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  • 1.
    Acikkol, Naz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Testing the Cretaceous Diversity of Ichthyosaurs and Their Extinction Hypotheses Using a Quantitative Approach2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    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.

  • 2.
    Adamsson, Karolin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Kollektivtrafikknutpunkter i Göteborg ur ett genusperspektiv2017Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    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.

  • 3.
    Ahlgren, Joakim
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för fysikalisk och analytisk kemi, Analytisk kemi. Institutionen för biokemi och organisk kemi, Organisk kemi I. Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Limnologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för fysikalisk och analytisk kemi.
    Reitzel, Kasper
    Danielsson, Rolf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för fysikalisk och analytisk kemi, Analytisk kemi. Institutionen för biokemi och organisk kemi, Organisk kemi I. Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Limnologi. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för fysikalisk och analytisk kemi.
    Gogoll, Adolf
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för fysikalisk och analytisk kemi, Analytisk kemi. Institutionen för biokemi och organisk kemi, Organisk kemi I. Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Limnologi.
    Rydin, Emil
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Kemiska sektionen, Institutionen för fysikalisk och analytisk kemi, Analytisk kemi. Institutionen för biokemi och organisk kemi, Organisk kemi I. Teknisk-naturvetenskapliga fakulteten, Biologiska sektionen, Institutionen för ekologi och evolution, Limnologi.
    Biogenic phosphorus in oligotropic mountain lake sediments: Differences in composition measured with NMR spectroscopy2006Inngår i: Water Research, nr 40, 3705-3712 s.Artikkel i tidsskrift (Fagfellevurdert)
  • 4.
    Ahlgren, Sara
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Changes in size distribution of lakes in the Nadym catchment, northern Russia2012Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    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.

  • 5.
    Ahlqvist, Ola
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi och kvartärgeologi (INK).
    Context Sensitive Transformation of Geographic Information2000Doktoravhandling, monografi (Annet vitenskapelig)
    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.

  • 6.
    Akrawi, Narin
    et al.
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik.
    Ciechowicz, Michelle
    Södertörns högskola, Institutionen för naturvetenskap, miljö och teknik.
    Fotbollsturism: En studie om fotbollsturisters upplevelse och tillfredställelse2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Denna studie utförs av två studenter för deras examensarbete i Turismvetenskap vid Södertörns högskola, Sverige. I studien undersöks huruvida de påvisade karaktäristiska dragen för en sportturist stämmer överens med verkligheten. I studien undersöks även vilka faktorer fotbollsturisten anser viktiga för uppnå en tillfredsställande upplevelse under en fotbollsresa. Ämnet är viktigt att belysa för främjandet av turismnäringen när det kommer till resor för sportsliga syften. Genom identifieringen av specifika element inom fenomenet ökar kunskapen och utvecklingen av sportturism. Metoden som användes för att undersöka problematiken kring fenomenet i denna studie utfördes av intervjuer med tjugo potentiella respondenter. Dessa respondenten utgörs av individer som reste till Lissabon, Portugal för att delta i kvartsfinalen i Champions League mellan SL Benfica och FC Bayern München den 13 april 2016. Intervjuerna tog plats i München, Tyskland och Lissabon, Portugal. Respondenterna gav värdefullt bidrag genom åsikter, känslor och erfarenheter från tidigare sportresor. Det material som samlades in av intervjuerna sammanfogades sedan med tidigare forskning och teorier inom forskningsområde för att på så sätt undersöka och identifiera fenomenet. Resultatet i studien visar att trots de karaktäristiska dragen för en sportturist som påvisats av bland annat teoretikerna Harrison-Hill & Chalip (2005) stämmer inte överens eller stämmer delvis med respondenterna i studien. Trots detta går det att uppnå en tillfredsställande upplevelse genom att de faktorer som sportturisten anser vara viktiga för att uppnå en tillfredställande upplevelse. Faktorer som identifierats som tillfredsställande gentemot respondenternas behov och begär i denna studie, utgörs av bland annat: bra väder, bra sittplatser, en bra match, att laget vinner, säkerhet, transport, bra sällskap, att allting går smidigt, en bra resa, bra priser, bra atmosfär, att det ska finnas öl, att vara på plats i tid, att stå på rätt sida av planen tillsammans med andra supportar, att det inte förekommer brister i kommunikationen samt bra boende/ hotell och restauranger. På så sätt uppnås positiva, tillfredsställande och minnesrika resor. De karaktäristiska dragen som påståtts identifiera en sportturist, stämde delvis överens med verkligheten. Verkligheten i studien baseras på respondenternas svar vid intervjutillfällena. De karaktäristiska dragen (baserade på teorierna i studien och de som uppkommit genom respondenternas svar under intervjuerna) av en sportturist och faktorerna för att uppnå en tillfredsställande upplevelse går hand i hand. En tillfredsställande upplevelse för sportturisten utgörs till stor del av de specifika faktorer som identifierats i studien som påverkar fotbollsmatchen som turisten reser dit för.

  • 7.
    Aleklett, Kjell
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Globala energisystem.
    Höök, Mikael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Globala energisystem. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Naturresurser och hållbar utveckling.
    Jakobsson, Kristofer
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Globala energisystem.
    Lardelli, Michael
    School of Molecular and Biomedical Science, University of Adelaide, Australia.
    Snowden, Simon
    Management School, University of Liverpool, United Kingdom.
    Söderbergh, Bengt
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Fysiska sektionen, Institutionen för fysik och astronomi, Globala energisystem.
    The Peak of the Oil Age: Analyzing the world oil production Reference Scenario in World Energy Outlook 20082010Inngår i: Energy Policy, ISSN 0301-4215, Vol. 38, nr 3, 1398-1414 s.Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 8.
    Alexander, Mannelqvist
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Paleontology and Sedimentology of the Alum Shale Formation at Björnberget, Västerbotten County, Sweden2016Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    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.

  • 9.
    Alizadeh Khameneh, Mohammad Amin
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Tree Detection and Species Identification using LiDAR Data2013Independent thesis Advanced level (degree of Master (Two Years)), 30 poäng / 45 hpOppgave
    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.

  • 10.
    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
    Naturhistoriska riksmuseet, Enheten för paleobiologi.
    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 error2015Inngår i: Taxon, ISSN 0040-0262, E-ISSN 1996-8175Artikkel i tidsskrift (Fagfellevurdert)
    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.

  • 11.
    Anderson, Lakin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Measuring Sustainable Cities: An approach for assessing municipal-level sustainability indicator systems in Sweden2013Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    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.

  • 12.
    Andersson, Erik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Enqvist, Johan
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Tengö, Maria
    Stockholms universitet, Naturvetenskapliga fakulteten, Stockholm Resilience Centre.
    Stewardship in Urban Landscapes2017Inngår i: The Science and Practice of Landscape Stewardship / [ed] Claudia Bieling, Tobias Plieninger, Cambridge University Press, 2017, 219-221 s.Kapittel i bok, del av antologi (Fagfellevurdert)
  • 13.
    Andersson, Hanna
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Bradoriids from the middle Cambrian 'thin' Stephen Formation at Odaray Mountain, Canadian Rocky Mountains.2014Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    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. 

  • 14. Andersson, Hans
    et al.
    Widgren, MatsStockholms universitet, Samhällsvetenskapliga fakulteten, Kulturgeografiska institutionen.
    Kan man leva på en ödegård? Huvudgårdar, landbotorp och odlingssystem under medeltid i Lägerbobygden, Östergötland2016Collection/Antologi (Fagfellevurdert)
    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.

  • 15. Andersson, Jan-Olov
    et al.
    Hasselid, Sara
    Widen, Per
    Bax, Gerhard
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Miljö- och landskapsdynamik. ELD.
    Is the Snow Leopard (Unica unica) endangered?: A study of popular viability and distribution using vulnerability and GIS analysis methods2004Inngår i: Proceedings of the 7th International Symposium on High Mountain Remote Sensing Cartography, 2004, 224- s.Konferansepaper (Fagfellevurdert)
  • 16.
    Andersson, Sofia
    et al.
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Mhamutovic, Naida
    Högskolan Kristianstad, Sektionen för lärande och miljö.
    Skyddszoner som fosforfällor: En studie om skyddszonernas förmåga att förhindra fosforläckage2015Independent thesis Basic level (degree of Bachelor), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Fosforläckage från våra gödslade åkermarker bidrar till övergödning i sjöar och hav. Fosforn transporteras ofta via ytavrining till uträtade vattendrag och vattnet färdas snabbt till sjöar och hav. För att undvika fosforläckage anläggs stödberättigade vallbeklädda skyddszoner mellan åker och vattendrag med syftet att ta upp fosfor. Tidigare studier har visat att det kan finnas en risk för fosformättnad i markerna längs vattendragen (Borggaard, Moberg & Sibbesen 1991; Vought, Dahl, Pedersen & Lacousière 1994; Svanbäck, Ulén, Etana, Bergström, Kleinman & Mattsson 2013).   

    Detta examensarbete syftar till att se om dagens skyddszoner är mättade eller kan ta upp mer fosfor och om jordarten spelar någon roll för fosforupptaget. Påverkan av pH och mullhalt på fosforupptaget är något som också undersökts. Jordarterna lera, morän och sand undersöktes i denna studie. Arbetet syftar även till att visa på landskapsförändringar och historik kring skyddszoner. Jordprov samlades in från 15 skyddszoner i Kristianstad. Proven torkades, siktades och skakades sedan med vatten som innehöll en känd mängd fosfor och upptaget av fosforn mättes. Historiska och nutida kartmaterial studerades för att se landskapets förändringar.  

      

    Analyser visade att nio av 15 skyddszoner var mättade med fosfor, d v s uppmätta halter efter skakningen var högre än den tillsatta mängden. De tre jordarterna hade vardera tre mättade skyddszoner och två omättade. Där var ingen statistiskt signifikant skillnad mellan de tre jordarterna med avseende på mättnad. För jordarten lera visade resultatet att pH-värde och mullhalt påverkade innehållet av fosfor där ett högre pH-värde visade en högre fosforhalt och ju högre mullhalten var desto mindre var fosforhalten. För morän visade resultatet samma som för lera men resultatet för hur mullhalten påverkade fosforhalten var inte signifikant. Resultatet för sand var att ju högre pH-värde desto högre var fosforhalten och ju högre mullhalt desto högre fosforhalt.  

    Skyddszonerna finns till största delen på mark som varit åkermark i minst 100 år medan andra tidigare nyttjats som översilningsängar eller som andra ängs- eller betesmarker. De områden som varit åker en längre tid har förmodligen gödslats kraftigt under efterkrigstiden. Anläggningen av skyddszoner kan därför ha bidragit till att återskapa landskapet som det såg ut innan rationaliseringen av jordbruket i slutet av 1950-talet.   

    Skyddszonerna är en viktig del i landskapet de då skyddar vattendragen från ytavvrining, förhindrar erosion och bidrar till att bevara biologisk mångfald i vattendraget och genom att fungera som spridningskorridorer. Våra studier visar att skyddszonerna behöver skötas om de ska fungera som näringfälla. Dagens stödberättigade skyddszoner får endast vara gräsbevuxna men man skulle kunna tänka sig framtida skyddszoner med energiskog eller träd där fosforn förs bort via ved.

  • 17.
    Andersson, Tonny
    Karlstads universitet, Fakulteten för hälsa, natur- och teknikvetenskap (from 2013), Institutionen för miljö- och livsvetenskaper.
    Öppna JavaScript-bibliotek för webbkartor i kommunal tjänst: En jämförelse mellan OpenLayers 3 och Leaflet2015Independent thesis Basic level (university diploma), 10 poäng / 15 hpOppgave
    Abstract [sv]

    Användningen av webbaserade kartapplikationer ökar konstant. I synnerhet märks en ökning av mobil användning av sådana applikationer. Karlstads kommun ser ett ökat antal mobila användare av den egna webbkartan, och vill av den anledningen anpassa webbkartan för att förbättra upplevelsen för mobila användare. Kommunen avser ersätta tekniken bakom den nuvarande webbkartan med modernare alternativ. Valet står mellan två olika öppna JavaScript-baserade API:er för kartapplikationer på webben – OpenLayers 3 och Leaflet.I detta examensarbete jämförs OpenLayers 3 och Leaflet med avseende på kompatibilitet, funktionalitet och prestanda. Kompatibilitet och funktionalitet analyseras huvudsakligen genom studier av tillgänglig dokumentation och bedöms utifrån de krav och önskemål Karlstads kommun framfört. Kraven baseras på kompatibilitet med kommunens befintliga system, samt funktionalitet som minst motsvarar kommunens nuvarande webbkarta.Prestanda testas för utvalda funktioner för WMS- och WFS-tjänster, samt rendering av vektordata från fil. Därtill undersöks även prestandaskillnader mellan OpenLayers 3 och Leaflet i olika webbläsare. Prestandatesterna utförs i testmiljöer i form av enkla kartapplikationer. De utvalda funktionerna testas med enkla skriptmetoder för tidtagning, tillsammans med Firebug, ett insticksprogram till webbläsaren Firefox.Resultatet visar att både OpenLayers 3 och Leaflet uppfyller alla krav på kompatibilitet, även om Leaflet saknar uttryckligt stöd för vissa format. Vidare uppvisar OpenLayers 3 ett bredare inbyggt funktionalitetsstöd. Leaflet är mer begränsat i sitt grundutförande, men kan byggas ut med hjälp av olika insticksprogram för att uppnå samma funktionalitetsnivå som OpenLayers 3.Resultaten av prestandatesterna visar konsekvent att OpenLayers 3 är snabbare än Leaflet. Resultatet blir särskilt tydligt vid hantering av vektordata, där Leaflet är påtagligt långsammare. Trots klara och mätbara skillnader är däremot inte den upplevda skillnaden alltid lika uppenbar. Av den anledningen förespråkas praktiska användartester vid fortsatta studier.Sammanfattningsvis rekommenderas OpenLayers 3 för större applikationer med bredare funktionalitet. Leaflet framhålls dock som ett smidigt alternativ för enklare applikationer.

  • 18.
    Andersson-Sköld, Yvonne
    et al.
    Swedish Geotechnical Institute .
    Bergman, Ramona
    Swedish Geotechnical Institute .
    Nyberg, Lars
    Karlstads universitet.
    Johansson, Magnus
    Karlstads universitet.
    Persson, Erik
    Karlstads universitet.
    Effekter av samhällets säkerhetsåtgärder (ESS): en kartering av arbetet idag med fokus på översvämningar, ras och skred2012Rapport (Annet vitenskapelig)
    Abstract [en]

    I denna rapport redovisas det arbete som pågått inom ESS-programmets första fas inom temaområde naturolyckor. Detta temaområde innefattar skred, ras, erosion och översvämningar. Målet med det arbete som presenteras i denna rapport har varit att skapa en överblick över hurman idag arbetar med dessa frågor i Sverige med fokus på kommunal nivå. Arbetet utgörs aven sammanställning av tidigare studier, beskrivning av metoder samt intervjuer med svenska och norska kommuner och myndigheter. I de svenska kommunerna har politiker och tjänstemän intervjuats.

    Förebyggande åtgärder för att minska sannolikheten för, eller konsekvensen av, olyckor vidtas ofta. Åtgärderna är baserade på en analys eller akut reaktion på en specifik händelse. Vissa åtgärder är platsspecifika och kan vara både fysiska och icke fysiska. Andra åtgärder är mer generella såsom lagstiftning och utbildningsinsatser, regional, nationell och internationell policy, direktiv och ramverk.

  • 19.
    Anna, Sporre
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för ekologi och genetik.
    Utvärdering av grumlighet i miljökontrollprogram för ytvatten vid konstruktionsarbeten2015Independent thesis Advanced level (professional degree), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Vid miljöövervakning av konstruktionsprojekt såsom byggnation av väg och järnväg är det vanligt att uppsatta riktvärden för grumlighet överskrids. I en genomgång av årsrapporter från infrastrukturprojektet BanaVäg i Väst visade det sig att riktvärden för grumlighet ofta sätts upp utan noggrann kartläggning av vattendragens naturliga grumlighetsnivåer. Detta arbetssätt beror förmodligen på den oklara lagstiftningen gällande riktvärden på grumlighet och på bristfälliga anvisningar för hur referensprovtagning av grumlighet bör utformas. För att komma åt problematiken med opålitliga riktvärden borde riktvärden därför anpassas till enskilda vattendrag. I detta examensarbete gjordes ett försök att ta fram en metod för att kunna sätta vattendragsanpassade riktvärden. En dynamisk modell utvecklades för att ta fram grumlighet utifrån jordbruksareal, andel lera i avrinningsområdet samt vattenflöde. Modellen gav bäst, men trots allt inte tillfredställande, resultat för vattendrag med avrinningsområden mindre än 100 km2. För vattendrag som hade ett större avrinningsområde blev modellresultaten sämre, förmodligen på grund av en komplex samverkan mellan olika drivvariabler, där vissa inte ens togs hänsyn till i modellen. För att komma vidare med vattendragsanpassade riktvärden i Sverige föreslås fortsättningsvis en omfattande nationell satsning framförallt för större värdefulla vattendrag. Denna satsning bör innefatta anpassning av mer avancerade modeller för grumlighet till svenska förhållanden. Sammanfattningsvis visar studien tydligt att det finns ett stort behov av att förbättra metoderna för att kontrollera grumlighet samt att ta fram riktvärden anpassade utifrån naturliga grumlighetsnivåer i de olika vattendragen.

  • 20.
    Antans, Andis
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Multi-Criteria Decision Analysis in Wind power Project Development: Case study in Latvia2017Independent thesis Advanced level (degree of Master (One Year)), 10 poäng / 15 hpOppgave
    Abstract [en]

    Wind Power Project Development is a complicated, capital and resource-inclusive process, where a wide variety of factors have to be considered and several stakeholders have a significant say in the process. Decision making in such an environment is complex and has to be approached comprehensively. In order to sustain a structured and clear decision-making process, the sustainable energy industry has recognized Multi-Criteria Decision Analysis (MCDA) method as a suitable set of tools to aid in the decision-making process. One of the MCDA tools – PROMETHEE II, has been examined in this master thesis, to evaluate its eligibility as a decision making aid in wind power project development.

    To structurally and realistically evaluate the tool, it has been applied to a case study in Ventspils region, in Latvia. The author of this thesis has a preliminary agreement with the owners of the sites to develop the project, therefore, this thesis has a strong potential for a practical implementation in future. Four scenarios have been developed for an evaluation, contributing to four variations of the different amount of turbines erected, with two different hub heights, on two differently sized sites. The scenarios are assessed based on the interests of six key stakeholders. Their opinion on twelve criteria is examined.

    Input data for each criterion has been generated via WindPro and MS Excel software or by authors assessment based on the researched literature. PROMETHEE II is used to extrapolate a comprehensive and clear representation of the results.

    The evaluation of the MCDA method proved that MCDA tools, and PROMETHEE II, in particular, can provide excellent support in decision making in wind power development. A wide variety of input data, as well as the various and often contradicting interests by different stakeholders, can be taken into account, while, at the same time, a clear result that can assist in decision making, is generated. 

    Wind Power Project Development is a complicated, capital and resource-inclusiveprocess, where a wide variety of factors have to be considered and severalstakeholders have a significant say in the process. Decision making in such anenvironment is complex and has to be approached comprehensively. In order to sustaina structured and clear decision making process, sustainable energy industry hasrecognized Multi-Criteria Decision Analysis (MCDA) method as a suitable set of tools toaid in the decision making process. One of the MCDA tools – PROMETHEE II, hasbeen examined in this master thesis, to evaluate its eligibility as a decision making aidin wind power project development.To structurally and realistically evaluate the tool, it has been applied on a case study inVentspils region, in Latvia. The author of this thesis has a preliminary agreement withthe owners of the sites to develop the project, therefore, this thesis has a strongpotential for a practical implementation in future. Four scenarios have been developedfor an evaluation, contributing to four variations of different amount of turbines erected, with two different hub heights, on two differently sized sites. The scenarios are assessed based on the interests of six key stakeholders. Their opinion on twelve criteria examined. Input data for each criterion has been generated via WindPro and MS Excel software orby authors assessment based on the researched literature. PROMETHEE II is used to extrapolate a comprehensive and clear representation of the results.The evaluation of the MCDA method proved that MCDA tools, and PROMETHEE II in particular, can provide excellent support in decision making in wind power development. Wide variety of input data, as well as the various and often contradicting interests by different stakeholders can be taken into account, while, at the same time, a clear result that can assist in decision making, is generated.

  • 21.
    Aronsson, Johanna
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för naturgeografi.
    Användning av tredimensionell geologisk modellering i hydrogeologiska utredningar: En fallstudie inför anläggandet av ett akviferlager i Brunkebergsåsen i Stockholm2015Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [sv]

    Akviferlager är en form av geoenergi där solenergi lagrad i grundvattnet används för att värma och kyla byggnader. Inför anläggandet av ett akviferlager är det viktigt med grundläggande geologiska och hydrogeologiska utredningar för att säkerställa funktion och kapacitet hos akviferlagret, samt minimera eventuell miljöpåverkan. I denna studie utvecklas en tredimensionell geologisk modell för att öka kunskapen om rullstensåsens geologiska uppbyggnad samt bedöma hur geologin kan komma att påverka det planerade akviferlagret. För att undersöka vilken påverkan manuella justeringar och tolkningar av geologin har, togs två geologiska modeller fram för jämförelse. Utifrån de geologiska modellerna uppskattades effektiv hydraulisk konduktivitet för åsen, d.v.s. sammanlagd konduktivitet för hela akviferens mäktighet, samt transporttid mellan akviferlagrets brunnspoler. Studien visar att akviferen består av sammanhängande jordlager med hög hydraulisk konduktivitet. Beroende på tolkningar och justeringar i modelleringsprocessen visar de två olika modellerna på skillnader vad gäller jordlagrens utbredning och mäktighet. Detta medför skillnader i effektiv hydraulisk konduktivitet mellan modellerna, vilket resulterar i relativt stora skillnader vad gäller transporttider mellan brunnspolerna. Tredimensionella geologiska modeller bedöms bidra till förbättrade hydrogeologiska utredningar då det är ett enkelt och effektivt sätt att bygga upp ett områdes geologi för översikt, tolkning och vidare studier i form av exempelvis grundvattenmodellering.

  • 22.
    Arvestål, Emma
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Changes in Arsenic Levels in the Precambrian Oceans in Relation to the Upcome of Free Oxygen2013Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    Life on Earth could have existed already 3.8 Ga ago, and yet, more complex, multicellular life did not evolve until over three billion years later, about 700 Ma ago. Many have searched for the reason behind this apparent delay in evolution, and the dominating theories put the blame on the hostile Precambrian environment with low oxygen levels and sulphide-rich oceans. There are, however, doubts whether this would be the full explanation, and this thesis therefore focuses on a new hypothesis; the levels of the redox sensitive element arsenic increased in the oceans as a consequence of the change in weathering patterns that followed the upcome of free oxygen in the atmosphere at about 2.4 billion years ago. Given its toxicity, this could have had negative effects upon the life of the time. To test the hypothesis, 66 samples from drill cores coming from South Africa and Gabon with ages between 2.7 and 2.05 Ga were analysed for their elemental composition, and their arsenic content were compared with carbon isotope data from the same samples. These confirmed that a rise in arsenic concentration following the upcome of free oxygen in the atmosphere and the onset of oxidative weathering of continental sulphides. Arsenic, which is commonly found in sulphide minerals, was weathered together with the sulphide and delivered into the oceans, where it in the Palaeoproterozoic increased to over 600% compared to the older Archaean levels, at least locally. Iron had the strongest control over the arsenic levels in the anoxic (ferruginous and sulphidic) oceans, probably due to its ability to remove arsenic through adsorption. During oxygenated conditions, sulphur instead had the strongest influence upon arsenic, likely because of the lack of dissolved iron. The highest arsenic levels were found in samples recognised as coming from oxygenated conditions, although this might be due to the oxygenation state of arsenic affecting its solubility. Arsenic is toxic already at low doses, especially if the necessary arsenic detoxification systems had not yet evolved. However, the lack of correlation between arsenic and changes in δ13C indicated that the increase of arsenic did not affect the primary production between 2.7 and 2.05 Ga. Thus, whether arsenic could have affected the evolution of life during the Mesoproterozoic remains to be shown.

  • 23.
    Arvestål, Emma
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Streng, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    A new species of Cyrtograptus (Graptoloidea) from the Llandovery of Västergötland (Sweden)2011Inngår i: The 2nd Wiman Meeting: Carl Wiman's Legacy: 100 years of Swedish Palaeontology, Uppsala, 2011, 2-2 s.Konferansepaper (Fagfellevurdert)
    Abstract [en]

    A new species of the genus Cyrtograptus from the late Llandovery of southern Sweden (Västergötland) is presented. The new species has been found near the top of Kinnekulle (Högkullen) in the Retiolites Shales, which are part of the lapworthi zone (late Telychian). Although it resembles the coeval C. lapworthi in appearance, a detailed comparison of the type material of C. lapworthi revealed distinct differences: the new species is more openly coiled in the proximal part, has a larger Two Thecae Repeat Distance (2TRD), and, most significantly, bears a second order cladium. Second order cladia are unknown from C. lapworthi. The new species is also compared with other species of Cyrtograptus that are characterized by second order cladia, such as the cotemporaneous C. laqueus and the slightly younger C. insectus (insectus zone; latest Telychian). However, C. laqueus differs from the new species in having a lower number of thecae separating the cladia, and also by the appearance of its proximal part, which forms a loop by crossing its own main stipe. C. insectus differs by having wider spaced cladia and a stronger coiled proximal part. Furthermore, the need of a redefinition of C. lapworthi is highlighted, due to the large morphological variations within this species.

  • 24.
    Arvestål, Emma
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Streng, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Cyrtograptids from the Telychian (upper Llandovery) of Kinnekulle Mountain, southern Sweden2012Konferansepaper (Annet vitenskapelig)
  • 25.
    Arvestål, Emma
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Streng, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Cyrtograptids from the Telychian (upper Llandovery) of Kinnekulle Mountain, southern Sweden2013Inngår i: GFF, ISSN 1103-5897, Vol. 135, nr 1, 45-56 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The late Llandovery graptolite fauna of the Retiolites Shales on Kinnekulle Mountain in the province of Västergötland has long been known but never illustrated or studied in detail. New collections of graptolites from an interval at the very top of the exposed succession confirm previous reports of cyrtograptids, which make the shales on Kinnekulle the youngest preserved Palaeozoic rocks in the area. The co-occurrence of Oktavites spiralis and Cyrtograptus lapworthi constrains the strata to the lower lapworthi Biozone of the upper Telychian. The associated graptolite fauna comprises numerous monograptids and Retiolites angustidens as well as Cyrtograptus kinnekullensis n. sp., characterised by its open coiling and the presence of a second-order cladium on the second thecal cladium. This early occurrence of a cyrtograptid species with a second-order cladium on Baltica matches evolutionary patterns observed in Laurentia, suggesting that the ability to grow cladia of both first and higher order evolved approximately, synchronously and at the very beginning of cyrtograptid evolution.

  • 26. Askebjer, P
    et al.
    Johansson, Sverker
    Högskolan för lärande och kommunikation, Högskolan i Jönköping, HLK, Ämnesforskning.
    On the Age vs Depth and Optical Clarity of Deep Ice at the South Pole1995Inngår i: Journal of Glaciology, nr 41, p 445- s.Artikkel i tidsskrift (Fagfellevurdert)
  • 27. Askebjer, P
    et al.
    Johansson, Sverker
    Högskolan för lärande och kommunikation, Högskolan i Jönköping, HLK, Ämnesforskning.
    Optical properties of the South Pole ice at depths between 0.8 and 1 km1995Inngår i: Science, nr 267, 1147-1150 s.Artikkel i tidsskrift (Annet vitenskapelig)
  • 28.
    Backman, Fredrick
    Umeå universitet, Humanistiska fakulteten, Institutionen för idé- och samhällsstudier.
    Från föhn till feu!: Esrange och den norrländska rymdverksamhetens tillkomsthistoria från sekelskiftet 1900 till 19662010Independent thesis Advanced level (degree of Master (One Year)), 20 poäng / 30 hpOppgave
    Abstract [en]

    This essay is about the origin, planning and establishment of the European Space Research Organisation's (ESRO) sounding rocket base Esrange outside Kiruna in Northern Sweden. Three main questions are examined. First I show there were not just scientific and technical but also political, economical as well as military reasons to build a European rocket base. Second, I scrutinize the reasons to choose Northern Sweden as the location for the rocket base. As it turns out, the main reasons were the favourable location of Northern Sweden within the aurora oval zone, the proximity of the Kiruna Geophysical Observatory, and the possibility to use a large, although not quite uninhabited, area where the launched rockets could crash. Finally, I examine the difficulty of talking about boundaries of various kinds, such as temporal, spatial and functional. The essay also provides a discussion on possible ways to continue research on this topic.

  • 29.
    Backman, Jan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi. Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi.
    Jakobsson, Martin
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi. Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för geologi och geokemi.
    Frank, Martin
    Sangiorgi, F
    Brinkhuis, Henk
    Sluijs, Appy
    Stickly, Catherine
    Gattacecca, Jerome
    Age/depth relationships for the ACEX sedimentary section recovered from the Lomonosov Ridge2007Konferansepaper (Annet (populærvitenskap, debatt, mm))
  • 30.
    Bagherbandi, Mohammad
    et al.
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad, Samhällsbyggnad, GIS. KTH Royal Institute of Technology, Stockholm, Sweden.
    Bai, Yongliang
    School of Geosciences, China University of Petroleum (East China), Qingdao, China.
    Sjöberg, Lars
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Tenzer, Robert
    NTIS - New Technologies for the Information Society, Faculty of Applied Sciences, University of West Bohemia, Plzeň, Czechia.
    Abrehdary, Majid
    KTH Royal Institute of Technology, Stockholm, Sweden.
    Miranda, Silvia
    Departamento de Geofísica y Astronomía, FCEFN Universidad Nacional de San Juan, San Juan, Argentina.
    Sanchez, Juan M. Alcacer
    Departamento de Geofísica y Astronomía, FCEFN Universidad Nacional de San Juan, San Juan, Argentina.
    Effect of the lithospheric thermal state on the Moho interface: a case study in South America2017Inngår i: Journal of South American Earth Sciences, ISSN 0895-9811, E-ISSN 1873-0647, Vol. 76, 198-207 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Gravimetric methods applied for Moho recovery in areas with sparse and irregular distribution of seismic data often assume only a constant crustal density. Results of latest studies, however, indicate that corrections for crustal density heterogeneities could improve the gravimetric result, especially in regions with a complex geologic/tectonic structure. Moreover, the isostatic mass balance reflects also the density structure within the lithosphere. The gravimetric methods should therefore incorporate an additional correction for the lithospheric mantle as well as deeper mantle density heterogeneities. Following this principle, we solve the Vening Meinesz-Moritz (VMM) inverse problem of isostasy constrained by seismic data to determine the Moho depth of the South American tectonic plate including surrounding oceans, while taking into consideration the crustal and mantle density heterogeneities. Our numerical result confirms that contribution of sediments significantly modifies the estimation of the Moho geometry especially along the continental margins with large sediment deposits. To account for the mantle density heterogeneities we develop and apply a method in order to correct the Moho geometry for the contribution of the lithospheric thermal state (i.e., the lithospheric thermal-pressure correction). In addition, the misfit between the isostatic and seismic Moho models, attributed mainly to deep mantle density heterogeneities and other geophysical phenomena, is corrected for by applying the non-isostatic correction. The results reveal that the application of the lithospheric thermal-pressure correction improves the RMS fit of the VMM gravimetric Moho solution to the CRUST1.0 (improves ∼ 1.9 km) and GEMMA (∼1.1 km) models and the point-wise seismic data (∼0.7 km) in South America.

  • 31.
    Bagherbandi, Mohammad
    et al.
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad.
    Sjöberg, Lars E.
    Royal Institute of Technology (KTH), Stockholm, Sweden.
    Improving gravimetric–isostatic models of crustal depth by correcting for non-isostatic effects and using CRUST2.02013Inngår i: Earth-Science Reviews, ISSN 0012-8252, E-ISSN 1872-6828, Vol. 117, 29-39 s.Artikkel, forskningsoversikt (Fagfellevurdert)
    Abstract [en]

    The principle of isostasy is important in different fields of geosciences. Using an isostatic hypothesis for estimating the crustal thickness suffers from the more or less incomplete isostatic model and that the observed gravity anomaly is not only generated by the topographic/isostatic signal but also by non-isostatic effects (NIEs). In most applications of isostatic models the NIEs are disregarded. In this paper, we study how some isostatic models related with Vening Meinez's isostatic hypothesis can be improved by considering the NIE. The isostatic gravity anomaly needs a correction for the NIEs, which varies from as much as 494 mGal to − 308 mGal. The result shows that by adding this correction the global crustal thickness estimate improves about 50% with respect to the global model CRUST2.0, i.e. the root mean square differences of the crustal thickness of the best Vening Meinesz type and CRUST2.0 models are 6.9 and 3.2 km before and after improvement, respectively. As a result, a new global model of crustal thickness using Vening Meinesz and CRUST2.0 models is generated. A comparison with an independent African crustal depth model shows an improvement of the new model by 6.8 km vs. CRUST2.0 (i.e. rms differences of 3.0 and 9.8 km, respectively). A comparison between oceanic lithosphere age and the NIEs is discussed in this study, too. One application of this study can be to improve crustal depth in areas where CRUST2.0 data are sparse and bad and to densify the resolution vs. the CRUST2.0 model. Other applications can be used to infer the viscosity of the mantle from the NIEs signal to study various locations around the Earth for understanding complete, over- and under-compensations of the topography.

  • 32.
    Bagherbandi, Mohammad
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Sjöberg, Lars E.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik. University of Gävle, Sweden .
    Improving gravimetric-isostatic models of crustal depth by correcting for non-isostatic effects and using CRUST2.02013Inngår i: Earth-Science Reviews, ISSN 0012-8252, E-ISSN 1872-6828, Vol. 117, 29-39 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The principle of isostasy is important in different fields of geosciences. Using an isostatic hypothesis for estimating the crustal thickness suffers from the more or less incomplete isostatic model and that the observed gravity anomaly is not only generated by the topographic/isostatic signal but also by non-isostatic effects (NIEs). In most applications of isostatic models the NIEs are disregarded. In this paper, we study how some isostatic models related with Vening Meinez's isostatic hypothesis can be improved by considering the NIE. The isostatic gravity anomaly needs a correction for the NIEs, which varies from as much as 494 mGal to -308 mGal. The result shows that by adding this correction the global crustal thickness estimate improves about 50% with respect to the global model CRUST2.0, i.e. the root mean square differences of the crustal thickness of the best Vening Meinesz type and CRUST2.0 models are 6.9 and 3.2 km before and after improvement, respectively. As a result, a new global model of crustal thickness using Vening Meinesz and CRUST2.0 models is generated. A comparison with an independent African crustal depth model shows an improvement of the new model by 6.8 km vs. CRUST2.0 (i.e. rms differences of 3.0 and 9.8 km, respectively). A comparison between oceanic lithosphere age and the NIEs is discussed in this study, too. One application of this study can be to improve crustal depth in areas where CRUST2.0 data are sparse and bad and to densify the resolution vs. the CRUST2.0 model. Other applications can be used to infer the viscosity of the mantle from the NIEs signal to study various locations around the Earth for understanding complete, over- and under-compensations of the topography.

  • 33.
    Bagherbandi, Mohammad
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geodesi och geoinformatik.
    Tenzer, R.
    Geoid-to-quasigeoid separation computed using the GRACE/GOCE global geopotential model GOCO02S -A case study of Himalayas and Tibet2013Inngår i: Terrestrial, Atmospheric and Oceanic Science, ISSN 1017-0839, Vol. 24, nr 1, 59-68 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The geoid-to-quasigeoid correction has been traditionally computed approximately as a function of the planar Bouguer gravity anomaly and the topographic height. Recent numerical studies based on newly developed theoretical models, however, indicate that the computation of this correction using the approximate formula yields large errors especially in mountainous regions with computation points at high elevations. In this study we investigate these approximation errors at the study area which comprises Himalayas and Tibet where this correction reaches global maxima. Since the GPS-leveling and terrestrial gravity datasets in this part of the world are not (freely) available, global gravitational models (GGMs) are used to compute this correction utilizing the expressions for a spherical harmonic analysis of the gravity field. The computation of this correction can be done using the GGM coefficients taken from the Earth Gravitational Model 2008 (EGM08) complete to degree 2160 of spherical harmonics. The recent studies based on a regional accuracy assessment of GGMs have shown that the combined GRACE/GOCE solutions provide a substantial improvement of the Earth's gravity field at medium wavelengths of spherical harmonics compared to EGM08. We address this aspect in numerical analysis by comparing the gravity field quantities computed using the satellite-only combined GRACE/GOCE model GOCO02S against the EGM08 results. The numerical results reveal that errors in the geoid-to-quasigeoid correction computed using the approximate formula can reach as much as ~1.5 m. We also demonstrate that the expected improvement of the GOCO02S gravity field quantities at medium wavelengths (within the frequency band approximately between 100 and 250) compared to EGM08 is as much as ±60 mGal and ±0.2 m in terms of gravity anomalies and geoid/quasigeoid heights respectively.

  • 34.
    Bagherbandi, Mohammad
    et al.
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad. KTH, Geodesy & Geoinformatics, Stockholm, Sweden.
    Tenzer, Robert
    School of Geodesy and Geomatics, Wuhan University, Wuhan, China.
    Geoid-to-Quasigeoid Separation Computed Using the GRACE/GOCE Global Geopotential Model GOCO02S: A Case Study of Himalayas and Tibet2013Inngår i: Terrestrial, Atmospheric and Oceanic Science, ISSN 1017-0839, Vol. 24, nr 1, 59-68 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The geoid-to-quasigeoid correction has been traditionally computed approximately as a function of the planar Bouguer gravity anomaly and the topographic height. Recent numerical studies based on newly developed theoretical models, however, indicate that the computation of this correction using the approximate formula yields large errors especially in mountainous regions with computation points at high elevations. In this study we investigate these approximation errors at the study area which comprises Himalayas and Tibet where this correction reaches global maxima. Since the GPS-leveling and terrestrial gravity datasets in this part of the world are not (freely) available, global gravitational models (GGMs) are used to compute this correction utilizing the expressions for a spherical harmonic analysis of the gravity field. The computation of this correction can be done using the GGM coefficients taken from the Earth Gravitational Model 2008 (EGM08) complete to degree 2160 of spherical harmonics. The recent studies based on a regional accuracy assessment of GGMs have shown that the combined GRACE/GOCE solutions provide a substantial improvement of the Earth’s gravity field at medium wavelengths of spherical harmonics compared to EGM08. We address this aspect in numerical analysis by comparing the gravity field quantities computed using the satellite-only combined GRACE/GOCE model GOCO02S against the EGM08 results. The numerical results reveal that errors in the geoid-to-quasigeoid correction computed using the approximate formula can reach as much as ~1.5 m. We also demonstrate that the expected improvement of the GOCO02S gravity field quantities at medium wavelengths (within the frequency band approximately between 100 and 250) compared to EGM08 is as much as ±60 mGal and ±0.2 m in terms of gravity anomalies and geoid/quasigeoid heights respectively.

  • 35.
    Bagherbandi, Mohammad
    et al.
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad.
    Tenzer, Robert
    Wuhan University, China.
    Sjöberg, Lars
    Royal Institute of Technology (KTH), Stockholm, Sweden.
    Novak, Pavel
    University of West Bohemia, Plzen, Czech Republic.
    Improved global crustal thickness modeling based on the VMM isostatic model and non-isostatic gravity correction2013Inngår i: Journal of Geodynamics, ISSN 0264-3707, Vol. 66, 25-37 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In classical isostatic models for a gravimetric recovery of the Moho parameters (i.e., Moho depths and density contrast) the isostatic gravity anomalies are usually defined based on the assumption that the topographic mass surplus and the ocean mass deficiency are compensated within the Earth’s crust. As acquired in this study, this assumption yields large disagreements between isostatic and seismic Moho models. To assess the effects not accounted for in classical isostatic models, we conduct a number of numerical experiments using available global gravity and crustal structure models. First, we compute the gravitational contributions of mass density contrasts due to ice and sediments, and subsequently evaluate respective changes in the Moho geometry. Residual differences between the gravimetric and seismic Moho models are then used to predict a remaining non-isostatic gravity signal, which is mainly attributed to unmodeled density structures and other geophysical phenomena. We utilize three recently developed computational schemes in our numerical studies. The apparatus of spherical harmonic analysis and synthesis is applied in forward modeling of the isostatic gravity disturbances. The Moho depths are estimated globally on a 1 arc-deg equiangular grid by solving the Vening-Meinesz Moritz inverse problem of isostasy. The same estimation model is applied to evaluate the differences between the isostatic and seismic models. We demonstrate that the application of the ice and sediment density contrasts stripping gravity corrections is essential for a more accurate determination of the Moho geometry. We also show that the application of the additional non-isostatic correction further improves the agreement between the Moho models derived based on gravity and seismic data. Our conclusions are based on comparing the gravimetric results with the CRUST2.0 global crustal model compiled using results of seismic surveys.

  • 36.
    Bagherbandi, Mohammad
    et al.
    Högskolan i Gävle, Akademin för teknik och miljö, Avdelningen för Industriell utveckling, IT och Samhällsbyggnad. KTH.
    Tenzer, Robert
    Royal Institute of Technology (KTH), Stockholm, Sweden .
    Sjöberg, L.E.
    Wuhan University, Wuhan, China .
    Moho depth uncertainties in the Vening-Meinesz Moritz inverse problem of isostasy2014Inngår i: Studia Geophysica et Geodaetica, ISSN 0039-3169, E-ISSN 1573-1626, Vol. 58, nr 2, 227-248 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    We formulate an error propagation model based on solving the Vening Meinesz-Moritz (VMM) inverse problem of isostasy. The system ofobservation equations in the VMM model defines the relation between theisostatic gravity data and the Moho depth  by means of a second-order Fredholm integralequation of the first kind. The corresponding error model (derived in aspectral domain) functionally relates the Moho depth errors with the commissionerrors of used gravity and topographic/bathymetric models. The error model alsoincorporates the non-isostatic bias which describesthe disagreement, mainly of systematic nature, between the isostatic andseismic models. The error analysis is conducted at the study area of theTibetan Plateau and Himalayas with the world largest crustal thickness. TheMoho depth uncertainties due to errors of the currently available globalgravity and topographic models are estimated to be typically up to 1-2 km,provided that the GOCE gravity gradient observables improved themedium-wavelength gravity spectra. The errors due to disregarding sedimentarybasins can locally exceed ~2 km. The largest errors (which cause a systematic bias betweenisostatic and seismic models) are attributed to unmodeled mantleheterogeneities (including thecore-mantle boundary) and other geophysical processes. These errors aremostly less than 2 km under significant orogens (Himalayas, Ural), but canreach up to ~10 km under the oceanic crust.

  • 37.
    Bajdek, Piotr
    et al.
    Aleja Najswieztszej Maryi Panny 20-20A, PL-42200 Czestochowa, Poland..
    Qvarnström, Martin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Owocki, Krzysztof
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Sulej, Tomasz
    Polish Acad Sci, Inst Paleobiol, Twarda 51-55, PL-00818 Warsaw, Poland..
    Sennikov, Andrey G.
    Russian Acad Sci, Borissiak Paleontol Inst, Profsoyuznaya 123, Moscow 117997, Russia.;Kazan Fed Univ, Kremlyovskaya 18, Kazan 420008, Russia..
    Golubev, Valeriy K.
    Russian Acad Sci, Borissiak Paleontol Inst, Profsoyuznaya 123, Moscow 117997, Russia.;Kazan Fed Univ, Kremlyovskaya 18, Kazan 420008, Russia..
    Niedzwiedzki, Grzegorz
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Biologiska sektionen, Institutionen för organismbiologi, Evolution och utvecklingsbiologi.
    Microbiota and food residues including possible evidence of pre-mammalian hair in Upper Permian coprolites from Russia2016Inngår i: Lethaia: an international journal of palaeontology and stratigraphy, ISSN 0024-1164, E-ISSN 1502-3931, Vol. 49, nr 4, 455-477 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Coprolites (fossil faeces) provide direct evidence on the diet of its producer and unique insights on ancient food webs and ecosystems. We describe the contents of seven coprolites, collected from the Late Permian Vyazniki site of the European part of Russia. Two coprolite morphotypes (A, B) contain remains of putative bacteria, cyanobacteria, fungi, protists, invertebrate eggs, arthropod elements, undigested bone and tooth fragments, fish scales and elongated hair-like structures with hollow interiors. Content, size and shape of the coprolites together with the associated body fossil record suggest that the most probable scat-producers were carnivorous tetrapods; the bone-rich morphotype A reveals short food retention time and a fast metabolism and is therefore assigned to therapsid carnivores whereas morphotype B with rarer and degraded bones are assigned to archosauromorphs or other non-therapsid carnivores. The general coprolite matrix contains abundant micron-sized spheres and thin-walled vesicles which are interpreted as oxide and phosphatic pseudomorphs after microbial cells. From analyses of the undigested bones, we infer that they represent remains of actinopterygian fish, a therapsid and unrecognizable parts of amphibians and/or reptiles. Additionally, hair-like structures found in one coprolite specimen occur as diagenetically altered (oxide-replaced) structures and moulds (or partly as pseudomorphs) in a microcrystalline carbonate-fluoride-bearing calcium phosphate. This suggests that the latest Permian therapsids probably were equipped with hair-like integument or hairsuit. If true, this is by far the oldest evidence of this mammalian character in the stem group of mammals.

  • 38.
    Balazadegan Sarvrood, Yashar
    et al.
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik och Geodesi.
    Amin, Md Nurul
    KTH, Skolan för arkitektur och samhällsbyggnad (ABE), Samhällsplanering och miljö, Geoinformatik och Geodesi.
    Server Based Real Time GPS-IMU Integration Aided by Fuzzy Logic Based Map Matching Algorithm for Car Navigation2011Independent thesis Advanced level (degree of Master (Two Years)), 30 poäng / 45 hpOppgave
    Abstract [en]

    The stand-alone Global Positioning System (GPS) or an Integrated GPS and Dead Reckoning Systems (such as Inertial Navigation System or Odometer and magnetometer) have been widely used for vehicle navigation. An essential process in such an application is to map match the position obtained from GPS (or/and other sensors) on a digital road network map.

    GPS positioning is relatively accurate in open sky conditions, but its position is not accurate in dense urban canyon conditions where GPS is affected by signal blockage and multipath. High sensitivity GPS (HS GPS) receivers, can increase the availability, but are affected by multipath and cross correlation due to weak signal tracking. Inertial navigation system can be used to bridge GPS gaps, However, position and velocity results in such conditions are typically biased, therefore, fuzzy logic  based map matching, is mostly used because it can take noisy, imprecise input, to yield crisp (i.e. numerically accurate) output. Fuzzy logic can be applied effectively to map match the output from a High sensitivity GPS receiver or integrated GPS and INS in urban canyons because of its inherent tolerance to imprecise inputs.

    In this thesis stand-alone GPS positioning and integrated GPS and Inertial Measurement Unit (IMU) positioning aided by fuzzy logic based map matching for Stockholm urban and suburban areas are performed.  A comparison is carried out between, Map matching for stand-alone GPS and integrated GPS and IMU. Stand-alone GPS aided map matching algorithms identifies 96.4% of correct links for rural area, 92.6% for urban area (car test) and 93.4% for bus test in urban area. Integrated GPS and IMU aided map matching algorithms identifies 97.3% of correct links for rural area, 94.4% for urban area (car test) and 94.4% for bus test in urban area. Integrated GPS and Inertial Measurement Unit produces better vehicle azimuth than stand-alone GPS, especially at low speed. Furthermore, there are five more fuzzy rules based on gyro rate in integrated GPS and IMU map matching algorithm. Therefore, it shows better map matching results. GPS blackout happens rarely in Stockholm, because there are not many tall buildings in this city. Therefore, the integrated GPS and IMU aided by map matching shows only small improvement over stand-alone GPS aided by map matching.

  • 39.
    Balthasar, Uwe
    et al.
    University of Glasgow.
    Brazeau, Martin
    Brock, Glenn
    Macquarie University, Australia.
    Harper, David
    Durham University.
    Holmer, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    McGowan, Alistair
    Skovsted, Christian B.
    Naturhistoriska Riksmuseet.
    Streng, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Zhang, Zhifei
    Northwest University, Xi'an.
    Early evolution of biomineralization in brachiopods2012Konferansepaper (Annet vitenskapelig)
  • 40.
    Balthasar, Uwe
    et al.
    University of Glasgow.
    Brazeau, Martin
    Brock, Glenn
    Macquarie University, Australia.
    McGowan, Alistair
    Harper, David
    Holmer, Lars
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Skovsted, Christian B.
    Naturhistoriska Riksmuseet.
    Streng, Michael
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Paleobiologi.
    Zhang, Zhifei
    Brachiopod phylogeny revisited: Using stem groups to flesh out molecular tree topology2011Konferansepaper (Annet vitenskapelig)
  • 41. Baranizadeh, Elham
    et al.
    Murphy, Benjamin N.
    Julin, Jan
    Falahat, Saeed
    SMHI, Samhälle och säkerhet.
    Reddington, Carly L.
    Arola, Antti
    Ahlm, Lars
    Mikkonen, Santtu
    Fountoukis, Christos
    Patoulias, David
    Minikin, Andreas
    Hamburger, Thomas
    Laaksonen, Ari
    Pandis, Spyros N.
    Vehkamaki, Hanna
    Lehtinen, Kari E. J.
    Riipinen, Ilona
    Implementation of state-of-the-art ternary new-particle formation scheme to the regional chemical transport model PMCAMx-UF in Europe2016Inngår i: Geoscientific Model Development, ISSN 1991-959X, E-ISSN 1991-9603, Vol. 9, nr 8, 2741-2754 s.Artikkel i tidsskrift (Fagfellevurdert)
  • 42.
    Bate, Stephen
    et al.
    Royal Holloway Univ London, Quaternary Res Ctr, Dept Geog, Egham TW20 0EX, Surrey, England..
    Stevens, Thomas
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Luft-, vatten och landskapslära. Royal Holloway Univ London, Quaternary Res Ctr, Dept Geog, Egham TW20 0EX, Surrey, England.; Univ Novi Sad, Fac Sci, Lab Paleoenvironmental Reconstruct, Trg D Obradov 2, Novi Sad 21000, Serbia..
    Buylaert, Jan-Pieter
    Univ Aarhus, Dept Earth Sci, Nord Lab Luminescence Dating, Riso DTU, DK-4000 Roskilde, Denmark.; Ctr Nucl Technol, Riso DTU, DK-4000 Roskilde, Denmark..
    Markovic, Slobodan
    Univ Novi Sad, Fac Sci, Lab Paleoenvironmental Reconstruct, Trg D Obradov 2, Novi Sad 21000, Serbia..
    Roos, Per
    Ctr Nucl Technol, Riso DTU, DK-4000 Roskilde, Denmark..
    Tasic, Nenad
    Univ Belgrade, Fac Philosophy, Dept Archaeol, Belgrade, Serbia..
    Pottery versus sediment: Optically stimulated luminescence dating of the Neolithic Vinca culture, Serbia2017Inngår i: Quaternary International, ISSN 1040-6182, E-ISSN 1873-4553, Vol. 429, 45-53 s.Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Optically stimulated luminescence (OSL) dating was applied to the Neolithic Vinca culture's type-site, Vinca Belo-Brdo, to establish best protocols for routine luminescence dating of similar Holocene sites, critical in understanding Neolithic to Chalcolithic cultural development. Equivalent dose (De) values were investigated for sediment samples using 63-90 mm grains on large and small aliquots, and single-grain laser luminescence (SGLL), and for pottery samples using large aliquots of 4-11 mm grains. The effects of changing water content and the different techniques available to establish radionuclide concentration were explored for their impacts on dose rate (Dr) estimates. Ages for two pottery samples of 6.74 +/- 0.37 ka and 7.04 +/- 0.47 ka are in line with the existing AMS radiocarbon chronology for the site and are regarded as the best dates available. Sediment samples at Vinca show poor signal strength, and the uncertainty over past water content, in addition to the possibility of mixing and/or partial bleaching of the quartz, means that we do not recommend the use of sediment-derived ages at complex archaeological sites such as Vinca. OSL dating of fired pottery however, presents a powerful tool for generating independent chronologies at archaeological sites as well as providing additional constraints for Bayesian age models.

  • 43.
    Bax, Gerhard
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Miljö- och landskapsdynamik. ELD.
    Remote sensing and 3D visualization of geological structures in mountain ranges:: examples from the Northern Scandinavian Caledonides and the south Tibetan Himalayas2004Inngår i: The 26th Nordic Geological Winter Meeting: Abstract volume, 2004, 105- s.Konferansepaper (Fagfellevurdert)
  • 44.
    Bax, Gerhard
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper, Miljö- och landskapsdynamik. ELD.
    Buchroithner, ManfredDepartment of Cartography.
    Proceedings of the 5th International Symposium of the use of Remote Sensing in Maountain Cartography: High-Mountain Remote Sensing Cartography 19982002Konferanseproceedings (Fagfellevurdert)
  • 45.
    Bazzi, Mohamad
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Extinction Dynamics in Selachimorpha: Tracking Dental Morphology Across the K–Pg Boundary2016Independent thesis Advanced level (degree of Master (Two Years)), 20 poäng / 30 hpOppgave
    Abstract [en]

    The study of the effects of the Cretaceous–Palaeogene mass extinction (K–Pg) on Selachimorpha (shark) evolution is limited to assessments of taxonomic richness. Prior work on the fossil record of neoselachians both on a global- and regional scale has shown that sharks achieved great taxonomic diversity in the Late Cretaceous but were subsequently punctuated by the K–Pg extinction. The ecological significance of this bioevent on global shark communities is particularly poorly understood with contrasting views on patterns of extinction selectivity. Similar to actinopterygian fishes, the extinction of sharks was focused on large-bodied pelagic piscivorous. However, patterns of trophic selectivity in sharks were recently contested and posited as random with respect to environment and ecology. Following the extinction at the K–Pg boundary, the ecological role of sharks in the earliest Palaeocene is said to have diminished and contrary to actinopterygian fishes did not experience an adaptive radiation.Current analyses are based on assessments of taxonomic diversity and absolute faunal abundance, and lack the necessary morphological framework with which to adequately test ecological dynamics in sharks across the K–Pg. To test both previous and newly formulated macroevolutionary hypotheses, shark tooth morphology was quantified via landmark- and semilandmark-based geometric morphometrics and used to reconstruct patterns of disparity and morphospace occupation across the K–Pg boundary. The newly assembled morphometric dataset comprises 1457 shark teeth spanning the Maastrichtian–Palaeocene compiled from published images.The results reveal (1) near-stasis in dental-shape disparity in Selachimorpha (globally) across the K–Pg boundary, and (2) a decrease in morphospace occupation associated with cutting-type dentitions. Considered jointly, observed disparity and morphospace patterns in Selachimorpha do not conform to the predictions of a non-random extinction model. However, dissecting patterns of disparity and morphospace occupation along phylogenetic lines reveal differential responses to the extinction, affirming phylogenetic selectivity with trophic implications.Testing for ecological release in sharks, using disparity dynamics in lamniforms and carcharhiniforms as a model, is shown to be complex. Pattern across the extinction event reveal an increase in tooth morphologies of carcharhiniforms in previously underexplored area of morphospace that were previously occupied by lamniforms, an area corresponding to macropredaceous forms (e.g. anacoracids and pseudocoracids). However, the observed increases in cutting-type dentitions in carcharhiniforms are largely driven by the proliferation of triakids, that are not ecologically equivalent to macropredatory lamniforms. I suggest that the combined effect of a selective decline in lamniform ecodiversity and the diversification of mid-trophic small-sized pelagic bony fish triggered the post-Cretaceous diversification of triakids. The K–Pg boundary was therefore crucial in setting the stage for the carcharhiniform-dominated selachimorph community that can be seen today.

    Fulltekst tilgjengelig fra 2018-01-01 20:00
  • 46.
    Bazzi, Mohamad
    et al.
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper.
    Einarsson, Elisabeth
    Lund University.
    Kear, Benjamin
    Uppsala universitet, Teknisk-naturvetenskapliga vetenskapsområdet, Geovetenskapliga sektionen, Institutionen för geovetenskaper. Uppsala universitet, Enheten för musik och museer, Evolutionsmuseet.
    Late Cretaceous (Campanian) actinopterygian fishes from the Kristianstad Basin of southern Sweden2016Inngår i: Mesozoic Biotas Of Scandinavia And Its Arctic Territories, Geological Society, 2016, 277-292 s.Kapittel i bok, del av antologi (Fagfellevurdert)
    Abstract [en]

    Although a diverse range of aquatic vertebrates are documented from the Upper Cretaceous (mid-Campanian) marine strata of the Kristianstad Basin in southern Sweden, only chondrichthyans and marine amniotes have been described in detail to date. In contrast, coeval actinopterygians are virtually unreported, yet their remains are extremely abundant at most sampled localities. A comprehensive assessment of these fossils has identified the first Late Cretaceous actinopterygian fauna from the Fennoscandian Shield, incorporating indeterminate lepisosteids, the durophagous pycnodontid Anomoeodus subclavatus, the predatory pachycormid Protosphyraena sp., a large ichthyodectid, pachyrhizodontids resembling Pachyrhizodus, the enchodontid Enchodus cf. gladiolus and indeterminate small teleosts. These taxa are diagnosed mainly from isolated teeth and scales, implying substantial taphonomic loss prior to burial. Moreover, the prolific recovery of actinopterygian skeletal remnants in recent excavations suggests that historical collecting biases, rather than ecological paucity, have contributed to their under-representation in the Swedish Cretaceous record. Palaeobiogeographically, the Kristianstad Basin actinopterygians show compositional resemblance to assemblages from the Northern European Platform and the Western Interior Seaway of North America, advocating distributional communication across the Boreal proto-Atlantic Ocean.

  • 47.
    Becher, Marina
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Cryogenic soil processes in a changing climate2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    A considerable part of the global pool of terrestrial carbon is stored in high latitude soils. In these soils, repeated cycles of freezing and thawing creates soil motion (cryoturbation) that in combination with other cryogenic disturbance processes may play a profound role in controlling the carbon balance of the arctic soil. Conditions for cryogenic soil processes are predicted to dramatically change in response to the ongoing climate warming, but little is known how these changes may affect the ability of arctic soils to accumulate carbon. In this thesis, I utilize a patterned ground system, referred to as non-sorted circles, as experimental units and quantify how cryogenic soil processes affect plant communities and carbon fluxes in arctic soils. I show that the cryoturbation has been an important mechanism for transporting carbon downwards in the studied soil over the last millennia. Interestingly, burial of organic material by cryoturbation appears to have mainly occurred during bioclimatic events occurring around A.D. 900-1250 and A.D. 1650-1950 as indicated by inferred 14C ages. Using a novel photogrammetric approach, I estimate that about 0.2-0.8 % of the carbon pool is annually subjected to a net downward transport induced by the physical motion of soil. Even though this flux seems small, it suggests that cryoturbation is an important transporter of carbon over centennial and millennial timescales and contributes to translocate organic matter to deeper soil layers where respiration proceeds at slow rates. Cryogenic processes not only affect the trajectories of the soil carbon, but also generate plant community changes in both species composition and abundance, as indicated by a conducted plant survey on non-sorted circles subjected to variable differential frost heave during the winter. Here, disturbance-tolerant plant species, such as Carex capillaris and Tofieldia pusilla, seem to be favoured by disturbance generated by the differential heave. Comparison with findings from a previous plant survey on the site conducted in the 1980s suggest that the warmer temperatures during the last decades have resulted in decreased differential heave in the studied non-sorted circles. I argue that this change in cryogenic activity has increased abundance of plants present in the 1980s. The fact that the activity and function of the non-sorted circles in Abisko are undergoing changes is further supported by their contemporary carbon dioxide (CO2) fluxes. Here, my measurements of CO2 fluxes suggest that all studied non-sorted circles act as net CO2 sources and thus that the carbon balance of the soils are in a transition state. My results highlight the complex but important relationship between cryogenic soil processes and the carbon balance of arctic soils.

  • 48.
    Becher, Marina
    Umeå universitet, Institutionen för ekologi, miljö och geovetenskap.
    Cryogenic soil processes in a changing climate2016Doktoravhandling, med artikler (Annet vitenskapelig)
    Abstract [en]

    A considerable part of the global pool of terrestrial carbon is stored in high latitude soils. In these soils, repeated cycles of freezing and thawing creates soil motion (cryoturbation) that in combination with other cryogenic disturbance processes may play a profound role in controlling the carbon balance of the arctic soil. Conditions for cryogenic soil processes are predicted to dramatically change in response to the ongoing climate warming, but little is known how these changes may affect the ability of arctic soils to accumulate carbon. In this thesis, I utilize a patterned ground system, referred to as non-sorted circles, as experimental units and quantify how cryogenic soil processes affect plant communities and carbon fluxes in arctic soils. I show that the cryoturbation has been an important mechanism for transporting carbon downwards in the studied soil over the last millennia. Interestingly, burial of organic material by cryoturbation appears to have mainly occurred during bioclimatic events occurring around A.D. 900-1250 and A.D. 1650-1950 as indicated by inferred 14C ages. Using a novel photogrammetric approach, I estimate that about 0.2-0.8 % of the carbon pool is annually subjected to a net downward transport induced by the physical motion of soil. Even though this flux seems small, it suggests that cryoturbation is an important transporter of carbon over centennial and millennial timescales and contributes to translocate organic matter to deeper soil layers where respiration proceeds at slow rates. Cryogenic processes not only affect the trajectories of the soil carbon, but also generate plant community changes in both species composition and abundance, as indicated by a conducted plant survey on non-sorted circles subjected to variable differential frost heave during the winter. Here, disturbance-tolerant plant species, such as Carex capillaris and Tofieldia pusilla, seem to be favoured by disturbance generated by the differential heave. Comparison with findings from a previous plant survey on the site conducted in the 1980s suggest that the warmer temperatures during the last decades have resulted in decreased differential heave in the studied non-sorted circles. I argue that this change in cryogenic activity has increased abundance of plants present in the 1980s. The fact that the activity and function of the non-sorted circles in Abisko are undergoing changes is further supported by their contemporary carbon dioxide (CO2) fluxes. Here, my measurements of CO2 fluxes suggest that all studied non-sorted circles act as net CO2 sources and thus that the carbon balance of the soils are in a transition state. My results highlight the complex but important relationship between cryogenic soil processes and the carbon balance of arctic soils.

  • 49.
    Becher, Marina
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Börlin, Niclas
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för datavetenskap.
    Klaminder, Jonatan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Measuring soil motion with terrestrial close range photogrammetry in periglacial environments2014Konferansepaper (Annet vitenskapelig)
    Abstract [en]

    Cryoturbation plays an important role in the carbon cycle as it redistributes carbon deeper down in the soil where the cold temperature prevents microbial decomposition. This contribution is also included in recent models describing the long-term build up of carbon stocks in artic soils. Soil motion rate in cryoturbated soils is sparsely studied. This is because the internal factors maintaining cryoturbation will be affected by any excavation, making it impossible to remove soil samples or install pegs without changing the structure of the soil. So far, mainly the motion of soil surface markers on patterned ground has been used to infer lateral soil motion rates. However, such methods constrain the investigated area to a predetermined distribution of surface markers that may result in a loss of information regarding soil motion in other parts of the patterned ground surface.

    We present a novel method based on terrestrial close range (<5m) photogrammetry to calculate lateral and vertical soil motion across entire small-scale periglacial features, such as non-sorted circles (frost boils). Images were acquired by a 5-camera calibrated rig from at least 8 directions around a non-sorted circle. During acquisition, the rig was carried by one person in a backpack-like portable camera support system. Natural feature points were detected by SIFT and matched between images using the known epipolar geometry of the calibrated rig. The 3D coordinates of points matched between at least 3 images were calculated to create a point cloud of the surface of interest. The procedure was repeated during two consecutive years to be able to measure any net displacement of soil and calculate rates of soil motion. The technique was also applied to a peat palsa where multiple exposures where acquired of selected areas.

    The method has the potential to quantify areas of disturbance and estimate lateral and vertical soil motion in non-sorted circles. Furthermore, it should be possible to quantify peat erosion and rates of desiccation crack formations in peat palsas. This tool could provide new information about cryoturbation rates that could improve existing soil carbon models and increase our understanding about how soil carbon stocks will respond to climate change.

  • 50.
    Becher, Marina
    et al.
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Olofsson, Johan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Berglund, Louise
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Klaminder, Jonatan
    Umeå universitet, Teknisk-naturvetenskapliga fakulteten, Institutionen för ekologi, miljö och geovetenskap.
    Decreased cryogenic disturbance: one of the potential mechanisms behind the shrubification of non-sorted circles in subarctic SwedenManuskript (preprint) (Annet vitenskapelig)
    Abstract [en]

    During the last few decades, the arctic has experienced large-scale vegetation changes often evident as widespread greening (increased NDVI) in satellite images. Understanding the mechanisms behind this greening is crucial for our ability to predict future vegetation changes. The objective of this study was to test the hypothesis that decreased cryogenic disturbances have contributed to the greening of patterned ground fields (non-sorted circles) in the study site (Abisko, Northern Sweden) during the last few decades. The hypothesis was tested by surveying the composition of plant communities across a gradient in cryogenic disturbance and by reinvestigating plant communities previously surveyed in the 1980s to scrutinise how these communities changed in response to reduced cryogenic disturbance. Whereas the historical changes in species occurrence associated with decreased cryogenic disturbances were fairly consistent with the changes along the contemporary gradient of cryogenic disturbances, the species abundance revealed important transient changes highly dependent on the initial plant community composition. Our results imply that the decreased environmental stress from differential heave during winter in recent decades is one of the mechanisms that has contributed to the greening of the patterned ground in the study area, although more than a few decades are likely required before this decreased stress contributes in a substantial way to the on-going shrubification. 

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