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Inlandsvatten, exempelvis sjöar och floder, har en betydande roll för den globala kolcykeln. Förutom att dessa vatten transporterar kol mellan kontinenterna och havet så förekommer en mängd processer som påverkar kolomsättningen i dessa system. Inlandsvatten kan fånga in (fixera) koldioxid från atmosfären via fotosyntes, men en stor del av kolet i inlandsvatten transporteras från land. Detta kol kan antingen emitteras till atmosfären som koldioxid eller metan, lagras på botten av sjöar och reservoarer eller transporteras (exporteras) till havet genom floder och grundvatten. Genom att sammanställa litteratur som i huvudsak publicerats mellan 2007 och 2017 konkluderas att 3,6 Pg C y-1 transporteras till inlandsvatten från världens kontinenter. Av detta emitteras 2,3 Pg C y-1 till atmosfären innan det når havet, 0,15 Pg C y-1 sedimenteras i sjöar och dammar medan 1,1 Pg C-1 exporteras till havet. För att förstå hur människan påverkar kolomsättningen globalt krävs en korrekt beskrivning av de naturliga flödena av kol mellan hav, land och atmosfär. Förbättringspotential och osäkerheter gällande den kvantitativa uppskattningen om inlandsvatten som en del i den terrestra kolcykeln finns bland annat kopplat till små vattenansamlingar, då dessa inte är fullständigt kartlagda. En bättre geografisk spridning för den data som ligger till grund för globala uppskattningar krävs också för att förbättra förståelsen för inlandsvattens roll i den terrestra kolcykeln. / Inland waters, for example lakes and rivers, play a considerable role in the global carbon cycle. In addition to transport carbon between the continents and the oceans, a number of processes occur during the transport along the hydrological chain. Inland water could directly take up carbon dioxide from the atmosphere though photosynthesis, but a vast amount of the carbon origins from land. The carbon could either be emitted to the atmosphere as carbon dioxide or methane, stored at the bottom of lakes or reservoirs and/or transported (exported) to the ocean through rivers or groundwater. In this study, publications from 2007 to 2017 were reviewed, and the conclusion is drawn that 3,6 Pg C y-1 are exported to inland waters from land. 2,3 Pg C y-1 are emitted to the atmosphere, 0,15 Pg C y-1 is buried in the sediments of lakes and reservoirs and 1,1 Pg C y-1 is exported to the ocean. To understand how human affects the global carbon budget, a correct description of the natural migration of carbon between the ocean, the continents and the atmosphere is needed. Potential of improvement and uncertainties related to the quantitative estimates of emission, sedimentation and export are to a large extent connected to the poor surveys of small lakes and ponds. A more representative global distribution of the data is also needed for a better understanding of the role of inland waters in the terrestrial carbon cycle.

For a better understanding of how to search for an extraterrestrial life, scientists study hidden biospheres on Earth. The subseafloor crust is recognized as a vast microbial habitat and it is hypothesized that extremophilic microorganisms, occurring there, can be the first living organisms on Earth. Those extremophiles does not require oxygen due their ability to derive bioavailable energy from fluid-rock interactions, resembling conditions on Mars. Hence, in this study, geological samples from such environments are analysed. Overall, this report examines a concept of biogenicity and evaluates a set of methods used for the determination of biologic origin. Fossilized microbial remains were discovered in unconsolidated sediments from the volcaniclastic apron of Gran Canaria and in aragonite veins in ultramafic rocks from the North Pond at the Mid-Atlantic Ridge. Mentioned sediments and rocks were collected during Ocean Drilling Program (ODP) Leg 157 and 209. The fossil record from Gran Canaria is consistent with Foraminifera. The microbial remains from North Pond are consistent with Frutexites microstromatolites. Both fossilized communities have characteristic compositions associated with carbonaceous matter (CM) and different configurations of trace elements such as Si, Al, Mg, Mn, Ni, Fe, and Co. This study confirms the biologic origin of the fossilized remains and shows that the applied methods are suitable for astrobiological application. / För en bättre förståelse på hur man söker efter utomjordiskt liv, studerar forskare dem dolda biosfärer på jorden. Djuphavsbotten är uppskattad att vara ett stort mikrobiellt habitat och det antas att extremofila mikroorganismer, som förekommer där, kan vara de första levande organismerna på jorden. Dessa extremofiler kräver inte syre på grund av deras förmåga att härleda biologiskt tillgänglig energi från vätske-bergartsinteraktioner, vilket liknar förhållandena på Mars. I denna studie analyseras därför geologiska prover från sådana miljöer. Övergripande, granskar denna rapport begreppet biogenecitet och utvärderar en uppsättning av metoder, som används för bestämning av biologiskt ursprung. Fossiliserade mikrobiella lämningar återfanns i okonsoliderat sediment från Gran Canarias vulkaniklastiska förkläde och i aragonitåror i ultramafiska bergarter från North Pond vid Mittatlantiska ryggen. Nämnda sediment och bergarter samlades in under Ocean Drilling Program (ODP) Leg 157 och 209. Det fossila arkivet från Gran Canaria överensstämmer med Foraminifera. Dem mikrobiella resterna från North Pond är förenliga med Frutexites mikrostromatoliter. Båda dem fossiliserade samhällena har karakteristiska kompositioner associerade med kolhaltiga ämnen (CM) och olika konfigurationer av spårämnen, såsom Si, Al, Mg, Mn, Ni, Fe och Co. Denna studie bekräftar biologiska ursprungen hos dem fossila lämningarna och visar att applicerade metoder är lämpliga för astrobiologisk tillämpning.

In this study, groundwater resource potential (GRP) for Västervik municipality has been investigated using the methodology developed in the article by Earon et al. (2015). The aim was to test the reliability of the methodology for groundwater mapping, as to further add to the knowledge base of groundwater access. The GRP-methodology is a linear additive multicriteria analysis where geohydrological indicators are scored, classified into groups, then multiplied by weights calculated using Principal Component Analysis (PCA). The classification and validation were performed against specific capacity [L/(h*m)], which is a well's capacity calculated at drilling, per meter well. GRP was calculated in different sets based on 13 geohydrological variables such as altitude and Topographic Wetness Index (TWI). The results included correlation tests for Kendall's tau (0.06-0.13), Spearmans rho (0.09-0.19) with a total accuracy of 52-55%. Positive but low values ​​for Cohen´s kappa indicated that all calculations performed better than a random generator, but not by margin. Calculations of VIP (Variables importance on PLS projection), based on Partial Least Squares (PLS), identified Altitude, Earth type, Drainage density and TWI as the most influential indicators for the analysis.The conclusions of this study were, among other things, that the GRP methodology had low predictivity due to the weak relationships between the indicators and the specific capacity. The weaknesses could also be due to the fact that specific capacity has weaknesses as a validation variable for groundwater resource potential linked to uncertainties of the capacity measured at wellbore. The study shows that further development of the weighting scheme by integrating PLS would be beneficial, as PLS calculates the variance of the indicators based on the specific capacity, instead of assuming it as a PCA. / I denna studie har grundvattenresurspotential (GRP) för Västerviks kommun undersökts med hjälp av metodik från artikeln av Earon et al.(2015). Metodiken användes för att ta fram översiktligt underlag till grundvattenresursplanering på ett billigt och effektivt sätt och är därför av intresse för beslutsfattare och konsulter. Exempel för dessa användningsområden är bland annat vid grundvattenresursplanering och vid brunnsborrning. Syftet var att testa metodikens pålitlighet för grundvattenkartläggning. Endast öppen data användes i undersökningen vilket krävde små insatser jämfört med traditionell kartering. Stora möjligheter finns därmed vid användande av metodiken för grundvattenresursplanering och brunnsborrning.  Metodiken är baserad på en linjärt additiv multikriterieanalys där indikatorer såsom altitud, topografiskt fuktighetsindex (TWI) och bergarter poängsätts, klassificeras i grupper, för att sedan multipliceras med vikter beräknade med hjälp av principalkomponent analys (PCA). Klassificeringen och valideringen utfördes gentemot specifik kapacitet [L/(h*m)], vilket är en brunns kapacitet beräknad vid borrning, per meter brunnsdjup, hämtad från SGUs brunnsarkiv. Brunnarna delades slumpartat upp i 70 % kalibreringsbrunnar och 30 % valideringsbrunnar. GRP beräknades i olika varianter utifrån 13 variabler (altitud, lutning, relativ altitud, avstånd till sjöar/hav, avstånd till vattendrag, avstånd till lineament, avstånd till nodpunkter, bergarter, jordarter, dräneringstäthet, avstånd till geologiska övergångslinjer, jorddjup och TWI). Resultaten från korrelationstester för Kendalls tau var mellan 0,06-0,13 och för Spearmans rho mellan 0.09-0.19, samt en total noggrannhet på 52-55 %. Positiva men låga värden för Cohens kappa indikerade att alla beräkningar överträffade slumpen, men inte med marginal. Beräkningar av VIP (Variables importance on PLS projektion), utifrån PLS (Partial Least Squares) identifierade altitud, jordart, dräneringsdensitet och TWI som de mest inflytelserika indikatorerna för analysen.  Slutsatserna i denna studie var bland annat att GRP-metodiken hade låg prediktionsförmåga som sannolikt berodde på de svaga sambanden mellan indikatorerna och den specifika kapaciteten. De svaga sambanden kunde också bero på att specifik kapacitet har svagheter som valideringsvariabel för grundvattenresurspotential, kopplat till hur kapaciteten mätts vid brunnsborrning. Studien visar att en vidareutveckling av viktningsmetodiken genom att integrera PLS skulle vara fördelaktigt, eftersom PLS beräknar indikatorernas varians utifrån den specifika kapaciteten, istället för att anta sambandet som PCA.

This thesis argues for an approach which goes beyond the conventional urban climate governance view. With engagement in social-technical practices, a more sustainable and inclusive way of transforming the city can be accomplished. One way of doing so is with the offering of the urban living lab as a playground for real-life experiments. With a purposive intervention in an urban socio-technical system, the three- dimensional concept of urban environmental governance, socio-technical experiments and strategic experiments with designed policies can create a more sustainable urban transition. The urban electric vehicle transition is just one example of how these three concepts can be applied. In order to demonstrate the interaction of a sustainable urban transition, an empirical case study was conducted.   This thesis makes a conceptual contribution by engaging with current understanding of urban sustainability transition, using the urban electric vehicle transition as a reference point. The insights of this study extend the theories of the socio-technical system and argue that it is not only about social and technological innovation but how multiple innovations are experimented with and combined in an existing urban context. In addition, the research addresses how this transition is governed on a municipality level and is achieved through a multiple case study approach, analysed through the lens of environmental governance and offers an empirical exploration and develops the theoretical and conceptual framework of the socio-technical system further.

Marine sulfide – bearing sediments that oxidize when in contact with oxygen and leach outelements in high concentrations to small watercourses have been a problem for many years allover the world especially around the Bothnian Bay. The purpose of this study was to furtherinvestigate the sulfur mineralogy present in acid sulfate soils in the area of Luleå, Sweden. Asecondary aim was to see if elements leach out and accumulate in an acid sulfate soil closer tothe recipient. Samples were taken in two profiles (one oxidized and one waterlogged) fromfour sites (sites A-D) and were analyzed for whole rock geochemistry. Two sites were furtherinvestigated for mineralogy in polished samples with an optical microscope, Ramanspectroscopy and SEM-EDS. Each profile consisted of three layers: oxidation zone, transitionzone and reduced zone. The oxidation zone above the groundwater table was light grey withbrown iron hydroxide staining. Parts that lied under the water table were dark grey-black within general strong odor (“rotten eggs”) due to its sulfur content. It was usually straightforwardto distinguish and separate the layers from each other directly in the field, however in somecases pH was needed for confirmation.A general feature of investigated polished samples is the presence of abundant framboidalpyrites that are common in reduced marine sediments. The transition zone was formed in suboxicconditions and this feature is reflected by the mineralogy. Many morphologies of theframboidal pyrite were observed in this layer and signs of both dissolution and formationoccur. In the sample from site C one could observe elemental sulfur in form of large (up to 50μm) euhedral crystals. In the samples with pH<4, no sulfides occur as they have been replacedby jarosite (site B). Site C lacks these sulfur-bearing hydroxides which is thought to be due toa sulfur concentration of <0.2 %. Sulfur shows extensive leaching at most sites but at site B andD1, it accumulates in the transition zone. Elements like cobalt (Co), nickel (Ni) and zinc (Zn)are leached out or are accumulated further down in the profile. Elements that could have beentransported and have accumulated in the waterlogged profiles are Co, Ni, Zn and chromium(Cr) and in some profiles also copper (Cu) and vanadium (V). / Coastal watercourses in Bottenviken: Method development and ecological restoration- A cross-border Swedish-Finnish cooperation project

La connaissance de la composition en hydrocarbures des gisements pétroliers est un enjeu majeur afin de déterminer la faisabilité et l’intérêt de l’exploitation de leurs réservoirs. La présence des gaz acides et des composés corrosifs peut marquer la différence entre un projet d’exploitation qui sera développé et un autre qui sera considéré comme non viable. Dans ce contexte la présence de H2S joue un rôle majeur, du fait de sa toxicité et des investissements nécessaires pour séparer le H2S, ainsi que pour réduire la concentration des composés soufrés aux valeurs requises par la législation. Bien qu’il soit accepté que les concentrations élevées en H2S dans les réservoirs carbonatés de pétrole sont issues des réactions entre les hydrocarbures et les ions sulfates (SO42-) en phase aqueuse, l’influence de H2S sur le craquage des hydrocarbures et la formation des composés soufrés est peu connue. Dans le cadre de cette thèse, l’influence de H2S sur le craquage des hydrocarbures aromatiques dans les conditions des réservoirs pétroliers a été mise en évidence par l’étude de la maturation artificielle par pyrolyse confinée d’un composé modèle, le n-butylbenzène, en présence et en absence de H2S. Ainsi, le n-butylbenzène pur, et le mélange n-butylbenzène – H2S ont été pyrolysés dans les capsules en or à des températures entre 310 °C et 350 °C à pression constante de 700 bar pour des durées comprises entre 3 et 15 jours. Les résultats de la pyrolyse du n-butylbenzène pur ont permis la construction et la validation d’un modèle cinétique détaillé dont l’extrapolation aux températures et pressions géologiques (200 °C, 700 bar) montre que le temps de demi-vie moyen du n-butylbenzène est similaire à celle des alcanes. Certaines voies de formation des produits soufrés majeurs par les interactions entre le n-butylbenzène et le H2S, des thiols et des phénylthiophènes, ont été proposées faisant ressortir l’importance de la réactivité de la chaîne aliphatique sur le craquage des composés alkyl-aromatiques dans les conditions expérimentales. La comparaison entre les deux systèmes expérimentaux en présence et en absence de H2S a montré aussi l’effet accélérateur de H2S sur le craquage de n-butylbenzène, et par extrapolation, sur le craquage des composés alkyl-aromatiques à chaîne aliphatique longue dans les conditions de pyrolyse / Understanding of hydrocarbon composition in oil reservoirs is a major issue in order to assess the feasibility and the implications of further extraction of buried resources. The presence of acidic gases as well as corrosive compounds can make the difference between an extraction project that will be developed and another that will be considered as unsustainable. In this context, the presence of H2S plays a major role, due to H2S toxicity and the economic investments needed to separate it and to reduce the concentration of related sulfur compounds to permitted levels required by current legislations. Although it is known that high concentrations in carbonate oil reservoirs are produced by the reaction between hydrocarbons and sulfate ions (SO42-) in the aqueous phase, the influence of H2S on petroleum cracking and on the formation of sulfur compounds is little known. In this thesis, the influence of H2S on the cracking of aromatic hydrocarbons under oil reservoir pressure and temperature conditions was studied by confined pyrolysis artificial maturation of a model compound (n-butylbenzene) with and without presence of H2S. Thus, the pure n-butylbenzene and the n-butylbenzene-H2S mixture were pyrolyzed in the gold capsules at temperatures between 310 °C and 350 °C at a constant pressure of 700 bar for periods from 3 to 15 days. The results of pure n-butylbenzene pyrolysis allowed the construction and validation of a detailed kinetic model whose extrapolation to geological temperatures and pressures (200 °C, 700 bar) shows that the average half-life of n-butylbenzene is similar to that of alkanes. Some formation pathways of the major sulfur-containing compounds H2S (thiols and phenylthiophens) produced by interaction between n-butylbenzene have been proposed. These formation pathways highlight the control of the aliphatic chain reactions on the cracking of the alkyl-aromatic compounds at the experimental conditions of this study. Comparison of the two experimental systems in the presence and absence of H2S also exposed the accelerating effect of H2S cracking on n-butylbenzene and long-chain alkyl aliphatic compounds under pyrolysis conditions

Bicycling has many advantages. For example, it emits less noise compared to motor vehicles, it is environmentally friendly, and bicycling, as a means of transport, gives people exercise. To encourage bicycling in Sweden, the Swedish government has promoted policies and proposals on national and local levels. At the same time, several pieces of research on bicycle use in Sweden show that more people are bicycling now than 60 years ago. STRADA’s (Swedish Traffic Accident Data Acquisition) reports also show that most people who are severely injured in traffic are bicyclists, and that most bicycle accidents occur in urban and metropolitan areas.   Stockholm is a European city with a growing population. At the end of 2013 the population were 897 700    and it is predicted to grow by 25 % by 2030. The municipality of Stockholm is working on investment projects for bicyclists with the aim to increase accessibility and road safety such as special road safety measures at intersections that often aim at improving road conditions for both pedestrians and bicyclists, and better maintenance of bicycle paths, both in summers and winters. Critics and different debate articles about bicyclists` safety and accessibility point out that the investments that Stockholm municipality is making are not enough for meeting the growing population, especially for bicyclists.   The aim of this study is to analyse the causes of bicycle accidents in the city of Stockholm. To help answer the research questions stated below, statistics on bicycle accidents were extracted in Excel from Strada and compiled in Excel using the Excel tool PivotTable and Analysis Tool Pak. The questions investigated in the thesis are as follows: when and where are bicyclists most likely to suffer an accident, why does the accident occur, and what causes are behind bicycle accidents at the chosen place of investigation? Five categorisations on the causes of single bicycle accidents were used and these were: operations and maintenance, road design, bicycle interactions, cyclists’ behaviour and conditions, and interaction with other road users.    In addition to the above, a semi-structural qualitative interview was conducted with bicyclists who bicycle in or along the report's area of investigation. The results of this report show that single bicycle accidents in the investigated area have increased between 2010 and 2016, and that many bicyclists are not satisfied with the bicycle infrastructure in Stockholm.

Made available in DSpace on 2014-06-11T19:32:19Z (GMT). No. of bitstreams: 0 Previous issue date: 2008-01-17Bitstream added on 2014-06-13T20:03:42Z : No. of bitstreams: 1 sayeg_hs_dr_rcla.pdf: 3535019 bytes, checksum: a38e98172ed9f1310d44aef93596cf8b (MD5) / Fotografia aérea NADIR é um conceito usado rotineiramente por geólogos e pesquisadores de vários campos de atividade. Filmagem aérea de baixa altitude, em perspectiva ou ortogonal, é um recurso muito acessível, pela qualidade e relação custo-benefício dos equipamentos digitais disponíveis, pela capacidade de processamento e facilidade de operação dos softwares e hardwares lançados no mercado e pelo custo da hora de vôo em aviões de pequeno porte. A visualização da organização das paisagens através de filmagens aéreas em perspectiva permite a construção de um banco de dados de fácil manuseio e fornece um ponto de vista complementar às informações derivadas de outras fontes. Os estudos e ações efetuados buscaram explorar essa técnica de registro de dados e testar seu potencial para compor material didático e transmitir informações específicas de interesse geológico. / Vertical aerial videography is a commonly technique used by geologists and researchers from several fields of knowledge. Aerial videography of low altitude, in oblique viewing, is a resource not spread, but very accessible, by the quality of digital equipment available, by capacity and facility of software and hardware operation and by the low cost of flight hour in small planes. The terrain observation (imaging) and oblique visualization of landscape in TV language allow building data base, to promote discrimination of surface landforms and morphologic patterns with tectonic meanings, and supply an approach that supplement the information derived from other media. In this work the goal was to apply this technique of data register in low cost and complexity of data treatment, test its aptitude to compose the didactic material and transmit specific information from geological interest.

The tropical hardwood forests of south Florida persist as well-drained patches of broadleaf forest separated by brackish water swamp, marsh, or pineland. In this dissertation, a functional trait approach was used to understand the structure and dynamics of these communities and their responses to abiotic and biotic variation. Twenty-seven permanent plots (20 x 20 m2) were established across the south Florida landscape, representing four sub-regions: Everglades marsh, Long Pine Key, Upper Keys, and Lower Keys. Community weighted mean trait values for four of six selected traits showed significant inter-sub-regional variation. Out of them, three traits (specific leaf area, tree height, and leaf phosphorus) increased significantly from dry and low productivity Florida Keys in the south to the moist and productive areas on the south Florida mainland, while wood density showed the opposite pattern. Trait variance ratios (T-statistic metrics) was used to explore internal filtering (processes that operate within a community) and external filtering (processes that operate at larger scale than that of the individual population or community) on community structure. Both external and internal filtering in the functional composition of south Florida hardwood hammock forest were important for local communities differing in freshwater accessibility, or that occupy different positions along strong edaphic or climatic gradients. To understand the underlying mechanisms that drive species assembly during forest succession in Florida dry sub-tropical forest, 13 leaf, stem, reproductive, and architectural traits of resident tree species across the successional gradient were measured. Tests of null models showed that younger communities are shaped by environmentally driven processes, while mature communities are shaped by competitively driven processes. The overall trait similarities among species present in North Key Largo tropical dry forest suggest that tree species are specialists on the local environment, and their ability to survive and grow in a stressful environment may be more important than competition for resources at larger scale. Moreover, tree species in these forests may exhibit specialization or trait plasticity in coping with drought by changes in their stomatal morphology or activity, allowing for a balance between gas exchange and water loss in a periodically stressful environment. A significant negative correlation between stomatal density and size, and a positive correlation between leaf δ13C and stomatal density were observed across habitat gradient for one of the dominant hardwood hammock species (Bursera simaruba). Small and densely distributed stomates in tandem seems to represent a strategy that allows hammock species to conserve water under physiological drought. Furthermore, findings from this work also showed both intra- and inter-specific trait variation at regional and local scales influence community assembly patterns in hardwood hammock communities in South Florida.