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  • 1.
    Aad, G.
    et al.
    Aix Marseille Univ, CPPM, CNRS IN2P3, Marseille, France..
    Leopold, Alexander
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Lundberg, Olof
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Lund-Jensen, Bengt
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Ohm, Christian
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Ripellino, Giulia
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Shaheen, Rabia
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Shope, David R.
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Strandberg, Jonas
    KTH, School of Engineering Sciences (SCI), Physics, Particle and Astroparticle Physics.
    Zwalinski, L.
    CERN, Geneva, Switzerland..
    et al.,
    Search for invisible Higgs-boson decays in events with vector-boson fusion signatures using 139 fb(-1) of proton-proton data recorded by the ATLAS experiment2022In: Journal of High Energy Physics (JHEP), ISSN 1126-6708, E-ISSN 1029-8479, no 8, article id 104Article in journal (Refereed)
    Abstract [en]

    A direct search for Higgs bosons produced via vector-boson fusion and subsequently decaying into invisible particles is reported. The analysis uses 139 fb(-1) of pp collision data at a centre-of-mass energy of root s =13 TeV recorded by the ATLAS detector at the LHC. The observed numbers of events are found to be in agreement with the background expectation from Standard Model processes. For a scalar Higgs boson with a mass of 125 GeV and a Standard Model production cross section, an observed upper limit of 0.145 is placed on the branching fraction of its decay into invisible particles at 95% confidence level, with an expected limit of 0.103. These results are interpreted in the context of models where the Higgs boson acts as a portal to dark matter, and limits are set on the scattering cross section of weakly interacting massive particles and nucleons. Invisible decays of additional scalar bosons with masses from 50 GeV to 2 TeV are also studied, and the derived upper limits on the cross section times branching fraction decrease with increasing mass from 1.0 pb for a scalar boson mass of 50 GeV to 0.1 pb at a mass of 2 TeV.

  • 2.
    Aalberg Haugen, Inger M.
    et al.
    Stockholm University, Faculty of Science, Department of Zoology.
    Berger, David
    Stockholm University, Faculty of Science, Department of Zoology. Uppsala University, Sweden.
    Gotthard, Karl
    Stockholm University, Faculty of Science, Department of Zoology.
    The evolution of alternative developmental pathways: footprints of selection on life-history traits in a butterfly2012In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 25, no 7, p. 1377-1388Article in journal (Refereed)
    Abstract [en]

    Developmental pathways may evolve to optimize alternative phenotypes across environments. However, the maintenance of such adaptive plasticity under relaxed selection has received little study. We compare the expression of life-history traits across two developmental pathways in two populations of the butterfly Pararge aegeria where both populations express a diapause pathway but one never expresses direct development in nature. In the population with ongoing selection on both pathways, the difference between pathways in development time and growth rate was larger, whereas the difference in body size was smaller compared with the population experiencing relaxed selection on one pathway. This indicates that relaxed selection on the direct pathway has allowed life-history traits to drift towards values associated with lower fitness when following this pathway. Relaxed selection on direct development was also associated with a higher degree of genetic variation for protandry expressed as within-family sexual dimorphism in growth rate. Genetic correlations for larval growth rate across sexes and pathways were generally positive, with the notable exception of correlation estimates that involved directly developing males of the population that experienced relaxed selection on this pathway. We conclude that relaxed selection on one developmental pathway appears to have partly disrupted the developmental regulation of life-history trait expression. This in turn suggests that ongoing selection may be responsible for maintaining adaptive developmental regulation along alternative developmental pathways in these populations.

  • 3.
    Aalto, Anders
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Biodiversity and habitat conditions in reaches with high flow velocity along gradients in hydrological and geomorphological alteration: A study of six rivers in Sweden2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The vast majority of rivers in the developed world are affected by human alteration, which in turn negatively affects the species that rely on these highly diverse and species rich areas to survive. Homogenization of previously heterogenic areas due to a change in water discharge and the substrate availability in the rivers is often regarded as the main reason for the loss of species richness in rivers and the riparian zone. Because of this, there are a lot of restoration projects which main goal is to increase heterogeneity. The goal of this thesis is to compare hydrology and geomorphology variables between four types of reaches with high flow velocity (rapids in free-flowing reaches, rapids with regulated flow, impounded reaches and reaches in outlet channels below hydropower plants). In this thesis I wanted to find out how changes in geomorphology and hydrology affect fish species richness, riparian vegetation richness and aquatic vascular plants species richness. The result show that both fish species richness and riparian vegetation species richness are negatively affected by the changes in geomorphology and hydrology. There was no significant difference for aquatic vascular plants when comparing the regulation types. The most altered reach type, outlet channels, had significantly fewer fish species compared to the less altered reach type, impounded reaches. Outlet channels also had less riparian vegetation cover compared to all other regulation types, and fewer riparian vegetation species compared to both free-flowing reaches and impounded reaches. In conclusion, hydropower plants and timber floating have both negatively impacted the riverine ecosystem, and in turn caused a decrease in species richness for fish and riparian plants. The reaches studied in this thesis will continue to be altered and the species richness and species composition will change from an ecosystem that relied on the natural flow regime to an ecosystem more used to the flow regime created by the hydropower plants. 

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  • 4. Aarrestad, P. A.
    et al.
    Hytteborn, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution.
    Masunga, G.
    Skarpe, C.
    Vegetation: Between Soils and Herbivores2014In: Elephants and Savanna Woodland Ecosystems: A Study from Chobe National Park, Botswana / [ed] Christina Skarpe, Johan T. du Toit and Stein R. Moe, Wiley-Blackwell, 2014, p. 61-88Chapter in book (Refereed)
    Abstract [en]

    The vegetation of the study area in Chobe National Park is influenced by a range of factors, including inundation by the Chobe River, soil moisture and fertility, and the impacts of different-size grazers and browsers. This chapter focuses on how the structure and species composition of the present vegetation in northern Chobe National Park is related to recent herbivory by elephants, as agents shaping the vegetation, and by mesoherbivores acting as controllers or responders, along with abiotic controllers such as soil type and distance to the river. In the study, a two-way indicator species analysis classified the vegetation data into four more or less distinct plant community groups (i) Baikiaea plurijuga-Combretum apiculatum woodland, (ii) Combretum mossambicense-Friesodielsia obovata wooded shrubland, (iii) Capparis tomentosa-Flueggea virosa shrubland and (iv) Cynodon dactylon-Heliotropium ovalifolium floodplain, named after the TWINSPAN indicator or preferential species with high cover, and the relative amount of shrubs and trees.

  • 5. Abafe, Ovokeroye A.
    et al.
    Späth, Jana
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Fick, Jerker
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Jansson, Stina
    Umeå University, Faculty of Science and Technology, Department of Chemistry.
    Buckley, Chris
    Stark, Annegret
    Pietruschka, Bjoern
    Martincigh, Bice S.
    LC-MS/MS determination of antiretroviral drugs in influents and effluents from wastewater treatment plants in KwaZulu-Natal, South Africa2018In: Chemosphere, ISSN 0045-6535, E-ISSN 1879-1298, Vol. 200, p. 660-670Article in journal (Refereed)
    Abstract [en]

    South Africa has the largest occurrence of the human immune deficiency virus (HIV) in the world but has also implemented the largest antiretroviral (ARV) treatment programme. It was therefore of interest to determine the presence and concentrations of commonly used antiretroviral drugs (ARVDs) and, also, to determine the capabilities of wastewater treatment plants (WWTPs) for removing ARVDs. To this end, a surrogate standard based LC-MS/MS method was optimized and applied for the detection of thirteen ARVDs used in the treatment and management of HIV/acquired immune deficiency syndrome (HIV/AIDS) in two major and one modular WWTP in the eThekwini Municipality in KwaZulu-Natal, South Africa. The method was validated and the detection limits fell within the range of 2–20 ng L−1. The analytical recoveries for the ARVDs were mainly greater than 50% with acceptable relative standard deviations. The concentration values ranged from <LOD – 53000 ng L−1 (influent), <LOD – 34000 ng L−1 (effluent) in a decentralized wastewater treatment facility (DEWATS); <LOD – 24000 ng L−1 (influent), <LOD – 33000 ng L−1 (effluent) in Northern WWTP and 61–34000 ng L−1 (influent), <LOD – 20000 ng L−1 (effluent) in Phoenix WWTP. Whilst abacavir, lamivudine and zidovudine were almost completely removed from the effluents, atazanavir, efavirenz, lopinavir and nevirapine persisted in the effluents from all three WWTPs. To estimate the ecotoxicological risks associated with the discharge of ARVDs, a countrywide survey focussing on the occurrence of ARVDs in WWTPs, surface and fresh water bodies, and aquatic organisms, is necessary.

  • 6.
    Abascal, Angela
    et al.
    University of Navarra, Spain; University of Twente, Netherlands.
    Georganos, Stefanos
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    Kuffer, Monika
    University of Twente, Netherlands.
    Vanhuysse, Sabine
    Université libre de Bruxelles (ULB), Belgium.
    Thomson, Dana
    University of Twente, Netherlands.
    Wang, Jon
    University of Twente, Netherlands.
    Manyasi, Lawrence
    Community Researcher Non-affiliated, Nairobi, Kenya.
    Otunga, Daniel Manyasi
    Community Researcher Single Mother Association of Kenya, Nairobi, Kenya.
    Ochieng, Brighton
    Community Researcher Non-affiliated, Nairobi, Kenya.
    Ochieng, Treva
    Community Researcher Non-affiliated, Nairobi, Kenya.
    Klinnert, Jorge
    University of Maryland, USA.
    Wolff, Eléonore
    Université libre de Bruxelles (ULB), Belgium.
    Making Urban Slum Population Visible: Citizens and Satellites to Reinforce Slum Censuses2024In: Urban Inequalities from Space: Earth Observation Applications in the Majority World / [ed] Monika Kuffer, Stefanos Georganos, Springer, 2024, Vol. 26, p. 287-302Chapter in book (Refereed)
    Abstract [en]

    In response to the “Leave No One Behind” principle (the central promise of the 2030 Agenda for Sustainable Development), reliable estimate of the total number of citizens living in slums is urgently needed but not available for some of the most vulnerable communities. Not having a reliable estimate of the number of poor urban dwellers limits evidence-based decision-making for proper resource allocation in the fight against urban inequalities. From a geographical perspective, urban population distribution maps in many low- and middle-income cities are most often derived from outdated or unreliable census data disaggregated by coarse administrative units. Moreover, slum populations are presented as aggregated within bigger administrative areas, leading to a large diffuse in the estimates. Existing global and open population databases provide homogeneously disaggregated information (i.e. in a spatial grid), but they mostly rely on census data to generate their estimates, so they do not provide additional information on the slum population. While a few studies have focused on bottom-up geospatial models for slum population mapping using survey data, geospatial covariates, and earth observation imagery, there is still a significant gap in methodological approaches for producing precise estimates within slums. To address this issue, we designed a pilot experiment to explore new avenues. We conducted this study in the slums of Nairobi, where we collected in situ data together with slum dwellers using a novel data collection protocol. Our results show that the combination of satellite imagery with in situ data collected by citizen science paves the way for generalisable, gridded estimates of slum populations. Furthermore, we find that the urban physiognomy of slums and population distribution patterns are related, which allows for highlighting the diversity of such patterns using earth observation within and between slums of the same city. 

  • 7.
    Abbasi, Saeed
    et al.
    KTH Royal Inst Technol, Dept Machine Design, Stockholm, Sweden.
    Jansson, Anders
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Sellgren, Ulf
    KTH Royal Inst Technol, Dept Machine Design, Stockholm, Sweden.
    Olofsson, Ulf
    KTH Royal Inst Technol, Dept Machine Design, Stockholm, Sweden.
    Particle Emissions From Rail Traffic: A Literature Review2013In: Critical reviews in environmental science and technology, ISSN 1064-3389, E-ISSN 1547-6537, Vol. 43, no 23, p. 2511-2544Article, review/survey (Refereed)
    Abstract [en]

    Particle emissions are a drawback of rail transport. This work is a comprehensive presentation of recent research into particle emissions from rail vehicles. Both exhaust and nonexhaust particle emissions are considered when examining particle characteristics such as PM10, and PM2.5 concentration levels, size, morphology, composition, and adverse health effects, current legislation, and available and proposed solutions for reducing such emissions. High concentration levels in enclosed rail traffic environments are reported and some toxic effects of the particles. The authors find that only a few limited studies have examined the adverse health effects of nonexhaust particle emissions and that no relevant legislation exists. Thus further research in this area is warranted.

  • 8. Abbasi, Umar Aftab
    et al.
    Mattsson, Eskil
    IVL Swedish Environmental Research Institute.
    Nissanka, Sarath Premalal
    Ali, Arshad
    Biological, structural and functional responses of tropical forests to environmental factors2022In: Biological Conservation, ISSN 0006-3207, E-ISSN 1873-2917, Vol. 276, p. 109792-109792, article id 109792Article in journal (Refereed)
    Abstract [en]

    Here, we hypothesize that the biological, structural and functional attributes of tropical forests respond to water-related climatic and soil nutrient-related factors.

    Thus, we quantified 27 forest attributes and 20 environmental factors across 189 plots of Sri Lankan tropical forests. Our results suggest that environmental conditions were characterized by both water-related and temperature-related factors, and as such, both coarse-textured and compacted-structured soils determined soil conditions.

    Forest conditions were characterized by high species-functional diversity, structural complexity and aboveground biomass-related functions. We found strong positive effects of water-related climatic factors followed by temperature-related climatic factors but negligible positive to negative effects of textured-related and nutrient-related soil factors on most of the biological, structural and functional attributes.

    Overall the biodiversity and carbon stocks of Sri Lankan tropical forests are likely to increase with water-energy balance and improved soil conditions, and thus, studied forests could offset a substantial quantity of anthropogenic carbon emissions to achieve carbon neutrality which can have both regional and global significance if protected from anthropogenic disturbances. 

  • 9. Abbasi, Umar Aftab
    et al.
    Mattsson, Eskil
    IVL Swedish Environmental Research Institute.
    Nissanka, Sarath Premalal
    Ali, Arshad
    Species α-diversity promotes but β-diversity restricts aboveground biomass in tropical forests, depending on stand structure and environmental factors2022In: Journal of Forestry Research, ISSN 1007-662X, E-ISSN 1993-0607Article in journal (Refereed)
    Abstract [en]

    Forest plays a vital role in the global biogeochemical cycles through a high rate of carbon sequestration and harboring biodiversity. However, local species diversity is declining while also becoming increasingly homogenized across communities. Although effects of local biotic processes (e.g., species α-diversity and stand structural heterogeneity) and environmental factors on aboveground biomass (AGB) have been widely tested, there is a huge knowledge gap for the effect of regional biotic processes (i.e., taxonomic and functional β-diversity) in forests. Here, we hypothesized that regional and local environmental factors along with biotic processes jointly regulate AGB through species shifts in tropical forests.

    Using piecewise structural equation modeling (pSEM), we linked climatic water availability, soil fertility, stand structural heterogeneity (either tree DBH inequality, height inequality, or stand density), species α-diversity, taxonomic or functional β-diversity (and its two components; β-turnover and β-richness), and AGB across 189 inventory plots in tropical forests of Sri Lanka. Soil fertility and climatic water availability shaped local and regional biotic processes. Stand structural heterogeneity promoted species α-diversity but declined β-diversity (but increased β-taxonomic turnover). Species α-diversity and stand structural heterogeneity promoted AGB whereas taxonomic and functional β-diversity declined (but β-taxonomic turnover increased) AGB.

    The relationships of AGB with species α-diversity and β-diversity varied from significant to nonsignificant positive depending on the specific combinations of stand structural heterogeneity metrics used. This study shows that local biotic processes could increase AGB due to the local and regional niche complementarity effect whereas the regional biotic processes could restrict AGB due to the regional selection or functional redundancy effect under favorable environmental conditions. We argue that biotic homogenization, as well as drought conditions, may have strong divergent impacts on forest functions and that the impacts of tree diversity loss may greatly reduce carbon sequestration.

  • 10.
    Abbott, Jessica K.
    et al.
    Lund University.
    Chippindale, Adam K.
    Queens University, Kingston, CAN.
    Morrow, Edward H. (Ted)
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013).
    The microevolutionary response to male-limited X-chromosome evolution in Drosophila melanogaster reflects macroevolutionary patterns2020In: Journal of Evolutionary Biology, ISSN 1010-061X, E-ISSN 1420-9101, Vol. 33, no 6, p. 738-750Article in journal (Refereed)
    Abstract [en]

    Due to its hemizygous inheritance and role in sex determination, the X-chromosome is expected to play an important role in the evolution of sexual dimorphism and to be enriched for sexually antagonistic genetic variation. By forcing the X-chromosome to only be expressed in males over >40 generations, we changed the selection pressures on the X to become similar to those experienced by the Y. This releases the X from any constraints arising from selection in females and should lead to specialization for male fitness, which could occur either via direct effects of X-linked loci or trans-regulation of autosomal loci by the X. We found evidence of masculinization via up-regulation of male-benefit sexually antagonistic genes and down-regulation of X-linked female-benefit genes. Potential artefacts of the experimental evolution protocol are discussed and cannot be wholly discounted, leading to several caveats. Interestingly, we could detect evidence of microevolutionary changes consistent with previously documented macroevolutionary patterns, such as changes in expression consistent with previously established patterns of sexual dimorphism, an increase in the expression of metabolic genes related to mito-nuclear conflict and evidence that dosage compensation effects can be rapidly altered. These results confirm the importance of the X in the evolution of sexual dimorphism and as a source for sexually antagonistic genetic variation and demonstrate that experimental evolution can be a fruitful method for testing theories of sex chromosome evolution.

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  • 11.
    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.

  • 12.
    Abdel-Fattah, Dina
    et al.
    UiT – The Arctic University of Norway, Norway; University of Alaska Fairbanks, USA.
    Danielson, Mats
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences. International Institute for Applied Systems Analysis, Austria.
    Ekenberg, Love
    Stockholm University, Faculty of Social Sciences, Department of Computer and Systems Sciences. International Institute for Applied Systems Analysis, Austria.
    Hock, Regine
    University of Alaska Fairbanks, USA; University of Oslo, Norway.
    Trainor, Sarah
    University of Alaska Fairbanks, USA.
    Application of a structured decision-making process in cryospheric hazard planning: Case study of Bering Glacier surges on local state planning in Alaska2024In: Journal of Multi-Criteria Decision Analysis, ISSN 1057-9214, E-ISSN 1099-1360, Vol. 31, no 1-2, article id e1825Article in journal (Refereed)
    Abstract [en]

    Surging glaciers are glaciers that experience rapidly accelerated glacier flow over a comparatively short period of time. Though relatively rare worldwide, Alaska is home to the largest number of surge-type glaciers globally. However, their impact on the broader socioecological system in the state is both poorly understood and under-researched, which poses a challenge in developing appropriate sustainability decisions in Alaska. We investigated how the surge patterns of the Bering Glacier in Alaska have potentially devastating effects on the local ecological biodiversity of its watershed via a structured decision-making analysis of the different possible consequences. Specifically, this analysis was conducted to explore the various outcomes of a Bering Glacier surge particularly if humans have an increased presence near the glacier due to the area potentially becoming a state park. This work explored the benefits of applying a risk and decision analytical framework in a cryosphere context, to better understand the socioeconomic impact of glacier surges. This is a novel approach in which a decision analysis tool was used to better understand an environmental sustainability challenge, offering an innovative method to support the achievement of the United Nations Sustainability Development Goals in Alaska. We therefore emphasise the need for integrated biophysical and socioeconomic analyses when it comes to understanding glacier hazards. Our research highlights the importance of understanding and researching biophysical changes as well as using a structured decision-making process for complicated hazard planning scenarios, exemplified via glaciated regions in Alaska, in order to create adaptation strategies that are sustainable and encompass the range of possible outcomes.

  • 13.
    Abdelgadir, Mohanad
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science. Södertörn University, Centre for Baltic and East European Studies (CBEES), Baltic & East European Graduate School (BEEGS).
    Broman, Elias
    Stockholm University, Sweden.
    Bonaglia, Stefano
    Gothenburg University, Sweden.
    Nascimento, Francisco, J. A.
    Stockholm University, Sweden.
    Dinnétz, Patrik
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Sjöling, Sara
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Association between sediment denitrification rates, transcript abundances of denitrification genes and bacterial community compositionManuscript (preprint) (Other academic)
  • 14.
    Abdelgadir, Mohanad
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science. Södertörn University, Centre for Baltic and East European Studies (CBEES), Baltic & East European Graduate School (BEEGS).
    Broman, Elias
    Stockholm University, Sweden.
    Dinnétz, Patrik
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Sjöling, Sara
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Multiple realm models of marine, terrestrial, and future climate change scenarios predict increased filamentous cyanobacteria occurrences in coastal Baltic SeaManuscript (preprint) (Other academic)
  • 15.
    Abdelgadir, Mohanad
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science. Södertörn University, Centre for Baltic and East European Studies (CBEES), Baltic & East European Graduate School (BEEGS).
    Raymond, Caroline
    Stockholm University, Sweden.
    Sjöling, Sara
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Dinnétz, Patrik
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies, Environmental Science.
    Benthic denitrification capacity association with changes in habitat configuration in a small-scale systemManuscript (preprint) (Other academic)
  • 16.
    Abdel-Hameed, Amal Mohamed
    et al.
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza 12613, Egypt.
    Abuarab, Mohamed EL-Sayed
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza 12613, Egypt.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Mehawed, Hazem Sayed
    Irrigation and Drainage Department, Agricultural Engineering Research Institute, Giza 12613, Egypt.
    Kassem, Mohamed Abdelwahab
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza 12613, Egypt.
    He, Hongming
    School of Geographic Sciences, East China Normal University, Shanghai 210062, China.
    Gyasi-Agyei, Yeboah
    School of Engineering and Built Environment, Griffith University, Nathan, QLD 4111, Australia.
    Mokhtar, Ali
    Department of Agricultural Engineering, Faculty of Agriculture, Cairo University, Giza 12613, Egypt; School of Geographic Sciences, East China Normal University, Shanghai 210062, China.
    Winter Potato Water Footprint Response to Climate Change in Egypt2022In: Atmosphere, E-ISSN 2073-4433, Vol. 13, no 7, article id 1052Article in journal (Refereed)
    Abstract [en]

    The limited amount of freshwater is the most important challenge facing Egypt due to increasing population and climate change. The objective of this study was to investigate how climatic change affects the winter potato water footprint at the Nile Delta covering 10 governorates from 1990 to 2016. Winter potato evapotranspiration (ETC) was calculated based on daily climate variables of minimum temperature, maximum temperature, wind speed and relative humidity during the growing season (October–February). The Mann–Kendall test was applied to determine the trend of climatic variables, crop evapotranspiration and water footprint. The results showed that the highest precipitation values were registered in the northwest governorates (Alexandria followed by Kafr El-Sheikh). The potato water footprint decreased from 170 m3 ton−1 in 1990 to 120 m3 ton−1 in 2016. The blue-water footprint contributed more than 75% of the total; the remainder came from the green-water footprint. The findings from this research can help government and policy makers better understand the impact of climate change on potato crop yield and to enhance sustainable water management in Egypt’s major crop-producing regions to alleviate water scarcity.

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  • 17.
    Abderhalden, Bigna Lu
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Seasonal Reindeer Grazing Effects on Mountain Birch Forests: A 3D Perspective using Drones2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Reindeer are important drivers of ecosystem processes in arctic and subarctic ecosystems, changing nutrient conditions and influencing vegetation by grazing and trampling. Mountain birch forests are one of the ecosystems impacted by reindeer grazing, but the effect on the 3D structure of these forests is not well understood. Drones are revolutionising ecological studies, allowing to create high-resolution 3D point clouds at low costs. I investigated the effect of year-round and autumn reindeer grazing on mountain birch forest vegetation in historically separated grazing areas at the Finnish-Norwegian border, using a combination of field data and drone data. The two sampling techniques were further compared to evaluate the possibility to use photogrammetric point clouds to characterise mountain birch forests. I found lower productivity in the year-round grazing regime, coinciding with generally higher vegetation density. Vertically, higher densities were found above browsing height, while the understory showed lower densities compared to autumn grazed areas. These results suggest that mountain birches allocate more biomass to the canopy area, which can be direct or indirect grazing effects. Nevertheless, overall productivity is lowered by grazing indicating changes in vegetation biomass and composition. The point clouds generally matched field data, but the understory vegetation tended to be underrepresented, arising the question if found effects are ecological or technical. As this could not be disentangled, cautious interpretation of my results is required. I conclude that using photogrammetric point clouds is a promising technique for ecological studies, but needs further development to improve accuracy and reliability of results.

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  • 18. Abeli, Thomas
    et al.
    Orsenigo, Simone
    Guzzon, Filippo
    Fae, Matteo
    Balestrazzi, Alma
    Carlsson-Graner, Ulla
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Mueller, Jonas V.
    Mondoni, Andrea
    Geographical pattern in the response of the arctic-alpine Silene suecica (Cariophyllaceae) to the interaction between water availability and photoperiod2015In: Ecological research, ISSN 0912-3814, E-ISSN 1440-1703, Vol. 30, no 2, p. 327-335Article in journal (Refereed)
    Abstract [en]

    We hypothesized a geographical pattern of the plant performance (seedling development, biomass production, relative water content and chlorophyll content) as a result of response to the interaction between photoperiod and water availability in populations of the arctic-alpine Silene suecica from different latitudes, thus experiencing different photoperiods during the growing season. Particularly, we expected a lower drought sensitivity in northern compared to southern populations as a consequence of harsher conditions experienced by the northern populations in terms of water availability. The experiment was carried out under common garden conditions, manipulating the water availability (wet and dry) and the photoperiod (21 and 16 h). We found an interaction between photoperiod and water availability on plant height, leaves, growth, biomass and total chlorophyll. However, the photoperiod neither counteracted nor intensified the effect of drought. Plants exposed to drought compensated for decreasing water availability by reducing their shoot growth. Changes in the chlorophyll content and chlorophyll a/b ratio were observed. Northern populations showed a higher basal growth performance and a greater response to the changed water regime (from wet to dry) than the southern populations. Southern populations showed a reduced ability to respond to drought, but their low basal performance may be advantageous under low water availability, avoiding water loss. In contrast, northern populations showed a stronger plastic response that limited the negative effects of reduced water availability. This study highlights the possibility that the plant response to environmental constraints (specifically water availability) may follow a geographical pattern.

  • 19.
    Abeysinghe, Kasun S.
    et al.
    Chinese Acad Sci, Xishuangbanna Trop Bot Garden, Key Lab Trop Forest Ecol, Mengla, Yunnan, Peoples R China.;Univ Chinese Acad Sci, Beijing, Peoples R China..
    Yang, Xiao-Dong
    Chinese Acad Sci, Xishuangbanna Trop Bot Garden, Key Lab Trop Forest Ecol, Mengla, Yunnan, Peoples R China..
    Goodale, Eben
    Guangxi Univ, Coll Forestry, Nanning, Guangxi, Peoples R China..
    Anderson, Christopher W. N.
    Massey Univ, Inst Agr & Environm, Soil & Earth Sci, Palmerston North, New Zealand..
    Bishop, Kevin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL. Swedish Univ Agr Sci, Dept Aquat Sci & Assessment, Uppsala, Sweden..
    Cao, Axiang
    Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang, Peoples R China.;Guizhou Normal Univ, Sch Chem & Mat Sci, Guiyang, Peoples R China..
    Feng, Xinbin
    Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang, Peoples R China..
    Liu, Shengjie
    Chinese Acad Sci, Xishuangbanna Trop Bot Garden, Key Lab Trop Forest Ecol, Mengla, Yunnan, Peoples R China.;Univ Chinese Acad Sci, Beijing, Peoples R China..
    Mammides, Christos
    Chinese Acad Sci, Xishuangbanna Trop Bot Garden, Key Lab Trop Forest Ecol, Mengla, Yunnan, Peoples R China..
    Meng, Bo
    Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang, Peoples R China..
    Quan, Rui-Chang
    Chinese Acad Sci, Xishuangbanna Trop Bot Garden, Key Lab Trop Forest Ecol, Mengla, Yunnan, Peoples R China..
    Sun, Jing
    Nanjing Agr Univ, Coll Resources & Environm Sci, Nanjing, Jiangsu, Peoples R China..
    Qiu, Guangle
    Chinese Acad Sci, Inst Geochem, State Key Lab Environm Geochem, Guiyang, Peoples R China..
    Total mercury and methylmercury concentrations over a gradient of contamination in earthworms living in rice paddy soil2017In: Environmental Toxicology and Chemistry, ISSN 0730-7268, E-ISSN 1552-8618, Vol. 36, no 5, p. 1202-1210Article in journal (Refereed)
    Abstract [en]

    Mercury (Hg) deposited from emissions or from local contamination, can have serious health effects on humans and wildlife. Traditionally, Hg has been seen as a threat to aquatic wildlife, because of its conversion in suboxic conditions into bioavailable methylmercury (MeHg), but it can also threaten contaminated terrestrial ecosystems. In Asia, rice paddies in particular may be sensitive ecosystems. Earthworms are soil-dwelling organisms that have been used as indicators of Hg bioavailability; however, the MeHg concentrations they accumulate in rice paddy environments are not well known. Earthworm and soil samples were collected from rice paddies at progressive distances from abandoned mercury mines in Guizhou, China, and at control sites without a history of Hg mining. Total Hg (THg) and MeHg concentrations declined in soil and earthworms as distance increased from the mines, but the percentage of THg that was MeHg, and the bioaccumulation factors in earthworms, increased over this gradient. This escalation in methylation and the incursion of MeHg into earthworms may be influenced by more acidic soil conditions and higher organic content further from the mines. In areas where the source of Hg is deposition, especially in water-logged and acidic rice paddy soil, earthworms may biomagnify MeHg more than was previously reported. It is emphasized that rice paddy environments affected by acidifying deposition may be widely dispersed throughout Asia.

  • 20.
    Abreu, Clare I.
    et al.
    Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA; Department of Biology, Stanford University, Stanford, CA, USA.
    Bello, Martina Dal
    Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.
    Bunse, Carina
    Department of Marine Sciences, University of Gothenburg, Gothenburg, Sweden.
    Pinhassi, Jarone
    Centre for Ecology and Evolution of Microbial Model Systems, Department of Biology and Environmental Science, Linnaeus University, Kalmar, Sweden.
    Gore, Jeff
    Physics of Living Systems, Department of Physics, Massachusetts Institute of Technology, Cambridge, MA, USA.
    Warmer temperatures favor slower-growing bacteria in natural marine communities2023In: Science Advances, E-ISSN 2375-2548, Vol. 9, no 19, article id eade8352Article in journal (Refereed)
    Abstract [en]

    Earth’s life-sustaining oceans harbor diverse bacterial communities that display varying composition across time and space. While particular patterns of variation have been linked to a range of factors, unifying rules are lacking, preventing the prediction of future changes. Here, analyzing the distribution of fast- and slow-growing bacteria in ocean datasets spanning seasons, latitude, and depth, we show that higher seawater temperatures universally favor slower-growing taxa, in agreement with theoretical predictions of how temperature-dependent growth rates differentially modulate the impact of mortality on species abundances. Changes in bacterial community structure promoted by temperature are independent of variations in nutrients along spatial and temporal gradients. Our results help explain why slow growers dominate at the ocean surface, during summer, and near the tropics and provide a framework to understand how bacterial communities will change in a warmer world.

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  • 21.
    Abreu, Clare I.
    et al.
    MIT, USA;Stanford Univ, USA.
    Dal Bello, Martina
    MIT, USA.
    Bunse, Carina
    University of Gothenburg, Sweden.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Gore, Jeff
    MIT, USA.
    Warmer temperatures favor slower-growing bacteria in natural marine communities2023In: Science Advances, E-ISSN 2375-2548, Vol. 9, no 19, article id 26eade8352Article in journal (Refereed)
    Abstract [en]

    Earth's life-sustaining oceans harbor diverse bacterial communities that display varying composition across time and space. While particular patterns of variation have been linked to a range of factors, unifying rules are lacking, preventing the prediction of future changes. Here, analyzing the distribution of fast- and slowgrowing bacteria in ocean datasets spanning seasons, latitude, and depth, we show that higher seawater temperatures universally favor slower-growing taxa, in agreement with theoretical predictions of how temperaturedependent growth rates differentially modulate the impact of mortality on species abundances. Changes in bacterial community structure promoted by temperature are independent of variations in nutrients along spatial and temporal gradients. Our results help explain why slow growers dominate at the ocean surface, during summer, and near the tropics and provide a framework to understand how bacterial communities will change in a warmer world.

  • 22.
    Abreu, Murilo S.
    et al.
    Fed Univ Santa Maria UFSM, Grad Program Pharmacol, BR-97105900 Santa Maria, RS, Brazil.
    Messias, Joao P. M.
    Univ Porto, Ctr Invest Biodiversidade & Recursos Genet, CIBIO, Campus Agr Vairao, P-4485661 Vairao, Portugal.
    Thörnqvist, Per-Ove
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Physiology.
    Winberg, Svante
    Uppsala University, Disciplinary Domain of Medicine and Pharmacy, Faculty of Medicine, Department of Neuroscience, Physiology.
    Soares, Marta C.
    Univ Porto, Ctr Invest Biodiversidade & Recursos Genet, CIBIO, Campus Agr Vairao, P-4485661 Vairao, Portugal.
    Monoaminergic levels at the forebrain and diencephalon signal for the occurrence of mutualistic and conspecific engagement in client reef fish2018In: Scientific Reports, E-ISSN 2045-2322, Vol. 8, article id 7346Article in journal (Refereed)
    Abstract [en]

    Social interactions are commonly found among fish as in mammals and birds. While most animals interact socially with conspecifics some however are also frequently and repeatedly observed to interact with other species (i.e. mutualistic interactions). This is the case of the (so-called) fish clients that seek to be cleaned by other fish (the cleaners). Clients face an interesting challenge: they raise enough motivation to suspend their daily activities as to selectively visit and engage in interactions with cleaners. Here we aimed, for the first time, to investigate the region-specific brain monoaminergic level differences arising from individual client fish when facing a cleaner (interspecific context) compared to those introduced to another conspecific (socio-conspecific context). We show that monoaminergic activity differences occurring at two main brain regions, the diencephalon and the forebrain, are associated with fish clients' social and mutualistic activities. Our results are the first demonstration that monoaminergic mechanisms underlie client fish mutualistic engagement with cleanerfish. These pathways should function as a pre-requisite for cleaning to occur, providing to clients the cognitive and physiological tools to seek to be cleaned.

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  • 23. Abs, Elsa
    et al.
    Chase, Alexander B.
    Manzoni, Stefano
    Stockholm University, Faculty of Science, Department of Physical Geography. Stockholm University, Faculty of Science, The Bolin Centre for Climate Research (together with KTH & SMHI).
    Ciais, Philippe
    Allison, Steven D.
    Microbial evolution—An under-appreciated driver of soil carbon cycling2024In: Global Change Biology, ISSN 1354-1013, E-ISSN 1365-2486, Vol. 30, no 4, article id e17268Article in journal (Refereed)
    Abstract [en]

    Although substantial advances in predicting the ecological impacts of global change have been made, predictions of the evolutionary impacts have lagged behind. In soil ecosystems, microbes act as the primary energetic drivers of carbon cycling; however, microbes are also capable of evolving on timescales comparable to rates of global change. Given the importance of soil ecosystems in global carbon cycling, we assess the potential impact of microbial evolution on carbon-climate feedbacks in this system. We begin by reviewing the current state of knowledge concerning microbial evolution in response to global change and its specific effect on soil carbon dynamics. Through this integration, we synthesize a roadmap detailing how to integrate microbial evolution into ecosystem biogeochemical models. Specifically, we highlight the importance of microscale mechanistic soil carbon models, including choosing an appropriate evolutionary model (e.g., adaptive dynamics, quantitative genetics), validating model predictions with ‘omics’ and experimental data, scaling microbial adaptations to ecosystem level processes, and validating with ecosystem-scale measurements. The proposed steps will require significant investment of scientific resources and might require 10–20 years to be fully implemented. However, through the application of multi-scale integrated approaches, we will advance the integration of microbial evolution into predictive understanding of ecosystems, providing clarity on its role and impact within the broader context of environmental change.

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  • 24. Abunge, Caroline
    et al.
    Coulthard, Sarah
    Daw, Tim M.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Connecting Marine Ecosystem Services to Human Well-being: Insights from Participatory Well-being Assessment in Kenya2013In: Ambio, ISSN 0044-7447, E-ISSN 1654-7209, Vol. 42, no 8, p. 1010-1021Article in journal (Refereed)
    Abstract [en]

    The linkage between ecosystems and human well-being is a focus of the conceptualization of ecosystem services as promoted by the Millennium Ecosystem Assessment. However, the actual nature of connections between ecosystems and the well-being of individuals remains complex and poorly understood. We conducted a series of qualitative focus groups with five different stakeholder groups connected to a small-scale Kenyan coastal fishery to understand (1) how well-being is understood within the community, and what is important for well-being, (2) how people's well-being has been affected by changes over the recent past, and (3) people's hopes and aspirations for their future fishery. Our results show that people conceive well-being in a diversity of ways, but that these can clearly map onto the MA framework. In particular, our research unpacks the freedoms and choices element of the framework and argues for greater recognition of these aspects of well-being in fisheries management in Kenya through, for example, more participatory governance processes.

  • 25.
    Ackefors, Hans
    Stockholm University, Faculty of Science, Department of Zoology, Animal Ecology.
    Global fisheries - threats and opportunities2009In: Fisheries, sustainablity and development: fifty-two authors on coexistence and development of fisheries and aquaculture in developing and developed countries / [ed] Per Wramner, Hans Ackefors et al, Stockholm: Kungl. Skogs- och lantbruksakademien , 2009, p. 35-68-Chapter in book (Other academic)
  • 26.
    Ackefors, Hans
    Stockholm University, Faculty of Science, Department of Zoology, Animal Ecology.
    Är det politikerna eller fiskenäringen som styr fisket?2008In: Kungl. Skogs- och Lantbruksakademiens Tidskrift, ISSN 0023-5350, Vol. 147, no 2, p. 36-43Article in journal (Other (popular science, discussion, etc.))
  • 27.
    Ackerfors, Viktoria
    Linnaeus University, Faculty of Technology, Department of Forestry and Wood Technology.
    Vilken inställning har Länsstyrelserna till naturvårdsbränningar i områden med fornlämningar och övriga kulturhistoriska lämningar?2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Skogsbränderna har en stor betydelse för den biologiska mångfalden. Det brandpåverkade landskapet och dess dynamik skapar viktiga substrat och livsmiljöer för många pyrofila arter. På grund av att skogsbränderna har minskat i antal sedan 1800-talet, har kontrollerade naturvårdsbränningar utförts som ett komplement för dessa sedan 1980-talet. De kontrollerade naturvårdsbränningarna skapar de miljöer och substrat som många arter är beroende av. Eftersom tidigare mänsklig verksamhet satt prägel på skogarna återfinns idag ett stort antal fornlämningar och övriga kulturhistoriska lämningar i skogsmarkerna. Det är en utmaning att utföra naturvårdsbränningarna så att dessa lämningar inte skadas. Det råder också en brist på tydliga riktlinjer om hur Länsstyrelserna ska förhålla sig till naturvårdsbränningar i områden med lämningar. Denna studies syfte var att undersöka vilken inställning Länsstyrelserna har till naturvårdsbränningar i områden med fornlämningar eller övriga kulturhistoriska lämningar.

    Nyckelord: Naturvårdsbränningar, fornlämningar, övriga kulturhistoriska lämningar, Länsstyrelsen

    Keyword: Prescribed burnings, ancient remains, other cultural-historical remains, County Administrative Boards

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  • 28. Adam, B.
    et al.
    Klawonn, I.
    Svedén, J.
    Bergkvist, J.
    Nahar, N.
    Walve, J.
    Littmann, S.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Department of Geology.
    Lavik, G.
    Kuypers, M.M.M.
    Ploug, H.
    N2-fixation, ammonium release, and N-transfer to the microbial and classical food web within a plankton community.2016In: The ISME Journal, ISSN 1751-7362, E-ISSN 1751-7370, Vol. 19, p. 450-459Article in journal (Refereed)
    Abstract [en]

    We investigated the role of N2-fixation by the colony-forming cyanobacterium, Aphanizomenon spp., for the plankton community and N-budget of the N-limited Baltic Sea during summer by using stable isotope tracers combined with novel secondary ion mass spectrometry, conventional mass spectrometry and nutrient analysis. When incubated with 15N2, Aphanizomenon spp. showed a strong 15N-enrichment implying substantial 15N2-fixation. Intriguingly, Aphanizomenon did not assimilate tracers of 15NH4+ from the surrounding water. These findings are in line with model calculations that confirmed a negligible N-source by diffusion-limited NH4+ fluxes to Aphanizomenon colonies at low bulk concentrations (<250 nm) as compared with N2-fixation within colonies. No N2-fixation was detected in autotrophic microorganisms <5 μm, which relied on NH4+ uptake from the surrounding water. Aphanizomenon released about 50% of its newly fixed N2 as NH4+. However, NH4+ did not accumulate in the water but was transferred to heterotrophic and autotrophic microorganisms as well as to diatoms (Chaetoceros sp.) and copepods with a turnover time of ~5 h. We provide direct quantitative evidence that colony-forming Aphanizomenon releases about half of its recently fixed N2 as NH4+, which is transferred to the prokaryotic and eukaryotic plankton forming the basis of the food web in the plankton community. Transfer of newly fixed nitrogen to diatoms and copepods furthermore implies a fast export to shallow sediments via fast-sinking fecal pellets and aggregates. Hence, N2-fixing colony-forming cyanobacteria can have profound impact on ecosystem productivity and biogeochemical processes at shorter time scales (hours to days) than previously thought.

  • 29.
    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.

  • 30.
    Adams, Susan B.
    et al.
    US Forest Serv, USDA, Southern Res Stn, Ctr Bottomland Hardwoods Res, 1000 Front St, Oxford, MS 38655 USA..
    Hereford, Scott G.
    US Fish & Wildlife Serv, Mississippi Sandhill Crane Natl Wildlife Refuge, 7200 Crane Lane, Gautier, MS 39553 USA..
    Hyseni, Chaz
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Animal ecology.
    Burrow Densities of Primary Burrowing Crayfishes in Relation to Prescribed Fire and Mechanical Vegetation Treatments2021In: Water, E-ISSN 2073-4441, Vol. 13, no 13, article id 1854Article in journal (Refereed)
    Abstract [en]

    Fire suppression and other factors have drastically reduced wet prairie and pine savanna ecosystems on the Coastal Plain of the southeastern United States. Restoration of these open-canopy environments often targets one or several charismatic species, and semi-aquatic species such as burrowing crayfishes are often overlooked in these essentially terrestrial environments. We examined the relationship between primary burrowing crayfishes and three vegetation treatments implemented over at least the past two decades in the Mississippi Sandhill Crane National Wildlife Refuge. Vegetation in the 12 study sites had been frequently burned, frequently mechanically treated, or infrequently managed. Creaserinus spp., primarily C. oryktes, dominated the crayfish assemblage in every site. We counted crayfish burrow openings and coarsely categorized vegetation characteristics in 90, 0.56-m(2) quadrats evenly distributed among six transects per site. The number of active burrow openings was negatively, exponentially related to both the percent cover of woody vegetation and the maximum height of woody vegetation in quadrats, and to the number of trees taller than 1.2 m per transect, indicating that woody plant encroachment was detrimental to the crayfishes. Results were consistent with several other studies from the eastern US, indicating that some primary burrowing crayfishes are habitat specialists adapted to open-canopy ecosystems.

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  • 31. Adeleke, Rasheed
    et al.
    Bello-Akinosho, Maryam
    Maila, Mphekgo
    Lee, Natuschka
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences. Lehrstuhl für Mikrobiologie, Technische Universität München.
    Roles of extremophiles in bioremediation of polycyclic aromatic hydrocarbon contaminated soil environment2020In: Biotechnological applications of extremophilic microorganisms / [ed] Natuschka M. Lee, Walter de Gruyter, 2020, p. 197-230Chapter in book (Refereed)
  • 32.
    Adolfsson, Oscar
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Consequences on population dynamics following regained connectivity in pike (Esox lucius) spawning location2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Distributional movements of subpopulations may act as a buffer to prevent the loss of a species in a certain area. However, within subpopulations adaptations may evolve that makes the inhabitants of a certain habitat to better cope with prevailing environmental conditions. If such traits are related to reproduction, they may reduce the opportunity of gene exchange between other subpopulations. Also, a lack of adaptations to a specific habitat may be what prevents a group of individuals, arriving from an adjacent habitat, to successfully colonize an area where a previous subpopulation has been lost.This is the report from a field study conducted in the wetland Lake Långsjön, that in 2018 was restored in order to promote the recruitment of anadromous pike (Esox lucius) to the Baltic Sea. Commonly, wetlands that are restored to promote anadromous pike recruitment, are constructed so that they enable spawning migration from the sea towards the wetland and juvenile emigration towards the sea only. In that sense Lake Långsjön is different, from other wetlands restored for the same purpose, due to that it is connected to both the Baltic Sea and an upstream located freshwater lake. By quantifying the migration of pike (spawners and juveniles) in both directions I explore the consequences that the regained connectivity between the Lake Långsjön and the coast may have on the population dynamics within this wetland; (i) whether it is potentially influenced by allowing mixture between pike with different migratory strategies for spawning (anadromous and potamodromous), (ii) what drivers there are of pike fry emigration and how they may influence the pike fry emigration route and (iii) whether or not the pike of potamodromous origin, resident in the upstream located lake, may work as a source, providing the Baltic Sea with pike juveniles. Pike spawners arriving in the wetland were caught in traps between March - April. Pike fry were caught withing the wetland with fyke nets and by netting. Emigrating pike fry were caught in fyke nets. Findings suggest that spawning migration patterns do not differ between anadromous and potamodromous pike. However, the spawners arriving from the Baltic Sea I suggested are to be composed by offspring of potamodromous origin, possibly hatched during the previous season, and that they as juveniles swam downstream. This, in turn, indicates that the potamodromous stock can help establish an anadromous stock in the Baltic Sea. Still, due to the observation of pike fry displaying an emigration behaviour upstream, origin is identified as a factor that may influence the pike fry emigration route. Also, this emigration pattern seems to indicate a heritable trait that has not been described before among pike, that of downstream spawning. The restoration of the wetland and the regained connectivity is key, both for the ability to restock the Baltic Sea with pike juveniles but also to ensure the conservation of a fascinating stock of pike exhibiting a unique spawning strategy

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  • 33.
    Adolfsson, Oscar
    Karlstad University, Faculty of Health, Science and Technology (starting 2013).
    Effekter av inkuberingstemperatur hos juvenil atlantlax (Salmo salar L.)2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Rising temperatures, because of climate change, will have major consequences for the world's fish populations, including the Atlantic salmon Salmo salar L. The greatest temperature changes are expected to occur during winter, which will affect S. salar since the eggs are developing during this time of year. Several studies have shown that elevated temperatures during embryogenesis cause morphological changes, in S. Salar, that are shown in later life stages. Some of these studies indicate that eggs incubated at high temperatures should generate parr with deeper bodies. To investigate whether high temperatures during the egg stage cause changes in body shape, parr from normal and high temperature incubated eggs, referred to as as “cold” and “warm” fish, respectively, were examined. A box-truss of euclidean distances between 10 landmarks on the fish body and a discriminant function analysis (DFA) was used to determine which of the distances best discriminated between the two groups. The test showed a significant discrimination between cold and warm parr regarding body shape where cold parr had greater heads and warm parr were deeper over the tail region and showed greater distances between the pelvic fin and the front attachment of the anal fin. 67,3 % of all parr where correctly classified by the test. These results support those notions that indicates that the incubation temperature is important for the morphological development of S. salar although it does not support the hypothesis.

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  • 34.
    Aeppli, Christoph
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Bastviken, David
    Andersson, Per
    Gustafsson, Örjan
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Chlorine Isotope Effects and Composition of Naturally Produced Organochlorines from Chloroperoxidases, Flavin-Dependent Halogenases, and in Forest Soil2013In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 47, no 13, p. 6864-6871Article in journal (Refereed)
    Abstract [en]

    The use of stable chlorine isotopic signatures (delta Cl-37) of organochlorine compounds has been suggested as a tool to determine both their origins and transformations in the environment. Here we investigated the delta Cl-37 fractionation of two important pathways for enzymatic natural halogenation: chlorination by chloroperoxidase (CPO) and flavin-dependent halogenases (FDH). Phenolic products of CPO were highly Cl-37 depleted (delta Cl-37 = -12.6 +/- 0.9 parts per thousand); significantly more depleted than all known industrially produced organochlorine compounds (delta Cl-37 = -7 to +6 parts per thousand). In contrast, four FDH products did not exhibit any observable isotopic shifts (delta Cl-37 = -0.3 +/- 0.6 parts per thousand). We attributed the different isotopic effect to the distinctly different chlorination mechanisms employed by the two enzymes. Furthermore, the delta Cl-37 in bulk organochlorines extracted from boreal forest soils were only slightly depleted in Cl-37 relative to inorganic Cl. In contrast to previous suggestions that CPO plays a key role in production of soil organochlorines, this observation points to the additional involvement of either other chlorination pathways, or that dechlorination of naturally produced organochlorines can neutralize delta Cl-37 shifts caused by CPO chlorination. Overall, this study demonstrates that chlorine isotopic signatures are highly useful to understand sources and cycling of organochlorines in nature. Furthermore, this study presents delta Cl-37 values of FDH products as well of bulk organochlorines extracted from pristine forest soil for the first time.

  • 35.
    Aeppli, Christoph
    et al.
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Tysklind, Mats
    Holmstrand, Henry
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Gustafsson, Örjan
    Stockholm University, Faculty of Science, Department of Applied Environmental Science (ITM).
    Use of Cl and C Isotopic Fractionation to Identify Degradation and Sources of Polychlorinated Phenols: Mechanistic Study and Field Application2013In: Environmental Science and Technology, ISSN 0013-936X, E-ISSN 1520-5851, Vol. 47, no 2, p. 790-797Article in journal (Refereed)
    Abstract [en]

    The widespread use of chlorinated phenols (CPs) as a wood preservative has led to numerous contaminated sawmill sites. However, it remains challenging to assess the extent of in situ degradation of CPs. We evaluated the use of compound-specific chlorine and carbon isotope analysis (Cl- and C-CSLA) to assess CP biotransformation. In a laboratory system, we measured isotopic fractionation during oxidative 2,4,6-trichlorophenol dechlorination by representative soil enzymes (C. fumago chloroperoxidase, horseradish peroxidase, and laccase from T. versicolor). Using a mathematical model, the validity of the Rayleigh approach to evaluate apparent kinetic isotope effects (AKIE) was confirmed. A small but significant Cl-AKIE of 1.0022 +/- 0.0006 was observed for all three enzymes, consistent with a reaction pathway via a cationic radical species. For carbon, a slight inverse isotope effect was observed (C-AKIE = 0.9945 +/- 0.0019). This fractionation behavior is clearly distinguishable from reported reductive dechlorination mechanisms. Based on these results we then assessed degradation and apportioned different types of technical CP mixtures used at two former sawmill sites. To our knowledge, this is the first study that makes use of two-element CSIA to study sources and transformation of CPs in the environment.

  • 36. Aerts, R.
    et al.
    Callaghan, T. V.
    Dorrepaal, E.
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences. Systems Ecology, Department of Ecological Science, VU University Amsterdam, Amsterdam, The Netherlands.
    van Logtestijn, R. S. P.
    Cornelissen, J. H. C.
    Seasonal climate manipulations have only minor effects on litter decomposition rates and N dynamics but strong effects on litter P dynamics of sub-arctic bog species2012In: Oecologia, ISSN 0029-8549, E-ISSN 1432-1939, Vol. 170, no 3, p. 809-819Article in journal (Refereed)
    Abstract [en]

    Litter decomposition and nutrient mineralization in high-latitude peatlands are constrained by low temperatures. So far, little is known about the effects of seasonal components of climate change (higher spring and summer temperatures, more snow which leads to higher winter soil temperatures) on these processes. In a 4-year field experiment, we manipulated these seasonal components in a sub-arctic bog and studied the effects on the decomposition and N and P dynamics of leaf litter of Calamagrostis lapponica, Betula nana, and Rubus chamaemorus, incubated both in a common ambient environment and in the treatment plots. Mass loss in the controls increased in the order Calamagrostis < Betula < Rubus. After 4 years, overall mass loss in the climate-treatment plots was 10 % higher compared to the ambient incubation environment. Litter chemistry showed within each incubation environment only a few and species-specific responses. Compared to the interspecific differences, they resulted in only moderate climate treatment effects on mass loss and these differed among seasons and species. Neither N nor P mineralization in the litter were affected by the incubation environment. Remarkably, for all species, no net N mineralization had occurred in any of the treatments during 4 years. Species differed in P-release patterns, and summer warming strongly stimulated P release for all species. Thus, moderate changes in summer temperatures and/or winter snow addition have limited effects on litter decomposition rates and N dynamics, but summer warming does stimulate litter P release. As a result, N-limitation of plant growth in this sub-arctic bog may be sustained or even further promoted.

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  • 37.
    Affonso, Igor de Paiva
    et al.
    Universidade Estadual de Maringá, Maringá, Brazil; Universidade Tecnológica Federal do Paraná, Campus Ponta Grossa, Brazil.
    Karling, Leticia Cucolo
    Universidade Estadual de Maringá, Maringá, Brazil.
    Takemoto, Ricardo Massato
    Núcleo de Pesquisas em Limnologia Ictiologia e Aqüicultura – Nupélia, Maringá, Brazil.
    Gomes, Luiz Carlos
    Universidade Estadual de Maringá, Maringá, Brazil; Núcleo de Pesquisas em Limnologia Ictiologia e Aqüicultura – Nupélia, Maringá, Brazil.
    Nilsson, Per Anders
    Karlstad University, Faculty of Health, Science and Technology (starting 2013), Department of Environmental and Life Sciences (from 2013). Department of Biology, Lund University, Lund, Sweden.
    Light-induced eye-fluke behavior enhances parasite life cycle2017In: Frontiers in Ecology and the Environment, ISSN 1540-9295, E-ISSN 1540-9309, Vol. 15, no 6, p. 340-341Article in journal (Refereed)
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  • 38.
    Agborg, Maja
    et al.
    Malmö University, Faculty of Education and Society (LS).
    Berggren, Maria
    Malmö University, Faculty of Education and Society (LS).
    Slå upp dörrarna för utomhuspedagogik: En kunskapsöversikt om utomhuspedagogikens lärandemöjligheter2021Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Denna kunskapsöversikt inriktar sig på utomhuspedagogik och syftar till att reda ut vilken inverkan utomhuspedagogik har på elevers lärande och inställning till naturorienterande ämnen. Den undersöker även om utomhuspedagogik bidrar till ökad förståelse för hållbar utveckling. Kunskapsöversikten undersöker både elevers och lärares attityd samt kunskapsinhämtningen med utomhusundervisningen. 12 vetenskapliga artiklar ligger till grund för arbetet. Artiklarna har tagits fram genom en noggrann urvalsprocess och granskats utförligt. Resultatet visar på att utomhuspedagogik har en positiv inverkan på elevers inlärning och inställning till naturorienterade ämnen. Däremot finns varierande resultat när det kommer till ökad förståelse för hållbar utveckling. Utomhusundervisning kan bidra till en känsla av samhörighet till naturen men behöver inte nödvändigtvis innebära en ökad förståelse för begreppet hållbar utveckling.

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  • 39.
    Agerstrand, Marlene
    et al.
    KTH, School of Architecture and the Built Environment (ABE), Philosophy and History of Technology, Philosophy.
    Kuester, A.
    Bachmann, J.
    Breitholtz, M.
    Ebert, I.
    Rechenberg, B.
    Ruden, Christina
    KTH, School of Architecture and the Built Environment (ABE), Philosophy and History of Technology, Philosophy.
    Reporting and evaluation criteria as means towards a transparent use of ecotoxicity data for environmental risk assessment of pharmaceuticals2011In: Environmental Pollution, ISSN 0269-7491, E-ISSN 1873-6424, Vol. 159, no 10, p. 2487-2492Article in journal (Refereed)
    Abstract [en]

    Ecotoxicity data with high reliability and relevance are needed to guarantee the scientific quality of environmental risk assessments of pharmaceuticals. The main advantages of a more structured approach to data evaluation include increased transparency and predictability of the risk assessment process, and the possibility to use non-standard data. In this collaboration, between the research project MistraPharma and the German Federal Environment Agency, a new set of reporting and evaluation criteria is presented and discussed. The new criteria are based on the approaches in the literature and the OECD reporting requirements, and have been further developed to include both reliability and relevance of test data. Intended users are risk assessors and researchers performing ecotoxicological experiments, but the criteria can also be used for education purposes and in the peer-review process for scientific papers. This approach intends to bridge the gap between the regulator and the scientist's needs and way of work.

  • 40.
    Agestam, Elin
    Karlstad University.
    Spridning av contorta från bestånd i södra Sverige: En fältstudie i Östergötland och Småland2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Contorta (Pinus contorta) is a coniferous tree species from western North America that has been introduced mainly in northern Sweden. The purpose of this work was to evaluate how far and to what extent (number of self-dispersal seedlings/ha) Contorta has spread from older populations in southern Sweden. The result can be used in assessing the risk of spreading in southern Sweden. The three forest stands used for this work were located in southern Östergötland and northern Småland, Sweden. The data collection was done in three stages in each stand: 1. Assessment if contorta can be disseminated and established from stocks in southern Sweden. 2. Subjective inventory of Contorta plants in selected areas. 3. Quantitative inventory of contorta plants along defined corridors, 2 meters wide and 250 meters long, in four directions from the edge of the stock. In the inventory of subjectively selected areas, contorta plants were found 350 meters from a contorta stand and in the objective inventory 50 meters from a contorta stand. A total of 27 contorta plants (equivalent to 450 plants/ha) was found in subjectively inventory and 18 contorta plants (45 plants/ha) were found in the quantitative inventory. All Contorta seedlings were found on disturbed ground and where the canopy cover of trees was zero, i.e. where the access to light was highest. On the other hand, based on this study, it is not possible to say which factor is most important for the establishment, field disturbance or light supply.

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  • 41.
    Agić, Heda
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    A new species of small acritarch with porous wall structure from the early Cambrian of Estonia, and implications for the fossil record of eukaryotic picoplankton2016In: Palynology, ISSN 0191-6122, E-ISSN 1558-9188, Vol. 40, no 3, p. 343-356Article in journal (Refereed)
    Abstract [en]

    The Proterozoic-Phanerozoic transition records a general trend of decrease in phytoplankton cell size, in contrast tothe earlier and much larger Ediacaran acritarchs. Particularly minute, unornamented but sculptured organic-walledmicrofossils have been recovered from the lower Cambrian Lükati Formation in northern Estonia. The lack of anysignificant thermal alteration in the formation allowed for excellent preservation of fine microstructures on thesemicrofossils. Among the rich palynomorph assemblage in Lükati, a new species of tiny, spheroidal eukaryoticmicrofossil is recorded: Reticella corrugata gen. et sp. nov. It is characterised by a corrugated and flexible vesicle wallthat is densely perforated by nano-scale pores. Despite its unique morphology, the new species shares diagnosticcharacters with fossil and extant prasinophyte algae. R. corrugata is among the smallest microfossils with typicaleukaryotic morphology (conspicuous wall sculpture) and contributes to the diversity of the size class of smallacritarchs. Size, abundance, inferred prasinophyte affinity and eukaryotic wall sculpture make this new taxon alikely member of the early eukaryotic picoplankton.

  • 42.
    Agnas, Axel Jönses Bernard
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Biology Education Centre.
    Non-Independent Mate Choice in Female Humans (Homo sapiens): Progression to the Field 2016Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    There is much evidence that mate-choice decisions made by humans are affected by social/contextual information. Women seem to rate men portrayed in a relationship as more desirable than the same men when portrayed as single. Laboratory studies have found evidence suggesting that human mate choice, as in other species, is dependent on the mate choice decisions made by same-sex rivals. Even though non-independent mate choice is an established and well-studied area of mate choice, very few field studies have been performed. This project aims to test whether women’s evaluation of potential mates desirability is dependent/non-independent of same-sex rivals giving the potential mates sexual interest. This is the first field study performed in a modern human’s natural habitat aiming to test for non- independent mate choice in humans.

    No desirability enhancement effect was found. The possibilities that earlier studies have found an effect that is only present in laboratory environments or have measured effects other than non-independent mate choice are discussed. I find differences in experimental design to be the most likely reason why the present study failed to detect the effect found in previous studies. This field study, the first of its sort, has generated important knowledge for future experimenters, where the most important conclusion is that major limitations in humans ability to register and remember there surrounding should be taken in consideration when designing any field study investigating human mate choice. 

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  • 43.
    Agostinelli, Marta
    et al.
    Swedish University of Agricultural Sciences, Sweden.
    Cleary, Michelle
    Swedish University of Agricultural Sciences, Sweden.
    Martín, Juan A
    Technical University of Madrid, Spain.
    Albrectsen, Benedicte R
    Umeå University, Sweden.
    Witzell, Johanna
    Swedish University of Agricultural Sciences, Sweden.
    Pedunculate Oaks (Quercus robur L.) Differing in Vitality as Reservoirs for Fungal Biodiversity2018In: Frontiers in Microbiology, E-ISSN 1664-302X, Vol. 9, article id 1758Article in journal (Refereed)
    Abstract [en]

    Ecological significance of trees growing in urban and peri-urban settings is likely to increase in future land-use regimes, calling for better understanding of their role as potential reservoirs or stepping stones for associated biodiversity. We studied the diversity of fungal endophytes in woody tissues of asymptomatic even aged pedunculate oak trees, growing as amenity trees in a peri-urban setting. The trees were classified into three groups according to their phenotypic vitality (high, medium, and low). Endophytes were cultured on potato dextrose media from surface sterilized twigs and DNA sequencing was performed to reveal the taxonomic identity of the morphotypes. In xylem tissues, the frequency and diversity of endophytes was highest in oak trees showing reduced vitality. This difference was not found for bark samples, in which the endophyte infections were more frequent and communities more diverse than in xylem. In general, most taxa were shared across the samples with few morphotypes being recovered in unique samples. Leaf phenolic profiles were found to accurately classify the trees according to their phenotypic vitality. Our results confirm that xylem is more selective substrate for endophytes than bark and that endophyte assemblages in xylem are correlated to the degree of host vitality. Thus, high vitality of trees may be associated with reduced habitat quality to wood-associated endophytes.

  • 44. Aguiar, Francisca C.
    et al.
    Segurado, Pedro
    Martins, Maria Joao
    Bejarano, Maria Dolores
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Nilsson, Christer
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences.
    Portela, Maria Manuela
    Merritt, David M.
    The abundance and distribution of guilds of riparian woody plants change in response to land use and flow regulation2018In: Journal of Applied Ecology, ISSN 0021-8901, E-ISSN 1365-2664, Vol. 55, no 5, p. 2227-2240Article in journal (Refereed)
    Abstract [en]

    1. Many riparian ecosystems in Mediterranean Europe are affected by land use and flow alteration by dams. We focused on understanding how these stressors and their components affect riparian forests in the region. We asked the following questions: (1) Are there well‐defined, responsive riparian guilds? (2) Do dam‐induced streamflows determine abundance and distribution of riparian guilds? (3) What are the main drivers governing composition and cover of riparian guilds in regulated rivers?

    2. We inventoried the cover of riparian woody species in free‐flowing rivers and downstream of dams. We performed a cluster analysis and ordination to derive riparian guilds, using abundance data from 66 riparian woody species and 26 functional plant traits. We used a reduced set of principal components for the environment, land use and hydrology, and general linear modelling to explore the effect of these factors (separately and combined) on riparian guilds.

    3. We found that: (1) four dominant guilds are responsive to disturbance in southwestern European streams, namely the obligate riparian, water‐stress tolerant, deciduous competitive and Mediterranean evergreen guilds; (2) a set of land use and hydrological variables differentially affect the diverse co‐occurring riparian guilds; (3) frequency and duration of high flow pulses and the low‐flow conditions were major drivers of change in landscapes dominated by intensive agriculture and forestry; (4) storage reservoirs reduced the cover of obligate riparian and Mediterranean evergreen guilds, and increased the abundance of water‐stress tolerant and deciduous competitive guilds, while run‐of‐river dams, having limited water storage, reduced both obligate and deciduous competitive guilds.

    4. Synthesis and applications. Future research in southwestern Europe should address the resilience of riparian guilds and the effects of interacting landscape factors and stressors on guild distribution. Streamflow regulations downstream of reservoirs should focus on specific flow components, namely the magnitude of flows, and frequency and duration of extreme flow events. For successful mitigation of the dam‐induced effects on riparian vegetation, river management plans must incorporate the environmental and land use site‐specific contexts.

  • 45.
    Aguilera, Anabella
    et al.
    Department of Biology and Environmental Science, Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Kalmar, Sweden.
    Alegria Zufia, Javier
    Department of Biology and Environmental Science, Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Kalmar, Sweden.
    Bas Conn, Laura
    Department of Biology and Environmental Science, Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Kalmar, Sweden.
    Gurlit, Leandra
    Department of Biology and Environmental Science, Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Kalmar, Sweden.
    Śliwińska-Wilczewska, Sylwia
    Mount Allison University, Sackville, New Brunswick, Canada; Laboratory of Marine Plant Ecophysiology, Institute of Oceanography, University of Gdansk, Gdynia, Poland.
    Budzałek, Gracjana
    Laboratory of Marine Plant Ecophysiology, Institute of Oceanography, University of Gdansk, Gdynia, Poland.
    Lundin, Daniel
    Department of Biology and Environmental Science, Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Kalmar, Sweden.
    Pinhassi, Jarone
    Department of Biology and Environmental Science, Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Kalmar, Sweden.
    Legrand, Catherine
    Department of Biology and Environmental Science, Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Kalmar, Sweden; School of Business, Innovation and Sustainability, Halmstad University, Halmstad, Sweden.
    Farnelid, Hanna
    Department of Biology and Environmental Science, Centre for Ecology and Evolution in Microbial Model Systems (EEMiS), Linnaeus University, Kalmar, Sweden.
    Ecophysiological analysis reveals distinct environmental preferences in closely related Baltic Sea picocyanobacteria2023In: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920Article in journal (Refereed)
    Abstract [en]

    Cluster 5 picocyanobacteria significantly contribute to primary productivity in aquatic ecosystems. Estuarine populations are highly diverse and consist of many co-occurring strains, but their physiology remains largely understudied. In this study, we characterized 17 novel estuarine picocyanobacterial strains. Phylogenetic analysis of the 16S rRNA and pigment genes (cpcB and cpeBA) uncovered multiple estuarine and freshwater-related clusters and pigment types. Assays with five representative strains (three phycocyanin rich and two phycoerythrin rich) under temperature (10–30°C), light (10–190 μmol photons m−2 s−1), and salinity (2–14 PSU) gradients revealed distinct growth optima and tolerance, indicating that genetic variability was accompanied by physiological diversity. Adaptability to environmental conditions was associated with differential pigment content and photosynthetic performance. Amplicon sequence variants at a coastal and an offshore station linked population dynamics with phylogenetic clusters, supporting that strains isolated in this study represent key ecotypes within the Baltic Sea picocyanobacterial community. The functional diversity found within strains with the same pigment type suggests that understanding estuarine picocyanobacterial ecology requires analysis beyond the phycocyanin and phycoerythrin divide. This new knowledge of the environmental preferences in estuarine picocyanobacteria is important for understanding and evaluating productivity in current and future ecosystems.

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  • 46.
    Aguilera, Anabella
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Alegria Zufia, Javier
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Bas Conn, Laura
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Gurlit, Leandra
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Śliwińska‐Wilczewska, Sylwia
    Mount Allison University, Canada;University of Gdansk, Poland.
    Budzałek, Gracjana
    University of Gdansk, Poland.
    Lundin, Daniel
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Pinhassi, Jarone
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Legrand, Catherine
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. Halmstad University, Sweden.
    Farnelid, Hanna
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Ecophysiological analysis reveals distinct environmental preferences in closely related Baltic Sea picocyanobacteria2023In: Environmental Microbiology, ISSN 1462-2912, E-ISSN 1462-2920, Vol. 25, no 9, p. 1674-1695Article in journal (Refereed)
    Abstract [en]

    Cluster 5 picocyanobacteria significantly contribute to primary productivity in aquatic ecosystems. Estuarine populations are highly diverse and consist of many co-occurring strains, but their physiology remains largely understudied. In this study, we characterized 17 novel estuarine picocyanobacterial strains. Phylogenetic analysis of the 16S rRNA and pigment genes (cpcBandcpeBA) uncovered multiple estuarine and freshwater-related clusters and pigment types. Assays with five representative strains (three phycocyanin rich and two phycoerythrin rich) under temperature (10–30°C), light(10–190 μmol  photons  m-2s-1), and salinity (2–14  PSU) gradients revealed distinct growth optima and tolerance, indicating that genetic variability was accompanied by physiological diversity. Adaptability to environmental conditions was associated with differential pigment content and photosynthetic performance. Amplicon sequence variants at a coastal and an offshore station linked population dynamics with phylogenetic clusters, supporting that strains isolated in this study represent key ecotypes within the Baltic Sea picocyanobacterial community. The functional diversity found within strains with the same pigment type suggests that understanding estuarine picocyanobacterial ecology requires analysis beyond the phycocyanin and phycoerythrin divide. This new knowledge of the environmental preferences in estuarine picocyanobacteria is important for understanding and evaluating productivity in current and future ecosystems.

  • 47.
    Aguilera, Anabella
    et al.
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science.
    Almanza, Viviana
    Univ Concepcion, Chile.
    Haakonsson, Signe
    Univ Republica, Uruguay.
    Palacio, Hilda
    Univ CES, Colombia.
    Rodas, Gilberto A. Benitez
    Univ Nacl Asuncion, Paraguay.
    Barros, Mario U. G.
    Univ Fed Ceara, Brazil;Water Resources Management Co Ceara, Brazil.
    Capelo-Neto, Jose
    Univ Fed Ceara, Brazil.
    Urrutia, Roberto
    Univ Concepcion, Chile.
    Aubriot, Luis
    Univ Republica, Uruguay.
    Bonilla, Sylvia
    Univ Republica, Uruguay.
    Cyanobacterial bloom monitoring and assessment in Latin America2023In: Harmful Algae, ISSN 1568-9883, E-ISSN 1878-1470, Vol. 125, article id 102429Article in journal (Refereed)
    Abstract [en]

    Cyanobacterial blooms have serious adverse effects on human and environmental health. In Latin America, one of the main world's freshwater reserves, information on this phenomenon remains sparse. To assess the current situation, we gathered reports of cyanobacterial blooms and associated cyanotoxins in freshwater bodies from South America and the Caribbean (Latitude 22 degrees N to 45 degrees S) and compiled the regulation and monitoring procedures implemented in each country. As the operational definition of what is a cyanobacterial bloom remains controversial, we also analyzed the criteria used to determine the phenomena in the region. From 2000 to 2019, blooms were reported in 295 water bodies distributed in 14 countries, including shallow and deep lakes, reservoirs, and rivers. Cyanotoxins were found in nine countries and high concentrations of microcystins were reported in all types of water bodies. Blooms were defined according to different, and sometimes arbitrary criteria including qualitative (changes in water color, scum presence), quantitative (abundance), or both. We found 13 different cell abundance thresholds defining bloom events, from 2 x 10(3) to 1 x 10(7) cells mL(-1). The use of different criteria hampers the estimation of bloom occurrence, and consequently the associated risks and economic impacts. The large differences between countries in terms of number of studies, monitoring efforts, public access to the data and regulations regarding cyanobacteria and cyanotoxins highlights the need to rethink cyanobacterial bloom monitoring, seeking common criteria. General policies leading to solid frameworks based on defined criteria are needed to improve the assessment of cyanobacterial blooms in Latin America. This review represents a starting point toward common approaches for cyanobacterial monitoring and risk assessment, needed to improve regional environmental policies.

  • 48.
    Aguirre-Gutierrez, Jesus
    et al.
    Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford, England.;Naturalis Biodivers Ctr, Biodivers Dynam, Leiden, Netherlands..
    Malhi, Yadvinder
    Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford, England..
    Lewis, Simon L.
    Univ Leeds, Sch Geog, Ecol & Global Change, Leeds, W Yorkshire, England.;UCL, Dept Geog, London, England..
    Fauset, Sophie
    Univ Plymouth, Sch Geog Earth & Environm Sci, Plymouth, Devon, England..
    Adu-Bredu, Stephen
    KNUST, CSIR Forestry Res Inst Ghana, Univ Post Off, Kumasi, Ghana..
    Affum-Baffoe, Kofi
    Forestry Commiss Ghana, Mensurat Unit, Kumasi, Ghana..
    Baker, Timothy R.
    Univ Leeds, Sch Geog, Ecol & Global Change, Leeds, W Yorkshire, England..
    Gvozdevaite, Agne
    Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford, England..
    Hubau, Wannes
    Univ Leeds, Sch Geog, Ecol & Global Change, Leeds, W Yorkshire, England.;Royal Museum Cent Africa, Serv Wood Biol, Tervuren, Belgium..
    Moore, Sam
    Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford, England..
    Peprah, Theresa
    KNUST, CSIR Forestry Res Inst Ghana, Univ Post Off, Kumasi, Ghana..
    Zieminska, Kasia
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Ecology and Genetics, Plant Ecology and Evolution. Arnold Arboretum Harvard Univ, Boston, MA 02115 USA..
    Phillips, Oliver L.
    Univ Leeds, Sch Geog, Ecol & Global Change, Leeds, W Yorkshire, England..
    Oliveras, Imma
    Univ Oxford, Environm Change Inst, Sch Geog & Environm, Oxford, England..
    Long-term droughts may drive drier tropical forests towards increased functional, taxonomic and phylogenetic homogeneity2020In: Nature Communications, E-ISSN 2041-1723, Vol. 11, no 1Article in journal (Refereed)
    Abstract [en]

    Tropical ecosystems adapted to high water availability may be highly impacted by climatic changes that increase soil and atmospheric moisture deficits. Many tropical regions are experiencing significant changes in climatic conditions, which may induce strong shifts in taxonomic, functional and phylogenetic diversity of forest communities. However, it remains unclear if and to what extent tropical forests are shifting in these facets of diversity along climatic gradients in response to climate change. Here, we show that changes in climate affected all three facets of diversity in West Africa in recent decades. Taxonomic and functional diversity increased in wetter forests but tended to decrease in forests with drier climate. Phylogenetic diversity showed a large decrease along a wet-dry climatic gradient. Notably, we find that all three facets of diversity tended to be higher in wetter forests. Drier forests showed functional, taxonomic and phylogenetic homogenization. Understanding how different facets of diversity respond to a changing environment across climatic gradients is essential for effective long-term conservation of tropical forest ecosystems. Different aspects of biodiversity may not necessarily converge in their response to climate change. Here, the authors investigate 25-year shifts in taxonomic, functional and phylogenetic diversity of tropical forests along a spatial climate gradient in West Africa, showing that drier forests are less stable than wetter forests.

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  • 49.
    Aguirre-Gutierrez, Jesus
    et al.
    Naturalis Biodivers Ctr, Netherlands;Univ Oxford, UK;Univ Amsterdam, Netherlands.
    WallisDeVries, Michiel F.
    De Vlinderstichting, Netherlands;Wageningen Univ, Netherlands.
    Marshall, Leon
    Naturalis Biodivers Ctr, Netherlands;Univ Namur, Belgium.
    van't Zelfde, Maarten
    Naturalis Biodivers Ctr, Netherlands;Leiden Univ, Netherlands.
    Villalobos-Arambula, Alma R.
    Univ Guadalajara, Mexico.
    Boekelo, Bastiaen
    Wageningen Univ & Res, Netherlands.
    Bartholomeus, Harm
    Wageningen Univ & Res, Netherlands.
    Franzén, Markus
    Linnaeus University, Faculty of Health and Life Sciences, Department of Biology and Environmental Science. UFZ, Helmholtz Ctr Environm Res, Germany.
    Biesmeijer, Jacobus C.
    Naturalis Biodivers Ctr, Netherlands;Leiden Univ, Netherlands.
    Butterflies show different functional and species diversity in relationship to vegetation structure and land use2017In: Global Ecology and Biogeography, ISSN 1466-822X, E-ISSN 1466-8238, Vol. 26, no 10, p. 1126-1137Article in journal (Refereed)
    Abstract [en]

    AimBiodiversity is rapidly disappearing at local and global scales also affecting the functional diversity of ecosystems. We aimed to assess whether functional diversity was correlated with species diversity and whether both were affected by similar land use and vegetation structure drivers. Better understanding of these relationships will allow us to improve our predictions regarding the effects of future changes in land use on ecosystem functions and services. LocationThe Netherlands. MethodsWe compiled a dataset of c.3 million observations of 66 out of 106 known Dutch butterfly species collected across 6,075 sampling locations during a period of 7 years, together with very high-resolution maps of land use and countrywide vegetation structure data. Using a mixed-effects modelling framework, we investigated the relationship between functional and species diversity and their main land use and vegetation structure drivers. ResultsWe found that high species diversity does not translate into high functional diversity, as shown by their different spatial distribution patterns in the landscape. Functional and species diversity are mainly driven by different sets of structural and land use parameters (especially average vegetation height, amount of vegetation between 0.5 and 2m, natural grassland, sandy soils vegetation, marsh vegetation and urban areas). We showed that it is a combination of both vegetation structural characteristics and land use variables that defines functional and species diversity. Main conclusionsFunctional diversity and species diversity of butterflies are not consistently correlated and must therefore be treated separately. High functional diversity levels occurred even in areas with low species diversity. Thus, conservation actions may differ depending on whether the focus is on conservation of high functional diversity or high species diversity. A more integrative analysis of biodiversity at both species and trait levels is needed to infer the full effects of environmental change on ecosystem functioning.

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    Ah-King, Malin
    Uppsala University, Disciplinary Domain of Humanities and Social Sciences, Faculty of Arts, Centre for Gender Research.
    Flexible mate choice2010In: Encyclopedia of Animal Behavior / [ed] Janice Moore & Michael D. Breed, Elsevier , 2010Chapter in book (Other academic)
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