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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.
61

The incremental cost approach and the conservation of biological diversity basis for lasting partnerships of the global commons? /

Labbate, Gabriel David. January 2000 (has links)
Thesis (Ph. D.)--University of California, Santa Cruz, 2000. / Typescript. Includes bibliographical references.
62

Marine benthic biodiversity-ecosystem function relations in complex systems

Godbold, Jasmin Annica. January 2008 (has links)
Thesis (Ph.D.)--Aberdeen University, 2008. / "Oceanlab" Includes bibliographical references.
63

Small mammal biodiversity in Nepal

Pearch, Malcolm J. January 2009 (has links)
Thesis (M.Phil)--Aberdeen University, 2009. / Title from web page (viewed on July 28, 2009). Includes bibliographical references.
64

Isolamento e identificação de actinobacterias em solos de terra preta antropogenica (TPA) da Amazonia Central por ARDRA e sequenciamento do gene 16S rRNA / Isolation and identification of actinobacteria in anthropogenic dark earth of Central Amazon by ARDRA and seguencing of 16S rRNA gene

Garcia, Carlos Eduardo 21 February 2006 (has links)
Orientadores: Fumio Yokota, Tasi Siu Mui / Tese (doutorado) - Universidade Estadual de Campinas, Faculdade de Engenharia de Alimentos / Made available in DSpace on 2018-08-05T16:40:59Z (GMT). No. of bitstreams: 1 Garcia_CarlosEduardo_D.pdf: 3424911 bytes, checksum: 6338d2ede1846761521ec0cfb4c5e1ec (MD5) Previous issue date: 2006 / Doutorado / Doutor em Ciência de Alimentos
65

Adequacy of existing protected areas in conserving biodiversity at global and regional levels in relation to socio-economic conditions

Gaika, Lindiwe January 2005 (has links)
Magister Scientiae - MSc (Biodiversity and Conservation Biology) / At a meeting of worl leaders at the United Nations Conference on Environment and Development in Rio de Janeiro in 1992, it was recognized that because of the tremendous increase in the size of the global populations (which now is estimated to exceed six billion), there were concerns that global biodiversity was at risk if insufficient land were not put aside for conservation within formal Protected Areas. The primary aim of this study was to compare investment in Protected Areas in relation to socio-economic conditions at global and regional levels. / South Africa
66

A multicriteria assessment of regional sustainability options in the Northern Province, South Africa

Reyers, Belinda 29 May 2006 (has links)
Please read the abstract in the section, 00front, of this document / Thesis (DPhil (Zoology))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted
67

The effects of natural and anthropogenic disturbances on the structure and composition of early-successional plant communities in the Interior Cedar-Hemlock (ICH) zone of southern British Columbia

Corriveau, Brit Madelaine 11 1900 (has links)
Wildfire is the primary natural disturbance in Interior Cedar-Hemlock (ICH) forests, and since the mid-20th century, forest harvesting (clearcutting, in this case) has become the primary anthropogenic disturbance type. Forest management in British Columbia is currently governed by a paradigm that maintains that biological diversity can be preserved by utilizing forest harvesting regimes that closely mimic "natural" disturbance regimes, but a question remains as to how closely these regimes mimic wildfire disturbances. More specifically, how do clearcutting and wildfires compare in their effects on the structure and composition of early-successional ICH plant communities? This study compares vegetation structure, composition, relative abundance and diversity among 39 sites that experienced either a stand-replacing fire or a clearcut within the last 40 years. Sites of different ages and disturbance types were located within the wet cool ICHwkl and very-wet cool ICHvk I biogeoclimatic variants near Revelstoke, B.C. For each site, overstory structural characteristics (tree and snag diameters, basal area and density), overstory composition, and surface fuels (volume of coarse woody debris (CWD)) were assessed. Understory vegetation percent cover, species richness, composition and diversity were also determined. Linear regression analysis was used to examine differences in each of these variables between disturbance types, over time. The trends in structural legacies (especially snag and CWD dynamics) varied greatly between wildfire and clearcut sites. Compared to burned sites, clearcut sites exhibited patterns of accelerated succession in several characteristics (overstory tree regeneration, vegetation cover and understory species richness) due to planting treatments and pre-disturbance relicts. Understory species composition also varied between disturbances, with clearcut sites containing more shade-tolerant survivors initially. Both disturbance types had similar levels of floristic diversity during early succession. These results suggest that clearcut harvesting may not emulate stand-replacing fires in terms of impact on early ICH plant succession in any aspect but diversity. However, it is unclear if these early-successional differences will continue through time. There is a need for further research in this ecosystem, as well as any other ecosystems where emulation silviculture is applied, in order to confirm that silvicultural effects mimic those of natural disturbance regimes. / Forestry, Faculty of / Graduate
68

A co-evolutionary landscape ecology framework for analyzing human effects on KwaZulu-Natal Province landscapes and its relevance to sustainable biodiversity conservation

Fairbanks, Dean Howard Kenneth 13 July 2006 (has links)
The conservation of biotic diversity is a growing challenge within southern Africa at the beginning of the 21st century. Growing populations and trends toward a questionable Western development model place demands on the use of land for food, fiber, and fuel production. The traditional establishment and use of formal conservation areas is being challenged against the needs of humans and the past unbalances created by colonial rule. Conservation areas, as isolated islands in a sea of change driven by interconnected economic and social systems, may not be a basis for sustainable biodiversity conservation. This thesis examines characteristics of avian species diversity response to abiotic environmental variables and land transformation. Environmental and land-use correlates of species gradients, species diversity patterns, and the spatial patterning of bird assemblages varied with location. The findings supported a conceptual model of multi-scaled controls on bird distribution, and the related notion that local community structure is the result of both regional environmental and local-scale landscape pattern that must be taken in to account in regional conservation planning assessments. An analytical framework including an landscape model, use of complementary-based reserve selection procedures, gradient analysis, and inclusion of the total spatial economy and development needs of the KwaZulu-Natal Province proved to be important for developing an integrated conservation plan for sustainable avian conservation. Pattern recognition results of the spatial economy and landscape pattern revealed the strong dichotomy in Western economic versus rural African landscapes, which have lead to strong differences in avian assemblage patterns. The research described in this thesis targets specific objectives of the Sustainable Biosphere Initiative by addressing requirements for landscape level analysis of humans and ecosystems in an integrated analytical framework. The development of a co-evolutionary landscape ecology framework for examining human-ecosystem interaction provides a strong basis for supporting targeted conservation planning within regions rather than supporting a generic conservation planning framework. / Thesis (DPhil (Sustainable Ecological Management))--University of Pretoria, 2007. / Zoology and Entomology / unrestricted
69

Biodiversity and climate change : a South African perspective

Erasmus, Barend Frederik Nel 09 May 2005 (has links)
The responsiveness of South African fauna to climate change events is poorly documented and not routinely incorporated into regional conservation planning exercises. The lack of detailed distribution data for appreciable numbers of taxa demands a modeling solution. We develop a climate envelope model to predict potential distribution range changes. The model can be used to interpolate the distributions of poorly sampled taxa as well as predict responses to a changing climate. It is predicted that species from the more arid western parts of South Africa will be subject to severe range contraction and range shifts whereas the species from the more mesic eastern parts will experience range contraction with limited range shift. Species that could act as climate change indicator taxa are identified based on their predicted extreme range change responses to climate change. Red-data and vulnerable species were more likely to display range change than less threatened species. Without mitigatory action, conservation areas are likely to lose species. The likelihood of successful range shifts will be affected by the nature of novel communities, habitat suitability and the degree of land transformation encountered. Given the extent of the predicted spatial responses, conservation planners can no longer afford to ignore future climate impacts on species distribution patterns. Disease risk profiles are also expected to change with climate; currently, susceptible forestry plantations exist in areas which may be invaded by an economically important pathogen. Resistant clones should be planted in these future high-risk areas. A decrease in precipitation is an important feature of a future climate. This decrease is expected to impact on the agricultural sector by reducing total employment as producers switch to a more extensive production pattern. The total decline in welfare, therefore, will fall disproportionately on the poor. Climate change presents a significant treat to the South African biodiversity estate, and our ability to manage this transition in the face of changing and competing land uses. Adaptation and mitigation options do exist but they are hampered by a lack of definitive analyses, and ultimately, political will to prioritise the threat of climate change. / Thesis (PhD(Zoology))--University of Pretoria, 2006. / Zoology and Entomology / unrestricted
70

Biologinės įvairovės konvencijos įgyvendinimo Lietuvoje analizė ir vertinimas / Analysis and evaluation of the implementation of the Convention on Biological Diversity in Lithuania

Meilūnė, Jolita 25 June 2013 (has links)
Magistro baigiamajame darbe išanalizuotas ir įvertintas Biologinės įvairovės konvencijos įgyvendinimas Lietuvoje, iškeltos Biologinės įvairovės konvencijos įgyvendinimo Lietuvoje problemos bei pateikti siūlymai, kaip pagerinti Biologinės įvairovės konvencijos įgyvendinimą Lietuvoje. Pirmoje darbo dalyje analizuojami LR ratifikuotų konvencijų, susijusių su biologinės įvairovės apsauga, priėmimo ir įgyvendinimo principai bei pagrindiniai bruožai. Antroje dalyje nagrinėjami Biologinės įvairovės konvencijos tikslų įgyvendinimo ypatumai pasaulyje ir Europos Sąjungoje. Trečioje dalyje pateikiama Biologinės įvairovės konvencijos įgyvendinimo Lietuvoje analizė ir vertinimas. / In this Master thesis, the implementation of the Convention on Biological Diversity in Lithuania has been analysed and evaluated, problems of the implementation of the Convention on Biological Diversity in Lithuania have been raised and suggestions how to improve the implementation of the Convention on Biological Diversity in Lithuania have been presented. In the first part of the thesis, the principles of adoption and implementation and the main features of the conventions related to the protection of biodiversity and ratified by the Republic of Lithuania have been analysed. In the second part of it, the implementation peculiarities of the objectives of the Convention on Biological Diversity in the world and in the European Union have been investigated. In the third part, the analysis and evaluation of the implementation of the Convention on Biological Diversity in Lithuania have been presented.

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