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  • 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.
141

Nocturnal rodent populations and associated vegetation with implications of human use at Saguaro National Monument, Arizona

Duncan, Douglas Keith, 1960- January 1989 (has links)
I obtained densities of nocturnal rodents in the saguaro (Carnegiea gigantea) forest of Saguaro National Monument, Arizona with live trapping techniques, in 1984 and 1985. I sampled vegetation density, percent cover, and foliage height diversity. My objective was to determine if humans influenced nocturnal rodents and their habitat. Rodent populations and vegetation were analyzed through 2-way analysis of variance. Few significant differences were determined for rodent numbers between experimental and control plots. My findings show that minimal impact has occurred on rodent populations and on vegetation by humans in Saguaro National Monument.
142

Evolution de la gestion des aires protégées en Guinée : la difficile cohabitation des politiques publiques et des systèmes traditionnels : cas du Parc National du Haut Niger / Evolution of the management of protected areas in Guinea : the difficult cohabitation of public policies and traditional systems : national Park of Upper Niger

Diallo, Mamadou Saïdou 10 March 2011 (has links)
La gestion des aires protégées en Guinée pose le problème de la cohabitation des politiques publiques et des systèmes traditionnels. Censée améliorer la gestion des aires protégées, cette cohabitation s’avère difficile et ne produit pas les résultats escomptés. Pour contribuer à la compréhension de cette difficile cohabitation, cette thèse propose une analyse de l’évolution de la politique de gestion des aires protégées en Guinée, de l’époque précoloniale à nos jours. La démarche utilisée fait appel à plusieurs approches méthodologiques : recueil et analyse de documents historiques et juridiques, recueil et analyses des traditions orales ancestrales relatives à la protection de la nature, observations de terrain, inventaires floristiques, estimations et analyses qualitatives, enquêtes par entretiens semi-directifs. Les résultats obtenus ont permis de retracer et de caractériser les différentes phases de la gestion des aires protégées en Guinée. La gestion des aires protégées précoloniales a connu diverses formes, allant de la sacralisation à la gestion clanique ; elle a varié en fonction des coutumes des populations autochtones de chacune des régions naturelles du pays. Pendant l’époque coloniale, 167 aires protégées ont été mises en place dont 157 forêts classées, 4 parcs de refuge de faune et une réserve naturelle intégrale. A son accession à l’indépendance en 1958, la Guinée a hérité des aires protégées coloniales et a appliqué, jusqu’en 1984, une politique fondée sur la législation forestière de l’administration coloniale. L’Etat s’est approprié les aires protégées dans leur contexte contemporain seulement à partir des années 1984, et a progressivement mis en place de nouveaux dispositifs (législatif et institutionnel) de gestion. Avec l’appui des bailleurs de fonds, il a mis en place plusieurs catégories d’aires protégées (parcs nationaux, réserves de biosphère, aires protégées transfrontalières, zone de conservation) dont la gestion qui se veut participative en associant les populations locales, soufre aujourd’hui essentiellement du manque de financements associé à l’insuffisance de la logistique nécessaire à une gestion opérationnelle et efficace. L’étude du cas du Parc National du Haut Niger révèle que, malgré la reconnaissance et la prise en compte du rôle des communautés traditionnelles (Waton), les populations locales adhèrent à la gestion participative sans grande conviction. Les structures publiques associées à cette gestion ne disposent pas de moyens suffisants pour intervenir de manière efficiente. L’exemple du PHNN illustre l’écart entre le discours dominant qui prône la gestion intégrée des aires protégées et les difficultés de l’Etat à mettre en œuvre une gestion participative. Ces difficultés ne devraient pas pour autant conduire à une remise en cause de la gestion participative, car nos observations et nos enquêtes suggèrent que la stratégie peut fonctionner et faire la preuve de son efficacité si des efforts sont entrepris dans l’appui au développement communautaire et dans la création d’activités génératrices de revenus pour les populations traditionnelles qui mettent leurs savoirs au service de la gestion des aires protégées. / Management of protected areas in Guinea is the problem of the coexistence of public policy and traditional systems. To contribute to the understanding of this difficult cohabitation, this thesis proposes an analysis of the evolution of policy management of protected areas in Guinea, from precolonial times to the present. The approach involves several methodological approaches. The results were used to trace and characterize the different phases of the management of protected areas in Guinea. The state has appropriated the protected areas in their contemporary context only from year 1984. The example of PHNN illustrates the difference between the dominant discourse advocating the integrated management of protected areas and the difficulties of the state to implement a participatory management. Our observations and surveys suggest that the strategy of management override implementation can work if efforts are in supporting community development.
143

Privileged Nature: Ornithologists, Hunters, Sportsmen and the Dawn of Environmental Conservation in Spain, 1850 to 1935

Hanley, Patrick Michael, Hanley, Patrick Michael January 2016 (has links)
This dissertation argues the foundation of Spain's first national park, the Parque Nacional de la Montaña de Covadonga, was the culmination of a four-century-long historical development in which Spaniards redefined the manner in which they conceived of and interacted with nature. The establishment of the Parque Nacional de la Montaña de Covadonga resulted from two different historical processes, the formation of empirical science in Spain and the pursuit of noble hunting, which converged in the late nineteenth-century in the form of species protection and the environmental conscience it reflected. This environmental conscience permeated discourses on Spanish reinvigoration including those of nobleman, sportsman, and politician Pedro José Pidal y Bernaldo de Quirós whose own articulation of this environmental consciousness materialized in the form of the Parque Nacional de la Montaña de Covadonga which legislatively meshed species and landscape protection for the first time in Spain in 1916.
144

Privileged Nature: Ornithologists, Hunters, Sportsmen and the Dawn of Environmental Conservation in Spain, 1850 to 1935

Hanley, Patrick Michael, Hanley, Patrick Michael January 2016 (has links)
This dissertation argues the foundation of Spain's first national park, the Parque Nacional de la Montaña de Covadonga, was the culmination of a four-century-long historical development in which Spaniards redefined the manner in which they conceived of and interacted with nature. The establishment of the Parque Nacional de la Montaña de Covadonga resulted from two different historical processes, the formation of empirical science in Spain and the pursuit of noble hunting, which converged in the late nineteenth-century in the form of species protection and the environmental conscience it reflected. This environmental conscience permeated discourses on Spanish reinvigoration including those of nobleman, sportsman, and politician Pedro José Pidal y Bernaldo de Quirós whose own articulation of this environmental consciousness materialized in the form of the Parque Nacional de la Montaña de Covadonga which legislatively meshed species and landscape protection for the first time in Spain in 1916.
145

The Accidental Place: Louis Armstrong Park Out of Place on the North Side

Estrade, Yvonne 19 December 2003 (has links)
The failed New Orleans Cultural Center Complex was cultural genocide to an area of the neighborhood known as Treme, where a tribute to the jazz great and native son, Louis Armstrong, was planned as an afterthought. The questions remain, was the planning and building of Louis Armstrong Park responsible for the genocide of the Treme neighborhood, is the park an appropriate use of land, and what are the prospects for the park's future? This thesis examines the cultural gumbo of New Orleans history, explores the early days of Louis Armstrong and the development of jazz, sets the record straight by vindicating the Louis Armstrong Park as the culprit for demolition in Treme, and takes a look at "the Back ‘o Town" as a tribute to him.
146

Fingerprints of nature: an Ecological Discovery Centre magnifying and mediating human-nature interactions along the border of the Kruger National Park

King, Bronwyn 29 April 2015 (has links)
This document is submitted in partial fulfilment for the degree: Master of Architecture [Professional] At the University of the Witwatersrand, Johannesburg, South Africa, in the year 2014 / “Architecture embodies humanity’s relationship with the earth” (Hoosey, L. 2012. Pg. 118) There are many threats facing South Africa’s wildlife including the spread of diseases, increased poaching and habitat loss. As a result the Kruger National Park is one of South Africa’s most prized treasures and has become a wildlife recreation, resource and research hub attracting tourists and researchers from around the globe. However, despite the number of visitors to the area, there is an increasing number of local communities specifically on the Southern border of the park, experiencing high levels of unemployment and poverty. As a result, community members are often involved in the harvesting and trade of natural resources through activities such as subsistence poaching and farming. These practices are gradually destroying the natural landscape on the periphery thus posing a significant threat to the park’s biodiversity. In a contest between resource consumption and resource conservation architecture has the opportunity to mediate between the user groups of the region, sparking conversation about conservation. This thesis seeks to provide a building complex which will become the interface between land users and land uses and in so doing become a catalyst in the rehabilitation of the natural landscape. It will provide a platform for an exchange of conservation-based resources, information and skills intended to enhance the experience and understanding of nature. The complex includes a seed bank facility to store and grow a variety of indigenous botanical species to rehabilitate the landscape and support the harvesting of sustainable natural resources. The seed bank is directly linked to the research facility which is dedicated to the investigation and understanding of human-nature interactions along the park’s border. These conservation processes and findings are captured and revealed in the narrative of the ecological museum which forms a large component of the education spaces provided within the project. The three primary programs are consolidated within the design to create a constructed journey through the site. This enables the architecture to become the tour guide that enhances the visitor’s experience through man-made and ecological encounters along the way. In so doing a layering of public/private spaces is established using thresholds to create transition zones which blur the boundaries between inside and outside whilst maintaining a hierarchy of space. As with the building’s program the design is sensitive to its context. The project explores the typologies of the local community, farm structures and botanical nurseries to create an appropriate hybrid between the manufactured and hand crafted. This aesthetic is achieved through the use of locally sourced materials and labour in an attempt to reintroduce the disappearing vernacular building techniques to the region. This exploration is realised in the structural concept of articulating and combining elements of mass, skeleton and skin. In so doing, the architecture becomes a living organism which is climate responsive and houses both people and nature within its form. The structure is designed using the ‘eave’ to create an edge condition that modifies the micro climate of the interior and exterior spaces. It is through these edge conditions that the aesthetic of the building is transformed as species inhabit the structure to establish new ecosystems. This thesis does not attempt to provide a solution to the many threats facing this conservancy, but rather to focus on an area dealing with such challenges and allow architecture to house the means to empower, educate and expose users to the fragility of the natural landscape of the region. It is essential that wildlife conservation is extensively studied and implemented in order for nature to sustainably benefit the communities living off it; tourists travelling to it and conservationists working for it.
147

Spatial and temporal changes of greenness metrics in Kruger National Park from 2000-2010

Mushamiri, Memory 08 May 2013 (has links)
A research report submitted to the Faculty of Science in partial fulfilment of the requirements for the degree of Master of Science. Johannesburg, 31 August 2012. / Unable to load abstract.
148

Statistical approaches towards analysing ungulate movement patterns in the Kruger National Park

Goodall, Victoria Lucy 12 June 2014 (has links)
In this thesis I investigate the application of various statistical approaches towards analysing time series data collected using GPS collars placed on three ungulate species in the same region of the Kruger National Park, South Africa. Animal movement tracking is a rapidly advancing area of ecological research and large datasets are being collected with GPS locations of the animal, with shorter periods between successive locations. A statistical challenge is to segment the movement paths into groups which correspond to different behavioural activities. The aim of my study was to investigate and compare alternative statistical approaches for analysing GPS data and to establish the best statistical framework for interpreting these large herbivore movements. The focus was on which methods are the most appropriate for these animals and the comparison of the movement patterns across species and season. Independent Mixture, Hidden Markov and Bayesian State-Space Models were used to analyse the hourly and daily movements of sable antelope, buffalo and zebra. Mixture Models provide a basic clustering technique to segment the movement paths and identify different underlying groups within the data assumed to correspond to different behavioural states. Posterior probabilities of group membership are used to allocate movements between successive locations to different states. This method ignores the dependence between successive movements. Hidden Markov models (HMMs) use a time series technique and include a dependency between successive observations via a Markov process. Extensions to the HMMs were applied to allow for the inclusion of seasonal covariates and irregular time gaps between successive observations caused by missing locations. A Bayesian state-space model fits a random walk using MCMC methods. The results were very similar to the HMMs but were more challenging to fit and required much more processing time. In the absence of informative prior information, the Bayesian method does not provide any improvement on the HMMs. The HMMs perform slightly better in terms of state allocation accuracy than the Mixture Models. However Mixture Models perform acceptably if only a straightforward clustering of the observations is required. However, if a more robust method is required, the HMMs are relatively easy to fit and extend, allow for investigation of the state switching probabilities and are recommended as the best method for analysing this type of data.
149

Seed fate and density of soil seed banks of four Acacia species in the Kruger National Park, South Africa

Stelli, Samanta Adele 17 January 2012 (has links)
MSc., Faculty of Science, University of the Witwatersrand, 2011 / ABSTRACT Observations of the changes in woody plant density in the Kruger National Park (KNP) over 58 years have shown an increase in large woody plant density on granite substrates, which is attributed to fire and herbivore density. Woody plants persist in areas with frequent fires, herbivory and drought by resprouting or protecting seeds in the ground. Soil seed banks, which are stores of seeds below ground or in leaf litter, provide 'insurance' for trees and allow populations to persist in unfavourable environments. No comprehensive studies have been conducted on soil seed bank ecology of Acacia species in the Kruger National Park, a research gap which this study aimed to fill. The spatial distribution and density of in situ soil seed banks for four Acacia species, A. grandicornuta, A. nilotica, A. senegal and A. tortilis was assessed in the Skukuza land system of the KNP, South Africa. In situ soil seed banks were quantified for eight mature trees per species during 2005/2006. Greenhouse and field seed burial trials were carried out for one year and 16 months respectively, between 2005 and 2007, to investigate the persistence of Acacia seeds over an extended period of time. Post-dispersal seed predation of Acacia seeds was investigated during July 2006 in six demarcated grids within 15 km of Skukuza. Overall soil seed bank density differed significantly among species, being highest for A. tortilis (19.5 ± 6.4 seeds m-2), followed by A. grandicornuta (12.1 ± 6.9 seeds m-2), A. nilotica (4.9 ±1.8 seeds m-2) and lowest for A. senegal (0.6 seeds ± 0.4 seeds m-2). Generally, seed bank density decreased with depth in the soil and distance from the centre of the tree canopy. Seed bank density increased significantly with a decrease in soil compaction for A. senegal only, while it was not related to over-storey canopy shading or herbaceous biomass for any of the species. No significant relationship was found between seed bank density and tree characteristics such as stem diameter, bark thickness or tree canopy area for any of the species. Viability of seeds from the seed bank decreased between species as follows: A. tortilis (77% of 142 seeds), A. nilotica (61% of 39 seeds), A. grandicornuta (58% of 87 seeds), and A. senegal (0% of 4 seeds). For all species with viable seeds, viability decreased with distance from the centre of the tree canopy. Bruchid beetle predation (assessed on 100 newly produced seeds) was low for all four species. Fifty seeds each of A. grandicornuta, A. senegal and A. tortilis and 100 A. nilotica seeds were destroyed by fire during the field seed burial trial, of which four hundred seeds/species were used. Of the remaining seeds, 15% of A. senegal, 19% of A. grandicornuta, 34% of A. nilotica and 66% of A. tortilis remained intact after 16 months in the field. Of these, 65% of A. tortilis, 27% of A. nilotica, 5% of A. grandicornuta and no A. senegal seeds were still viable. The percentage of remaining intact, viable seeds was highest under tree canopy cover and buried for A. tortilis (86%), A. nilotica (39%) and A. grandicornuta (6%), but the micro-site placement of seeds had a significant effect on viability for A. nilotica only (d.f. = l; χ2 = 7.5; P = 0.006). In the greenhouse seed burial trial (150 seeds/species/treatment), one percent of the total seed lot germinated, which was 2.9% of A. grandicornuta, 0.7% of A. senegal and 0.2% of both A. nilotica and A. tortilis. A. tortilis had the highest percentage of remaining intact, viable seeds (92.2%), followed by A. nilotica (58.3%), A. grandicornuta (57.6%) and A. senegal (0%). The number of remaining intact, viable seeds was highest when watered with the average rainfall (327 seeds), followed by the highest (314 seeds) and lowest rainfall (296 seeds). There was no association between rainfall treatments and the number of remaining intact, viable seeds for any of the species, except for A. grandicornuta where the number of remaining intact, viable seeds increased significantly with the average rainfall. Across six grids in the Skukuza land system, A. grandicornuta was the most dominant woody plant of six study species, followed by Dichrostachys cinerea, A. tortilis, A. nilotica, A. senegal and A. nigrescens. Woody plant density in grids varied between 226 plants ha-1 (Grid 3) to 1618 plants ha-1 (Grid 5), with a mean density of 862 ± 195 plants ha-1. Overall, woody plant species diversity was low (Shannon Wiener Index, 1.8 ± 2.8; Evenness Index, 0.7 ± 0.02; Simpson's Reciprocal Index, 4.5 ± 0.6). The dung of nine species of large herbivore was recorded across all six grids. Large herbivores favoured seeds of indehiscent (55 A. tortilis seeds and 11 A. nilotica seeds) over dehiscent pods (1 A. grandicornuta seed). Only 9% (five A. tortilis seeds and one A. grandicornuta seed) of the 67 seeds extracted from dung germinated after a six-week germination trial. Less than half the remaining ungerminated A. nilotica seeds (46%) and A. tortilis seeds (40%) tested viable. There was no correlation between the number of termitaria recorded and the number of Acacia trees growing on them (r = 0.07). Termite mounds occupied 0.0009 ± 0.0003 ha per grid matrix (0.8%). Only four rodent species were recorded across all six grids, Mastomys coucha (multimammate mouse), Rhabdomys pumilio (striped mouse), Aethomys chrysophilus (red veld rat) and Tatera leucogaster (highveld gerbil). Rodent species diversity was low (Shannon Wiener Index, 0.6 ± 0.2; Evenness Index, 0.6 ± 0.2; Simpson's Reciprocal Index, 1.9 ± 0.3). In the field cafeteria trial there was a significant difference in the percentage of seeds removed between seed species (P < 0.05; F = 2.8; d.f. = 3, 236). There was a significant difference in the percentage of seeds removed from trays placed under vegetation cover compared with trays placed in the open (P = 0.034). This study suggests that A. grandicornuta, A. nilotica and A. tortilis seeds form short-term persistent seed banks, while A. senegal seeds are transient and do not form seed banks. Seeds of several woody plants were ingested by large herbivores and selected by rodents. The relevance of soil seed banks to regeneration of Acacia trees needs to be evaluated by investigating whether these species rely more on seed production or resprouting for individual recruitment into tree populations. Once this issue is clarified the effect of certain factors on seed fate and consequently, recruitment of individuals into plant populations, can be more clearly understood. This will assist in managing and understanding these potentially encroaching species in the Kruger National Park, South Africa.
150

Mammal utilisation of artificial water sources in the central Kruger National Park: contemporary seasonal patterns and implications for climate change scenarios

Trent, Amy Jean January 2016 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Master of Science. Johannesburg, August 2016 / Monitoring the status and abundance of mammals, as well as establishing threats to biodiversity in different areas, is an essential management requirement in protected areas. Monitoring mammal species can assist in determining species interactions, patterns of behaviour and is important for further research, policy and management strategies. Water provision has implications for the preservation of wildlife, and is thus a management concern. Numerous studies monitoring mammal water utilisation patterns have employed traditional data collection methods, which are restricted primarily to diurnal observation during specific time intervals. Given the projected future impacts of global climate change on regional water availability, it is essential to investigate current water usage by mammals in the Kruger National Park (KNP), so as to better ascertain likely future water requirements under climate change scenarios. The use of remote photography for scientific observation, investigation and monitoring has many potential benefits, and an innovative and relatively new method through which one can observe mammal water source visitation patterns, is through the use webcams. There has been comparatively little research on mammal water requirements and visitation patterns at water provisioning sites using remote photography as a data collection method. Further to this, there is a gap in our knowledge concerning how daily climate variables (viz. temperature and rainfall) and astronomical conditions control water source visitation patterns at the finer temporal scale. This research primarily contributes to understanding contemporary water source visitation patterns and how this will influence future management decisions. At a broader scale, determining recent visitation patterns is critical in the context of projected future climatic changes and the associated water requirements for mammals of KNP. Webcam images were obtained for the period March 2012 - March 2014, captured at two artificial water sources in the central KNP. A clear divide is exhibited between herbivore and carnivore visitation patterns, with herbivores exhibiting exclusively diurnal patterns and carnivores’ nocturnal patterns. Significant relationships with Tavg intervals demonstrate that the majority of herbivores are shifting their visitation periods earlier in the day per 5°C increase in mean daily temperature, while the majority of carnivores are shifting their visitation periods later in the night per 5°C increase in mean daily temperature, however there is variability of species responses across the two study sites. Under the highest Tavg interval (30°C - 35°C) impala, warthog, southern giraffe, African buffalo and plains zebra exhibit a shift to earlier visitation by 1 – 6 hours, forcing them to utilise the water sources outside of their preferred temporal range. The influence of the timing of rainfall events indicates that the mean number of individual species sightings is significantly larger on days before rainfall compared to days after rainfall. The study highlights that waterdependent herbivores utilise the artificial water sources in relative proportion to their abundance in the central KNP, while water-independent herbivores are avoiding these artificial water sources. The findings of this research could be used to supplement current water provisioning guidelines and plan for water provisioning efforts in future. / TG2016

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