• Refine Query
  • Source
  • Publication year
  • to
  • Language
  • 53
  • 51
  • 5
  • 4
  • 3
  • 2
  • 2
  • 1
  • Tagged with
  • 129
  • 56
  • 17
  • 15
  • 14
  • 13
  • 12
  • 11
  • 11
  • 10
  • 10
  • 10
  • 10
  • 9
  • 9
  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
61

The economics of Bagòss cheese production in Bagolino, Italy

Marletta, Piercarlo January 1900 (has links)
Master of Agribusiness / Department of Agricultural Economics / Vincent R. Amanor-Boadu / Many small communities in the Alps are facing the same problem of ensuring a durable economic development, protecting their natural resources and preserving their traditions under the constraints of higher production costs, distance from markets, isolation, severity of climate, a lower level of public services. This is the situation faced by Bagolino, a small town of roughly 4,000 inhabitants located in the Italian Alps. One of the major supporters to the growth of Bagolino, along with tourism, is its cheese Bagòss , whose origin dates back centuries. The Bagòss cheese is a semi-cooked cheese that is produced under strict processing methods that have been practiced for centuries. The Bagòss industry, with its unique organizational system, challenges researchers to investigate what factors are decisive in explaining its success. It is an example of a common situation in the Alps whose products arise from history, traditions and natural environment. This research aims to explain which factors influence the production of the Bagòss cheese and which factors explain differences among producers. Various aspects of interest of the Bagòss industry were examined through a literature review: social and economic situation of Bagolino and history of the town helped to get a better understanding of the background of the industry. The review of literature about entrepreneurship and supply chain was aimed to get a better understanding of the Bagòss industry organization; whereas theories about rural development and sustainable development described the social and environmental context of this production. Last the review of the main economic theories helped to analyze the Bagòss industry from the economic perspectives: monopolistic competition and the resource based view of the firm. Data were collected from multiple sources; the main source of data was a survey of farmers that involved all Bagòss producers. Data from administrative source were important for revision and also furnished data that could not be obtained from farmers. Qualitative interviews with experts were important for checking purposes and for understanding of the social and economic environment in which the Bagòss production takes place. Analytical tools of this thesis were of three different types: qualitative data used mainly to describe the growth medium of Bagòss and to formulate hypotheses to be tested with an econometric model. Statistical analysis provides a complete description of the industry. The Bagòss industry is not characterized by highly diversified use of the land: summer pastures, long term meadows and forests are the three main categories of the use of land. Almost all labor force is made up of family members and relatives. There are a total of 657 adult milking cows involved in the Bagòss production, with an average of 24.33 cows per farm; most farmers process all or part of their cow milk. The main product is the Bagòss cheese. We estimated the production at 146.5 tons of Bagòss. 69% of Bagòss is sold after aging for less than a year. In terms of marketing the most important channels are Bagolino’s retailers, consumers buying directly and retailers located outside Bagolino. According to our estimates EBITDA equals to 1,388 thousand Euro, an average of more than 55 thousand euro per farm. Two factors are able to explain most of the variability in the milk production: the number of workdays in the farm and the total cost of purchased feed. The EBITDA / tons of milk ratio is an indicator of the farm efficiency: the explanatory model for this is based on the operator’s age and level of education, the percentage of Bagòss sold after aging for one year or more, the percentage of Bagòss sold by direct sale to consumers and the size of the herd. Finally, a model able to explain the variability of the EBITDA / work days ratio was built; this ratio is considered to be an indicator of the labor productivity. This model is based on the percentage of Bagòss sold after aging for one year or more, the percentage of Bagòss sold to restaurants and hotels, the total milk production and the cost of rent of pastures. The first three have a positive impact on the dependent variable, whereas the fourth has a negative impact. The last two models show that small farms tend to be less efficient in their use of resources, and also less efficient in the use of labor.
62

Late Pleistocene Glacial Geology of the Hope-Waiau Valley System in North Canterbury, New Zealand

Rother, Henrik January 2006 (has links)
This thesis presents stratigraphic, sedimentological and geochronological results from valley fill and glacial moraines of the Hope-Waiau Valleys in North Canterbury, New Zealand. The findings demonstrate that a substantial portion of the modern valley fill comprises in-situ sedimentary sequences that were deposited during the penultimate glaciation (OIS 6), the last interglacial (OIS 5) and during the mid-late last glacial cycle (OIS 3/2). The sediments survived at low elevations in the valley floor despite overriding by later glacial advances. Sedimentologically, the fill indicates deposition in an ice marginal zone and consists of paraglacial/distal-proglacial aggradation gravels and ice-proximal/marginal-subglacial sediments. Deposition during glacial advance phases was characterized by the sedimentation of outwash gravels and small push moraines while glacial retreat phases are dominated by glaciolacustrine deposits which are frequently interbedded with debris flow diamictons. The overall depositional arrangement indicates that glacial retreat from the lower valley portion occurred via large scale ice stagnation. Results from infra-red stimulated luminescence (IRSL) dating gives evidence for five large aggradation and degradation phases in the Hope-Waiau Valleys over the last 200 ka. Combined with surface exposure dating (SED) of moraines the geochronological results indicate that glacial advances during OIS 6 were substantially larger in both ice extent and ice volume than during OIS 4-2. The last glacial maximum (LGM) ice advance occurred prior to 20.5 ka and glacial retreat from extended ice positions began by ~18 ka BP. A late glacial re-advance (Lewis Pass advance) occurred at ~13 ka BP and is probably associated with a regional cooling event correlated to the Antarctic Cold Reversal (ACR). The findings from the Hope-Waiau Valleys were integrated into a model for glaciations in the Southern Alps which uses data from a snow mass balance model to analyse the sensitivity of glacial accumulation to temperature forcing. Model results indicate that in the central hyperhumid sector of the Southern Alps ice would expand rapidly with minor cooling (2-4℃) suggesting that full glaciation could be generated with little thermal forcing. Some Quaternary glacial advances in the Southern Alps may have been triggered by regional climate phenomena (e.g. changes in ENSO mode) rather than requiring a thermal trigger from the Northern Hemisphere.
63

Matérialisations du souvenir en montagne : les enjeux identitaires des places et des placements / Materialising memory in mountains : place, placing and Identity

Petit, Emmanuelle 28 September 2012 (has links)
Cette thèse s’intéresse à un ensemble d’objets qui matérialisent différents types de souvenirs au sein des Alpes Occidentales. L’originalité de ces artefacts réside dans leur nature même : ils figurent tous l’idée de montagne sous diverses formes et pour différents motifs. Il s’agit tout aussi bien de monuments érigés au détour d’une rue ou sur une place centrale pour commémorer un exploit, une catastrophe ou l’oeuvre d’un homme en relation avec la montagne, que de stèles funéraires, profilées à l’image de sommets, érigées ça et là dans les cimetières, ou encore de plaques scellées à même le roc de la montagne.A partir d’une réflexion sur le façonnement de ces artefacts qui jouent avec la figure de la montagne, cette recherche interroge le rôle de l’espace dans les processus mémoriels et identitaires. Elle propose une lecture interobjective par l’identification, la spatialisation et la généalogie des différentes manières de mettre en scène le souvenir. Elle aborde également à partir de récits produits dans deux contextes spécifiques (Bessansen Haute-Maurienne (Savoie), Chamonix en Haute-Arve (Haute-Savoie)), selon une approche intersubjective cette fois, les relations que les hommes nouent avec ces artefacts, qu’ils vivent quotidiennement au contact de ces derniers ou qu’ils les contemplent de manière tout à fait occasionnelle. Cette démarche et ce terrain permettent de dégager les enjeux identitaires de la mise en visibilité des souvenirs et de souligner le rôle de l’espace dans ces processus.Cette thèse défend l’idée que les artefacts sont centraux dans l’établissement des rapports sociaux. Ils participent à la construction des mondes de chacun et jouent un rôle actif dans les relations à soi et à l’autre autour d’un ensemble de jeux d’échelles et de métriques. Les artefacts du souvenir seraient donc à la fois un ferment et un révélateur du fonctionnement identitaire de la société. Cette thèse vise alors à montrer qu’à partir d’un tout petit objet, il est possible de saisir de nombreux enjeux du fonctionnement de la vie en société, qui s’expriment entre autres par la recherche, l’octroi, la tenue, la défense d’une place. C’est en cela une invitation au développement d’une micro-géographie attentive aux individus, à ce qu’ils disent, à ce qu’ils font, et à ce qui légitime leur place, celle qu’ils veulent tenir et celle qu’on leur fait tenir, à travers les rapports sociaux qui se nouent et se dénouent autour de ces artefacts. / This PhD thesis considers objects materialising different kinds of memories in the Western Alps. Despite the great variety of these objects, they share a common specificity: they all enact the idea of mountain,through different shapes and for different reasons. They can be monuments along a trail, a road, a street or inthe middle of a central square in a city commemorating successful ascents, a mountaineering death, or the lifeof a mountain climber, or tombstones shaped like a mountain peak in a cemetery or commemorative plaques nailed on a mountains slope.Questioning the creation of such objects which are all designed in reference to the image of the mountain this research considers the role of spaces and places in identity-making and the process of remembering. I firstpresent an interobjective reading: identifying, spatializing and studying the genealogy of the different ways to showcase memory. Then I move on to an intersubjective reading: how do people in two specific contexts (Bessans in the Haute-Maurienne Valley, Savoie, France, and Chamonix, in the Haute-Arve Valley, Haute-Savoie, France) relate to these objects, whether they interact daily with them or only do so very occasionally ,when they happen to pass by them? This multi-face research method and the places where fieldwork took place have enabled me to understand the processes through which memory is made visible and the rolespaces and places play in such processes, as well as the identity issues linked to them.The central argument is that objects play a key role in the establishment of social relations. They helpto build inner-worlds and they play an active role in the relationships with oneself and with others, alongdifferent scales and different social relations to distance. Souvenirs, as objects of memory, are both the goadand the pointer to the production of identity in a society. From a very small object it is possible to graspseveral issues regarding how a society works, especially through the quest, the gift, the defence of a place.This PhD can be read as an invitation to develop a micro-geography attentive to individuals, to what they say, what they do, what legitimates their place ‑ the place they want to hold and the place they are put in ‑ and to the social relations that can fold and unfold through these objects.
64

Phylogenetic affinities, species delimitation and adaptive radiation of New Zealand Ranunculus : a thesis presented in partial fulfilment of the requirements for the degree of Doctor of Philosophy in Plant Biology at Massey University, Palmerston North, New Zealand

Lehnebach, Carlos Adolfo January 2008 (has links)
Ranunculus is the largest genus in the Ranunculaceae family and comprises c. 600 species. Its distribution is almost worldwide and the largest number of species occurs in temperate zones of North and South America, Europe, Asia, Australia, New Zealand, and in the alpine regions of New Guinea. In New Zealand the genus Ranunculus contains about 41 species and is found both in lowland and alpine environments. This thesis reports a phylogentic analysis of lowland and alpine New Zealand Ranunculus, an assessment of morphological variation and species boundaries among complex alpine species and examines evidence suggesting adaptive radiation of the alpine Ranunculus lineage. Phylogenetic analysis suggests that New Zealand species of Ranunculus are not a monophyletic group. For some New Zealand species the closest affinities inferred from the analysis of nrDNA and cpDNA sequences are to species from other land masses such as Australia, the Northern Hemisphere, southern South America and islands in the southern Oceans. Contrary to Fisher’s hypothesis (1965), the Andean South American Ranunculus in the section Trollianthoideae are not closely related to the New Zealand alpine group. The Trollianthoideae section was not monophyletic and the Peruvian-Ecuadorian species in it form a lineage sister to European alpine species. Instead, aquatic and sub-aquatic species from the Euro-Mediterranean region and southern South America and the Kerguelen Island were inferred as the closest relatives to the New Zealand alpine Ranunculus; albeit this relationship was weakly supported. Findings from this study suggest that colonisation of Ranunculus into the Southern Hemisphere has been a dynamic process and several long distance dispersal events and different colonisation routes have been used. Dispersal from New Zealand to Australia and vice versa, has also been inferred. Bird transportation and oceanic currents are speculated as being the most likely vectors for long dispersal for this group. Morphological variability at the species level is a feature of several species of Ranunculus worldwide. In New Zealand, the alpine species R. insignis and R. enysii are characterised by extensive morphological variability across their distribution range. Currently, these two species include a number of geographically restricted forms that in earlier taxonomic treatments were considered as separate species. Analysis of qualitative and quantitative morphological characters using parametric and non-parametric statistical tests and multivariate analysis, habitat characterisation using environmental variables from the GIS database LENZ and molecular analyses of nrDNA and cpDNA sequences have provided a framework for interpreting and understanding the nature of this phenotypic variation. An argument based on morphological, genetic and ecological support for the reinstatement of the species R. insignis, R. lobulatus and R. monroi is presented here. The last two species may correspond to lineages of recent origin. Hybridisation and introgression between R. insignis and R. lobulatus are suggested as being responsible for intermediate phenotypes found in areas where their distribution overlaps. Morphological variability in R. enysii is inferred to have had a complex origin. The species has a disjunct distribution and events of hybridisation and/or introgression with R. monroi and R. gracilipes seems to have occurred in some of the northern and southern populations, respectively. These hybrid lineages may have swamped out pure lineages of R. enysii and eliminated the ancestral phenotype. Studies including assessment of gene flow using microsatellites, phenotypic stability under common garden condition and pollination experiments will be necessary to further test these hypotheses. Contrary to the latter two species, R. lyallii is morphologically uniform across its distribution range but genetically diverse (11 haplotypes, one of them shared with R. buchananii). Morphological stability in this species is probably explained by morphological stasis and habitat specialisation. The alpine Ranunculus group is outstanding in the New Zealand flora in terms of its great phenotypic and ecological diversity of its members. These two features plus the monophyletic nature of the group and its recent origin have suggested to previous researchers that the radiation of this group has been adaptive. Phylogenetic analysis of 20 taxa in this group using nrDNA and cpDNA sequences has shown that the group includes four lineages and that genetic diversity between the species forming each linage is low. This confirms findings from earlier studies by Lockhart et al. (2001). Cluster Analysis, multidimensional scaling analysis and histological and scanning microscopy observations of morphological and anatomical vegetative and reproductive characters were used to quantify the extent of morphological diversity in the group. Habitat diversity of this group was characterised using 16 environmental variables available from the GIS database LENZ and analysed using Canonical variates analysis. Although four habitat types were identified, there was no correlation between habitat and phenotype as predicted for an adaptive radiation. A number of alternative explanations for this lack of correspondence are discussed. The conclusion drawn from this study was that available data layers and resolution of LENZ limit the use of GIS databases for testing hypotheses of adaptation in the New Zealand Alps.
65

Polyunsaturated fatty acids : evidence for non-substitutable biochemical resources in Daphnia galeata

Wacker, Alexander, Elert, Eric von January 2001 (has links)
The factors that determine the efficiency of energy transfer in aquatic food webs have been investigated for many decades. The plant-animal interface is the most variable and least predictable of all levels in the food web. In order to study determinants of food quality in a large lake and to test the recently proposed central importance of the long-chained eicosapentaenoic acid (EPA) at the pelagic producer-grazer interface, we tested the importance of polyunsaturated fatty acids (PUFAs) at the pelagic producerconsumer interface by correlating sestonic food parameters with somatic growth rates of a clone of Daphnia galeata. Daphnia growth rates were obtained from standardized laboratory experiments spanning one season with Daphnia feeding on natural seston from Lake Constance, a large pre-alpine lake. Somatic growth rates were fitted to sestonic parameters by using a saturation function. A moderate amount of variation was explained when the model included the elemental parameters carbon (r2 = 0.6) and nitrogen (r2 = 0.71). A tighter fit was obtained when sestonic phosphorus was incorporated (r2 = 0.86). The nonlinear regression with EPA was relatively weak (r2 = 0.77), whereas the highest degree of variance was explained by three C18-PUFAs. The best (r2 = 0.95), and only significant, correlation of Daphnia's growth was found with the C18-PUFA α-linolenic acid (α-LA; C18:3n-3). This correlation was weakest in late August when C:P values increased to 300, suggesting that mineral and PUFA-limitation of Daphnia's growth changed seasonally. Sestonic phosphorus and some PUFAs showed not only tight correlations with growth, but also with sestonic α-LA content. We computed Monte Carlo simulations to test whether the observed effects of α-LA on growth could be accounted for by EPA, phosphorus, or one of the two C18-PUFAs, stearidonic acid (C18:4n-3) and linoleic acid (C18:2n-6). With >99 % probability, the correlation of growth with α-LA could not be explained by any of these parameters. In order to test for EPA limitation of Daphnia's growth, in parallel with experiments on pure seston, growth was determined on seston supplemented with chemostat-grown, P-limited Stephanodiscus hantzschii, which is rich in EPA. Although supplementation increased the EPA content 80-800x, no significant changes in the nonlinear regression of the growth rates with α-LA were found, indicating that growth of Daphnia on pure seston was not EPA limited. This indicates that the two fatty acids, EPA and α-LA, were not mutually substitutable biochemical resources and points to different physiological functions of these two PUFAs. These results support the PUFA-limitation hypothesis for sestonic C:P < 300 but are contrary to the hypothesis of a general importance of EPA, since no evidence for EPA limitation was found. It is suggested that the resource ratios of EPA and α-LA rather than the absolute concentrations determine which of the two resources is limiting growth.
66

Nouvelles perspectives pour comprendre la reconnaissance des défauts d'empaquetage lipidique par le senseur de courbure membranaire ALPS (Amphipathic Lipid Packing Sensor)

Gonzalez-Rubio Garrido, Paula 27 November 2009 (has links) (PDF)
Des motifs structuraux largement impliqués dans les processus de modulation de la courbure membranaire sont les hélices amphipathiques. Parmi eux, un senseur de la courbure exhibant des propriétés particulières a été identifiée récemment : ALPS (ArfGAP1 Amphipathic lipid packing sensor). Il a été montré que son interaction avec la membrane était indépendante des charges Žlectrostatiques En effet, le modèle actuel suggère que les résidus hydrophobes soient les responsables de l'ancrage d'ALPS ˆ la membrane en reconaissant les défauts d'empaquetage lipidique. Par simulations par dynamique moléculaire des différentes membranes lipidiques avec le motif ALPS, nous montrons que ce senseur exhibe une considérable liberté conformationnelle et structurelle qui l'habilitent ˆ explorer les défauts d'empaquetage aux niveaux des têtes polaires ainsi qu'au niveau des chaînes aliphatiques. Nous proposons des nouvelles perspectives au niveau atomique de la reconnaissance des défauts d'empaquetage lipidique par ALPS o la déformabilité et flexibilité structurale ainsi que les propriétés dynamiques et physiques de la membrane jouent un r™le prépondérant.
67

Paraglacial Rockslope Stability

McColl, Samuel Thomas January 2012 (has links)
The aim of this research was to study the relationship between rock slope stability and glacial processes. An in-depth analysis of our current understanding of how glaciated rock slopes develop instability and movement during deglaciation is presented; this shows that understanding is incomplete without an appreciation of the variable mechanical behaviour of glacier ice. In this thesis, I argue that: (1) The ductile behaviour of ice at low strain rates allows movement of rock slopes buttressed by ice. Field evidence and simple force models are used to explore rate of movement of ice-contact slopes and the conditions under which they evolve. The results indicate that large rockslides can move and deform glacial ice at rates of 10-2 to 102 m-yr. This implies that ice-contact slope movement may be important for slope evolution and the erosion and entrainment processes of glaciers; and (2) the elastic strength of glacier ice at the high strain rates associated with seismic shaking enables ice to modify the response of the surrounding rock to seismic shaking. To explore this, numerical analyses of the interaction between glacial erosion, glacier mass, topography, and earthquake shaking intensity are undertaken. Shaking of mountains of variable shape and with different levels of ice inundation is simulated using FLAC 6.0. The results suggest that complete inundation by ice can significantly reduce shaking intensity. This, in combination with glacial steepening of slopes, may make recently deglaciated slopes more prone to coseismic failure. In the final chapter of the thesis, I present a conceptual model of the evolution of slope stability during stages of glaciation and deglaciation. The model incorporates the ideas presented in the thesis. I then offer recommendations for how our understanding of these processes can be further advanced.
68

Neotectonics and Paleoseismology of the Central Alpine Fault, New Zealand

De Pascale, Gregory Paul January 2014 (has links)
The Alpine Fault is a major plate boundary structure, which accommodates up to 50-80% of the total plate boundary motion across the South Island of New Zealand. The fault has not ruptured historically although limited off-fault shaking records and on-fault dating suggest large to great (~ Mw 8) earthquakes (every ~100-480 years; most recently in 1717), making it potentially one of the largest onshore sources of seismic hazard in New Zealand. The central section of the Alpine Fault, which bounds the highest elevations in the Southern Alps, is one of the most poorly characterised sections along the fault. On-fault earthquake timing in addition to the amount of dextral slip during major earthquakes was unknown along a 200-km-long section of the central Alpine Fault, while the amount of co-seismic hanging wall uplift was poorly known, prior to the present work. In this thesis I address these knowledge gaps through a combination of light detection and ranging (lidar), field, and stratigraphic mapping along with sample dating to constrain earthquake timing, style of faulting, and hanging wall rock uplift rates. Using lidar data coupled with field mapping I delineated the main trace of the Alpine Fault at Gaunt Creek as a north-striking fault scarp that was excavated and logged; this is part of a 2-km-wide restraining bend dominated by low-angle thrust faulting and without the clear strike-slip displacements that are present nearby (<5 km distant along strike in both directions). Where exposed in this scarp, the fault-zone is characterized by a distinct 5-50 cm thick clay fault-gouge layer juxtaposing hanging wall bedrock (mylonites and cataclasites) over unconsolidated late-Holocene footwall colluvium. An unfaulted peat at the base of the scarp is buried by post-most recent event (MRE) alluvium and yields a radiocarbon age of A.D. 1710–1930, consistent with sparse on-fault data, validating earlier off-fault records that suggest a 1717 MRE with a moment magnitude of Mw 8.1 ± 0.1, based on the 380-km-long surface rupture. Lidar and field mapping also enabled the identification and measurement of short (<30 m), previously unrecognized dextral offsets along the central section of the Alpine Fault. Single-event displacements of 7.5 ± 1 m for the 1717 earthquake and cumulative displacements of 12.9 ± 2 m and 22 ± 2.7 m for earlier ruptures can be binned into 7.1 ± 2.1 m increments of repeated dextral (uniform) slip along the central Alpine Fault. A comparison of these offsets with the local paleoseismic record and known plate kinematics suggests that the central Alpine Fault earthquakes in the past 1.1 ka may have: (i) bimodal character, with major surface ruptures (!Mw 7.9) every 270 ± 70 years (e.g. the 1717 event) and with moderate to large earthquakes (!Mw 7) occurring between these ruptures (e.g. the 1600 event); or (ii) that some shaking data may record earthquakes on other faults. If (i) is true, the uniform slip model (USM) perhaps best represents central Alpine Fault earthquake recurrence, and argues against the applicability of the characteristic earthquake model (CEM) there. Alternatively, if (ii) is true, perhaps the fault is “characteristic” and some shaking records proximal to plate boundary faults do not necessarily reflect plate-boundary surface ruptures. Paleoseismic and slip data suggest that (i) is the most plausible interpretation, which has implications for the understanding of major plate-boundary faults worldwide. Field mapping, geological characterisation, geophysical mapping, and optically stimulated luminescence (OSL) dating of on-fault hanging wall sediments were used to better constrain the geometry and kinematics of Holocene deformation along the rangefront of the Southern Alps at the Alpine Fault near the Whataroa River. The fault here is dextral-reverse, although primarily strike-slip with clear fault traces cutting across older surfaces of varying elevations. Deformational bulges are observed along these traces that are likely thrust-bounded. A terrace of Whataroa River sediments was found on the hanging wall of the Alpine Fault approximately ~ 55-75 m (when considering uncertainties) above the floodplain of the Whataroa River. OSL ages for a hanging wall sediments of 10.9 ± 1.0 ka for the aforementioned terrace, 2.8 ± 0.3 ka for Whataroa River terrace deposits in a deformational bulge, and 11.1 ± 1.2 ka for a rangefront derived fan indicate Holocene aggradation along the rangefront and hanging wall uplift rates of 6.0 ± 1.1 mm/yr. The sub-horizontal, laterally continuous, and planar-bedded Whataroa-sourced terrace deposits suggest that the adjacent bounding faults are steeply-dipping faults without geometries in the shallow subsurface that would tend to cause sedimentary bed rotation and tilting. Using data from the approximately 100-m deep pilot DFDP boreholes together with lidar and field mapping, I present a review of the Quaternary geology, geomorphology, and structure of the fault at Gaunt Creek, and estimate new minimum Late-Pleistocene hanging wall rock uplift rates of 5.7 ± 1.0 mm/yr to 6.3 ± 1.1 mm/yr (without considering local erosion) that suggest that the Southern Alps are in a dynamic steady state here. GPS-derived “interseismic” vertical uplift rates are < 1 mm/yr at the Alpine Fault, so the majority of rock uplift at the rangefront happens during episodic major earthquakes, confirming with on-fault data that slip occurs coseismically. Notably the uplift rates from both Mint and Gaunt Creek are consistent between the two sites although the primary style of faulting at the surface is different between the two sites, suggesting consistent coseisimc uplift of the Southern Alps rangefront along the Alpine Fault in major earthquakes. This thesis collected new on-fault datasets that confirm earlier inferences of plate-boundary fault behaviour. This study of the high-uplift central section of the Alpine Fault provides the first on-fault evidence for the MRE (i.e. 1717) and repeated of dextral slip during the MRE and previous events as well as new hanging wall uplift data which suggests that the majority of rangefront uplift occurs in earthquakes along the Alpine Fault. Because the fault has not ruptured for ~300 years, it poses a significant seismic hazard to southern New Zealand.
69

Late Pleistocene Glacial Geology of the Hope-Waiau Valley System in North Canterbury, New Zealand

Rother, Henrik January 2006 (has links)
This thesis presents stratigraphic, sedimentological and geochronological results from valley fill and glacial moraines of the Hope-Waiau Valleys in North Canterbury, New Zealand. The findings demonstrate that a substantial portion of the modern valley fill comprises in-situ sedimentary sequences that were deposited during the penultimate glaciation (OIS 6), the last interglacial (OIS 5) and during the mid-late last glacial cycle (OIS 3/2). The sediments survived at low elevations in the valley floor despite overriding by later glacial advances. Sedimentologically, the fill indicates deposition in an ice marginal zone and consists of paraglacial/distal-proglacial aggradation gravels and ice-proximal/marginal-subglacial sediments. Deposition during glacial advance phases was characterized by the sedimentation of outwash gravels and small push moraines while glacial retreat phases are dominated by glaciolacustrine deposits which are frequently interbedded with debris flow diamictons. The overall depositional arrangement indicates that glacial retreat from the lower valley portion occurred via large scale ice stagnation. Results from infra-red stimulated luminescence (IRSL) dating gives evidence for five large aggradation and degradation phases in the Hope-Waiau Valleys over the last 200 ka. Combined with surface exposure dating (SED) of moraines the geochronological results indicate that glacial advances during OIS 6 were substantially larger in both ice extent and ice volume than during OIS 4-2. The last glacial maximum (LGM) ice advance occurred prior to 20.5 ka and glacial retreat from extended ice positions began by ~18 ka BP. A late glacial re-advance (Lewis Pass advance) occurred at ~13 ka BP and is probably associated with a regional cooling event correlated to the Antarctic Cold Reversal (ACR). The findings from the Hope-Waiau Valleys were integrated into a model for glaciations in the Southern Alps which uses data from a snow mass balance model to analyse the sensitivity of glacial accumulation to temperature forcing. Model results indicate that in the central hyperhumid sector of the Southern Alps ice would expand rapidly with minor cooling (2-4℃) suggesting that full glaciation could be generated with little thermal forcing. Some Quaternary glacial advances in the Southern Alps may have been triggered by regional climate phenomena (e.g. changes in ENSO mode) rather than requiring a thermal trigger from the Northern Hemisphere.
70

On the links between natural amenities, residential processes and urban planning : lessons from an Alpine urban region / Sur les liens entre les aménités naturelles, le développement résidentiel et la planification urbaine : enseignements d'une région urbaine alpine

Cremer-Schulte, Dominik Clemens 15 June 2016 (has links)
Les régions urbaines alpines et en proximité des Alpes présentent des caractéristiques spécifiques: elles combinent une ressource foncière limitée pour l'urbanisation et une qualité environnementale particulière dans l'arrière-pays. Cette combinaison les rend particulièrement propices à la péri-urbanisation, et potentiellement à la ségrégation sociale. Dans le contexte d'une métropolisation croissante, ces deux processus entravent des objectifs centraux de la planification urbaine, à savoir la compacité des formes urbaines, la mixité fonctionnelle, l'égalité territoriale et la cohésion sociale. Dans les régions urbaines alpines, les liens entre l'environnement montagnard, les politiques de planification et les processus résidentiels à l’œuvre restent toutefois peu connus.Cette thèse analyse la planification urbaine et des choix de localisation résidentielle en région urbaine alpine. Elle cherche à comprendre les liens entre l'environnement montagnard, les politiques de planification urbaine et deux processus résidentiels: la péri-urbanisation et la ségrégation sociale. Son objectif général est de mettre en lumière comment et dans quelle mesure ces processus résidentiels sont influencés par (i) l'environnement montagnard et (ii) les politiques de planification pour ainsi fournir des recommandations pour la planification territoriale en région urbaine. Pour cela, nous nous appuyons sur trois contributions distinctes en utilisant la région urbaine de Grenoble comme zone d'étude centrale.La première contribution porte sur les changements dans la pratique de la planification urbaine contemporaine dans la région d'étude. Basée sur une recherche qualitative, elle se concentre sur l'émergence d'une planification territoriale stratégique et sa montée en échelle vers des périmètres de planification plus larges intégrants les espaces péri-urbains. Le chapitre montre la création de nouvelles arènes de gouvernance qui remettent en question les cultures de planification locale.La deuxième contribution analyse les liens entre les préférences pour l'environnement naturel, les choix de localisation résidentielle et la ségrégation sociale. En utilisant des modèles de choix de localisation pour la région d'étude et la région métropolitaine de Marseille, cette partie présente une analyse de ségrégation contrefactuelle qui compare les résultats de ségrégation og avec fg{} et og sans fg{} les préférences pour l'environnement naturel entre les deux régions. Le principal résultat est que la recherche des milieux naturels par les ménages a des effets significatifs sur la ségrégation sociale. Cette recherche a le plus souvent tendance à renforcer la ségrégation, mais peut également être un facteur d'atténuation.La dernière contribution étudie les liens entre les politiques de planification urbaine et les processus résidentiels. Le chapitre développe un modèle de choix discrets pour créer et analyser des simulations de demande résidentielle pour différents scénarios de politique de planification. Les résultats illustrent que les scénarios tendanciels de planification soutiennent et potentiellement renforcent la périurbanisation dans la région d'étude. Des politiques de planification plus contraignantes semblent capables de freiner et potentiellement d'inverser la dispersion de la demande. Les politiques visant à ré-centraliser la demande tendent à maintenir, voire accroître les niveaux de ségrégation sociale.Les résultats de cette thèse suggèrent l'importance d'une prise en compte plus grande de l'environnement naturel dans la planification urbaine et territoriale. Si les disparités spatiales dans la qualité environnementale contribuent aux processus résidentiels qui portent atteintes aux objectifs du développement urbain, les politiques de planification devraient rendre compte de ces disparités afin de limiter l'étalement urbain, la ségrégation sociale et l'inégalité environnementale, non seulement dans un contexte de région urbaine alpine. / Urban regions in and close to the Alps have specific characteristics: they combine a limited land resource for urban development with particular environmental quality in their mountainous hinterland. This combination makes them particularly prone to peri-urbanisation, and potentially social segregation. In the context of continued metropolisation, both of these processes work against central objectives of urban planning, notably compactness of settlement patterns, functional mix, social equity and cohesion. In Alpine urban regions, the links between the mountain environment, urban planning policies and residential processes remain, however, not well understood.This thesis analyses urban planning and residential moves in an Alpine urban region. It seeks to understand the links between the mountain environment, urban planning and notably two residential processes: peri-urbanisation and social segregation. Its general objective is to investigate how and to what extent these residential processes are influenced by (i) the mountain environment and (ii) urban planning policies and to develop recommendations for urban and regional planning. The thesis does this via three distinct contributions which use the urban region of Grenoble in the French Alps as a central study area.The first contribution addresses changes in contemporary urban planning practice in the study region. Based on qualitative research, it focuses on the shift towards strategic spatial planning and on territorial re-scaling towards large urban-peri-urban planning perimeters. The chapter shows the creation of new governance arenas which call into question local planning cultures.The second contribution investigates the links between preferences for the natural environment, residential moves and social segregation. Using location choice models for the study region and the Marseille metropolitan area, this chapter presents a counterfactual segregation analysis that compares segregation outcomes ``with'' and ``without'' preferences for the natural environment. The main result is that households' search for natural environments has significant impacts on social segregation. It most often contributes to reinforcing segregation, but can also be an attenuating factor.The last contribution investigates the links between urban planning policies and residential processes. The chapter develops a residential location choice model in order to predict and analyse residential demand patterns for different planning policy scenarios in terms of concentration and segregation. The scenario results show that continued trends in urban planning policies would sustain and potentially reinforce peri-urbanisation in the region. Confining planning policies are found to be capable of curbing and potentially reversing demand dispersion. Policies that aim at re-centralising demand sustain and potentially increase social segregation levels.The results of this thesis call for a stronger integration of the natural environment in urban and regional planning. If spatial disparities in environmental qualities contribute to residential processes that are detrimental to compact urban forms and an equitable access to environmental quality, then planning should incorporate and account for these disparities in order to prevent further loss of land resources, socio-spatial fragmentation and environmental inequality, not only in an Alpine urban region context.

Page generated in 0.0408 seconds