Teses / dissertações sobre o tema "Geographic shift"

Les changements mondiaux modernes, tels que le changement climatique et la sixième extinction de masse, perturbent profondément nos sociétés et nos écosystèmes. Les nouvelles technologies, notamment l'apprentissage machine, sont à la fois facteurs aggravants et moyens potentiels d'atténuation des défis que posent ces changements. En 2015, les Nations Unies ont établi les Objectifs de Développement Durable pour évaluer l'impact écologique et les risques pour les populations, révélant que les pays du Sud sont les plus éloignés des objectifs de ce cadre. Les pays avec des infrastructures numériques limitées déploient moins les modèles d'apprentissage machine, rencontrant un problème de glissement de contexte dû à l'incohérence entre les données d'entraînement et de déploiement. En vision par ordinateur, ce glissement est exacerbé par l'absence de données des pays du Sud dans les ensembles d'entraînement, conduisant à une performance réduite des modèles dans ces contextes. Dans cette thèse, nous faisons le pont entre l'intelligence artificielle au service de la science soutenable et l'inclusivité des systèmes de vision par ordinateur. Nous montrons comment les approches qui ont précédé à la notre pour démontrer le manque d'inclusivité des systèmes de vision actuels ont fait l'impasse sur des points importants de la problématique, comme la formalisation du biais géographique et des métriques qui témoignent de son impact. Cela nous amène à proposer un protocole pour la formalisation des biais, qui se base sur l'identification d'une source, d'un type et d'un impact pour la caractérisation de ce dernier. Ce protocole est implémenté pour le biais géographique, en premier lieu sur des données synthétiques. Les bases de données synthétiques connues ne possédant pas de biais géographique, nous nous inspirons des modifications de la base de données MNIST pour créer des bases de données synthétiques comportant des biais géographiques. Nous utilisons ces derniers pour tester l'implémentation de notre protocole et démontrer son utilité. Nous expérimentons ensuite le protocole sur des données réelles pour la caractérisation du biais occidental dans les systèmes de vision, et constatons que les résultats obtenus sont différents de ceux attendus, allant à l'encontre des observations dans les précédents travaux académiques. Nous procédons à une analyse visuelle à différents niveaux de granularité de ces résultats pour tenter de les comprendre et proposer des théories les expliquant. Au final, nous mettons en avant la présence de biais concomitants, des éléments composant le biais géographique mais ayant des impacts différenciés avec l'entité principale. Ces biais concomitants empêchent la caractérisation du biais géographique en influençant les prédictions des modèles. Nous montrons donc comment la problématique de la caractérisation du biais géographique se révèle plus complexe qu'elle ne peut le paraître au premier abord, quels sont les écueils actuels et quelles pistes sont privilégiées pour remédier aux problèmes rencontrés. Globalement, nous proposons à la communauté scientifique des outils pour mieux appréhender les problématiques de déploiement de modèles dans les pays du Sud, afin de mieux comprendre les enjeux de ces déploiements pour des applications en science soutenable
Modern global changes, such as climate change and the sixth mass extinction, are profoundly disrupting our societies and ecosystems. New technologies, including machine learning, are both aggravating factors and potential means of mitigating the challenges posed by these changes. In 2015, the United Nations established the Sustainable Development Goals to assess the ecological impact and the risks for populations, revealing that the countries of the South are the furthest from achieving the objectives of this framework. Countries with limited digital infrastructures deploy less machine learning models, encountering a problem of context shift due to inconsistency between training and deployment data. In computer vision, this shift is exacerbated by the absence of data from southern countries in the training sets, leading to reduced model performance.In this thesis, we bridge the gap between artificial intelligence for sustainable science and the inclusivity of computer vision systems. We show how previous approaches to demonstrating the lack of inclusivity of current vision systems have overlooked important aspects of the problem, such as the formalisation of geographical bias and the metrics that reflect its impact. This has led us to propose a protocol for formalising bias, based on the identification of a source, a type and an impact in order to characterise it. This protocol has been implemented for geographical bias, initially on synthetic data. As known synthetic databases do not have a geographical bias, we create synthetic datasets with geographical biases, inspired by previous synthetic modifications of the MNIST database. We use these to test the implementation of our protocol and demonstrate its usefulness. We then experiment with the protocol on real data for characterising western bias in vision systems, and find that the results obtained are different from those expected, going against observations in previous academic work. We carry out a visual analysis of these results at different levels of granularity in an attempt to understand them and to propose possible themes for future research. In the end, we highlight the presence of concomitant biases, elements that make up the geographical bias but have different impacts that the main entity. These concomitant biases prevent the characterisation of the geographical bias by influencing the predictions of the models.We therefore show how the problem of characterising geographical bias is more complex than it might at first appear, what the current pitfalls are and what avenues are being pursued to remedy the problems encountered. Overall, we offer the scientific community tools to better understand the problems of deploying models in developing countries, in order to better understand the challenges of these deployments for applications in sustainable science

Thesis (S.M.)--Massachusetts Institute of Technology, Dept. of Political Science, 2010.
Cataloged from PDF version of thesis.
Includes bibliographical references (p. 73-74).
The 20th century witnessed the steady decline of the ability of states, particularly great powers, to defeat insurgencies. During the same period, the world has become both more populous and more urban. As people have taken to the cities, so too have insurgents increasingly made battlefields out of urban areas. This study has sought to determine the impact of urbanization on insurgency outcomes using a post-war dataset of insurgencies. It has predicted that urbanized insurgencies favor the insurgent by facilitating concealment and cover, nullifying the relatively power differential enjoyed by states, and providing them with an abundance of soft targets useful for undermining the counterinsurgent's legitimacy. Although constrained by a number of data limitations, the results demonstrated that more urbanized insurgencies were a significant challenge to counter insurgents. By partitioning the dataset by insurgency type, the study was able to determine unique predictors of conflict outcome for each type. Urbanized insurgencies are particularly hard to defeat when the counterinsurgent is a foreign occupier, more democratic, and the insurgency has external support. Rural insurgencies become more difficult to defeat the more linguistically diverse the population. Furthermore, by increasing the number of conflict casualties, rural insurgents can particularly benefit from rough terrain.
by Nicholas T. Calluzzo.
S.M.

Our world is changing rapidly and factors like urbanisation, changed agricultural practices and climate change are causing losses in butterfly diversity. It is therefore of importance to understand the source of their diversity. Given the remarkable diversity of herbivorous insects compared to their non-herbivorous sister groups, changes in host use have been implicated as a promoter of speciation. This thesis looks at geographical aspects of host range evolution and the plasticity of host use. We show that butterflies in the subfamily Nymphalinae that feed on a wide range of host plants have larger geographic ranges than species with narrower host ranges. Although tropical butterflies appear to be more specialised than temperate species, this effect is lost when controlling for the differences in geographic range. Geographic variation in host plant use within Polygonia faunus, related to morphologically distinct subspecies, did not show any genetic differentiation. This suggests that the observed variation in host plant use is a plastic response to environmental differences. Reconstructing host use for the Polygonia-Nymphalis and Vanessa group shows that plasticity is also important for understanding host use at the level of butterfly genera. Using unequal transition costs and including larval feeding ability revealed that frequent colonisations of the same plant genus can often be explained by non-independent processes, such as multiple partial losses of host use, recolonisation of ancestral hosts, and parallel colonisations following a preadaptation for host use. These processes are further reflected in the conservative use of host plant orders within the butterfly family Nymphalidae. Few taxa feed on more than one host plant order, and these expansions occur at the very tips of the tree, which we argue is evidence of the transient nature of generalist host use. These insights improve our understanding of how host range evolution may promote diversification.
At the time of the doctoral defence,the following papers were unpublished and had a status as follows: Paper 3: Submitted; Papers 4 and 5: Manuscripts

Industries and regional economies evolve as a result of the interplay between local and non-local factors. Increasing globalization of both production- and innovation activities implies a shift in the relevant scales of interaction from the local towards the global level. This paper is concerned with the implications of such scale shifts for the role of the region and for cluster-related regional policies. It examines what is left of the role of regional settings in fostering economic development when extra-regional drivers of change increase in importance. We investigate this crucial question with two in-depth case studies of the medical technologies sector, in which such scale shifts have been particularly pronounced. Our findings from empirical material collected in Scania/Sweden and Vienna/Austria illustrate the ways in which changes in national and supra-national regulatory frameworks have had a profound impact on the innovation activities of individual firms and the way to develop and launch new products, and subsequently on the regions in which they cluster. Such scale-shifts have on the one hand limited the potential for regional policy to shape the cluster's path through support for supply-side factors. Yet some critical assets remain local but are increasingly difficult to access. By addressing such barriers to access, regional policy can still strongly affect the opportunities for innovation. Furthermore, in an increasingly open industry system, we see an expanded role for regional policy in supporting firms to access critical assets and sources of innovation found external to the region.

The city of Moab, an outdoor recreation hub in eastern Utah, has been encountering both shifts in the seasonality of visitation, and increases in tourist visitation, even with summer temperatures above the normal high. Tourism research describing the effects of climate change on the outdoor recreation industry has focused on winter, snow-dependent activities, while studies in Moab city have focused on the economic value of outdoor recreational activities. Few studies have described the relationship between seasonal tourism and climate change for arid desert locations. The purpose of this study is to describe how the tourism and recreation industry in Moab, Utah is experiencing and adapting to changes in climate. The first part of the research is a regression analysis of existing data, exploring the correlation between monthly national park visitation and climate factors (long-term monthly average temperature and temperature anomaly) that influence tourism seasonality in Arches National Park and Canyonlands National Park. Using an online survey, the second part of the research identifies how seasonality shifts are perceived by different actors in Moab and how they are responding to manifestations of climate change. Regression results indicate that as temperature increases in the region around Moab, national park visitation also increases. Moab businesses are not directly adapting to climate change, but are adapting to perceived increases in visitation throughout the year. The majority of Moab businesses do not attribute the increase in visitation to climate variables, instead visitation increases are believed to be a result of the popularity of the town and the region.

This thesis explores the impact of the city of Stockholm􏰀s 2015 Green Parking Rates guideline on transportation mode shift. The guidelines were established in hopes of nudging occupants of newly built residential developments towards a mode shift and in so doing, towards car-light, car- free and more sustainable living. This nudging is facilitated through the utilization of positive mobility services such as the offering of bike-share and car-share services to residents, in hopes of reducing their need and desire for private automobiles. As a result of incorporating positive mobility services, the development community receives a reduction on the parking spaces they are obligated to construct, which come at a high economic cost to the individual property developers, those purchasing or renting their units as well as society as a whole. Consequently, the guidelines are a meant to be a tool to help the city of Stockholm reduce congestion and meet their newest sustainability goals. This thesis explores the perspectives of the development community as well as the planning departments at the city of Stockholm through the conducting of a policy analysis as well as through 16 semi structured interviews and explores some of the successes and challenges in establishing a mode shift. However, due to the short time period since the establishment of the guidelines, the city of Stockholm nor the development community have conducted a comprehensive evaluation to assess the guidelines􏰀 utility in facilitating a mode shift. The thesis suggests that a more collaborative process pre, during and after the development of projects would better serve Stockholm and its development community in achieving its sustainability goals.

[Truncated abstract] Aspects of the biology of the commercial sea cucumber Holothuria whitmaei were investigated at Coral Bay, Ningaloo Reef, Western Australia. The study was partitioned into several components: i) spatial distribution, ii) temporal changes in behaviour and iii) reproduction biology. The spatial distribution of H. whitmaei at Coral Bay was typical of that reported in the literature. H. whitmaei had distinct preferences for outer reef habitats, including the outer reef flat and reef slope. However, the distribution of H. whitmaei within these habitats was heterogeneous, or, aggregated within certain micro-habitat zones - predominantly at the leading edge of the reef flat, perpendicular to the prevailing current. Two potential biological advantages of this distribution were hypothesised: i), that species aggregation enhances prospects for gamete fertilisation, a process which may be impeded under typical densities, and ii), large deposits of detrital matter, an important food source for holothurians, may accumulate within these zones. ... A striking feature of the reproduction biology of this species was the potential for specimens to mature asynchronously. It was hypothesised that this phenomenon may be a reflection of isolated individuals located too far from conspecifics to receive pheromone signals; cues which are known to entrain synchronous gonad development in some holothurians. Hence, it was proposed that aggregations of H. whitmaei may be important to the maintenance of population recruitment, given that animals at the periphery of species concentrations may have relatively little chance of achieving fertilisation. ... Given that H. whitmaei were observed to maintain highly specific patterns of distribution, this may have significant ramifications for trophic level cascades in the outer reef zone, particularly where this species is present in higher densities (i.e. >100 ind. ha-1). The findings of this study, apart from highlighting the spatial and temporal biological attributes which may facilitate feeding and reproductive success, also emphasised the importance of biological knowledge to the management of sea cucumber fisheries. The study highlighted the need for further research to ascertain both the importance of species aggregations to population recruitment, and of the actual densities required to achieve high rates of gamete fertilisation. Such knowledge may help ultimately to identify suitable habitats for inclusion in marine protected areas.

Les technologies du numérique modifient profondément la manière dont les sociétés appréhendent et se représentent leur espace. La cartographie n’est pas à l’écart de ces changements et les cartes sont de plus en plus nombreuses et sont utilisées sous de nouvelles formes. C’est en particulier le cas de la consultation d’itinéraires uniques, rendue plus aisée par les évolutions techniques et technologiques. L’usage de ces itinéraires est aujourd’hui l’une des principales fonctionnalités des cartes numériques, dont un grand nombre sont issues de sociétés implantées aux États-Unis.Comment appréhender, dans le cadre d’une analyse diachronique et comparatiste, le rôle des cartes d’itinéraire dans la cartographie numérique? S’agit-il d’une nouveauté ou de la réactualisation d’une forme cartographique plus ancienne ? Quelle place tient ce type de représentations dans une perspective croisée?La thèse propose de répondre à ces questions par une analyse large à trois entrées : cartobibliographique, sémiologique et processuelle, en se basant sur des corpus de cartes issus de la Bibliothèque nationale de France et de laNewberry Library. Les principaux résultats de ce travail apportent un éclairage sur les changements en cours avec le passage d’une cartographie majoritairement papier à une cartographie majoritairement écran. Ils invitent finalement à penser ces changements à travers une redéfinition du statut de la carte à l’ère numérique
Digital technologies deeply change the way in which societies grasp their environment and represent space Cartography is not exempt from these changes, maps are more widespread than ever and are being used for new purposes. Among them, the use of route specific maps, made easier by technical and technological developments. Many online maps are used for itineraries, and most of them come from United States-based corporations.These observations raise the questions of how to understand this specific use of maps when put in a chronological and comparative perspective ? Is this an innovation or rather an actualization of a previous type of mapping practice ? What is the status of these itineraries when studied in a multifaceted perspective ?This research addresses these questions using three main approches : cartobibliographical, semiological and processual, and relying on extensive map collections from the Bibliothèque nationale de France and the Newberry Library. The main results bring new insights on the changes taking place with the transition from a primarily paper cartography to a primarily on-screen cartography and call for a redefinition of the status of maps in the digital era

Prédire les réponses de la biodiversité aux changements climatiques anthropiques est devenu un champ de recherche avec des enjeux scientifiques et sociétaux majeurs. Mon travail de thèse a consisté à évaluer les impacts du réchauffement climatique sur un parasitoïde de drosophiles, Leptopilina boulardi, à une petite échelle géographique, le sud-est de la France. L'objectif était non seulement d'examiner l'évolution de la distribution du parasitoïde en réponse à une hausse des températures qu'il fallait préciser à cette échelle géographique, mais aussi d'appréhender les adaptations mises en place dans la zone de progression de l'espèce. Dans un premier temps, l'analyse de données d'échantillonnages et de données météorologiques m'ont permis de mettre en évidence une rapide expansion de l'aire de répartition du parasitoïde vers le nord, à un taux moyen de 90km/décennie, simultanément à une augmentation moyenne de la température de 1,57°C ces 30 dernières années, dans l'aire d'étude. Après avoir identifié les principaux facteurs environnementaux, structurant la répartition spatiale de L. boulardi, j'ai modélisé sa distribution potentielle dans le sud-est de la France, sous conditions climatiques actuelles et pour 2050, pour deux scénarios d'émission de CO2. En 2050, la distribution géographique de L. boulardi devrait considérablement s'étendre vers le nord sous l'effet des changements climatiques. Ensuite, en mesurant plusieurs traits d'histoire de vie selon 4 régimes thermiques fluctuants, j'ai montré que les populations de L. boulardi situées en limite d'aire de répartition sont génétiquement différenciées de celles situées dans l'aire centrale de répartition. Le fait que les populations marginales aient une valeur sélective plus importante à faible température suggère une adaptation locale des parasitoïdes dans la zone de progression de l'aire de répartition. La dernière partie de ce travail de thèse a pour objectif de mieux comprendre le processus de colonisation de L. boulardi. Pour cela, j'ai entrepris le développement de marqueurs RAD-sequencing sur 15 populations de cette espèce, distribuées le long d'un cline de latitude dans le sud-est de la France. Les nombreuses données issues du séquençage Illumina me permettront de connaître la structuration génétique de ces populations. L'ensemble de ces résultats obtenus au cours de ma thèse révèlent la force avec laquelle les changements climatiques peuvent impacter les espèces, principalement celles de haut niveau trophique, en provoquant des changements très rapide de distribution et des modifications génotypiques et phénotypiques permettant une meilleure adaptation locale
Predicting biodiversity responses to anthropogenic climate change has become a field of research with major scientific and societal issues. The main goal of my thesis was to evaluate the impacts of global warming on a Drosophila parasitoid, Leptopilina boulardi, at a small geographical scale, the South-East of France. The aim was not only to examine the change in the distribution of the parasitoid in response to rising temperatures, but also to understand the adaptations associated with this change. First, the analysis of insect sampling and meteorological data allowed me to demonstrate a rapid expansion of the parasitoid range to the north with an average rate of 90km/decade as well as a simultaneous temperature increase of 1.57°C on average over the past 30 years in the studied area. Following the identification of the main environmental factors structuring the spatial distribution of L. boulardi, I fitted a model predicting its potential distribution in the south-east of France, under the current climate and in 2050, for two CO2 emission scenarios. In 2050, the geographical distribution of L. boulardi should significantly extend northward as a result of climate change. Then, by measuring several life history traits under four fluctuating temperature regimes, I have shown that populations of L. boulardi located on the border of the range are genetically differentiated from those in the central range. The fact that marginal populations have a greater fitness at low temperature suggests local adaptation of parasitoids in the area of progression of range. The last part of this thesis aimed to better understand the process of colonization of L. boulardi. For this, I undertook the development of RAD-sequencing markers to genotype 15 populations of this species distributed along a cline of latitude in the southeast of France. Numerous data from Illumina sequencing will allow me to characterize the genetic structure of the populations. All the results obtained in my thesis highlight the force with which climate change may impact species, in particular those of high trophic level, causing rapid changes in distribution along with genotypic and phenotypic changes underlying local adaptation

Thesis (Ph.D.)--Cleveland State University, 2009.
Abstract. Title from PDF t.p. (viewed on Jan. 27, 2010). Includes bibliographical references (p. 185-203). Available online via the OhioLINK ETD Center and also available in print.

Elektrifizierte Lastenfahrräder werden als ein Lösungsansatz für die wachsenden Herausforderungen des städtischen Wirtschaftsverkehrs gesehen. Fokus dieser Arbeit ist eine Abschätzung des Einsatzpotenzials dieses Fahrzeugkonzepts unter Betrachtung von konzeptionellen, verkehrlichen und wirtschaftlichen Aspekten. Als kumulative Dissertation enthält sie fünf Fachartikel, gruppiert zu drei Forschungsbeiträgen. Im ersten Forschungsbeitrag wird erörtert, wie erfolgversprechend das E-Lastenrad, eine Neuauflage des alten Konzepts Lastenfahrrad, in einem Markt mit ersten Anwendern (Kurierdienstleistung) ist. Die Auftragsstruktur im Stadtkuriergeschäft bietet ein substanzielles Marktpotenzial für E-Lastenräder, allerdings erschwert die Positionierung zwischen zwei etablierten Modi (Pkw und Fahrrad) den Markteintritt. Der zweite Teil der Analyse weitet den Blick auf alle Branchen und bietet eine strukturierte Beschreibung der verschiedenartigen Einflussfaktoren (Treiber und Hemmnisse), die auf die Lastenradnutzung im städtischen Wirtschaftsverkehr wirken. Als relevante Entscheidungskriterien konnten identifiziert werden: fahrzeugseitige Aspekte, Strukturen und Prozesse des adoptierenden Unternehmens, Einstellungen der Entscheider*innen, weiche Faktoren sowie regulative und räumliche Rahmenbedingungen. Der dritte Beitrag thematisiert die operative Eignung des E-Lastenrads, indem seine Fahrtzeiten einem Pkw gegenübergestellt werden. Bei Strecken bis zu 3 km sind beide Modi nahezu gleich schnell. Die Hälfte aller Fahrten bis 20 km Distanz würde bei einem Wechsel vom Pkw zum Lastenrad höchstens 2–10 min länger dauern (ohne Berücksichtigung der Parksuchzeit). Bereits kleine Änderungen an den Verkehrsbedingungen könnten noch bestehende Vorteile des Pkw spürbar verringern. Insgesamt erweitert die Arbeit maßgeblich das Wissen zu einem „neuen alten“ Fahrzeugkonzept, dem ein Potenzial zur Auflösung von bislang auf das Automobil hin ausgerichteten Systemen beigemessen wird.
Shifting trips to electric cargo bikes is one possible solution to deal with the growing challenges of urban commercial transport. This thesis combines conceptual, transport-related, and economic aspects as a foundation to assess the feasibility of this vehicle concept for freight and service trips. It contains five scientific papers, which provide three research contributions. The first contribution identifies the potentials of electric cargo bikes among first users (i.e., courier logistics services). Electric cargo bikes are an updated and re-envisioned version of freight bicycles. The features of point-to-point courier logistics assignments offer a substantial market opportunity for electric cargo bikes. However, being positioned between two established modes (i.e., car and bicycle) handicaps the market entry of cargo bikes. For the second contribution, the scope was widened to include all business sectors. A structured description is presented of the various determinants (i.e., drivers and barriers) affecting commercial cargo bike use. Among these were vehicle-specific factors, structures and practices of the company, attitudes of decision-makers, soft factors, regulatory frameworks, and spatial conditions. The third contribution explores the travel time differences between electric cargo bikes and cars for commercial trips. For trip distances of up to 3 kilometers, the travel times of both modes largely overlap. Half of all trips up to 20 kilometers would take only a maximum of 2 to 10 minutes longer by electric cargo bike (excluding the additional time for finding a parking spot). Small modifications in traffic could have considerable effects in reducing the current travel time advantages of cars. Consequently, this dissertation contributes towards the state-of-research by expanding the scientific knowledge of a type of vehicle that has the potential to disrupt car-dependent transportation systems.

This computational study reveals the primacy of language contact in the variation of language (Sarah Grey Thomason 2003). The visualization and further analysis confirm the reconceptualization of Chinese linguistic history with the theory of Horizontal Transmission (Shen 2016). Horizontal Transmission situates the development of Mandarin and other Chinese dialects in a sociopolitical landscape as a cultural complex and introduces imperfect learning to the time-capsulated process of Language Shift as an inevitable social phenomenon. The nature of language largely determines how it can change(Janda and Joseph 2003). We have to ruminate on the fact that the grammar of language is a symbolic system of representation while living language is a complex adaptive system generated and regenerated by individuals (Shen 2015). The descriptive capacity of Shen’s theory is compatible with the nature of language being dynamic idiolects alongside a real linguistic history embodied by individual speakers in time and space. The descriptive capacity of Shen’s theory is compatible with the nature of language being dynamic idiolects alongside a real linguistic history embodied by individual speakers in time and space. Only by understanding the change mechanism of Chinese from the perspective of language contact and through the lens of language shift, the variation of Mandarin and emergence of Chinese dialects find their explanations in a salient chain of logic to create a holistic account of Chinese evolution where the intertwined influence of languages finds its manifestation.

Tourism is the fastest growing economic industry and has become one of the leading sources of growth and development in South Africa. However, tourism is in a constant state of flux requiring continuous research to document and analyse these shifting trends. Since 1999, the iSimangaliso Wetland Park (South Africa’s first World Heritage Site) has been using ecotourism as part of its development and conservation strategy. This has resulted in the shift in tourism from what used to be a fishing destination prior 1999 to its current form as a premier ecotourism destination. The aim is to analyse and document the shift from mass tourism to ecotourism in iSimangaliso Wetland Park, using the Eastern Shores as a case study. Through modernism and postmodernism tourism discourse, this dissertation analyses visitor characteristics, behaviour and perceptions of both tourists and tourism businesses over time in an attempt to describe and explain the tourism shift on the Eastern Shores. This research reveals that there has been a distinct tourism shift in the Park from the ‘mass’ fishermen created by the Fordist mode of mass and standardised production to the more ecologically inclined ‘niche’ tourist where the de-differentiation of postmodernism has created diversified forms of tourists and tourism products. Within these broad classifications, this research has discovered the existence of more nuanced tourist profiles. Mass tourists range from the ‘sun, sea, sand, sex and sangria’ tourist to fishermen. Ecotourists on the other hand range from the casual or mainstream ecotourist who practices a shallow form of ecotourism to the dedicated ecotourist whose activities promote conservation and sustainable development allowing for a deeper form of ecotourism. Further, on the Eastern Shores, domestic coastal ‘mass tourists’ have also become more ecologically inclined. Previously these tourists would come for one activity, that is, to relax on the beach or fish. At present, the majority of these tourists now also pursue nature based activities, adventure tourism and/or sightseeing. The changes in the tourists visiting the Eastern Shores are representative of the global shifts in tourism that are currently taking place. Tourism is constantly evolving as part of global capitalism and will continue to shape tourism in iSimangaliso Wetland Park.
Thesis (M.Soc.Sc.)-University of KwaZulu-Natal, Durban, 2013.

abstract: Ephemeral streams in Arizona that are perpendicularly intersected by the Central Arizona Project (CAP) canal have been altered due to partial or complete damming of the stream channel. The dammed upstream channels have experienced decades long cycles of sediment deposition and waterlogging during storm events causing the development of "green-up" zones. This dissertation examines the biogeomorphological effects of damming ephemeral streams caused by the CAP canal by investigating: (1) changes in the preexisting spatial cover of riparian vegetation and how these changes are affected by stream geometry; (2) green-up initiation and evolution; and (3) changes in plant species and community level changes. To the author's knowledge, this is the only study that undertakes an interdisciplinary approach to understanding the environmental responses to anthropogenically-altered ephemeral stream channels. The results presented herein show that vegetation along the upstream section increased by an average of 200,872 m2 per kilometer of the CAP canal over a 28 year period. Vegetation growth was compared to channel widths which share a quasi-linear relationship. Remote sensing analysis of Landsat TM images using an object-oriented approach shows that riparian vegetation cover gradually increased over 28 years. Field studies reveal that the increases in vegetation are attributed to the artificial rise in local base-level upstream created by the canal, which causes water to spill laterally onto the desert floor. Vegetation within the green-up zone varies considerably in comparison to pre-canal construction. Changes are most notable in vegetation community shifts and abundance. The wettest section of the green-up zone contains the greatest density of woody plant stems, the greatest vegetation volume, and a high percentage of herbaceous cover. Vegetation within wetter zones changed from a tree-shrub to a predominantly tree-herb assemblage, whereas desert shrubs located in zones with intermediate moisture have developed larger stems. Results from this study lend valuable insight to green-up processes associated with damming ephemeral streams, which can be applied to planning future canal or dam projects in drylands. Also, understanding the development of the green-up zones provide awareness to potentially avoiding flood damage to infrastructure that may be unknowingly constructed within the slow-growing green-up zone.
Dissertation/Thesis
Ph.D. Geography 2014