Dams are man-made structures that in order to keep functioning and to be considered structurally healthy need constant monitoring. Assessing the deformation of dams can be time consuming and economically costly. Recently, the technique of Interferometric Synthetic Aperture Radar (InSAR) has proved its potential to measure ground and structural deformation. This geodetic method represents a cost-effective way to monitor millimetre-level displacements and can be used as supplemental analysis to detect movements in the structure and its surroundings. The objective of this work is to assess the practicality of the method through the analysis of the surface deformation of the Ajaure dam located in northern Sweden, in the period 2014-2017, using the freely available Sentinel-1A images. The scenes, 51 in ascending and 47 in descending mode, were processed exploiting the Persistent Scatterer (PS) technique and deformation trends, and time series were produced. Built in the 60’s, the Ajaure embankment dam is considered as high consequence, meaning that a failure would cause socio-economic damages to the communities involved and, for this reason, the dam needs constant attention. So far, a program of automatic measurements in situ has been collecting data, which have been used partly to compare with InSAR results. Results of the multi temporal analysis of the limited PS points on/around the dam show that the dam has been subsiding more intensely toward the centre, where maximum values are of approximately 5 ± 1.25 mm/year (descending) and 2 ± 1.27 mm/year (ascending) at different locations (separated of approximately 70 m). Outermost points instead show values within -0.7 and 0.9 mm/year, describing a stable behaviour. The decomposition of the rate has furthermore revealed that the crest in the observation period has laterally moved toward the reservoir. It has been observed that the operation of loading and unloading the reservoir influence the dam behaviour. The movements recorded by the PS points on the dam also correlate with the air temperature (i.e. seasonal cycle). The research revealed that the snow cover and the vegetation could have interfered with the signal, that resulted in a relative low correlation. Therefore, the number of PS points on and around the dam is limited, and comparison with the geodetic data is only based on a few points. The comparison shows general agreement, showing the capacities of the InSAR method. The study constitutes a starting point for further improvements, for example observation in longer period when more Sentinel1 images of the study area are collected. Installation of corner reflectors at the dam site and/or by use of high resolution SAR data is also suggested.

The widespread degradation of permafrost-cored palsa mires due to global warming necessitates accurate quantification to estimate potential greenhouse gas (GHG) flux changes. This study utilized high-resolution Unmanned Aerial Vehicle (UAV) imagery to quantify palsa degradation dynamics, including lateral, vertical, and geomorphological changes in the Storflaket palsa mire in north-west Sweden. A GIS-based analysis of UAV-derived differential Digital Elevation Models (DEM) between 2016–2023 revealed subsidence on >99 % of the palsa, active lateral erosion, and thermokarst formation. Despite near-double marginal subsidence rates, interior degradation accounted for ~95 % of the total volumetric decrease, attributed to a substantially larger interior area. The mean height, area, and volume changes for the whole palsa were -43.28±7.33 %, -6.66±0.74 %, and -47.00±7.26 %, respectively. However, the large decreases in height and volume are likely overestimations. The geomorphological analysis revealed landform element changes in ~46 % of the palsa and indicated some level of predictability in these changes. The results suggest that palsa degradation induces pronounced local landscape variation, which, in combination with fragmentation, affects the degradation rate. Furthermore, geomorphological changes provide a warning of an impending increase in CH4 emissions at Storflaket. These findings highlight the importance of high-resolution remote sensing techniques to survey palsa degradation dynamics, which is essential to enhance the understanding of these processes and, in continuation, their contribution to GHG fluxes.

Marine geological surveys in Asköfjärden in the southern Stockholm Archipelago hasrevealed step like features in the sediments on the Baltic sea floor. The aim of this project is toanalyse the steps and possible formation processes from the survey data. The data used aretaken from the acoustic instruments multibeam echosunder and Chirp sonar sediment profiler.The multibeam reveal the seafloor topography and can detect water column features. TheChirp sonar produce sub-bottom profiles showing the sediments down to some tens of metersunderneath the sea floor. The multibeam data show multiple crescent shaped steps as well aselliptically shaped “pockmarks”. Water column data show what could be interpreted as seepsfrom the sea floor under these features. The sub bottom profile show deformation and fluidsignatures under the steps. Gas signatures and what could be other fluids are present. Theinterpretation concludes that the formation could be from either gas or groundwater seeps. Nodefinitive conclusions can be made from the data available for the present study, andapetrophysical or geochemical study of the study area cold provide further understanding ofthe formation of the steps.

Ståndort är ett område där ett bestånd av en viss växt finns, ofta avses träd inom skogsproduktion. Förutsättningarna för detta, ståndortsfaktorer, återfinns i markens egenskaper (edafiska faktorer) och klimatet. Dessa påverkar därigenom växtens produktion, något som särskilt är av intresse inom skogsbruket och de skogliga vetenskaperna. Till detta kommer att växter samspelar med andra växter och organismer såsom svampar, bakterier och djur, och även den antropogena påverkan med faktorer såsom husdjursbete, atmosfäriskt nedfall och skogsproduktion har en stark inverkan på vegetationen. Utifrån att studera några av de mer kända teorierna om växtsamhällen och -strategier samt olika vinklar av ståndortsfaktorer var hypotesen att det går att få fram en problematiserande bild och hitta störfaktorer (confoundingvariabler), som kan ge felaktiga tolkningar av resultat. Ett antal kända verk inom vegetationsklassificering gicks igenom, kompletterat med stödjande litteratur. En artikelsökning genomfördes också, med kombinationer av specifika sökord med anknytning till ståndort. För att begränsa urvalet och ge en mer regional prägel på arbetet ställdes sökfiltren i artikelsökningen in på att enbart visa resultat från Skandinavien och Finland. Artiklarna delades in efter teman och behandlades efter dessa. Även om få huvudsakliga faktorer styr vegetationen finns flera variabler som lokalt har en stor betydelse, såsom snö, genetiska egenskaper och symbios med andra organismer. Dessa variabler kan vara svåra att mäta och det finns mycket på detaljnivå som är dåligt undersökt. Markanvändningar påverkar de edafiska faktorerna långt efter att brukandet ändrats eller upphört, men detta har olika stor lokal påverkan. Kvävets och kolets halter och cykler är återkommande osäkerhetsfaktorer i artiklarna, där det atmosfäriska kvävenedfallet spelar en viktig men ojämn roll, och jämförbara mätningar försvåras av skillnader i väder och klimat. Till detta kommer påverkan av markorganismer, vilka har en mycket viktig del i växternas näringsupptag, men är svår att mäta. Även om alla aspekter av en växtplats inte kan tas med bör fler felkällor tas i beaktande och modeller ha möjlighet att kalibreras mot olika teorier om växtsamhällen och -strategier. Flera faktorer som traditionellt inte räknas som ståndortsfaktorer, såsom snödjup, symbios med markorganismer och markanvändning, kan vara betydelsefulla att ta med i exempelvis modellering. / A site is an area where a population of a specific plant species has its habitat, often the connotation is forestry. The prerequisites for this, the site indices (also site variables or stand variables), can be found in the characteristics of the ground (edaphic factors) as well as the climatic impact. These elements affect the growth and production, which is of interest in forestry and forest sciences. Upon this the plants interact with each other as well as with other organisms, i.e. fungi, bacteria and animals, and there is also an anthropogenic impact where factors such as livestock grazing, atmospheric deposition and forest production strongly affects the vegetation. By studying some of the more prominent theories on vegetation societies/sociologies and plant strategies, as well as different aspects of the site concept, the hypothesis was that a problematizing picture of site indices can be found and some confounding variables that can give erroneous interpretation of results. A number of major works in vegetation classification was gone through, supplemented by supporting literature. An article search was conducted to find journal articles, using combinations of specific search terms related to site indices. To narrow down the results and give a more regional touch to the thesis, the filter was set only to show results from Scandinavia and Finland. The articles were grouped into themes and handled theme-wise. Even though there are few principal factors controlling the vegetation there are a number of variables which locally can have a large impact, such as snow, genetic traits and symbiosis. These variables can be hard to measure, and a lot of things at a detailed level are poorly investigated. Land use modifies the edaphic properties long after the usage have changed or been discontinued. The amounts and cycles of nitrogen and carbon are recurrent uncertainties in the articles, where deposits of nitrogen from the atmosphere plays an important but uneven role and measurements can be hard to compare due to differences in weather and climate. Added to this, organisms in the ground have a major role in the plants’ nutrient uptake, but the effects can be hard to study. A concluding remark is that even though all aspects of a site cannot always be included more confounding variables could be taken in account and models should be able to be calibrated to different theories on vegetation societies/sociologies and plant strategies. Many factors normally not counted as site indices, i.e. snow depth, soil biota symbiosis, and land use, could be valuable to include in e.g. modelling.

Cette thèse traite des interfaces utilisateur tangibles (TUI). La première partie de ce manuscrit concerne l'interaction tangible sur table interactive. Nous introduisons tout d'abord les TUIs et les tables interactives. Nous validons une hypothèse concernant la spécialisation de la forme des interacteurs tangibles et nous en tirons les conséquences pour la conception des TUIs. Nous proposons une solution de boîtier à boutons pour y déporter certaines opérations dans le contexte d'une TUI sur table interactive. Nous abordons la construction et le développement d'un système de tables interactives tangibles transportables et à faible coût permettant de faire du prototypage rapide de TUIs. Nous terminons en soulignant les particularités de l'évaluation expérimentale des TUIs. La seconde partie de ce manuscrit traite un cas d'application d'une TUI pour les géosciences : GeoTUI. Nous commençons par présenter le contexte métier des géophysiciens et leurs besoins en terme de nouveaux moyens d'interaction. Nous présentons les résultats de notre conception d'une TUI pour les géosciences. Nous précisons le détail du développement de notre prototype. Pour terminer, nous présentons les deux expérimentations utilisateurs qui ont été conduites pour valider nos choix de conception. / This thesis focuses on tangible user interfaces (TUI). The first part of this manuscript is about tangible interaction on tabletop. We first introduce TUIs and tabletops. We validate an hypothesis about the specialization of the form of the tangible objects, and conclude from that consequences on TUIs design. We propose the solution of a button box to deport some operations in the context of tabletop TUI. We present the construction and development of a transportable and low cost tabletop TUI system that allows rapid TUI prototyping. We end pointing out the special features of user experiments of TUIs. The second part of this manuscript deals with an application case of a TUI for geoscience: GeoTUI. We start presenting the context of the geophysicists work and their need in term of new way of interation. We present the results of our design of a TUI for geoscience. We detail the development of our prototype. To finish, we present two user experiments we conducted to validate our design choices.

Ekobacken, Värmdö kommun, har problem med surt yt- och grundvatten med höga metallhalter. Uppmärksamheten har riktats mot berggrunden som krossats och lagrats i deponihögar. Bildningen av sur lak styrs av flertalet geokemiska egenskaper, bland annat vilka sulfidmineral som förekommer och deras kristallstruktur. Prover från Ekobacken har undersökts utifrån sulfidhalt, kristallarea för opaka mineral och surgörande potential för att kunna utröna om ett samband finns mellan kristallareafördelning och lakningsegenskaper. Proverna har mikroskopiskt undersökts i reflekterande ljus för att skilja ur vilka opaka faser som förekommer samt har tunnslip fotograferats för att bildanalysera de opaka faserna utifrån area och form. Ett statiskt laktest utfördes på proverna för att kvantifiera dess lakningsegenskaper. Resultatet visar att bergarterna bestod i stor del av kvarts, fältspat och biotit i olika fördelningar. Opaka faser som förekom var pyrit, grafit, kopparkis och magnetit. Bergarterna visade sig generellt ha hög sulfidhalt från ABA resultatet, där ett prov hade en halt på 0,61 vikt%, medan andra prov hade relativt hög bufferförmåga och därför ingen surgörande potential. Proverna som undersöktes visade sig vara likartade varandra i förhållande till kristallareafördelning av opaka faser och form. I den här studien gick ingen direkt korrelation mellan provens kristallareafördelning för opaka faser och lakningspotential att utröna / Ekobacken, Värmdö municipality, have a problem with acidic surface- and groundwater with high metal content. The attention has been directed towards the bedrock which have been crushed and stored in landfills. The production of acid drainage is controlled by multiple geochemical properties inter alia which sulphide minerals are present and the structure of crystals. Samples from Ekobacken has been collected and analysed for sulphide content, crystal-area of sulphide minerals and acidic potential to investigate if there is a correlation between crystal-area distribution and leachability. The samples were examined under reflective light microscopy to determine the different opaque phases present and the thin sections were photographed for a photo analysis regarding crystal area and shape. A static leachability test was performed to be able to quantify the samples potential to produce acidic drainage. The results show that the samples contained mostly quartz, feldspars and biotite. Opaque phases present were pyrite, graphite, chalcopyrite and magnetite. ABA results showed high sulphide content, where one sample reached 0,61 wt. % sulphide content. Other samples contained relative high ability to buffer acidic reaction and thus showed no potential to produce acidic drainage. The samples were homogenous to each other with regard of crystal-area distribution of opaque phases and aspect-ratio of individual crystals and in this study no direct correlation between the sample’s crystal-area distribution of opaque phases and potential to produce acidic drainage was apparent.

Global climate change is anticipated to raise the overall temperatures and is likely to increase future mortality attributable to heat. China, a rapid developing nation with the world’s largest population, has experienced noticeable changes in climate over the past century, with an annual increase in air temperature by 0.5–0.8°C. While increasing evidence is suggesting that climate change has posed significant health risks to Chinese population, including heat-related mortality, the extent to which climate change will affect future mortality and the sources of uncertainty in projecting prospective changes in mortality remain unexplored. This working-in-progress study aims at estimating excess future premature deaths in large urban areas in China resulting from potential increases in temperature under climate change and investigating sources of uncertainty. We include 51 large Chinese cities in this study, which approximately one third of the total population in China. We use an integrated approach, which combines temperature predictions from climate models, local temperature-mortality relationship and population forecasting, to project the future excess mortality attributed to higher temperature during warm season. The poster presents the results of predicting temperature change during 2040-2050 relative to the baseline period 1950-2000 in the 51 cities selected. We ensemble outputs from 19 climate models used in the IPCC 5th Report, including outputs related to all four AR5 emission scenarios (RCPs 2.6, 4.5, 6.0 and 8.5).

We analyzed soils in Alder Bald, Grassy Bald, and Rhododendron Bald communities on Roan Mountain to infer the influence of vegetation on soil and to help guide management strategies. In all vegetation types, soils were acid (pH = 4–5) sandy loams. We found vegetation-associated differences for organic content, cation exchange capacity, acidity, two plant macronutrients (K, Mg), and three cations (Fe, Na, Zn). We predicted that nitrogen compounds would be highest in the Alder Bald because Alnus viridis ssp. crispa (Green Alder) can harbor nitrogen-fixing bacteria. Organic content was highest at the alder-bald sites, ammonium was similar among vegetation types, and nitrate was high at only some sample sites. The unique soil properties of the Alder Bald community, its likely role in primary succession, and its documentation as a long-standing community type on Roan Mountain suggest that management should be directed towards its conservation.

No description available.

Der ehemalige Salzbergbau im Raum Staßfurt führt seit dem 19. Jahrhundert zu Subrosion und teils bruchhaften Deformationen und damit verbundenen Senkungen und Vernässungen im Stadtgebiet. Im Rahmen eines Forschungsverbundvorhabens unter Federführung der BGR sollen in dieser Arbeit die grundlegenden strömungsdynamischen Prozesse im Salinar und Deckgebirge der betroffenen geologischen Formationen aufgeklärt werden. An Bohrkernen aus den entsprechenden Bereichen werden Durchflussexperimente durchgeführt und die Fluiddynamik im Inneren der Proben mittels Positronen-Emissions-Tomographie dreidimensional dargestellt. In Kooperation mit der Bundesanstalt für Materialforschung- und prüfung Berlin und dem Geologischen Institut der Johannes-Gutenberg Universität Mainz werden diese PET-Messungen der Fluiddynamik mit hochauflösenden computertomographischen Messungen der internen Struktur der Proben in Übereinstimmung gebracht. Die beobachteten Fließmuster sollen mittels einer Lattice-Boltzmann-Simulation nachvollzogen und dadurch das grundlegende Verständnis der Strömungsdynamik in diesen Gesteinen erweitert werden. Langfristig soll dies zu einer Verbesserung des Verständnisses der Grundwasserdynamik auf regionaler Ebene führen.