The geomorphological impact of small fossorial mammals (adapted to digging and living underground), such as rodents can be significant, and both their direct and indirect effects may contribute to landscape formation. This thesis is based on empirical field studies of two burrowing rodent species in sub-polar environments, namely invasive House mice (Mus musculus) on sub-Antarctic Marion Island and Norwegian lemmings (Lemmus lemmus) in sub-Arctic Abisko. The spatial distribution, sediment displacements, impact on vegetation and microclimatic effects of the rodents are documented. Invasive mice and rats, introduced on sub-Antarctic Islands during the 19th century, lack natural enemies and are shown to have a significant direct and indirect geomorphic impact by direct sediment displacement, vegetation removal by burrowing, grazing and trampling and thereby exposing the sediments for rain, wind and frost processes.  The geomorphic impacts of lemmings are comparatively more limited as they rely on natural hollows and snow cover for protection and do not burrow to the same extent as other fossorial rodents in cold regions. Lemmings are thus suggested to have little impact on landform integrity, but can affect vegetation composition. A comparison of the findings from this study with published data on seven other rodent species and other physical mass transfer mechanisms in sub-polar and alpine environments suggests that fossorial rodents are a significant and sometimes dominant geomorphic force in sub-polar and alpine environments. The geomorphic work by ground squirrels, ice rats, plateau pikas and zokors is shown to be in the same order of magnitude as solifluction and rock falls. In alpine and periglacial environments these rodents are considered to act as key-stone species and ecosystem engineers through the creation of landforms by  dislocation and of soil and other impacts on soil properties, vegetation and ecosystem function

Quartz and pyrite samples from Pliocene-recent, sub-economic orogenic gold mineralisation in the Southern Alps and Mesozoic economic deposits in the Otago Schist Belt have been analysed for noble gases and halogens. Palaeo-hydrothermal fluids preserved in fluid inclusions were released by crushing and analysed by mass spectrometry. Helium isotope measurements confirm the absence of a mantle-derived fluid component in gold-bearing veins from the Southern Alps and at the large gold deposit at Macraes in Otago. A possible minor mantle helium component is observed in veins within 10km of the Alpine Fault that do not contain gold. Halogen ratios support the absence of mantle-derived fluid and support the presence of a crustal fluid derived from sediments, indicated by high I/Cl ratios. Mixing trends between 40Ar/36Ar and Cl/36Ar indicate mixing between a meteoric-derived fluid or air and crust-derived fluid in all sample types. A correlation between 40Ar/36Ar and 132Xe/36Ar shows that xenon is also sourced from the crustal fluid. Despite a strong crustal-radiogenic Ar signal in some samples, measured neon isotope ratios are atmosphere like. Noble gas elemental ratios show strongly fractionated 20Ne/36Ar away from air-saturated water and air values in deeper formed veins, suggesting air contamination is not dominant. Evidence for the presence of a significant trapped vapour phase is provided by calculated noble gas concentrations in water. Formation of this vapour phase using a two-stage model of de-gassing of meteoric water, and subsequent partial re-dissolution by a Rayleigh fractionation process could account for fractionated 20Ne/36Ar and atmospheric neon isotope ratios. In the Southern Alps, three main types of mineralisation can be identified by noble gas and halogen properties. Deep forming veins contain the most gold and are characterised by 20Ne/36Ar greater than air, 132Xe/36Ar ratios up to 75 times the air value, indicating metamorphic and meteoric fluid components. Some deep ankeritic type veins that display evidence of a CO2-rich component fluid show the highest 20Ne/36Ar ratios. Shallow, late veins have 20Ne/36Ar between air-saturated water and air values, and lower xenon and iodine contents. These veins formed from a boiling rock-exchanged meteoric fluid with a minor metamorphic fluid component and contain less gold. The characteristics of the Nenthorn deposit in Otago are similar to those of the shallow Alpine veins. The economically significant Macraes deposit possibly formed from a meteoric component and a strong metamorphic fluid component derived from the original sediments. This is indicated by the highest levels of excess xenon (relative to air) determined in this study. There is some potential for xenon to be used to fingerprint gold bearing fluids sourced from similar metasedimentary piles in orogenic belts.

La recherche en anthropologie biodémographique effectuée sur les communautés de Chiomonte(Haute Vallée de Suse), de 1670 à 1929, et de L’Argentière-la-Bessée (Hautes-Alpes), de 1690 à1889, a permis d’analyser les changements survenus tout au long de ces siècles pour ces deux pays.L’analyse des naissances a permis d’avoir un tableau général des deux populations, pouvant êtreinterprété tant au niveau biologique-démographique qu’au niveau économique-culturel.L’analyse des décès a mis en évidence l’importance des facteurs environnementaux sur l’évolutionde la mortalité, même si l’on peut reconnaître que, grâce à l’amélioration des conditions de vie, il ya eu une diminution du taux de mortalité infantile et infanto-juvénile ainsi qu’une augmentationprogressive des décès des personnes âgées.La culture, la société, l’économie et la religion sont les facteurs les plus importants qui influencentle comportement matrimonial; mais l’environnement aussi a joué un rôle important.La reconstruction des familles de Chiomonte nous a permis de constater que les changements auniveau économique et social qui se sont produits entre 1670 et 1830 ont eu des répercussions,quoique de manière différente, sur les aspects relatifs à la structure et à la descendance des familles.L’augmentation de la duré de la vie a produit une augmentation de la durée des mariages et ladécroissance de la mortalité infantile a déterminé un accroissement du nombre d’enfants quiatteignent l’âge reproductif. Restent, par contre, relativement constants l’âge des conjoints à leurpremier mariage, le nombre d’enfants l’intervalle protogénésique ainsi que l’intervalleintergénésique. / The research on biodemographical anthropology worked out on the community of Chiomonte(Haute Vallée de Suse), from 1670 to 1929, and of L’Argentière-la-Bessée (Hautes-Alpes), from1690 to 1889, has allowed the analysis of the changes in the periods considered in these twocountries.The analysis of births has worked out an overall view of the two populations both from a biologicdemographicperspective and from and economic-cultural one.The analysis of deaths has highlighted the importance of environmental factors on death, although ithas been possible to define that through better conditions of life, infantile and juvenile mortality ratecould decreased as well as old aged people mortality increased.Culture, society, economy and religion are the main factors which influenced marriage behaviors ;also environment played an important role.Families’ reconstructions in Chiomonte enabled us to understand that economical changes whichoccurred from 1670 and 1830 had different consequences on the structure and the lineage of thefamily. The increase of life time led to an increase of marriages and at the same time the decrease ofinfantile mortality determined the rise of children who reached the reproductive age.On the other hand, the age of partners at their first marriage, the number of children, theprotogenesic and intergenesic intervals remain constant.

Alla ska ha lika stor möjlighet att utöva idrott på lika villkor. Parasport är idrott till för personer med någon form av funktionsnedsättning såsom synnedsättning, intellektuell funktionsnedsättning eller rörelsenedsättning. Inom parasport finns alpin skidåkning som går ut på att ta sig ned för backen så snabbt som möjligt i en utstakad bana. Utbudet av professionell utrustning för både alpint och andra sporter som är möjlig att individanpassa mot idrottsutövarens behov är mycket begränsad om än inte obefintlig. Projektet initierades av landslagstränaren för alpina parasportförbundet, Henrik Bergqvist. Syftet med detta projekt är att möjliggöra en bättre tackling av en slalomkäpp för paraalpinåkare med förkortad underarm. Målet med projektet är att ta fram ett konceptunderlag för att kunna tillverka ett alpint slalomarmskydd. Konceptunderlaget kommer innefatta tredimensionella ritningar för produkten samt materialval och tillverkare. Denna rapport omfattar en produktutvecklingsprocess innehållande fem faser, förstudie, produktspecificering, konceptgenerering, utvärdering och val av koncept, prototyp och detaljkonstruktion. Resultatet av projektet genererades i ett konceptunderlag för ett slalomarmskydd till paraalpinåkare med förkortad underarm. Detta koncept har funktionen att tackla bort slalomkäppen samtidigt som den ska vara ergonomisk mot underarmen, och ha ett material som tål de påfrestningar som skyddet kommer utsättas för. Projektet och dess resultat överlämnas till uppdragsgivaren med goda förutsättningar att vidare kunna tillverka detta slalomarmskydd. / Everyone should have an equal opportunity to practice sports on equal terms. Parasport is sports for people with some form of disability such as visual impairment, intellectual disabilities or mobility impairment. In parasport, there is alpine skiing that involves getting down the slope as quickly as possible in a marked course. The range of professional equipment for both alpine and other sports that can be individually adapted to the athlete's needs is very limited, although not non-existent.   The project was initiated by the national team coach for the alpine parasport association, Henrik Bergqvist. The purpose of this project is to enable a better tackle of a slalom gate for para-alpine skiers with a shortened forearm. The goal of the project is to produce a concept material to be able to manufacture an alpine slalom arm guard. The concept material will include three-dimensional drawings for the product as well as material selection and manufacturers.   This report covers a product development process that includes five phases, feasibility study, product specification, concept generation, evaluation and selection of concepts, prototype and detailed design.   The result of the project was generated in a concept data for a slalom arm protection for para-alpine skiers with a shortened forearm. This concept has functions to tackle the slalom gate while at the same time being ergonomic against the forearm and having a material that can withstand the stresses to which the protection will be exposed.   The project and its results are handed over to the client with good conditions to be able to further manufacture this slalom arm guard. / <p>Betyg 2021-07-16</p>

Understanding biological responses to climate change is a primary concern in conservation biology. Of the ecosystems being rapidly impacted by climate change, those in the high-elevation tropics are among the most poorly studied. The tropical Andean biosphere includes record elevations above 5000 meters, where extreme environmental conditions challenge many organisms. In the Cordillera Vilcanota of southern Peru, frogs including Pleurodema marmoratum and Telmatobius marmoratus have expanded their ranges to 5244 – 5400 m into habitats created by glacial recession, making them among the highest recorded amphibians on Earth. To understand how hydrologic alterations from loss of glacial meltwater and climatic fluctuations affect these amphibians, I conduct a 36-month field study of reproductive phenology and develop a method to distinguish glacial meltwater-fed ponds and precipitation-fed ponds utilizing natural variation in stable isotopes of water (18O, 2H, and d-excess). My results suggest that some ponds critical for breeding populations may have lost their connection to glacial runoff. Ongoing deglaciation may transform these ponds from permanent to ephemeral habitats, leading to the extirpation of the fully aquatic species, T. marmoratus. The 2015/2016 El Niño delayed the onset of the 2015 wet season and shortened the P. marmoratum breeding and tadpole development period in ephemeral ponds. I examine regional patterns of amphibian occupancy and prevalence of the deadly amphibian pathogen Batrachochytrium dendrobaditis in unexplored high-elevation zones that were until recent decades covered by permanent ice. Next, I examine adaptive strategies that allow these two frog species to persist in the harsh high-elevation environment. Pleurodema marmoratum withstands the daily freeze-thaw cycle by utilizing a wide thermal tolerance range (from below 0ºC to CTmax > 32ºC) and I report the first evidence of frost tolerance in a tropical frog. My research compares divergent strategies allowing two anuran species to persist through disease and variable, extreme conditions in high-mountain environments, providing a better understanding of responses to and consequences of climate change for some of the world's highest life forms.

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La biodiversité et le fonctionnement des écosystèmes sont des propriétés écologiques essentielles qui ont une incidence sur le bien-être humain. Des études sur la manière dont les deux biens sont affectés par les activités humaines et par le changement climatique fournissent les connaissances indispensables pour orienter la gestion des ressources naturelles. Les données de rétroobservation à long terme permettent de reconstituer l’histoire environnementale passée et offrent d’excellentes opportunités d’acquérir de telles connaissances. L'ADN sédimentaire est un outil émergent permettant de reconstituer la biodiversité passée détaillée au niveau du bassin versant, grâce à son excellente résolution taxonomique et à ses origines très localisées. Cependant, les études antérieures basées sur l'ADN sédimentaire utilisaient rarement le riche arsenal de méthodes d'analyse écologique numérique existantes, développées pour différents types de données écologiques. Dans la présente thèse, nous avons examiné les applications potentielles de telles méthodes sur des études basées sur l'ADN sédimentaire. Avec plusieurs exemples d’études, nous avons montré comment ces méthodes peuvent optimiser les connaissances acquises lors de l’analyse d’ensembles de données multiproxy comprenant des enregistrements sédimentaires d’ADN, de sédimentologie et climatiques. Malgré certaines limitations, l’analyse numérique basée sur l’ADN sédimentaire combinée aux enregistrements de proxies traditionnels est un outil puissant pour démêler les interactions complexes écosystémiques. Les futurs progrès méthodologiques dans l'analyse de l'ADN et les méthodes numériques sont prometteurs pour fournir une compréhension inestimable sur les facteurs de changement de la biodiversité et du fonctionnement des écosystèmes à grande échelle spatiale et temporelle. / Biodiversity and ecosystem functioning are crucial ecological properties that impact human welfare. Studies on how both properties are affected by human activities and by climate change provide indispensable knowledge to guide natural resource management. Long-term retro-observational data allow to reconstruct past environmental history and offer excellent opportunities to gain such knowledge. Sedimentary DNA is an emerging tool to reconstruct detailed past biodiversity in catchment level, thanks to its excellent taxonomic resolution and highly localized origins. However, previous studies based on sedimentary DNA rarely utilized the existing rich arsenal of numerical ecological analysis methods, which are developed for various types of ecological data. In the present thesis we reviewed the potential applications of such methods on sedimentary-DNA-based studies. With several example studies, we showed how these methods can maximize the knowledge gained from the analysis of multiproxy datasets that included sedimentary-DNA-, sedimentological- and climate records. Despite some limitations, numerical analysis based on sedimentary DNA combined with traditional proxy records is a powerful tool to unravel complex ecosystemic interactions. Future methodological advancements in both DNA analysis and numerical methods are promising to provide invaluable understanding over the drivers of changes in biodiversity and in ecosystem functioning across large spatial and temporal scales.

Les grandes quantités de sédiments transportés par suspension dans les rivières alpines sont associées à d’importantes problématiques socio-économiques et environnementales telles que le transport de polluants, la dégradation des milieux aquatiques ou l’envasement des retenues hydroélectriques. Pour faire face à ces enjeux, il est nécessaire de mieux comprendre le rôle joué par le lit des rivières alpines sur la dynamique de ce transport. A partir de larges bases de données issues de la littérature et de nouvelles mesures de terrain, la première partie de cette thèse propose une étude à une échelle régionale de i) l’influence de la configuration des sources sédimentaires sur la variabilité du transport solide par suspension, ii) l’estimation de la quantité et de la disponibilité des particules fines dans le lit des rivières alpines et iii) l’analyse de la relation entre transport solide par suspension et mobilité du lit de ces rivières. Ces analyses montrent que la configuration du bassin versant en amont du point d’observation contrôle significativement la dynamique du transport solide par suspension observée en aval. De grandes quantités de sédiments fins sont en effet stockées dans les rivières alpines alluviales et il est ainsi possible de prédire une partie significative de leurs flux en suspension pour les forts débits à partir d’une modélisation de la mobilité de leurs lits. La seconde partie de la thèse teste ces résultats à une échelle locale. Pour cela, une campagne de mesures a été réalisée durant une saison complète de fonte sur un cours d’eau alpin typique, la Séveraisse. Un large panel de mesures directes et indirectes a été mis en œuvre pour mesurer la suspension, le charriage et les évolutions topographiques sur un tronçon de 3.5 km. Ces mesures confirment que les particules fines transportées par suspension interagissent fortement avec le lit dans ce type de tronçon morphodynamiquement actif. Ce dernier peut être perçu comme une zone tampon intermédiaire contrôlée par le forçage amont sédiments-débit liquide ainsi que par la mobilité et la morphologie de son lit. / The large quantities of sediments transported as suspension in Alpine rivers are associated with important socio-economic and environmental issues such as pollutant transfer, aquatic habitat degradation or dam siltation. To address these issues, it is required to better understand the role of Alpine river beds on the dynamics of this transport. In the first part of this thesis, we use large datasets from the literature and new field measurements to investigate at a regional scale i) the influence of sediment sources configuration on suspended load variability, ii) the quantity and availability of fine particles in Alpine river beds and iii) the relation between suspended load and river bed mobility. These analyses show that the catchment configuration upstream the observation point can significantly control the suspended load dynamics observed downstream. This first part also shows that large quantities of fine particles can be stored in alluvial Alpine rivers. For these rivers and for high flow rates, it was possible to predict a significant part of suspended load based on riverbed mobility modeling. The second part of the thesis tests these results at a local scale. To do so, an important field campaign was performed during the entire melting season of a typical Alpine river, the Séveraisse. A large panel of direct and indirect measurements was used to measure suspended load, bedload and topographic changes on a 3.5-km reach. These measurements confirm that suspended particles strongly interact with the river bed in that kind of morphodynamically active streams. The latter can be considered as an intermediate buffer controlled by the upstream hydro-sedimentary forcing and by the river bed mobility and morphology.

Plants adjust to challenging environments by genetically fixed changes and phenotypically plastic response. Alpine environments pose multiple challenges to plant life including cold, high irradiance and short vegetative period. To survive such specific conditions, plants often significantly alter their morphology. In my thesis I studied to which extent specific traits of alpine ecotypes repeatedly appear among independently formed alpine populations and to which extent these changes represent fixed genotypic differentiation vs phenotypic plasticity. To address these questions I performed an experiment in which Arabidopsis arenosa plants from sixteen populations belonging to two ecotypes (alpine and foothill) were grown in conditions resembling alpine vs foothill conditions. Specifically, I modified levels of irradiance and temperature and complemented alpine-like and foothill-like treatment by additional two extreme treatments to reach full-factorial design. I used discriminant and classificatory analysis to examine the overall morphological differentiation characterised by set of twenty measured traits. Then I examined variation in each trait by statistical Bayesian model that I designed for this purpose. I found out that although ecotypes are predominantly differentiated by fixed morphological...

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