrimination with equally-sized dots and various-sized dots, respectively. We found that all animals succeeded in all three tasks and, as a group, reached the learning criterion of 70% correct responses within 110 trials in the quantity discrimination task, 160 trials in the numerosity task with equally-sized dots, and 30 trials in the numerosity task with various-sized dots. In all three tasks, the an-imals displayed a significant correlation between performance in terms of success rate and task difficulty in terms of numerical similarity of the stimuli and thus a ratio effect. The spider monkeys performed clearly better compared to strepsirrhine, catarrhine, and other platyrrhine primates tested previously on both types of nu-merical cognition tasks and at the same level as chimpanzees, bonobos, and orangutans. Our results support the notion that ecological traits such as a high degree of frugivory and/or social traits such as a high degree of fission-fusion dynamics may underlie between-species differences in cognitive abilities.

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  • 47.
    Boström, Sofie
    Linköping University, Department of Physics, Chemistry and Biology, Biology.
    Mängden åkermark och blommors påverkan på specialist- och generalistpollinatörer över tid2022Independent thesis Basic level (degree of Bachelor), 10,5 credits / 16 HE creditsStudent thesis
    Abstract [sv]

    Det intensifierade jordbruket har en betydande påverkan på pollinatörer och det har resulterat i att både fjärilsarter och humlearter har påverkats negativt. Beroende på om arten är en specialistart eller en generalistart skulle det kunna ha en inverkan på hur pass känslig den är för sin omgivning. Humlorna i denna studie har delats in i grupperna generalist och specialist beroende på deras tunglängd och fjärilarna har delats in i likadana grupper fast i stället beroende på antal värdväxter. Med hjälp av data över humlor och fjärilar som samlats in i ängs- och betesmarker i södra Sverige, har denna studie undersökt hur specialister och generalister påverkas av mängden åkermarker i närliggande område över de senaste 15 åren. Resultaten visade på att mängden åkermark inte hade någon signifikant effekt på förändringen i antal individer över tid hos vare sig specialisterna eller generalisterna, det visade i stället på att blomtätheten hade en signifikant effekt både hos specialister och generalister. Anledningen till att mängden åkermark inte hade någon signifikant effekt skulle kunna bero på flera saker. Exempelvis att de områden som fanns runt omkring åkermarkerna, så som gräskanterna som delar av mellan åkermarker eller mellan väg och åkermark, var tillräckligt blomrika för att kompensera för åkermarkerna. Eller så skulle det kunna bero på att storlekarna på ängs- och betesmarkerna var tillräckligt stora för att åkermarkerna inte skulle ha en signifikant effekt på pollinatörerna.

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  • 48.
    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)
  • 49.
    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.

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  • 50.
    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.

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