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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.
151

The influence of location on the structure and functioning of private land conservation networks in the Western Cape province of South Africa

Baum, Julia January 2016 (has links)
Protected areas are an important tool for biodiversity conservation. Statutory protected areas are, however, perceived to currently be insufficient in extent and functioning for achieving conservation goals. Conservation action on privately owned land plays an increasingly vital role in expanding the global conservation estate. Private Land Conservation Areas (PLCAs) exist with internal properties and external contexts and do not occur isolated in space and time. They can thus best be described as linked social-ecological systems. Little comprehensive work has yet been done concerning the structure and functioning of PLCAs. However, an understanding of their emergence, long-term persistence and contribution to conservation is highly relevant. How can PLCAs maintain their identity against disturbances in order to be resilient into the future? Spatial patterns and relationships determine the answer to this question. Geographical location influences the private conservation estate through different drivers, namely biophysical conditions, network connections and membership, as well as socio-economic conditions. I thus used a comparative, spatially explicit and holistic approach to better understand spatial resilience of PLCAs in the Western Cape Province of South Africa as case study region. The approach was based on assessing representative measures for four elements of system identity (being components, relationships, sources of continuity, and sources of innovation). I expected that geographical location and spatial variation in social-ecological factors strongly influence PLCA types, socio-economic interaction networks among protected areas and other stakeholders, contribution to conservation by PLCAs and their ecotourism performance. Information and data for this research were obtained from personal interviews conducted with owners and managers of 70 PLCAs across the province. Additional data were derived via conservation authorities and online tools. My findings show that the identity and resilience of PLCAs are strongly dominated by the influence of spatial location and heterogeneity in factors such as ecological features or socioeconomic context. I was able to verify existing PLCA types, namely game and habitat reserves, which strongly depended on the biophysical context. Visitation rates were influenced by location which determined the adopted corporate model of PLCAs. Clear neighbourhood effects emerged in socioeconomic interaction networks, which further highlighted great potential to enhance collaboration across scales. PLCAs provided a substantial contribution to conservation targets in terms of importance (covering critical biodiversity areas) and urgency (protecting ecosystems of threatened status). My findings will be valuable to highlight opportunities for more effective conservation in the study region, and to advance insights into the spatial resilience of social-ecological systems.
152

Calculating Amazonia: the politics of calculative abstractions in Peru’s tropical rainforest governance

Romero Dianderas, Eduardo Javier January 2022 (has links)
In this dissertation, I examine how massive technocratic investments deployed over the last twenty years are changing the ways in which Peru’s tropical rainforests come to be experienced, known and governed in the context of climate change and biodiversity loss. I focus on the region of Loreto, Peru’s largest Amazonian region, in order to explore recent changes in two realms of tropical rainforest governance: the traceability of tropical timber and the georeferentiation of Indigenous lands. Drawing on 24 months of ethnographic and archival fieldwork following the activities of state bureaucrats, loggers, Indigenous peoples, land surveyors and other human and more-than-human actors, I show how such interventions have focused on stabilizing elusive calculative abstractions that I call metaphysical objects: objects such as lines, points or volumes that cannot be directly experienced through the senses, but whose continuous stabilization through everyday technocratic labor carries the promise of making rainforest information ever more coordinated, standardized and self-consistent. As emerging regimes of global environmental governance increasingly demand modes of epistemic coordination and standardization at planetary scales, I argue that metaphysical objects are becoming themselves important terrains of political struggle where what comes to be at stake are the terms of their always precarious stabilization. In this context, I contend that following the speculative processes by which metaphysical objects are precariously stabilized across tropical rainforest, Indigenous communities and state offices is crucial to understand the political and epistemic dilemmas that surround emerging regimes of global environmental governance in the age of climate change and biodiversity loss.
153

Understanding urban ecologies in the context of local biodiversity and open space conservation agendas in two South African cities

Bux, Quraisha 06 May 2019 (has links)
South Africa is the third most biologically diverse country in the world and has developed advanced biodiversity legislation and policies to protect its natural environment. Biodiversity is the natural wealth of all living things on earth, from which a multitude of ecosystem services that sustain life emanate. The dramatic shift towards urban living however, places tremendous pressure on these biological resources. Local government has received international recognition as the level of government that is key to securing long-term global sustainability. The cities of Cape Town and Durban in South Africa have each developed their own biodiversity and open space conservation systems to conserve and protect the remaining biodiversity and open spaces within their respective municipal boundaries. The aim of this research was to explore the local biodiversity and open space conservation strategies in these two cities, with a view to understanding: (1) the informants, and emerging form, of urban conservation strategies in these two cities in light of their variable biophysical templates and histories; and (2) the physical landscape pattern in each city, and from this information, infer likely ecological outcomes, for these two cities. The study made use of both qualitative and quantitative research methods. The results reveal that while both cities are facing similar issues in terms of biodiversity loss and natural habitats becoming increasingly fragmented, the way in which these issues manifest in these different cities is unique. The City of Cape Town is highly developed and fragmented but has more land secured under its conservation plan compared to the City of Durban. Durban however, has a large rural land component which remains under the governance of traditional leaders. The study reveals that there are many factors that play a role in the development and success of conservation plans, including: the local context, biophysical templates, city histories, social informants of how these plans emerge and evolve, contemporary governance structures as well as local pressures. Biodiversity conservation in South African cities still faces many challenges which need to be overcome in the near future. These solutions will need to be city specific.
154

Biodiversity conservation and state sovereignty

Echeverria, Hugo. January 2005 (has links)
No description available.
155

Genetic resources under the CBD and TRIPS : issues on sovereignty and property

Dajani, Ola Fouad January 2002 (has links)
No description available.
156

Land Use, Diverse Values, and Conservation Practice in the Periphery of Makira Natural Park, Northeastern Madagascar

Cullman, Georgina January 2013 (has links)
This dissertation examines the intent and reality of a conservation project that aims to be participatory and to provide benefits to local landholders. I make a contribution to research about the social impacts of conservation projects as well as to scholarship that aims to improve conservation policy and practice. Using both ethnographic and ecological methods, I explored the multiple and contested values related to land use. Changing local land use practices, especially reducing swidden agriculture, is a major focus of conservation interventions in the region. The conservation project has framed this change as a technical problem, and has devised economic incentives to shift local people's land use. Because of the dissertation's interdisciplinary approach, and the sometimes contentious relations between conservation biologists and practitioners and social scientists, I begin with a review of the challenges to achieving interdisciplinary collaboration. In the second chapter, I seek to understand how a government policy that was meant to benefit forest-dwelling communities was instead experienced as disempowering and restrictive. Chapter 3 uses land-use scenarios to evaluate the multiple objectives of Makira Natural Park (i.e., biodiversity conservation, climate change mitigation and sustainable livelihoods support) through the lens of ecosystem services, concluding that the best strategy to meet Makira's multiple objectives is to support a broad diversity of land use types rather than eliminating some and favoring others. In Chapter 4, I demonstrate how the conservation project's reliance on an economic model of human motivation to shift land use practices relies on a set of values that are not necessarily shared by local landholders, which explains in part their lack of traction to date. I conclude with a series of recommendations for how to transform conservation practice in Makira to make it more effective, culturally appropriate, and just.
157

A biodiversity conservation policy and legal framework for Hong Kong

Felley, Mary Louise. January 1996 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
158

The relative performance of surrogate measures for viable populations

Solomon, Mariaan. January 2000 (has links)
Thesis (M.Sc.(Zoology))--University of Pretoria, 2000. / Abstract in English. Includes bibliographical references.
159

Evaluation of genetic diversity of flowering dogwood (Cornus florida L.) in the eastern United States using microsatellites.

Hadziabdic, Denita, January 2010 (has links)
Thesis (Ph. D.)--University of Tennessee, Knoxville, 2010. / Title from title page screen (viewed on July 13, 2010). Thesis advisor: Robert N. Trigiano. Vita. Includes bibliographical references.
160

Untangling mechanisms structuring insect diversity patterns in the Cape Floristic Region : the Restionaceae and their herbivores

Kemp, Jurene Ellen 12 1900 (has links)
Thesis (MSc)--Stellenbosch University, 2014. / ENGLISH ABSTRACT: Research into the patterns and drivers of insect diversity in the Cape Floristic Region (CFR) lags far behind that of plants. Here I sample insect herbivore communities on a dominant plant family (Restionaceae), and use a spatially nested sampling design and network analysis to evaluate the association between plant and insect diversity in the CFR. I find that plant species richness predicts insect richness better than environmental factors. Turnover in insect communities is strongly associated with turnover in plant (both species and phylogenetic) communities at both local and regional sampling scales, suggesting insect host specificity. Plant communities unsurprisingly show significant turnover at small spatial scales (i.e. communities situated 0.1-3 km apart show significant turnover and may be tied to ecological niches). Insects show a similar pattern, but the decrease in community overlap is more gradual, suggesting many insects can utilise multiple (possibly closely related) hosts while plants are tied to particular niches. The emergent structure of multiple interaction networks is spatially and temporally invariant, despite high compositional change. However, the internal structure of the networks shows variation (i.e. interactions show spatial and temporal turnover). Seasonal interaction turnover is driven by a turnover in herbivores and by herbivore host switching. Spatially the turnover in interactions is driven by simultaneous turnover in both plants and insects, either suggesting that insects are host specific, or that both groups exhibit parallel responses to environmental gradients. Spatial interaction turnover is also driven by a turnover in plants, showing that many insects can utilise multiple (possibly closely related) hosts and have wider distribution ranges than their host plants. Results point toward insect host specificity, but probably not at the species level, as the primary mechanism structuring insect communities associated with the Restionaceae in the CFR. / AFRIKAANSE OPSOMMING: Navorsing wat verband hou met die patrone en meganismes wat insekdiversiteit in the Kaapse Blommeryk (KBR) hou nie pas met dié van plante nie. In hierdie studie neem ek insekmonsters binne een van die dominante plantfamilies (Restionaceae), en gebruik ‘n ruimtelik geneste ontwerp en netwerkanalise om die verbintenis tussen plant- en insekdiversiteit te evalueer. Ek vind plantrykheid voorspel insekrykheid beter as enige omgewingsfaktore. ‘n Omset in in insekgemeenskappe is sterk verbind aan ‘n omset in plantgemeenskappe (beide spesie en filogenetiese) by beide plaaslik en vir die hele streek. Hierdie dui op insekgasheerspesifisiteit. Plantgemeenskappe wys omset teen kort ruimtelike skale (0.1-3 km). Insekte wys ‘n soortgelyke patron, maar die afname in oorvleueling tussen gemeenskappe is meer geredelik. Dit dui dat insek meer as een gasheer kan gebruik, terwyl plante streng tot sekere nisse verbind is. Die ontluikende struktuur van menigde interaksienetwerke wys geen ruimtelike of tydelike variasie nie, ten spyte van hoë gemeenskapsomset. Nietewel, die interne struktuur van die netwerke wys veranderinge (interaksies in netwerke wys omset). Seisonale interaksie-omset kan toegeskryf word aan ‘n omset van herbivore en insekgasheerverandering. Ruimtelike interaksie-omset word toegeskryf aan gelyktydige insek- en plantomset, wat óf deur insekgasheerspesifisiteit veroorsaak word óf deur parallele reaksies tot omgewingsveranderinge. Ruimtelike interaksie-omset word ook deur plantomset beïnvloed, wat aandui sommige insekte kan meer as een gasheer benut en insekte het weier verspreidings as hul gasheer. Resultate dui daarop dat insekgasheerspesifisiteit, maar waarskynlik nie op die spesievlak nie, moontlik die primêre meganisme is wat insekgemeenskappe verbind aan die Restionaceae in die KBR struktureer.

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