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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.
1

Conservation and land use planning applications in Gabon, Central Africa

Lee, Michelle E. January 2014 (has links)
Spatial prioritization and systematic conservation planning methods are designed to improve land use decisions and conservation outcomes, yet remain underutilized in many biologically-rich places that need them most. This thesis applies the theory and methods developed in the discipline of spatial prioritization to conservation and land use decisions in the Central African country of Gabon. Creating a spatial information base of priority species, habitats and land uses in a region that is notoriously data-poor, I reveal that many features important for both conservation and natural resource production are highly localized; their coincidence has important implications for management. Setting conservation targets for species and habitats, I find that representation in existing protected areas is relatively low, and identify a number of near-optimal solutions that meet all targets, with minimal impact on land used for local livelihoods. I distill these solutions down to a handful of critical biodiversity sites that are top priority to protect, and make management actions explicit for the species and habitats they contain. To make the work more widely applicable, I also develop a novel method to identify where field surveys are most likely to improve decisions about protected area expansion, providing decision-makers with more options of places that could be protected to achieve conservation goals. This study contributes to the research, development and practice of conservation prioritization and spatial planning, particularly in data-poor contexts like Gabon, which still have a wealth of biodiversity, and need to carefully plan for its conservation alongside development.
2

Patterns of animal endemism in the Maputaland-Pondoland-Albany biodiversity hotspot.

Perera, Merennage Sandun Jayalal. 12 September 2014 (has links)
The Maputaland-Pondoland-Albany (MPA) hotspot, as is the case of all such global biodiversity hotspots, has primarily been recognised based on its high floristic endemism and delimited intuitively. Boundaries of global biodiversity hotspots have seldom been empirically tested in terms of species distribution patterns and only a few have been examined for patterns of animal endemism. This thesis presents the results of a zoogeographical study of all five major vertebrate groups and selected invertebrate groups in south-eastern Africa, refining the delimitation of the MPA hotspot and identifying areas and centres of endemism within and around it. It also provides zoogeographical regionalisation schemata for the whole of south-eastern Africa. The study employed methods of, (a) preliminary qualitative identification of “Endemic Vertebrate Distributions”, (b) phenetic clustering of operational geographical units based on species incidence matrices, using the Jaccard’s coefficient of similarity and the Unweighted Pair-Group Method using Arithmetic means (UPGMA) clustering algorithm, (c) Parsimony Analysis of Endemicity, and (d) ArcGIS-based mapping of various measures of endemism (e.g. narrow endemism and weighted endemism). The results reveal that the MPA hotspot, though defined so due to its exceptional floristic endemism, is a hotspot for the endemism of animals too, especially for the herpetofauna and invertebrate groups like the velvet worms, land snails and many others. But the current boundary of the hotspot is arbitrarily defined and not exactly matching the patterns of animal endemism (and, likely, neither those in plants). Hence, a greater Maputaland-Pondoland-Albany (GMPA) region of animal endemism is proposed as a broad priority region of conservation concern, while centres of endemism within the GMPA are identified and patterns of quantitative measures of endemism are mapped. The study also proposes a zoogeographical regionalisation placing the GMPA and Highveld regions at the province rank in the global zoogeographical hierarchy, within the south east African dominion, also describing zoogeographical districts and assemblages nested within each. Results from the vertebrate and invertebrate analyses reveals the possibility of a common zoogeographical regionalisation for south-eastern Africa. The study emphasises the importance of quantitative biogeographical methodologies in conservation biogeography, in addition to their uses in the theoretical/descriptive biogeography. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2013.
3

Historical biogeography of the tribe Platypleurini Schmidt, 1918 (Hemiptera: Cicadidae) with a focus on Southern Africa

Price, Benjamin Wills January 2010 (has links)
With our contemporary biota under increasing threat of extinction, it is of interest to understand where, why and how biological diversity is generated. If focussed on appropriate taxa, phylogeographic and phylogenetic studies can assist in the identification of both places and processes central to the origin and maintenance of biological diversity. It is explained why southern Africa presents a perfect test-bed for exploring such mechanisms of diversification and why cicadas (Hemiptera: Cicadidae) have proved very suitable tools for studies of historical biogeography. This study then exemplifies these points by providing the first large-scale investigation of the historical biogeography of the tribe Platypleurini Schmidt, 1918, with emphasis on the genus Platypleura Amyot & Seville, 1843 in southern Africa. Standard methods of DNA sequencing provided data from portions of the mitochondrial small subunit ribosomal 16S RNA (16S) and cytochrome oxidase subunits I (COI) and II (COII); and the nuclear elongation factor 1 alpha (EF-1α) from 400 ethanol-preserved specimens. These data were analysed using standard phylogenetic methods and a time scale of diversification was estimated using a Bayesian framework and both fossil data and DNA substitution rates. The results showed that the tribe is too recent to be of Gondwanan origin. The lack of monophyly of the genera represented in both Asia and Africa showed that the tribe needs formal taxonomic revision. Diversification of the African platypleurine genera coincides with aridification in the early Oligocene. Dispersal of Asian platypleurine taxa coincides with the meeting of Africa and Eurasia in the mid-Oligocene. Two radiations within African Platypleura are hypothesised; one distributed over most of sub-Saharan Africa and the second restricted to southern Africa, with clades restricted within regional biomes. Within each of the three focal biomes, cryptic taxonomic diversity was confirmed, suggesting that, even in relatively well understood groups such as the southern African platypleurine cicadas, molecular data can identify further diversity. Although each focal taxon was restricted to non-overlapping biomes, comparison of the three biomes highlighted interactions between palaeoclimates and fixed landscape features (coastal topography, river catchments and escarpments) as causative agents of vicariance, dispersal, extinction and diversification of these volant insects. The results of using co-distributed species for comparative study cautions against making inferences based on single-taxon datasets and highlights the need to use many, evolutionarily independent taxa when identifying mechanisms of diversification. The dating analyses imply that within-species lineage diversification occurred overwhelmingly within the Pleistocene, a trend that is being increasingly recognised in print for other biota. Some caveats about using phylogenetic approaches to estimate ancestral areas are illustrated. Several recommendations are made regarding additional taxa and data sources for understanding the origin and maintenance of biological diversity.
4

Bioprospecting and intellectual property rights on African plant commons and knowledge: a new form of colonization viewed from an ethical perspective

Lenkabula, Puleng 09 1900 (has links)
This study engages in an ethical examination of contemporary socio-ecological and economic issues which takes seriously the plight of Africa, African communities, indigenous knowledge and biodiversity. It studies the impact of bioprospecting, biopiracy and intellectual property rights regimes on the protection, use, access to, and conservation of biodiversity and indigenous knowledge in Africa. The study also examines the ways in which northern multinational pharmaceutical and biotechnology companies and their agents prospect and convert African resources (biological commons and indigenous knowledge) into their intellectual property as well as private property. It argues that the transfer of African biological commons and indigenous knowledge is exacerbated by economic globalisation and the neo-colonial mentality of conquest concealed under the guise of commerce. The study demonstrates through concrete case studies the tactics used by northern multinational corporations to claim these resources as their intellectual property rights and private property. It observes that the privatisation of biological commons and indigenous knowledge only brings about nominal or no benefits to African communities who have nurtured and continue to nurture them. It also observes that this privatisation results in fewer benefits for biodiversity as they lead to the promotion of monoculture, i.e. commercialisation of all things. To address the injustice and exploitative implications of bioprospecting, biopiracy and intellectual property rights, the study recommends the adoption and implementation of the African model law, the establishment of defensive intellectual property rights mechanisms, and the strategy of resistance and advocacy. It suggests that these measures ought to be grounded on the African normative principle of botho and the Christian ethical principle of justice. / Systematic Theology and Theological Ethics / D.Th.(Theological Ethics)
5

Bioprospecting and intellectual property rights on African plant commons and knowledge: a new form of colonization viewed from an ethical perspective

Lenkabula, Puleng 09 1900 (has links)
This study engages in an ethical examination of contemporary socio-ecological and economic issues which takes seriously the plight of Africa, African communities, indigenous knowledge and biodiversity. It studies the impact of bioprospecting, biopiracy and intellectual property rights regimes on the protection, use, access to, and conservation of biodiversity and indigenous knowledge in Africa. The study also examines the ways in which northern multinational pharmaceutical and biotechnology companies and their agents prospect and convert African resources (biological commons and indigenous knowledge) into their intellectual property as well as private property. It argues that the transfer of African biological commons and indigenous knowledge is exacerbated by economic globalisation and the neo-colonial mentality of conquest concealed under the guise of commerce. The study demonstrates through concrete case studies the tactics used by northern multinational corporations to claim these resources as their intellectual property rights and private property. It observes that the privatisation of biological commons and indigenous knowledge only brings about nominal or no benefits to African communities who have nurtured and continue to nurture them. It also observes that this privatisation results in fewer benefits for biodiversity as they lead to the promotion of monoculture, i.e. commercialisation of all things. To address the injustice and exploitative implications of bioprospecting, biopiracy and intellectual property rights, the study recommends the adoption and implementation of the African model law, the establishment of defensive intellectual property rights mechanisms, and the strategy of resistance and advocacy. It suggests that these measures ought to be grounded on the African normative principle of botho and the Christian ethical principle of justice. / Systematic Theology and Theological Ethics / D.Th.(Theological Ethics)
6

Analyse des structures spatiales des données de distribution phytogéographique des Acanthaceae en Afrique centrale / Analysis of the spatial structures of the data of phytogeographic distribution of the Acanthaceae in central Africa

Koffi, Kouao Jean 04 July 2008 (has links)
Les données phytogéographiques reflètent la variabilité spatiale de la diversité des espèces et constituent donc un outil important dans le développement des politiques de conservation. Afin de stimuler et de valoriser le concept des systèmes phytogéographiques, cette étude dont le thème est «Analyse des structures spatiales des données de distribution phytogéographique des Acanthaceae en Afrique centrale» s’est donnée pour but (1) d’analyser la distribution spatiale de la famille des Acanthaceae en Afrique Centrale (R.D. Congo, Rwanda, Burundi) ;(2) de comparer cette distribution avec les théories phytogéographiques de Robyns (1948), White (1979, 1986) et Ndjele (1988); (3) d’utiliser les modèles de distribution spatiale comme support (outil) pour évaluer l'impact humain sur le paysage et la diversité; (4) d’identifier les espèces indicatrices potentielles des territoires phytogéographiques; (5) de mettre en évidence le phénomène de vicariance; et (6) de quantifier l’impact de la fragmentation du paysage forestier en Afrique centrale. Dans cette étude, deux niveaux de résolution spatiale ont été considérés: les systèmes phytogéographiques et les systèmes de maillage. Un système d’information géographique a été utilisé pour réaliser des cartes de distribution spatiale de chaque espèce. Le choix des Acanthaceae de l’herbier du Jardin Botanique National de Belgique (BR), a été dicté par le faite qu’elle a subit une révision systématique et par le nombre important de ses échantillons. L’aspect floristique a révélé 9181 échantillons, récoltés de 1888 à 2001 par environ 427 collecteurs en R.D. Congo, au Rwanda et au Burundi représentant 48 genres, 310 espèces et 6362 localités. La carte de distribution spatiale de l’ensemble des échantillons a mis en évidence les niveaux de prospection. Certains territoires phytogéographiques ont été plus explorés que d’autres. Les entités phytogéographiques les plus explorées et donc les plus diversifiées sont le centre régional d’endémisme Afromontagnard, incluant la Mosaïque régional du lac Victoria, et le centre régional d’endémisme Zambézien. Les cartes de distribution de chaque espèce mettent en évidence les patrons de distribution spatiale. Certaines espèces ont une large distribution alors que d’autres sont inféodées à certaines zones spécifiques. Ces dernières, qualifiées « d’espèces uniques » ou « espèces caractéristiques » peuvent être utilisées comme des bio-indicateurs pour stimuler et valoriser le concept de systèmes phytogéographiques dans la politique de la conservation. En utilisant uniquement la famille des Acanthaceae, il a été montré que l’impact de la fragmentation du paysage forestier est très important. Les espèces inféodées à une région phytogéographique sont des espèces vulnérables. Elles peuvent disparaître si leur biotope est détruit. La distribution potentielle, basées sur les localités de récolte et les variables environnementales, ont été réalisées afin de mieux déterminer les niches écologiques des espèces et les cas de vicariance. Deux types de vicariance ont été mis en évidence à travers les systèmes phytogéographiques de Robyns (1948) et de White (1979, 1986), au niveau générique et spécifique: la vicariance écologique et la vicariance géographique. La vicariance écologique s’applique aux espèces ou sous-espèces récoltées dans les mêmes territoires phytogéographiques tandis que la vicariance géographique concerne les espèces ou sous-espèces récoltées dans des territoires phytogéographiques séparés. L’analyse des cas de vicariance a mis en relief les zones de spéciation. L'analyse de classification hiérarchique a montré que les Acanthaceae suivent mieux le système phytogéographique de White (1979, 1986) que ceux proposés par Robyns (1948) et Ndjele (1988). Pour mieux valoriser cette approche, cette méthodologie doit être appliquée à d’autres familles largement récoltée en R.D. Congo, au Rwanda et au Burundi comme la famille des Rubiaceae, des Mimosoideae, afin de (1) synchroniser toutes les bases de données pour mieux mettre en évidence le degré d’exploration, les espèces à amplitude écologique restreinte (espèces uniques) et (2) de permettre d’identifier des zones prioritaires pour la conservation. <p><p><p>Phytogeographic data reflect the spatial variability of plant diversity and constitute consequently a potential tool for conservation policy development. In order to stimulate and valorise the concept of phytogeographic systems, this dissertation entitled “Analysis of the spatial pattern of phytogeographic data of Acanthaceae in Central Africa” aims (1) to analyse the spatial distribution of the Acanthaceae family in Central Africa (Democratic Republic of the Congo, Rwanda, Burundi); (2) to compare this distribution with the known phytogeographic theories of Robyns (1948), White (1979, 1986) and Ndjele (1988); (3) to use the spatial distribution models as a tool for evaluating the human impact on landscapes and diversity; (4) to identify potential indicator species of the phytogeographic territories; (5) to evidence the phenomenon of vicariance; and (6) to quantify the impact of the fragmentation of forested landscapes in central Africa. In this study, two levels of spatial resolution have been considered: the phytogeographic systems themselves and a system of grid cells. A geographic information system has been used to draw maps of the spatial distribution of every species. The choice to analyse the Acanthaceae family of the herbarium of the National Botanical Garden of Belgium (BR) has been justified by the systematic revision of this collection and by its huge number of samples. The data set contained 9181 samples, collected between 1888 and 2001 by about 427 collectors in the Democratic Republic of the Congo, Rwanda and Burundi ;the samples represented 48 genera, 310 species and 6362 geographic positions. The maps showing the spatial distribution of all samples pooled evidenced the different levels of exploration of the study area. Certain phytogeographic territories have been explored more intensely than others. The mostly explored zones, consequently also denoted as the most diverse ones, were the Afromontane regional centre of endemism, including the regional mosaic of Lake Victoria, and the Zambezian regional center of endemism. Species distribution maps evidenced the spatial patterns of species presence. Certain species showed an overall distribution while others were clearly bound to particular territories. The latter species, denoted as “unique species” or “characteristic species” could be used as bio-indicators to stimulate and valorise the concept of the phytogeographic systems in the framework of conservation policy development. By means of the Acanthaceae family, it has been shown that the impact of forest fragmentation will be considerable; species bound to a specific phytogeographic zone are assumed vulnerable; they will disappear when their biotopes are destroyed. The potential distribution of the species, based on the geographic position of the samples and on environmental data, have been generated in order to describe more precisely the ecological niches of the species involved and to detect cases of vicariance. Two types of vicariance have been found using the phytogeographic territories of Robyns (1948) and White (1979, 1986) at the genus and the species levels: ecological vicariance and geographic vicariance; the former type involves species or subspecies observed in the same phytogeographic region while the latter type involves species and subspecies not found in the same territory. This analysis enabled us to identify zones of speciation. A cluster analyses showed that the spatial distribution of the Acanthaceae data corresponded more closely to the phytogeographic system of White (1979, 1986), than to those proposed by Robyns (1948) or Ndjele (1988). In order to valorise our approach, the current methodology should also be applied to other families widely collected in the Democratic Republic of the Congo, Rwanda and Burundi, such as the Rubiaceae or Mimosoideae families, this (1) to synchronise all data bases for a more profound understanding of the degree of exploration and of the existence of species with a limited ecological amplitude (unique species), and (2) to enable the identification of zones that should be prioritised for conservation. <p> / Doctorat en Sciences / info:eu-repo/semantics/nonPublished

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