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  • 1.
    Abbaszadeh Shahri, Abbas
    et al.
    Department of Civil Engineering, Islamic Azad University, Roudehen Branch, Tehran, Iran Johan Lundberg AB, Uppsala, Sweden.
    Larsson, Stefan
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Soil and Rock Mechanics.
    Renkel, Crister
    Johan Lundberg AB, Uppsala, Sweden.
    Correction to: Artificial intelligence models to generate visualized bedrock level: a case study in Sweden (Modeling Earth Systems and Environment, (2020), 6, 3, (1509-1528), 10.1007/s40808-020-00767-0)2020In: Modeling Earth Systems and Environment, ISSN 2363-6203, E-ISSN 2363-6211, Vol. 6, no 4Article in journal (Refereed)
    Abstract [en]

    In the original version of this article, unfortunately a character of the Journal no in the reference 10 has been published incorrectly.

  • 2.
    Abdelmaksoud, Ahmed
    et al.
    Khalifa Univ Sci & Technol, Dept Earth Sci, Abu Dhabi, U Arab Emirates.;Assiut Univ, Dept Geol, Assiut, Egypt..
    Ali, Mohammed Y.
    Khalifa Univ Sci & Technol, Dept Earth Sci, Abu Dhabi, U Arab Emirates..
    Al Suwaidi, Aisha
    Khalifa Univ Sci & Technol, Dept Earth Sci, Abu Dhabi, U Arab Emirates..
    Koyi, Hemin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Khalifa Univ Sci & Technol, Dept Earth Sci, Abu Dhabi, U Arab Emirates..
    Petroleum system of the fold-and-thrust belt of the United Arab Emirates: New insights based on 1D and 2D basin modeling2023In: Marine and Petroleum Geology, ISSN 0264-8172, E-ISSN 1873-4073, Vol. 158, article id 106567Article in journal (Refereed)
    Abstract [en]

    The hydrocarbon potential of the fold-and-thrust belt (FTB) in the United Arab Emirates (UAE)-Oman mountains has received limited attention to date, leading to a poor understanding of the petroleum systems in this region. Despite the existence of hydrocarbon fields within the FTB, the source rock potential has not been adequately studied. This study aims to address this knowledge gap using 1D and 2D basin modeling approaches to evaluate the petroleum system of the FTB. In addition, gas chromatographs are also used to correlate hydrocarbon occurrences with their source rock. This study's findings identify the Silurian, Upper Cretaceous, Paleocene-Eocene, and Oligocene formations as the primary source rocks in the study area. Silurian shales, encountered in a well in the northern UAE, are currently considered overmature. The Cenozoic source rocks exhibit a spectrum of Total Organic Carbon (TOC) content, ranging from less than 1 to as high as 2 wt%, leading to variable degrees of expulsion efficiency. The maturity of these rocks varies based on their position in relation to the FTB and foredeep, with increasing maturity towards the north. The Upper Cretaceous sequences display low TOC and Hydrogen Index, indicating very low expulsion efficiency. The present-day distribution of maturity is largely influenced by Late Cretaceous and Oligocene-Miocene compressional events that affected the northern and northeastern Arabian Plate. This analysis shows that hydrocarbon expulsion from the Silurian source rocks was initiated during the Middle-Late Jurassic. These hydrocarbons are presumed to have migrated through Upper Permian, Jurassic, and Lower and middle Cretaceous reservoirs. Westward hydrocarbon migration, towards a regional bulge, may have also occurred following compressional events that resulted in lithospheric flexure and formation of the foreland basin. Notably, certain exceptions to migration towards the bulge include structural entrapment of hydrocarbons beneath the main frontal thrust zone of FTB and some structural traps beneath the Lower Fiqa Formation.

  • 3.
    Abdurahmanov, Fagan
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    BUILDING A SUSTAINABLE FUTURE WITH WIND ENERGY: AZERBAIJAN’S AMBITIOUS PLANS FOR KARABAKH2023Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Transitioning to renewable energy is critical for reaching global sustainable development goals. As an oil-rich country, Azerbaijan has recognized the need to develop its renewable energy sector. It has set ambitious goals for increasing the share of renewables in its energy mix and establishing a green energy zone in the Karabakh region. The purpose of this master's thesis is to assess the potential of wind energy in Azerbaijan's Karabakh region and surrounding areas and identify the best scenario for its development. Four scenarios were evaluated via the PROMETHEE II Multi-Criteria Decision Analysis (MCDA) method based on their economic, environmental, technological, and social factors. Interviews with real stakeholders were undertaken to elicit weights for the criteria, and a sensitivity analysis was conducted to evaluate the robustness of the results. The findings were shared with the stakeholders, and their input was integrated into the final analysis. According to the findings, Scenario 4, which includes more installed capacity and increased investment, is best suited for the growth of wind energy in the Karabakh and surrounding areas from the perspective of developer and governmental body. In contrast, renewable energy expert and the public prefer Scenario 1, with less land use and less capacity. The findings indicate that for the effective development of wind energy in the area, a balanced approach taking into account the opinions of all stakeholders, is essential. This study contributes to Azerbaijan's long-term development by offering valuable insights into the potential of wind energy in the Karabakh region and surrounding areas and supporting informed decision-making for its expansion.

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  • 4.
    Acikkol, Naz
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Testing the Cretaceous Diversity of Ichthyosaurs and Their Extinction Hypotheses Using a Quantitative Approach2015Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As portrayed in Before the Dinosaur: the Historical Significance of the Fossil Marine Reptiles, ichthyosaurs, as other Mesozoic marine amniotes, have been unfairly overshadowed by dinosaurs in both popular culture and the field of vertebrate palaeontology. Yet by the effort of dedicated researchers, work on these fish-like marine reptiles had never died out, and in fact a second wave of interest emerged in the late 20th century. Since then, research on ichthyosaurs has focused on discovery of new taxa, assessments of their palaeobiology, and quantitative analyses of their diversity. Despite ever-growing interests, patterns and mechanisms leading up to their extinction in the Cenomanian were insufficiently evaluated. In other words, hypotheses focusing on abrupt extinction linked to a crash in prey diversity, notably belemnites, over a catastrophic event at the end-Cenomanian remain poorly tested. The current project thus aims to test: 1) whether the Cretaceous diversity of ichthyosaurs reflects biological signals, and 2) correlation of their diversity with the diversity of Mesozoic cephalopods, such as belemnites and ammonites. In this regard, a species-level dataset of Cretaceous belemnites including belemnite-bearing formations was built to be employed together with the occurrence-based ichthyosaur and ammonite datasets in the same taxic level. Raw taxic counts, as observed diversities of the clades, were quantified in two different temporal scales, and compared with two sampling proxies. The model-based method was then applied to correct all taxic counts based on the two proxies in both time bins to acquire expected diversities of all the clades. Comparisons resulted in strong correlations between the clades’ observed diversities and proxies exposing biased patterns under the influence of sampling intensity. Whereas both observed and expected diversities show no evidence of a causal relationship between the predator and prey groups, suggesting that the latter’s diversity seems not being a parameter for the former’s, and thus being unsupportive for a prey-driven demise of the predator. Furthermore, the expected trend of ichthyosaurs indicates lower Albian diversity gradually declining towards their extinction in the Cenomanian, which appears to be contrasting with recent studies.

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    DegreeProject_313
  • 5.
    Adamo, Nasrat
    et al.
    Consultant Engineer, Norrköping, Sweden.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Sissakian, Varoujan
    Chief Researcehr, Department of Petroleum Engineering, Komar University of Science and Technology, Sulaimaniyah, KRG, Iraq.
    Climate Change and the Need for Future Research2022In: Water Resources in Iraq: Perspectives and Prognosis (ICWRPP 2022), Institute of Physics (IOP), 2022, article id 012029Conference paper (Refereed)
    Abstract [en]

    Climate Changes have impacted our planet since the beginning of time. These were manifested by cyclic Ice Ages and Warm Periods ever since. The changes were caused by natural forcing such as, continental drift, plate tectonics, major volcanic eruptions, and internal dynamics of earth and oceans interactions with the atmosphere. The present warm period, the “Holocene Epoch”, is not different from other such periods except for the sharp global warming which began at the onset of the industrial revolution. This was proven by scientific research to be due to anthropogenic drives, i.e., increased fossil fuel burning and increased Co2 and other Green House Gases (GHG) emissions into the atmosphere. These gases trap the sun radiation reflected from earth surface and result in higher earth temperature. The steep rate of rise in temperature trend since 1960s is directly linked to the use of much more fossil fuels in power production and transportation. This has led to more research to quantify the changes and their impacts on the environment and humans. This paper gives a brief history of the scientific research carried out hitherto and policy suggestions made so far to combat the negative impacts of the increasing global warming of the world. Needed future scientific research in this field is outlined, while at the same time suggesting the needs of Iraq of such research. This includes among other things, forming a regional scientific panel for the Middle East countries (ME. IPCC) for carrying out research on regional level, fostering research on national level, encouraging academics for climate change-oriented research and providing the necessary funds and facilities for such research.

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  • 6.
    Adamsson, Karolin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Kollektivtrafikknutpunkter i Göteborg ur ett genusperspektiv2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This paper will examine two public transportation hubs, as examples of public space, in Gothenburg, Sweden, from a gender perspective by investigate how gender equality is discussed in planning processes of hubs and to explore how hubs are used and perceived by men and women. The thesis has a qualitative and hermeneutic approach, with semi-structured interviews with key persons from the planning processes, and site observations and interviews with men and women using the hubs as the main data gathering methods. In the planning processes for the two cases the ambition was to create hubs that were welcoming for everyone, from a theoretical point of view this ambition could be dangerous from a gender perspective since a planning for everyone often leads to a planning for the man. In order to create hubs for everyone there was a focus for creating safety and increase accessibility for the disabled during the planning processes. The observations and the interviews on site shows that the hubs could be viewed as gender equal since the hubs were open to both men and women to use, but the hubs could also be viewed as not gender equal since women felt unsafe. The analysis shows that the social interaction on site is a crucial factor when defining a place as gender equal or not. The social interaction can be understood by gender contract. One conclusion is that there is a need for discussions about gender and its effect on experiences of public space, where gender contract is problematized. It will otherwise be hard to understand and change the interaction and the gender inequality will risk to consolidate.

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  • 7.
    Adnan Abdu, Jihad
    et al.
    Halmstad University, School of Information Technology.
    Lundström, Philip
    Halmstad University, School of Information Technology.
    Water Quality Device: Testing Through Electronic Measurements2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Water is the source of all life, but unfortunately, the water quality is getting only worse due to many factors like overuse, contamination, indifference and even by nature itself. By identifying the problem, we are one step closer to solving the problem, and that is why an intelligent water quality device is required to examine water and detect impurities within it. In this project, we are developing a device that uses an entirely new method to measure water quality. Even though the theory behind the device is very advanced, the device is still primitive in its functions and needs development to increase the usefulness and accuracy of the measurements!

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  • 8. Adrian, Brent
    et al.
    Werdelin, Lars
    Swedish Museum of Natural History, Department of Paleobiology.
    Grossman, Aryeh
    New Miocene Carnivora (Mammalia) from Moruorot and Kalodirr, Kenya2018In: Palaeontologia Electronica, ISSN 1935-3952, E-ISSN 1094-8074, Vol. 21Article in journal (Refereed)
    Abstract [en]

     We describe new carnivoran fossils from Kalodirr and Moruorot, two late Early

    Miocene sites in the Lothidok Formation of West Turkana, Kenya. The fossils include a

    new species of viverrid, Kichechia savagei  sp. nov., a new genus and species of felid,

    Katifelis nightingalei  gen. et sp. nov., and an unidentified musteloid. We also report

    new records of the amphicyonid Cynelos macrodon. These new fossils increase the

    known diversity of African Early Miocene carnivorans and highlight regional differences

    in Africa.

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  • 9.
    Adroit, Benjamin
    et al.
    Swedish Museum of Natural History, Department of Paleobiology.
    Grímsson, Friðgeir
    University of Vienna, Department of Botany and Biodiversity Research, 1030 Vienna, Austria.
    Suc, Jean-Pierre
    Sorbonne Université, CNRS-INSU, Institut des Sciences de la Terre Paris, ISTeP UMR7193, 75005 Paris, France.
    Escarguel, Gilles
    Laboratoire d'Ecologie des Hydrosystèmes Naturels et Anthropisés UMR CNRS 5023 LEHNA, Université Claude Bernard Lyon 1, France.
    Zetter, Reinhard
    University of Vienna, Department of Palaeontology, 1090 Vienna, Austria.
    Bouchal, Johannes M.
    University of Vienna, Department of Botany and Biodiversity Research, 1030 Vienna, Austria.
    Fauquette, Séverine
    ISEM, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France.
    Zhuang, Xin
    Institute for Atmospheric and Earth System Research (INAR), University of Helsinki, Finland.
    Djamali, Morteza
    Institut Méditerranéen de Biodiversité et d'Ecologie–IMBE (Aix Marseille Univ, Avignon Université, CNRS, IRD), Europôle de l'Arbois, Aix-en-Provence, France.
    Are morphological characteristics of Parrotia (Hamamelidaceae) pollen species diagnostic?2022In: Review of Palaeobotany and Palynology, ISSN 0034-6667, E-ISSN 1879-0615, Vol. 307, p. 104776-104776, article id 104776Article in journal (Refereed)
    Abstract [en]

    Parrotia persica is one of the most notable endemic relict tree species growing in the Hyrcanian forest at the southern Caspian Sea. The recent discovery of sibling species Parrotia subaequalis, occurring in the temperate forests of south-eastern China, offers the opportunity to compare their morphology and ecological preferences and to dig deeper into the paleophytogeographic history of the genus from a perspective. Since pollen morphology of these species would be essential to unravel the origin and evolution of these Arcto-Tertiary species, the present study aimed to investigate whether it is possible to segregate pollen from these two species. Therefore, a detailed combined light- and scanning electron microscopy-based pollen-analysis of each taxon was conducted, the pollen was described, measured, and compared using statistical approaches and principal component analyses to establish unbiased results. The correlation-based principal component analysis achieved for each species shows an overall good superposition of pollen grains measured in equatorial and polar views in the first principal plane, revealing that the P. persica pollen is morphometrically as homogeneous as that of P. subaequalis. Then, the significant difference, mainly driven by lumen density, has been highlighted between the two species. Ultimately, the cross-validation of the resulting two-species linear discriminants classifier shows that based upon this reference dataset, (sub)fossil pollen grain can now be confidently assigned to either of the two species with an 85.8% correct-assignment rate. This opens new doors in the affiliation of fossil Parrotia pollen and suggests that previous pollen records need to be revised.

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  • 10. Adroit, Benjamin
    et al.
    Teodoridis, Vasilis
    Güner, H. Tuncay
    Denk, Thomas
    Swedish Museum of Natural History, Department of Paleobiology.
    Patterns of insect damage types reflect complex environmental signal in Miocene forest biomes of Central Europe and the Mediterranean2021In: Global and Planetary Change, ISSN 0921-8181, E-ISSN 1872-6364, Vol. 199, article id 103451Article in journal (Refereed)
    Abstract [en]

    Ecosystems are defined by the community of living organisms and how they interact together and with theirenvironment. Insects and plants are key taxa in terrestrial ecosystems and their network determines the trophicstructure of the environment. However, what drives the interactions between plants and insects in modern andfossil ecosystems is not well understood. In this study, we analyzed insect damage richness and frequency in 5000 fossil leaves deposited during the early Miocene at 20–17 Ma along a latitudinal gradient from Europe (twolocalities in Czech Republic) to Turkey (one locality) in a temperate climate setting. Damage frequency wasmainly linked with abiotic factors (temperature, precipitation seasonality) whereas damage richness was mainlylinked with biotic factors (plant richness, biome). Univariate analysis of insect damage types consistently suggested closer trophic similarity between the Mediterranean and either the one or the other Central European plant assemblage. In contrast, multivariate analysis of all insect damage types indicated closer similarity between the two Central European sites highlighting the importance of biogeographic legacy and geographic closeness to the plant-insect interaction patterns. Our results underscore the high complexity of the herbivory network andcall for careful interpretations of plant-insect interaction patterns in palaeoecological studies. Finally, comparing the trophic similarity between different localities using total evidence plots as done in this work might be apromising complementary method in comparative studies of plant-insect interactions.

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    Adroit et al. 2021
  • 11.
    Agic, Heda
    et al.
    Univ Calif Santa Barbara, Dept Earth Sci, Santa Barbara, CA 93106 USA..
    Hogstrom, Anette E. S.
    UiT Arctic Univ Norway, Arctic Univ Museum Norway, Tromso, Norway..
    Jensen, Soren
    Univ Extremadura, Area Paleontol, Badajoz, Spain..
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Vickers-Rich, Patricia
    Monash Univ, Sch Earth Atmosphere & Environm, Clayton, Vic, Australia.;Swinburne Univ Technol, Sch Sci, Dept Chem & Biotechnol, Hawthorn, Vic, Australia..
    Hall, Michael
    Monash Univ, Sch Earth Atmosphere & Environm, Clayton, Vic, Australia..
    Matthews, Jack J.
    Oxford Univ Museum Nat Hist, Oxford, England..
    Meinhold, Guido
    TU Bergakad Freiberg, Inst Geol, Freiberg, Germany.;Univ Gottingen, Dept Sedimentol & Environm Geol, Gottingen, Germany..
    Hoyberget, Magne
    Rennesveien 14, Mandal, Norway..
    Taylor, Wendy L.
    Univ Cape Town, Dept Geol Sci, Rondebosch, South Africa..
    Late Ediacaran occurrences of the organic-walled microfossils Granomarginata and flask-shaped Lagoenaforma collaris gen. et sp. nov.2022In: Geological Magazine, ISSN 0016-7568, E-ISSN 1469-5081, Vol. 159, no 7, p. 1071-1092, article id PII S0016756821001096Article in journal (Refereed)
    Abstract [en]

    New occurrences of flask-shaped and envelope-bearing microfossils, including the predominantly Cambrian taxon Granomarginata, are reported from new localities, as well as from earlier in time (Ediacaran) than previously known. The stratigraphic range of Granomarginata extends into the Cambrian System, where it had a cosmopolitan distribution. This newly reported Ediacaran record includes areas from Norway (Baltica), Newfoundland (Avalonia) and Namibia (adjacent to the Kalahari Craton), and puts the oldest global occurrence of Granomarginata in the Indreelva Member (< 563 Ma) of the Stahpogieddi Formation on the Digermulen Peninsula, Arctic Norway. Although Granomarginata is rare within the assemblage, these new occurrences together with previously reported occurrences from India and Poland, suggest a potentially widespread palaeogeographic distribution of Granomarginata through the middle-late Ediacaran interval. A new flask-shaped microfossil Lagoenaforma collaris gen. et sp. nov. is also reported in horizons containing Granomarginata from the Stahpogieddi Formation in Norway and the Dabis Formation in Namibia, and flask-shaped fossils are also found in the Gibbett Hill Formation in Newfoundland. The Granomarginata-Lagoenaforma association, in addition to a low-diversity organic-walled microfossil assemblage, occurs in the strata postdating the Shuram carbon isotope excursion, and may eventually be of use in terminal Ediacaran biostratigraphy. These older occurrences of Granomarginata add to a growing record of body fossil taxa spanning the Ediacaran-Cambrian boundary.

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    FULLTEXT01
  • 12.
    Agic, Heda
    et al.
    Department of Earth Science, University of California at Santa Barbara, Santa Barbara, USA.
    Högström, Anette
    Tromsø Universitetsmuseum.
    Jensen, Sören
    Área de Paleontología, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, Spain.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Meinhold, Guido
    Geowissenschaftliches Zentrum der Universität Göttingen, Germany.
    Taylor, Wendy L.
    Department of Geological Sciences, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa.
    Palacios, Teodor
    Área de Paleontología, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, Spain.
    Høyberget, Magne
    Rennesveien 14, N-4513 Mandal, Norway.
    Life through the 'Varanger ice ages': microfossil record of late Neoproterozoic glacial-interglacial units from arctic Norway2018In: Geological Society of America Abstracts with Programs, Geological Society of America, 2018, Vol. 50Conference paper (Other academic)
    Abstract [en]

    The late Neoproterozoic strata in Finnmark (Arctic Norway) provide a good sedimentary record of Neoproterozoic glaciations on the Baltica paleocontinent. The lower Vestertana Group exposed on the Digermulen Peninsula contains two glaciogenic units, the Smalfjord and Mortensnes formations. Chemostratigraphic correlation dated the Smalfjord diamictite to the Marinoan glaciation (650-635 Ma), yet its age was also proposed to be older, per correlation to glacial units in central and southern Scandinavia. The diamictites are bracketing shales and siltstones of the interglacial Nyborg Formation. Stratigraphic, paleontological, and sedimentological data are presented from the interglacial-glacial succession, investigated by the Digermulen Early Life Research Group. Palynological analysis yielded well-preserved organic-walled microfossils (OWM) from the Nyborg Fm., and from fine-grained diamictite matrix in the Mortensnes Fm. via a modified extraction method.

    The interglacial Nyborg Fm. hosts a moderate diversity assemblage of prokaryotic and eukaryotic OWM, as well as acanthomorphic acritarchs such as Ceratosphaeridium, ?Cavaspina, and a novel process-bearing form. Organically preserved, enigmatic multicellular eukaryotic fossils occur in the upper Nyborg Fm. The Mortensens glacial assemblage is less diverse and contains bacterial filaments, leiosphaerids, toroidal forms, and Micrhystridium-type minute acanthomorphs.

    The presence of Doushantuo-Pertatataka type acritarchs in the Nyborg Fm., and small acanthomorphs in the Mortensnes diamictite corroborate an early Ediacaran age for the interglacial-glacial succession on Digermulen. In addition to the trace fossil and body-fossil record of Ediacara-biota in the overlying Stáhpogieddi Formation, the microfossil biostratigraphy suggests Marinoan and Gaskiers glaciation equivalent ages of the Varanger glaciations in Finnmark. Protistan diversity in the succession declined through and following the glaciation, until late Ediacaran.

  • 13.
    Agic, Heda
    et al.
    Univ Durham, Dept Earth Sci, Durham, England..
    Jensen, Soren
    Univ Extremadura, Fac Ciencias, Area Paleontol, Badajoz, Spain..
    Meinhold, Guido
    TU Bergakad Freiberg, Inst Geol, Freiberg, Germany.;Univ Gottingen, Dept Sedimentol & Environm Geol, Gottingen, Germany..
    Hogstrom, Anette E. S.
    Arctic Univ Museum Norway, UiT The Arctic Univ Norway, Tromso, Norway..
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Hoyberget, Magne
    Palacios, Teodoro
    Univ Extremadura, Fac Ciencias, Area Paleontol, Badajoz, Spain..
    Taylor, Wendy L.
    Univ Cape Town, Dept Geol Sci, Rondebosch, South Africa..
    Life through an Ediacaran glaciation: Shale- and diamictite-hosted organic-walled microfossil assemblages from the late Neoproterozoic of the Tanafjorden area, northern Norway2024In: Palaeogeography, Palaeoclimatology, Palaeoecology, ISSN 0031-0182, E-ISSN 1872-616X, Vol. 635, article id 111956Article in journal (Refereed)
    Abstract [en]

    New organic-walled microfossil (OWM) assemblages are reported from upper Neoproterozoic glacial and interglacial siliciclastic deposits in Finnmark, northern Norway. A nearly continuous sedimentary succession of the Vestertana Group contains two glaciogenic units, the Smalfjorden and Mortensnes formations, interpreted as end-Cryogenian Marinoan and Ediacaran glaciations, respectively. We investigated the OWM record in the Nyborg, Mortensnes, and St ' ahpogieddi formations to assess the impact of a glacial interval on the diversity of microscopic eukaryotes. A modified acid-extraction technique was applied to recover OWM from the diamictite matrix. The upper Nyborg Formation contains morphologically complex Doushantuo-Pertatataka acritarchs (DPA), restricting the age of the Nyborg Formation to early-mid Ediacaran. DPA occur below the dolostones that record a negative carbon isotope excursion correlated with the Shuram anomaly and below a glacial diamictite. A decline in species richness and compositional change is observed in the Mortensnes glacial assemblage. DPA are replaced by bacterial filaments and cell aggregates. The overlying Indreelva Member, St ' ahpogieddi Formation contains Ediacara-type biota and palaeopascichnids, but only a depauperate OWM assemblage of leiosphaerids and flask-shaped microfossils characteristic of the late Ediacaran.The succession of assemblages in the Vestertana Group demonstrates a turnover from large eukaryotic OWM to a microbial community in the glacial interval, to a low diversity post-glacial assemblage during the rise of macroscopic life. We compared the Vestertana record to global DPA occurrences. Although one DPA assemblage zone postdates the Shuram excursion, no DPA occur above Ediacaran glacial diamictites in successions where those deposits are present. Considering this, and the community changes in the Vestertana succession, we suggest that DPA were affected by the onset of an Ediacaran glaciation. Lastly, we combined the biostratigraphic markers in the Vestertana Group to constrain the age of the Mortensnes diamictite.

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  • 14.
    Agic, Heda
    et al.
    Department of Earth Science, University of California at Santa Barbara, Santa Barbara, USA.
    Moczydłowska, Małgorzata
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Högström, Anette
    Tromsø Universitetsmuseum.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Jensen, Sören
    Área de Paleontología, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, Spain.
    Meinhold, Guido
    Geowissenschaftliches Zentrum der Universität Göttingen, Germany.
    Palacios, Teodor
    Área de Paleontología, Universidad de Extremadura, Avenida de Elvas s/n, Badajoz, Spain.
    Taylor, Wendy L.
    Department of Geological Sciences, University of Cape Town, Private Bag X3, Rondebosch 7701, South Africa.
    Novis, Linn K.
    Tromsø Universitetsmuseum.
    Unusual organic-walled microfossil from the late Neoproterozoic Nyborg Formation, Digermulen Peninsula, Arctic Norway2017In: ISECT 2017, 2017Conference paper (Other academic)
    Abstract [en]

    The late Neoproterozoic Nyborg Formation is exposed in the Tanafjord area, Finnmark, Arctic Norway, on Digermulen and Varanger Peninsulas. The succession is composed of ~400 m of interbedded shales, siltstone and purple to grey sandstone, deposited between Neoproterozoic low latitude glacial deposits. The Nyborg Fm. lies on top of the Smalfjord diamictite, and is overlain by the Mortensnes diamictite (the latter was attributed to both Marinoan (650-635 Ma) and Gaskiers (579 Ma) glaciations) and the Ediacaran-Cambrian Stáhpogieddi Formation. Thus, the Nyborg Fm. represents late Neoproterozoic, probably the last Cryogenian interglacial interval. Presented material was collected in 2014 by members of Digermulen Early Life Research Group, from organic-rich, grey-green shales and siltstones of the Nyborg Mbr. D, uppermost Nyborg Fm. between Árasulluokta and Guvssájohka valleys. Organic-walled microfossils were extracted from shale via standard palynological acetolysis in hydrofluoric acid, and studied via light and scanning electron microscopy. Microfossils from the Nyborg Fm. include Synsphaeridium-type aggregated cells, unbranched bacterial filaments (Polythrichoides and Siphonophycus), sphaeromorph and envelope-bearing acritarchs (leiosphaerids, Stictosphaeridium, Simia), and previously unrecognized aggregated tubular microfossils. These taxa are long-ranging, but common in glacial-interglacial units worldwide, and thus broadly corroborate the Cryogenian age of the Nyborg sediments. The novel fossil, up to 300 μm in size, is a parenchymatous meshwork of interconnected organic-walled tubes that terminate in cup-shaped apices 4-11 µm in diameter. Irregular tube clusters are truncated both in macerates and in thin sections, suggesting post mortem transport. Elemental EDXS analysis indicates that extracted meshwork microfossils are predominantly composed of carbonaceous material and also associated with small amounts of titanium and vanadium. Considering the branching and adjoined body plan of carbonaceous fossil, it was likely multicellular and of eukaryotic affinity. As such, it may represent an important step in the evolution of complex multicellularity and morphological complexity several million years before the appearance of Ediacaran organisms.

  • 15.
    Agić, Heda
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology. Univ Calif Santa Barbara, Dept Earth Sci, Santa Barbara, CA 93106 USA.
    Högström, Anette E. S.
    UiT Arctic Univ Norway, Arctic Univ Museum Norway, N-9037 Tromso, Norway.
    Moczydlowska, Malgorzata
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Palaeobiology.
    Jensen, Sören
    Univ Extremadura, Area Paleontol, E-06006 Badajoz, Spain.
    Palacios, Teodoro
    Univ Extremadura, Area Paleontol, E-06006 Badajoz, Spain.
    Meinhold, Guido
    Keele Univ, Sch Geog Geol & Environm, Keele ST5 5BG, Staffs, England;Univ Gottingen, Dept Sedimentol & Environm Geol, Goldschmidtstr 3, D-37077 Gottingen, Germany.
    Ebbestad, Jan Ove R.
    Uppsala University, Music and Museums, Museum of Evolution.
    Taylor, Wendy L.
    Univ Cape Town, Dept Geol Sci, ZA-7701 Rondebosch, South Africa.
    Höyberget, Magne
    Rennesveien 14, N-4513 Mandal, Norway.
    Organically-preserved multicellular eukaryote from the early Ediacaran Nyborg Formation, Arctic Norway2019In: Scientific Reports, E-ISSN 2045-2322, Vol. 9, article id 14659Article in journal (Refereed)
    Abstract [en]

    Eukaryotic multicellularity originated in the Mesoproterozoic Era and evolved multiple times since, yet early multicellular fossils are scarce until the terminal Neoproterozoic and often restricted to cases of exceptional preservation. Here we describe unusual organically-preserved fossils from mudrocks, that provide support for the presence of organisms with differentiated cells (potentially an epithelial layer) in the late Neoproterozoic. Cyathinema digermulense gen. et sp. nov. from the Nyborg Formation, Vestertana Group, Digermulen Peninsula in Arctic Norway, is a new carbonaceous organ-taxon which consists of stacked tubes with cup-shaped ends. It represents parts of a larger organism (multicellular eukaryote or a colony), likely with greater preservation potential than its other elements. Arrangement of open-ended tubes invites comparison with cells of an epithelial layer present in a variety of eukaryotic clades. This tissue may have benefitted the organism in: avoiding overgrowth, limiting fouling, reproduction, or water filtration. C. digermulense shares characteristics with extant and fossil groups including red algae and their fossils, demosponge larvae and putative sponge fossils, colonial protists, and nematophytes. Regardless of its precise affinity, C. digermulense was a complex and likely benthic marine eukaryote exhibiting cellular differentiation, and a rare occurrence of early multicellularity outside of Konservat-Lagerstatten.

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  • 16.
    Ahlgren, Joakim
    et al.
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry, Analytical Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Limnology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry.
    Reitzel, Kasper
    Danielsson, Rolf
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry, Analytical Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Limnology. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry.
    Gogoll, Adolf
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry, Analytical Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    Rydin, Emil
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Chemistry, Department of Physical and Analytical Chemistry, Analytical Chemistry. Department of Biochemistry and Organic Chemistry, Organic Chemistry I. Faculty of Science and Technology, Biology, Department of Ecology and Evolution, Limnology.
    Biogenic phosphorus in oligotropic mountain lake sediments: Differences in composition measured with NMR spectroscopy2006In: Water Research, no 40, p. 3705-3712Article in journal (Refereed)
  • 17.
    Ahlgren Mattsson, David
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Jämförelse av portrycksmätning i Uppsalalera mellan portrycksmätare och dissipationstest2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The pore pressure is an important parameter for determining the properties of thesoil, such as drainage, permeability and stability (since the pore pressure has aneffect on the effective stress in the soil). The pore pressure can be measured withpore pressure gauges but it can also be measured during a Cone penetration test(CPT) with a dissipation test. Advantages of a dissipation test compared tomeasurement with traditional pore pressure gauges would be that it would save timeand money, since you don’t have to press down pore pressure gauges and then waitto get the pore pressure from them, instead the pore pressure can be measuredduring probing with CPT.The purpose of this project is to compare pore pressure measurements betweenpore pressure measurements with BAT-tips and dissipation test during CPT probing,to see how good measured values the dissipation tests will provide and if theyeventually can supersede pore pressure gauges for pore pressure measurements.The field tests of the methods were done in Uppsala clay, on a site in Kungsängen inUppsala.Two stations with BAT-tips at 5 meters, 7.5 meters and 10 meters depth wereinstalled in the clay. Probing with CPT was then carried out, by stopping the CPT atthe same depth as the BAT-tips. Measurements with the CPT were done at thesedepths for just over 24 hours, to allow the generated excess pore pressure createdwhen the cone is pushed into the clay to disperse to the sides. The equilibrium porepressure is the pore pressure that remains after the generated pore pressure hasdissipated. The pore pressure from the two different methods was then compared tosee how close the dissipation test results were to the values from the pore pressuremeasurements with the BAT tips.The result of the dissipation tests was that none of them reached the referencevalues from the BAT-tips after 24 hours. Depending on the chosen application class,the dissipation tests are within the permitted minimum accuracy. Dissipation tests areprobably not practically applicable to soils with low permeability.

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  • 18.
    Ahlgren, Sara
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Changes in size distribution of lakes in the Nadym catchment, northern Russia2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Because of climate change and resource development there is an ongoing increase in the attention directed towards high latitude areas. Over the last years, warming in the Arctic has accelerated quickly. The warming climate can possibly lead to thawing of ground ice, which in turn leads to alterations of the cryosphere. This can have a huge influence on the terrestrial hydrology of the Arctic and, more specifically, on the presence and distribution of lakes in arctic regions since both are coupled to subsurface ice. In this thesis data from remote sensing were used to look at the change in the size distribution of lakes for the Nadym catchment in northern Russia. The aim was to find out if there has been an increase or decrease in the number of lakes in the area over the past years. Results suggest that there were 229 lakes less (representing a 4% decrease) in 2007–2009 compared to 1987, indicating that lakes are slowly disappearing. Also, the total lake surface area decreased with 5%. Almost half of the lakes that disappeared (49%) can be found among the smallest lakes ranging between 10–20 ha. In the entire catchment this size class was also found to be the class with by far the highest number of lakes.

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  • 19.
    Ahlqvist, Ola
    Stockholm University, Faculty of Science, Department of Physical Geography and Quaternary Geology.
    Context Sensitive Transformation of Geographic Information2000Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This research is concerned with theoretical and methodological aspects of geographic information transformation between different user contexts. In this dissertation I present theories and methodological approaches that enable a context sensititve use and reuse of geographic data in geographic information systems.

    A primary motive for the reported research is that the patrons interested in answering environmental questions have increased in number and been diversified during the last 10-15 years. The interest from international, national and regional authorities together with multinational and national corporations embrace a range of spatial and temporal scales from global to local, and from many-year/-decade perspectives to real time applications. These differences in spatial and temporal detail will be expressed as rather different questions towards existing data. It is expected that geographic information systems will be able to integrate a large number of diverse data to answer current and future geographic questions and support spatial decision processes. However, there are still important deficiencies in contemporary theories and methods for geographic information integration

    Literature studies and preliminary experiments suggested that any transformation between different users’ contexts would change either the thematic, spatial or temporal detail, and the result would include some amount of semantic uncertainty. Consequently, the reported experiments are separated into studies of change in either spatial or thematic detail. The scope concerned with thematic detatil searched for approaches to represent indiscernibility between categories, and the scope concerned with spatial detail studied semantic effects caused by changing spatial granularity.

    The findings make several contributions to the current knowledge about transforming geographic information between users’ contexts. When changing the categorical resolution of a geographic dataset, it is possible to represent cases of indiscernibility using novel methods of rough classification described in the thesis. The use of rough classification methods together with manual landscape interpretations made it possible to evaluate semantic uncertainty in geographic data. Such evaluations of spatially aggregated geographic data sets show both predictable and non-predictable effects. and these effects may vary for different environmental variables.

    Development of methods that integrate crisp, fuzzy and rough data enables spatial decision support systems to consider various aspects of semantic uncertainty. By explicitly representing crisp, fuzzy and rough relations between datasets, a deeper semantic meaning is given to geographic databasses. The explicit representation of semantic relations is called a Geographic Concept Topology and is held as a viable tool for context transformation and full integration of geographic datasets.

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  • 20.
    Ahmadlou, Mohammad
    et al.
    GIS Department, Geodesy and Geomatics Faculty, K.N. Toosi University of Technology, Tehran, Iran.
    Karimi, Mohammad
    GIS Department, Geodesy and Geomatics Faculty, K.N. Toosi University of Technology, Tehran, Iran.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    The use of maximum entropy and ecological niche factor analysis to decrease uncertainties in samples for urban gain models2023In: GIScience & Remote Sensing, ISSN 1548-1603, E-ISSN 1943-7226, Vol. 60, no 1, article id 2222980Article in journal (Refereed)
    Abstract [en]

    Uncertainty is a common problem in spatial modeling and geographical information systems (GIS). Furthermore, urban gain modeling (UGM) contains various dimensions and components of uncertainties. Data sampling is important in UGM, and may cause the results of the models to contain many uncertainties as well as affects their precision and accuracy. A poorly sampled or biased dataset can lead to inaccurate predictions and decreased performance of the models. This paper aims to present and develop novel strategies for sampling and building training datasets that can enhance the performance of data-driven models. In other words, the present study used maximum entropy (ME) and ecological niche factor analysis (ENFA) models to select pure non-change samples with minimal uncertainty for training datasets in UGM of Isfahan and Tabriz cities in Iran. The urban gain of two time intervals of 1992–2002 and 2002–2012 were used for Tabriz City and two time intervals of 1994–2004 and 2004–2014 for Isfahan City. Nine and 14 urban gain drivers were used in the UGM of Isfahan and Tabriz cities, respectively. After the ME and ENFA models produced a training dataset with change and non-change samples with the lowest uncertainty, three well-known models, namely random forest (RF), artificial neural network (ANN), and support vector machine (SVM) were used for the modeling. Moreover, the ME and ENFA models that were used to investigate the uncertainty of the sampling procedure were used as the one-class prediction models. Compared to extant studies, the proposed ME – based sampling strategy increased the area under the receiver operating characteristic curve (AUROC), figure of merit, producer’s accuracy, and overall accuracy by 5.5%, 5%, 5%, and 3%, respectively, in the validation phase of Isfahan City and by 5%, 6%, 14%, and 17%, respectively, for Tabriz City. For Isfahan, the accuracies of ME (AUROC = 0.649) and ENFA (AUROC = 0.661) one – class models were closer to that of the ANN – ME (AUROC = 0.646), ANN – ENFA (AUROC = 0.619), and RF – ENFA (AUROC = 0.631) models but differed significantly from that of the RF – ME (AUROC = 0.737) model. For Tabriz, the accuracies of ME (AUROC = 0.657) and ENFA (AUROC = 0.688) one – class models were lower than that of the two class RF-ME (AUROC = 0.852), and ANN-ME (AUROC = 0.778) models. The results showed that the ME model was able to identify relatively pure non-change samples and properly remove impure non-change samples from the training dataset. This study discovered that binary models are preferable to one-class models, and showed that an optimal sampling strategy is an essential step in UGM as it can decrease uncertainty. As such, modelers must adopt efficient sampling methods.

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  • 21.
    Akrawi, Narin
    et al.
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Ciechowicz, Michelle
    Södertörn University, School of Natural Sciences, Technology and Environmental Studies.
    Fotbollsturism: En studie om fotbollsturisters upplevelse och tillfredställelse2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This is a study made by two students for their bachelor theses in Tourism at Södertörn University, Sweden. The study investigates weather the theoretical characteristic features of a sport tourist is inconsistent with reality. The study also investigates factors that sport tourist consider important during a football trip to achieve a satisfying experience. By identifying specific element of the phenomenon increase knowledge and development of sport tourism. The method chosen for the study was qualitative interviews which where performed with twenty respondents, each respondent travel to Lisbon, Portugal to attend the quarter- finals of Champions League between SL Benfica and FC Bayer München, 13 April 2016. The interview material was interpreted and later merges with previous research and theories in order to investigate and identify the phenomenon. The result of the study showed that the theoretical and previous research that have been presented on characteristic features of a sport tourist do not or partly match the respondents in this study. This study also showed that factors that sport tourist consider important as e.g. good seats, security, transport, good company, good atmosphere, other supporters and supporting their favourite football team, are the factors that contribute and makes a satisfying, memorable and positive experience trip.

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  • 22.
    Al-Bahrani, Hussein Shakir
    et al.
    Faculty of Engineering, University of Kufa, Najaf, Iraq.
    Al-Rammahi, Ali Hussein
    Faculty of Engineering, University of Kufa, Najaf, Iraq.
    Al-Mamoori, Sohaib Kareem
    Department of Environmental Planning, Faculty of Physical Planning, University of Kufa, Najaf, Iraq.
    Al-Maliki, Laheab A.
    Department of Regional Planning, Faculty of Physical Planning, University of Kufa, Najaf, Iraq.
    Al-Ansari, Nadhir
    Luleå University of Technology, Department of Civil, Environmental and Natural Resources Engineering, Mining and Geotechnical Engineering.
    Groundwater detection and classification using remote sensing and GIS in Najaf, Iraq2022In: Groundwater for Sustainable Development, ISSN 2352-801X, Vol. 19, article id 100838Article in journal (Refereed)
    Abstract [en]

    Due to the shortage of fresh surface water caused by climate change, groundwater has become a vital water supply for household, agricultural, and industrial use. Alternative methods for determining groundwater depth, amount, and quality at a lower cost and less effort are critical. This study aims to determine the depth and kind of groundwater in Najaf City, Iraq, using Aqua detector remote sensing device. Thirty-nine sample locations were chosen in rural and urban regions to cover the city’s 441.23 square kilometres. Five geographic models of groundwater depth and type were created using the Inverse Distance Weighting (IDW) interpolation method in ArcGIS software. The results indicate that groundwater is available across the study region, beginning at 100 m and lower depths. Additionally, it has been found that the nature of groundwater fluctuates with the location and depth. The findings of this study aid in selecting wells locations and depths in the study region that generate maximum quality and quantity of groundwater.

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  • 23.
    Aldenius, Malin
    et al.
    Lund Univ, Sweden; K2 Swedish Knowledge Ctr Publ Transport, Sweden.
    Tsaxiri, Panagiota
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, Faculty of Arts and Sciences. K2 Swedish Knowledge Ctr Publ Transport, Sweden; Swedish Natl Rd & Transport Res Inst VTI, Linkoping, Sweden.
    Lidestam, Helene
    Linköping University, Department of Management and Engineering, Production Economics. Linköping University, Faculty of Science & Engineering. K2 Swedish Knowledge Ctr Publ Transport, Sweden; Swedish Natl Rd & Transport Res Inst VTI, Linkoping, Sweden.
    The role of environmental requirements in Swedish public procurement of bus transports2022In: International Journal of Sustainable Transportation, ISSN 1556-8318, E-ISSN 1556-8334, Vol. 16, no 5, p. 391-405Article in journal (Refereed)
    Abstract [en]

    The transport sector needs to become sustainable and public transport has an important role to play. Green public procurement has proven to have great potential to influence the transition to a sustainable public transport sector. Sweden is a good example of a country that uses public procurement in the public transport sector to a large extent and has at the same time come far in the transition to renewable fuel. The aim of this study is to examine what role public transport authorities (PTAs) can have in supporting more environmentally sustainable public transport through public procurement. This was done by a content analysis regarding the expressions of environmental requirements historically, over a ten-year period, in tender documents in Sweden, followed by a workshop where the implications of the findings and future tender processes were discussed with relevant actors. The results showed that all the environmental requirements have become stricter during the studied period, but indicate a tendency for higher use of environmental requirements in tendering of larger areas as well as in tendering of public transport within cities. Specifically, for requirements for fuel, the same tenders also use specific requirements to a higher extent. However, the subsequent workshop discussions indicated that the use of specific requirements is one reason for disagreement among involved actors. Overall, this study of the Swedish public transport case showed that PTAs have a large potential to support more environmentally sustainable solutions using environmental requirements in public procurement.

  • 24.
    Aldén, Liselotte
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Nätverket för vindbruk.
    Ottvall, Richard
    Da Silva Soares, José Pedro
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Nätverket för vindbruk.
    Klein, Jason
    Nätverket för vindbruk.
    Liljenfeldt, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Nätverket för vindbruk.
    Samexistens örnar och vindkraft på Gotland2017Report (Other (popular science, discussion, etc.))
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  • 25.
    Aldén, Liselotte
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Nätverket för vindbruk.
    Ottvall, Richard
    Da Silva Soares, José Pedro
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Nätverket för vindbruk.
    Klein, Jason
    Nätverket för vindbruk.
    Liljenfeldt, Johanna
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Nätverket för vindbruk.
    Samexistens örnar och vindkraft på Gotland2017Report (Other (popular science, discussion, etc.))
  • 26.
    Aldén, Liselotte
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Noden för utbildning- och kompetensfrågor inom Nätverket för vindbruk.
    Ridbäck, Ulrika
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Engberg Ekman, Marita
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    En analys av Vindkraftsteknikerutbildningar i Sverige åren 2016–20242020Report (Other (popular science, discussion, etc.))
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  • 27.
    Aleklett, Kjell
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    Höök, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems. Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, Natural Resources and Sustainable Development.
    Jakobsson, Kristofer
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    Lardelli, Michael
    School of Molecular and Biomedical Science, University of Adelaide, Australia.
    Snowden, Simon
    Management School, University of Liverpool, United Kingdom.
    Söderbergh, Bengt
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Global Energy Systems.
    The Peak of the Oil Age: Analyzing the world oil production Reference Scenario in World Energy Outlook 20082010In: Energy Policy, ISSN 0301-4215, E-ISSN 1873-6777, Vol. 38, no 3, p. 1398-1414Article in journal (Refereed)
    Abstract [en]

    The assessment of future global oil production presented in the IEA’s World Energy Outlook 2008 (WEO 2008) is divided in to 6 fractions; four relate to crude oil, one to non-conventional oil, and the final fraction is natural-gas-liquids (NGL). Using the production parameter, depletion-rate-of-recoverable- resources, we have analyzed the four crude oil fractions and found that the 75 Mb/d of crude oil production forecast for year 2030 appears significantly overstated, and is more likely to be in the region of 55 Mb/d. Moreover, an alysis of the other fractions strongly suggests lower than expected production levels. In total, our analysis points to a world oil supply in 2030 of 75Mb/d, some 26 Mb/d lower than the IEA predicts. The connection between economic growth and energy use is fundamental in the IEA’s present modeling approach. Since our forecast sees little chance of a significant increase in global oil production, our findings suggest that the ‘‘policy makers, investors and end users’’ to whom WEO 2008 is addressed should rethink their future plans for economic growth. The fact that global oil production has very probably passed its maximum implies that we have reached the Peak of the Oil Age.

  • 28.
    Alexander, Mannelqvist
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Paleontology and Sedimentology of the Alum Shale Formation at Björnberget, Västerbotten County, Sweden2016Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A new locality of the Alum Shale Formation at Björnberget, Västerbotten County, of the lower allochthon of the Caledonian front is described herein. Two new species of acrotretid brachiopods were found. Tingitanella vilhelminia n. sp. adds another species to the monospecific genus. T. vilhelminia also extend the genus distribution to Sweden. Anabolotreta furcatus n. sp. is the first member of the genus found in Sweden and extend the stratigraphic range to Stage 5 of Cambrian Series 3. It also exhibits an unusual bifurcating shell structure described for the first time herein. One trilobite was found at the locality, Acadoparadoxides torelli, indicating that the exposures at Björnberget belong to the upper Acadoparadoxides (Baltoparadoxides) oelandicus superzone. The fauna found is impoverished in comparison to the fauna that has been described from Jämtland and reflects the depositional environment on the deep outer shelf with low sediment input.

    The known exposure at Granberget, close to Björnberget, is described with respect to the paleontology and sedimentology of the section. The fauna at Granberget could be extended with two new species of agnostids, Hypagnostus lingula and Hypagnostus mammillatus, to a total of six taxa of trilobites. The depositional environment was periodically affected by storms, depositing limestone layers composed of skeletal material. The Alum shale does not exhibit these sedimentary structures and have probably lost the majority of the them during diagenesis.

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  • 29.
    Alhalabi, Wafa A.
    et al.
    Univ Sao Paulo, Dept Biol, FFCLRP, Ave Bandeirantes 3900, BR-14040901 Ribeirao Preto, SP, Brazil..
    Bardet, Nathalie
    CR2P Ctr Rech Paleontol Paris, Museum Natl Hist Nat, CP38,57 Rue Cuvier, F-75005 Paris, France..
    Sachs, Sven
    Nat Kundemuseum Bielefeld, Abt Geowissensch, Adenauerpl 2, D-33602 Bielefeld, Germany..
    Kear, Benjamin P.
    Uppsala University, Music and Museums, Museum of Evolution.
    Joude, Issam B.
    Morrison Hershfield, 2932 Baseline Rd, Ottawa, ON K2H 1B1, Canada..
    Yazbek, Muhammed K.
    Al Baath Univ, Fac Sci, Geol Dept, Damascus Aleppo Highway, Homs, Syria..
    Godoy, Pedro L.
    Univ Sao Paulo, Inst Biosci, Dept Zool, BR-05508090 Sao Paulo, SP, Brazil.;SUNY Stony Brook, Dept Anat Sci, Stony Brook, NY 11794 USA..
    Langer, Max C.
    Univ Sao Paulo, Dept Biol, FFCLRP, Ave Bandeirantes 3900, BR-14040901 Ribeirao Preto, SP, Brazil..
    Recovering lost time in Syria: New Late Cretaceous (Coniacian-Santonian) elasmosaurid remains from the Palmyrides mountain chain2024In: Cretaceous research (Print), ISSN 0195-6671, E-ISSN 1095-998X, Vol. 159, article id 105871Article in journal (Refereed)
    Abstract [en]

    Despite its relatively limited vertebrate fossil record, Syria currently records the largest number of documented Mesozoic marine reptile occurrences among the Middle Eastern countries. In particular, the phosphatic deposits of the Palmyrides mountain chain have yielded fossils of aquatic squamates, bothremydid and chelonioid marine turtles, as well as elasmosaurid plesiosaurs. Nevertheless, new discoveries have not been reported for the last two decades. Here, we describe the partial skeleton of an elasmosaurid plesiosaur from Syria, which comprises the middle and posterior cervical series, together with articulated pectoral, dorsal and anterior caudal parts of the vertebral column, with associated rib fragments. The fossil was excavated from Coniacian-Santonian phosphatic deposits of the Al Sawaneh el Charquieh mines, in the central part of the southwestern Palmyrides, about 200 km northeast of Damascus. The specimen can be assigned to Elasmosauridae based on the cervical centra morphology and, although incomplete, is significant because it not only represents likely the oldest, but also the currently most complete plesiosaur skeleton recovered from the Middle East. (c) 2024 Elsevier Ltd. All rights reserved.

  • 30.
    Alijagic, Andi
    et al.
    Örebro University, School of Science and Technology. Inflammatory Response and Infection Susceptibility Centre (iRiSC), Örebro University, Örebro, Sweden; School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Suljević, Damir
    Department of Biology, Faculty of Science, University of Sarajevo, Sarajevo, Bosnia and Herzegovina.
    Fočak, Muhamed
    Department of Biology, Faculty of Science, University of Sarajevo, Sarajevo, Bosnia and Herzegovina.
    Sulejmanović, Jasmina
    Department of Chemistry, Faculty of Science, University of Sarajevo, Sarajevo, Bosnia and Herzegovina.
    Šehović, Elma
    Department of Chemistry, Faculty of Science, University of Sarajevo, Sarajevo, Bosnia and Herzegovina.
    Särndahl, Eva
    Örebro University, School of Medical Sciences. Inflammatory Response and Infection Susceptibility Centre (iRiSC).
    Engwall, Magnus
    Örebro University, School of Science and Technology.
    The triple exposure nexus of microplastic particles, plastic-associated chemicals, and environmental pollutants from a human health perspective2024In: Environment International, ISSN 0160-4120, E-ISSN 1873-6750, Vol. 188, article id 108736Article, review/survey (Refereed)
    Abstract [en]

    The presence of microplastics (MPs) is increasing at a dramatic rate globally, posing risks for exposure and subsequent potential adverse effects on human health. Apart from being physical objects, MP particles contain thousands of plastic-associated chemicals (i.e., monomers, chemical additives, and non-intentionally added substances) captured within the polymer matrix. These chemicals are often migrating from MPs and can be found in various environmental matrices and human food chains; increasing the risks for exposure and health effects. In addition to the physical and chemical attributes of MPs, plastic surfaces effectively bind exogenous chemicals, including environmental pollutants (e.g., heavy metals, persistent organic pollutants). Therefore, MPs can act as vectors of environmental pollution across air, drinking water, and food, further amplifying health risks posed by MP exposure. Critically, fragmentation of plastics in the environment increases the risk for interactions with cells, increases the presence of available surfaces to leach plastic-associated chemicals, and adsorb and transfer environmental pollutants. Hence, this review proposes the so-called triple exposure nexus approach to comprehensively map existing knowledge on interconnected health effects of MP particles, plastic-associated chemicals, and environmental pollutants. Based on the available data, there is a large knowledge gap in regard to the interactions and cumulative health effects of the triple exposure nexus. Each component of the triple nexus is known to induce genotoxicity, inflammation, and endocrine disruption, but knowledge about long-term and inter-individual health effects is lacking. Furthermore, MPs are not readily excreted from organisms after ingestion and they have been found accumulated in human blood, cardiac tissue, placenta, etc. Even though the number of studies on MPs-associated health impacts is increasing rapidly, this review underscores that there is a pressing necessity to achieve an integrated assessment of MPs’ effects on human health in order to address existing and future knowledge gaps.

  • 31.
    Alijagic, Andi
    et al.
    Örebro University, School of Science and Technology. Inflammatory Response and Infection Susceptibility Centre (iRiSC), Örebro University, Örebro, Sweden; School of Medical Sciences, Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Särndahl, Eva
    Örebro University, School of Medical Sciences. Inflammatory Response and Infection Susceptibility Centre (iRiSC).
    Can evolutionary immunology decode micro and nanoplastic challenges?2024In: Frontiers in Immunology, E-ISSN 1664-3224, Vol. 15, article id 1404360Article, review/survey (Refereed)
  • 32.
    Alijagic, Andi
    et al.
    Örebro University, School of Science and Technology. School of Medical Sciences Faculty of Medicine and Health, Örebro University, Örebro, Sweden; Inflammatory Response and Infection Susceptibility Centre (iRiSC), Faculty of Medicine and Health, Örebro University, Örebro, Sweden.
    Wang, Xuying
    KTH Royal Institute of Technology, Division of Surface and Corrosion Science, Stockholm, Sweden.
    Vallabani, Naga Vera Srikanth
    Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden.
    Melin, Pelle
    Swerim, Kista, Sweden.
    Särndahl, Eva
    Örebro University, School of Medical Sciences. Inflammatory Response and Infection Susceptibility Centre (iRiSC).
    Karlsson, Hanna L.
    Institute of Environmental Medicine, Karolinska Institute, Stockholm, Sweden.
    Odnevall, Inger
    KTH Royal Institute of Technology, Division of Surface and Corrosion Science, Stockholm, Sweden; AIMES – Center for the Advancement of Integrated Medical and Engineering Sciences at Karolinska Institutet and KTH Royal Institute of Technology, Stockholm, Sweden; Department of Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Characteristics and health risks of the inhalable fraction of metal additive manufacturing powders2024In: Nano Select, E-ISSN 2688-4011, Vol. 5, no 4, article id 2300188Article in journal (Refereed)
    Abstract [en]

    Metal additive manufacturing (AM) is gaining traction but raises worker health concerns due to micron-sized powders, including fine inhalable particles. This study explored particle and surface characteristics, electrochemical properties, metal release in artificial lysosomal fluid (ALF), and potential toxicity of virgin and sieved virgin Fe-based powders, stainless steel (316L), Fe, and two tooling steels. Virgin particles ranged in size from 1 to 100μm, while sieved particles were within the respirable size range (<5–10μm). Surface oxide composition differed from bulk composition. The Fe powder showed low corrosion resistance and high metal release due to a lack of protective surface oxide. Sieved particles of 316L, Fe, and one tooling steel released more metals into ALF than virgin particles, with the opposite was observed for the other tooling steel. Sieved particles had no notable impact on cell viability or micronuclei formation in human bronchial epithelial cells. Inflammatory response in human macrophages was generally low, except for the Fe powder and one tooling steel, which induced increased interleukin-8 (IL-8/CXCL-8) and monocyte chemoattractant protein-1 (MCP-1/CCL-2) secretion. This study underscores distinctions between virgin and sieved Fe-based powders and suggests relatively low acute toxicity.

  • 33.
    Alizadeh Khameneh, Mohammad Amin
    KTH, School of Architecture and the Built Environment (ABE), Urban Planning and Environment, Geodesy and Geoinformatics.
    Tree Detection and Species Identification using LiDAR Data2013Independent thesis Advanced level (degree of Master (Two Years)), 30 credits / 45 HE creditsStudent thesis
    Abstract [en]

    The importance of single-tree-based information for forest management and related industries in countries like Sweden, which is covered in approximately 65% by forest, is the motivation for developing algorithms for tree detection and species identification in this study. Most of the previous studies in this field are carried out based on aerial and spectral images and less attention has been paid on detecting trees and identifying their species using laser points and clustering methods.

    In the first part of this study, two main approaches of clustering (hierarchical and K-means) are compared qualitatively in detecting 3-D ALS points that pertain to individual tree clusters. Further tests are performed on test sites using the supervised k-means algorithm in which the initial clustering points are defined as seed points. These points, which represent the top point of each tree are detected from the cross section analysis of the test area. Comparing those three methods (hierarchical, ordinary K-means and supervised K-means), the supervised K-means approach shows the best result for clustering single tree points. An average accuracy of 90% is achieved in detecting trees. Comparing the result of the thesis algorithms with results from the DPM software, developed by the Visimind Company for analysing LiDAR data, shows more than 85% match in detecting trees.

    Identification of trees is the second issue of this thesis work. For this analysis, 118 trees are extracted as reference trees with three species of spruce, pine and birch, which are the dominating species in Swedish forests. Totally six methods, including best fitted 3-D shapes (cone, sphere and cylinder) based on least squares method, point density, hull ratio and slope changes of tree outer surface are developed for identifying those species. The methods are applied on all extracted reference trees individually. For aggregating the results of all those methods, a fuzzy logic system is used because of its good reputation in combining fuzzy sets with no distinct boundaries. The best-obtained model from the fuzzy system provides 73%, 87% and 71% accuracies in identifying the birch, spruce and pine trees, respectively. The overall obtained accuracy in species categorization of trees is 77%, and this percentage is increased dealing with only coniferous and deciduous types classification. Classifying spruce and pine as coniferous versus birch as deciduous species, yielded to 84% accuracy.

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  • 34. Almeida, Nazare da Silva
    et al.
    Sawakuchi, Henrique Oliveira
    Umeå University, Faculty of Science and Technology, Department of Ecology and Environmental Sciences. Department of Thematic Studies–Environmental Change, Linköping University, Hus Temahuset, Campus Valla, 581 83 Linköping, Sweden.
    Teixeira, C.A.S.
    Bertassoli Jr., D.J.
    Furukawa, L.Y.
    Pelissari, M.
    Sawakuchi, A.O.
    Incubation experiments to constrain the production of methane and carbon dioxide in organic-rich shales of the Permian Irati Formation, Parana Basin2020In: Marine and Petroleum Geology, ISSN 0264-8172, E-ISSN 1873-4073, Vol. 112, article id 104039Article in journal (Refereed)
    Abstract [en]

    The Permian Irati Formation in Brazil hosts organic-rich shales and heavy hydrocarbons suitable for biogenic production of methane (CH4) and carbon dioxide (CO2). In this study, shale samples from the irati Formation were used in laboratory incubation experiments performed under different temperatures (22 degrees C, 50 degrees C, 70 degrees C and 80 degrees C) to evaluate the generation of CH4 and CO2 under thermal conditions compatible with biodegradation in shallow gas systems (< 80 degrees C). Despite our laboratory experiments do not represent natural subsurface temperature conditions, it is observed that the concentrations of CH4 and CO2 increase when shale samples are incubated under temperature higher than 22 degrees C. Samples incubated at 80 degrees C presented a maximum CH4 yield of 2.45 ml/t.d (milliliter per ton of shale per day) compared to 0,49 ml/t.d at 22 degrees C, 1.75 ml/t.d at 50 degrees C and 2.09 ml/t.d at 70 degrees C. The same trend of increasing production rates with higher temperatures was observed for CO2, with maximum potential production observed under a laboratory temperature of 80 degrees C, reaching 23.47 ml/t.d. Stable carbon isotopes (delta C-13) on CH4 and CO2 suggest a mixture of thermogenic and secondary microbial gas. However, the measured CH4 and CO2 can be generated through methanogenic degradation of heavy hydrocarbons present in the studied shales, difficulting the use of carbon isotope composition to discriminate between biogenic and thermogenic gases. The studied shale samples showed significant differences in CH4 and CO2 production rates, which are possibly related to the major elements composition of the mineral matrix. Higher CH4 and CO2 production rates occurred in samples with higher amount of sulfur. Besides sulfur, we highlight that others soluble elements in the mineral matrix, such as Ca and Mg, can play an important role for the generation of biogenic CH4 and CO2. The present work intends to alert for the importance of thermal conditions as well as the geochemical composition of the mineral matrix to build conceptual models about shallow gas systems, acting on organic-rich shales in sedimentary basins.

  • 35.
    Almeida, Nazare da Silva
    et al.
    Univ Sao Paulo, Brazil.
    Sawakuchi, Henrique
    Linköping University, Department of Thematic Studies, Tema Environmental Change. Linköping University, Faculty of Arts and Sciences. Umea Univ, Sweden.
    Teixeira, C. A. S.
    Univ Sao Paulo, Brazil.
    Bertassoli, D. J. Jr.
    Univ Sao Paulo, Brazil.
    Furukawa, L. Y.
    Univ Sao Paulo, Brazil.
    Pelissari, M.
    Univ Sao Paulo, Brazil.
    Sawakuchi, A. O.
    Univ Sao Paulo, Brazil.
    Incubation experiments to constrain the production of methane and carbon dioxide in organic-rich shales of the Permian Irati Formation, Parana Basin2020In: Marine and Petroleum Geology, ISSN 0264-8172, E-ISSN 1873-4073, Vol. 112, article id UNSP 104039Article in journal (Refereed)
    Abstract [en]

    The Permian Irati Formation in Brazil hosts organic-rich shales and heavy hydrocarbons suitable for biogenic production of methane (CH4) and carbon dioxide (CO2). In this study, shale samples from the irati Formation were used in laboratory incubation experiments performed under different temperatures (22 degrees C, 50 degrees C, 70 degrees C and 80 degrees C) to evaluate the generation of CH4 and CO2 under thermal conditions compatible with biodegradation in shallow gas systems (amp;lt; 80 degrees C). Despite our laboratory experiments do not represent natural subsurface temperature conditions, it is observed that the concentrations of CH4 and CO2 increase when shale samples are incubated under temperature higher than 22 degrees C. Samples incubated at 80 degrees C presented a maximum CH4 yield of 2.45 ml/t.d (milliliter per ton of shale per day) compared to 0,49 ml/t.d at 22 degrees C, 1.75 ml/t.d at 50 degrees C and 2.09 ml/t.d at 70 degrees C. The same trend of increasing production rates with higher temperatures was observed for CO2, with maximum potential production observed under a laboratory temperature of 80 degrees C, reaching 23.47 ml/t.d. Stable carbon isotopes (delta C-13) on CH4 and CO2 suggest a mixture of thermogenic and secondary microbial gas. However, the measured CH4 and CO2 can be generated through methanogenic degradation of heavy hydrocarbons present in the studied shales, difficulting the use of carbon isotope composition to discriminate between biogenic and thermogenic gases. The studied shale samples showed significant differences in CH4 and CO2 production rates, which are possibly related to the major elements composition of the mineral matrix. Higher CH4 and CO2 production rates occurred in samples with higher amount of sulfur. Besides sulfur, we highlight that others soluble elements in the mineral matrix, such as Ca and Mg, can play an important role for the generation of biogenic CH4 and CO2. The present work intends to alert for the importance of thermal conditions as well as the geochemical composition of the mineral matrix to build conceptual models about shallow gas systems, acting on organic-rich shales in sedimentary basins.

  • 36.
    Amano, Kazutaka
    et al.
    Department of Geoscience, Joetsu University of Education, Joetsu, Japan.
    Kiel, Steffen
    Swedish Museum of Natural History, Department of Paleobiology.
    Hryniewicz, Krzysztof
    Institute of Paleobiology, Polish Academy of Sciences, Warszawa, Poland.
    Jenkins, Robert
    College of Science and Engineering, Kanazawa University, Kanazawa, Japan.
    Bivalvia in ancient hydrocarbon seeps2022In: Ancient Hydrocarbon Seeps / [ed] Kaim, Andrzej; Landman, Neil H.; Cochran, J. Kirk, Berlin: Springer Berlin/Heidelberg, 2022, p. 267-321Chapter in book (Refereed)
    Abstract [en]

    Bivalves are an important part of the methane seep fauna ever since seeps appeared in the geologic record. The chronostratigraphic ranges of seep-inhabiting chemosymbiotic bivalves show an overall increase in diversity at seeps since the Paleozoic. The most common group at Paleozoic and early Mesozoic seeps are modiomorphids, with a few additional records of solemyids and anomalodesmatans. The most common infaunal chemosymbiotic bivalve taxa at modern seeps, lucinids and thyasirids, appeared at seeps in the Late Jurassic and earliest Cretaceous. They diversified during the Cretaceous synchronous with the peak of the “Mesozoic Marine Revolution” and first occurrences of gastropod predatory drill holes in the shells of seep-inhabiting bivalves, soon after the appearance of these gastropods in the mid-Cretaceous. The two dominant bivalve clades of the modern vent and seep fauna, bathymodiolins and vesicomyids, appeared in the Eocene. Their origin has been linked to a deep-water extinction event at the Paleocene-Eocene Thermal Maximum. However, the fossil record of chemosymbiotic bivalves at seeps during this time interval does not display any extinction. Rather, the mid-Eocene appearance of semi-infaunal and epifaunal bivalves such as bathymodiolins and vesicomyids might be linked to a dramatic rise in seawater sulfate concentrations at this time.

  • 37.
    Amin, Hadi
    et al.
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    Sjöberg, Lars
    Division of Geodesy and satellite positioning, KTH.
    Bagherbandi, Mohammad
    University of Gävle, Faculty of Engineering and Sustainable Development, Department of Computer and Geospatial Sciences, Geospatial Sciences.
    A global vertical datum defined by the conventional geoid potential and the Earth ellipsoid parameters2019In: Journal of Geodesy, ISSN 0949-7714, E-ISSN 1432-1394, Vol. 93, no 10, p. 1943-1961Article in journal (Refereed)
    Abstract [en]

    The geoid, according to the classical Gauss–Listing definition, is, among infinite equipotential surfaces of the Earth’s gravity field, the equipotential surface that in a least squares sense best fits the undisturbed mean sea level. This equipotential surface, except for its zero-degree harmonic, can be characterized using the Earth’s global gravity models (GGM). Although, nowadays, satellite altimetry technique provides the absolute geoid height over oceans that can be used to calibrate the unknown zero-degree harmonic of the gravimetric geoid models, this technique cannot be utilized to estimate the geometric parameters of the mean Earth ellipsoid (MEE). The main objective of this study is to perform a joint estimation of W0, which defines the zero datum of vertical coordinates, and the MEE parameters relying on a new approach and on the newest gravity field, mean sea surface and mean dynamic topography models. As our approach utilizes both satellite altimetry observations and a GGM model, we consider different aspects of the input data to evaluate the sensitivity of our estimations to the input data. Unlike previous studies, our results show that it is not sufficient to use only the satellite-component of a quasi-stationary GGM to estimate W0. In addition, our results confirm a high sensitivity of the applied approach to the altimetry-based geoid heights, i.e., mean sea surface and mean dynamic topography models. Moreover, as W0 should be considered a quasi-stationary parameter, we quantify the effect of time-dependent Earth’s gravity field changes as well as the time-dependent sea level changes on the estimation of W0. Our computations resulted in the geoid potential W0 = 62636848.102 ± 0.004 m2 s−2 and the semi-major and minor axes of the MEE, a = 6378137.678 ± 0.0003 m and b = 6356752.964 ± 0.0005 m, which are 0.678 and 0.650 m larger than those axes of GRS80 reference ellipsoid, respectively. Moreover, a new estimation for the geocentric gravitational constant was obtained as GM = (398600460.55 ± 0.03) × 106 m3 s−2.

  • 38.
    Amirian, Parissa
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Civil and Industrial Engineering.
    Volunteering at an eco-community: The impact on the three basic psychological needs - a case study of Hästekasen Farm2021Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
  • 39.
    Andermann, Tobias
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Biology, Department of Organismal Biology, Systematic Biology. Uppsala University, Science for Life Laboratory, SciLifeLab. Univ Gothenburg, Dept Biol & Environm Sci, Gothenburg, Sweden.;Univ Gothenburg, Gothenburg Global Biodivers Ctr, Dept Biol & Environm Sci, Gothenburg, Sweden..
    Stromberg, Caroline A. E.
    Univ Washington, Dept Biol, Seattle, WA 98195 USA.;Univ Washington, Burke Museum Nat Hist & Culture, Seattle, WA 98195 USA..
    Antonelli, Alexandre
    Univ Gothenburg, Dept Biol & Environm Sci, Gothenburg, Sweden.;Univ Gothenburg, Gothenburg Global Biodivers Ctr, Dept Biol & Environm Sci, Gothenburg, Sweden.;Univ Oxford, Dept Plant Sci, Oxford, England.;Royal Bot Gardens, Richmond, Surrey, England..
    Silvestro, Daniele
    Univ Gothenburg, Dept Biol & Environm Sci, Gothenburg, Sweden.;Univ Gothenburg, Gothenburg Global Biodivers Ctr, Dept Biol & Environm Sci, Gothenburg, Sweden.;Univ Fribourg, Dept Biol, Fribourg, Switzerland.;Swiss Inst Bioinformat, Fribourg, Switzerland..
    The origin and evolution of open habitats in North America inferred by Bayesian deep learning models2022In: Nature Communications, E-ISSN 2041-1723, Vol. 13, no 1, article id 4833Article in journal (Refereed)
    Abstract [en]

    Some of the most extensive terrestrial biomes today consist of open vegetation, including temperate grasslands and tropical savannas. These biomes originated relatively recently in Earth's history, likely replacing forested habitats in the second half of the Cenozoic. However, the timing of their origination and expansion remains disputed. Here, we present a Bayesian deep learning model that utilizes information from fossil evidence, geologic models, and paleoclimatic proxies to reconstruct paleovegetation, placing the emergence of open habitats in North America at around 23 million years ago. By the time of the onset of theQuaternary glacial cycles, open habitatswere coveringmore than 30% of North America and were expanding at peak rates, to eventually become the most prominent natural vegetation type today. Our entirely datadriven approach demonstrates how deep learning can harness unexplored signals fromcomplex data sets to provide insights into the evolution of Earth's biomes in time and space.

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  • 40.
    Anderson, Heidi
    et al.
    Dorrigo, NSW, Australia.
    David J. Batten, David
    Manchester University.
    Cantrill, David
    National Herbarium of Victoria, Royal Botanic Gardens Melbourne.
    Cleal, Christopher
    Museum of Wales.
    Susanne Feist-Burkhardt, Susanne
    SFB Geological Consulting & Services, Odenwaldstrasse 18, D-64372 Ober-Ramstadt, Germany.
    Fensome, Robert
    Natural Resources Canada.
    Head, Martin
    Brock University, Canada.
    Herendeen, Patrick
    Chicago Botanuic Garden.
    Jaramillo, Carlos
    Smithsonian Institution.
    Kvaček, Jiří
    Czech National Museum, Prague.
    McLoughlin, Stephen
    Swedish Museum of Natural History, Department of Paleobiology.
    Skog, Judith
    George Mason University.
    Takahashi, Masamichi
    Niigata University.
    Wicander, Reed
    Department of Earth and Atmospheric Sciences, Central Michigan University .
    (087–090) Proposal to treat the use of a hyphen in the name of a fossil-genus as an orthographical error2015In: Taxon, ISSN 0040-0262, E-ISSN 1996-8175Article in journal (Refereed)
    Abstract [en]

    We propose modifications to the Code such that use of a hyphen in the name of a fossil-genus is treated as an error to be corrected by deletion of the hyphen. This will circumvent the need to conserve the numerous de-hyphenated names against unused hyphenated forms. We propose changes to Art. 60 of the Code to allow this correction, and the addition of a phrase in Art. 20 to add clarity to the naming of fossil-genera.

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  • 41.
    Anderson, Lakin
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Measuring Sustainable Cities: An approach for assessing municipal-level sustainability indicator systems in Sweden2013Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    It is now common for managers, strategists, planners and citizens at municipality level to use sustainable development indicators (SDI) to help them work towards sustainable development. SDI constitute an information system for monitoring, reporting and decision-making which in theory should help us decide how to intervene in natural, economic, social and political systems for a better, more sustainable future. But not all indicator systems are created equal. Some are better tools than others when it comes to helping cities and municipalities in their work, and thousands of municipalities use SDI worldwide. How then should we assess the effectiveness of existing indicators for municipalities?

    To answer this question I develop an approach for assessing the edesign, creation and communication of existing, in-use SDI, and then apply it in a case study in Falun Municipality in Dalarna County, Sweden. The approach assesses five aspects of SDI: ‘Vision’, ‘Framework’, ‘Indicator Selection’, ‘Stakeholder Participation’ and ‘Communication’. The findings in Falun suggest that SDI have been essential to the implementation of sustainable development in policy and action in general municipal operations, but the municipality has not moved beyond a ‘conventional’ sustainable development vision and monitoring strategy. The benefits and constraints of the current indicator system are then discussed using the above approach, and the thesis finishes by offering suggestions for the municipality going forward. I also point to the need to develop a standardised assessment method for thousands of municipalities using indicator systems used today, to help in ongoing review and improvement of SDI in practice.

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    Measuring Sustainable Cities: An approach for assessing municipal-level sustainability indicator systems in Sweden
  • 42. Anderson, Lloyd B.
    et al.
    Hönisch, Bärbel
    Coxall, Helen K.
    Stockholm University, Faculty of Science, Department of Geological Sciences. Stockholm University, Faculty of Science, The Bolin Centre for Climate Research (together with KTH & SMHI).
    Bolge, Louise
    Atmospheric CO2 Estimates for the Late Oligocene and Early Miocene Using Multi-Species Cross-Calibrations of Boron Isotopes2024In: Paleoceanography and Paleoclimatology, ISSN 2572-4517, E-ISSN 2572-4525, Vol. 39, no 1, article id e2022PA004569Article in journal (Refereed)
    Abstract [en]

    The boron isotope (δ11B) proxy for seawater pH is a tried and tested means to reconstruct atmospheric CO2 in the geologic past, but uncertainty remains over how to treat species-specific calibrations that link foraminiferal δ11B to pH estimates prior to 22 My. In addition, no δ11B-based reconstructions of atmospheric CO2 exist for wide swaths of the Oligocene (33–23 Ma), and large variability in CO2 reconstructions during this epoch based on other proxy evidence leaves climate evolution during this period relatively unconstrained. To add to our understanding of Oligocene and early Miocene climate, we generated new atmospheric CO2 estimates from new δ11B data from fossil shells of surface-dwelling planktic foraminifera from the mid-Oligocene to early Miocene (∼28–18 Ma). We estimate atmospheric CO2 of ∼680 ppm for the mid-Oligocene, which then evolves to fluctuate between ∼500–570 ppm during the late Oligocene and between ∼420–700 ppm in the early Miocene. These estimates tend to trend higher than Oligo-Miocene CO2 estimates from other proxies, although we observe good proxy agreement in the late Oligocene. Reconstructions of CO2 fall lower than estimates from paleoclimate model simulations in the early Miocene and mid Oligocene, which indicates that more proxy and/or model refinement is needed for these periods. Our species cross-calibrations, assessing δ11B, Mg/Ca, δ18O, and δ13C, are able to pinpoint and evaluate small differences in the geochemistry of surface-dwelling planktic foraminifera, lending confidence to paleoceanographers applying this approach even further back in time.

  • 43.
    Andersson, Anna
    et al.
    Kristianstad University, Faculty of Natural Science.
    Andersson, Sanna
    Kristianstad University, Faculty of Natural Science.
    Aluntillverkningens betydelse för skogen: med ett exempel från Andrarums alunbruk i Skåne 1637–19122020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Andrarums alummill left a great impression in the surrounding forest. The mill required large resources of wood to be able to process alum slate to alum, which meant that the need for wood resources was big. The area around the alummill was given a mark in the terrain in 1730, with 21 large stones placed along the circular periphery, which is called Verkalinjen. The purpose of the study is to investigate the importance of alum production for the forest inside the Verkalinjen. The focus of the thesis was to study the importance of wood consumption during the years when the mill was active. In addition to a general study for the entire area within the Verkalinjen, the study was delimited to the properties Breabäck, Snärpe, Rugeröd and Nybygget. The method and materials used in the essay are studies of historical map material and analysis of documents belonging to the archive at Christinehof. Maps were rectified and digitized in GIS-ArcMap, inside the Verkalinjen and in the selected research area. The result shows that the forest in the study area has decreased greatly between 1684 and 1704, from having been a forest area, to been transformed into a sparse and thin beech forest. The use of the forest has changed over time and the results show that there was a forest shortage in the study area during the 18th century. In the middle of the 17th century, it is believed that the forest in the Andrarums alummill district will never meet the needs of the mill in the long term and it will be difficult for the forest to recover. Replanting, housekeeping and grazing ban take effect, but despite this, an open and woodless landscape emerges during the 18th century, with elements of small islands of forest. The result also shows that the forest has recovered in the early 1900s and there is then a great variety of trees in the area, with both deciduous and coniferous forests.

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  • 44.
    Andersson, Annie
    et al.
    Kristianstad University, Faculty of Natural Science.
    Habainy, Rana
    Kristianstad University, Faculty of Natural Science.
    Friluftsliv i Östra Göinge: en undersökning om attityd och natur i Östra Göinge kommun2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis focuses on the attitude between nature and the residents of Östra Göinge municipality. The purpose of this research and thesis is to provide a clearer picture of the resident’s outdoor life and relationship to nature within the municipality. In addition, this research considered possible development opportunities in the outdoor life category within the community while also addressing the question of accessibility to green areas. This research used an online survey, distributed on Facebook, to groups linked to Östra Göinge. The results from the survey show that even though the residents of the community are satisfied with the access to green areas in the municipality, they still see development opportunities which will help promote outdoor life in Östra Göinge.

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  • 45.
    Andersson, Erik
    et al.
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Enqvist, Johan
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Tengö, Maria
    Stockholm University, Faculty of Science, Stockholm Resilience Centre.
    Stewardship in Urban Landscapes2017In: The Science and Practice of Landscape Stewardship / [ed] Claudia Bieling, Tobias Plieninger, Cambridge University Press, 2017, p. 219-221Chapter in book (Refereed)
  • 46.
    Andersson, Hanna
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences.
    Bradoriids from the middle Cambrian 'thin' Stephen Formation at Odaray Mountain, Canadian Rocky Mountains2014Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Two new species of Cambrian bradoriid arthropods have been found in the ‘thin’ Stephen Formation, Odaray Mountain, Canada; the hipponicharionid Flumenoglacies michaeli n. sp. and the comptalutid Phasoia stephenensis n. sp. This paper includes the description and illustrations of these species as well as two undetermined species from the same locality. Phasoia stephenensis n. sp. is the first Phasoia reported from Laurentia and Flumenoglacies michaeli n. sp. belongs to the new genus Flumenoglacies recently described by Peel & Streng (in press) from Greenland.

    In the discussion previous reports of the genus Phasoia are ordered chronologically and a migration path from Gondwana to Laurentia is suggested. However, more information on the stratigraphic and regional distribution of this taxon is needed to support this theory since Phasoia is so far only known from Australia, South China and now North America.

    The ornamentation of Phasoia stephenensis n. sp. and Flumenoglacies michaeli n. sp. is discussed and compared with the ornamentation of the hipponicharion Pseudobeyrichona longquanxiensis (Cui 1987), the svealutid Tsunyiella Zhang (1974) and the cambriid Petrianna fulmenata Siveter (1995). It is suggested that it might be remnants of a respiratory system. 

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  • 47. Andersson, Hans
    et al.
    Widgren, MatsStockholm University, Faculty of Social Sciences, Department of Human Geography.
    Kan man leva på en ödegård? Huvudgårdar, landbotorp och odlingssystem under medeltid i Lägerbobygden, Östergötland2016Collection (editor) (Refereed)
    Abstract [en]

    Is it possible to survive on a deserted farm: Manors, tenants and farming systems during the Middle Ages in the Lägerbo area, Östergötland. 

    This study approaches the late medieval farm desertion from a landscape perspective. It focuses on the area of a former medieval estate in southern Östergötland, Sweden. Based on a retrogressive analysis of cadastral maps and historical records the medieval settlement is reconstructed. In this process three formerly unknown deserted farms were identified, with abandoned field systems and building remains.  The volume provides the archaeological documentation of field systems and settlements at these sites. These data provide the background for investigating the shifting social and ecological circumstances that once made it possible for tenant families to survive on these farms. During the height of the manorial system the small farms were specialised units in a redistributive system. In the late 14th century the estate and all tenant farms were donated to the convents of Vadstena and Vreta.  Rents were no longer paid in labour but in butter.  In the fifteenth century several farms were abandoned and turned into meadows under the surviving farms. The new tenurial relations prevented the recolonization of the farms. The study is the result of an interdisciplinary project involving medieval archaeology, historical geography, palynology and medieval history.

  • 48. Andersson, Jan-Olov
    et al.
    Hasselid, Sara
    Widen, Per
    Bax, Gerhard
    Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences. Uppsala University, Teknisk-naturvetenskapliga vetenskapsområdet, Earth Sciences, Department of Earth Sciences, Environment and Landscape Dynamics. ELD.
    Is the Snow Leopard (Unica unica) endangered?: A study of popular viability and distribution using vulnerability and GIS analysis methods2004In: Proceedings of the 7th International Symposium on High Mountain Remote Sensing Cartography, 2004, p. 224-Conference paper (Refereed)
  • 49.
    Andersson, Linnea
    Uppsala University, Disciplinary Domain of Science and Technology, Earth Sciences, Department of Earth Sciences, LUVAL.
    Kartläggning av möjligheten att återanvända takdagvatten för att minska dricksvattenförbrukningen2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Drinking water is vital for our daily life. With climate change comes increasing temperatures and more extreme weather which can jeopardize our access to drinking water. One way to reduce our drinking water consumption is to collect rainwater and use it for processes which have lower quality demands than drinking water. Swedavia is constantly working on making their airports more environmentally friendly and as a part of this reducing the drinking water consumption. This project examines how water can be collected at Swedavia’s airports. The project results should be of intent to all of Swedavia’s airports even if the project is performed at Stockholm Arlanda Airport.

    In this project the water quality from five different types roofs has been studied. The different kind of roofs were chosen based on previous studies where pollutants in roof-harvested rainwater were studied. Other aspects such as location on the airports were also considered. Samplings were collected at two different occasions where water was collected from the different roofs. One sample of clean rainwater was collected as a reference. Five nutrients, dissolved organic matter, suspended matter and six heavy metals were analyzed.

    Three of the roofs gave water with high values that exceeded the quality limits. The samples from the green roof showed high levels of phosphorus and dissolved organic matter. The steel roof gave high levels of zink which may origin from its zink coating. The roof with PVC plastic also gave high levels of zink, but not as high as the steel roof. The roof with FPO plastic, a more environmentally friendly plastic, and the roof with roof paper gave low values and did not exceed any quality limits. The reference sample of clean rainwater gave high values of suspended matter at the second occasion and high values of lead that exceeded the quality limits.

    The conclusions of this project are that roof-harvested rainwater from green roofs, steel roofs and roofs with PVC plastic may exceed quality limits which makes them less suitable for collecting and re-use. The results are based on the two sampling occasions which means that sampling at more occations needs to be done to make definitive conclusions. The roofs with FPO plastic and roof paper do not exceed any quality limits and can therefore, according to the analyzed parameters, be suitable for collecting rainwater. It is important to note that to be able to reuse the water and guarantee that the quality of the water does not exceed any quality limits more parameters should be analyzed.

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  • 50.
    Andersson, Sofia
    et al.
    Kristianstad University, School of Education and Environment.
    Mhamutovic, Naida
    Kristianstad University, School of Education and Environment.
    Skyddszoner som fosforfällor: En studie om skyddszonernas förmåga att förhindra fosforläckage2015Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Phosphorus leaking from our fertilized arable land contributes to eutrophication of lakes and seas and travels among other things, with particles from fertilized soil. Straightening of rivers and ditching helps drained water travel quickly from the arable land lakes and seas. To avoid phosphorus leaking there are buffer zones that are placed between the field and the streams with the purpose of captivating the phosphorus. One previous study has shown that a risk occurs for phosphorus saturation on the lands adjacent to the streams (Borggaard, Moberg & Sibbesen 1991; Vought et al 1994; Svanbäck et al 2013).   

      

    This thesis aims to see if today’s buffer zones are saturated or can take up more phosphorus and if the difference in the type of soil matter to the result. The effects of pH and organic matter on the phosphorus content are also examined. The soils clay, moraine  and sand are studied in this thesis. The work also aims to demonstrate the changes in the landscape and history of the buffer zones.  

      

    Soil samples were collected from 15 buffer zones around Kristianstad. The samples were dried, sieved and then shaken with water containing a known amount of phosphorus. Uptake of phosphorus was then measured. Historical and contemporary maps were also studied to see the landscape change.  

      

    The analysis showed that nine out of fifteen zones were saturate. The three soil types each had three saturated zones and two unsaturated and the difference was not significant between the soil types. For the soil clay results showed that pH and organic matter content influenced the amount of phosphorus in which, a higher pH, showed a higher phosphorus content and the higher organic matter reviled a lower amount if phosphorus. For moraine results showed same as in clay but the relation between the organic matter and how it affected the phosphorus content was not significant. The result for the sand was that higher pH in the soil resulted to higher phosphorus content. The same effect was seen for the organic matter in sand which means that the phosphorus content rises with higher organic matter.   

    The buffer zones that we studied occur mostly on land that has been used as arable land for at least 100 years, while others have previously been used as wet- or other meadows or pastures. The areas that have been arable lands a long time have probably been fertilized heavily during the postwar period. Establishing buffer zones may therefore have contributed to recreate the landscape as it was before the rationalization of agriculture in the late 1950s. Buffer zones prevent erosion and help to preserve biodiversity both in the stream and buffer zone. Today's eligible zones may only be grassed but one could imagine future protection zones with salix / tree where the phosphorus is removed through the wood.  

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