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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

Assessing biodiversity intactness

Biggs, Reinette 06 August 2008 (has links)
No description available.
2

Diversity, Phylogeography, and Taxonomy of Hard-Corals in the Genus Porites from the Arabian Peninsula

Terraneo, Tullia Isotta 12 1900 (has links)
The genus Porites is one of the most important scleractinian genera in terms of species diversity and panmictic tropical distribution. However, Porites is notorious for challenging taxonomic identification based on colony gross morphology, micromorphology, and single gene analyses, suggesting that the current classification poorly represents real evolutionary relationships. This research integrates skeletal morphology data and single locus genetic evidence with genome-wide analyses and alternative line of evidence to taxonomy (i.e. symbiotic association data), with the aim of clarifying biodiversity, biogeography, and taxonomy of Porites from the Arabian Peninsula. In this dissertation, I evaluated the diversity of Porites in the Red Sea and the Gulf of Aden, providing a basic morpho-molecular background to the taxonomy of Porites in the region, and highlighting that a) the current taxonomic and phylogenetic position of 15 Porites morphological species needs to be reassessed, and that b) coral biodiversity in the Arabian region needs to be re-evaluated. To address this, I reconstructed the complete mitochondrial genomes of two endemic Red Sea species, contributing a solid framework for clarifying the phylogeny and taxonomy of Porites in future molecular studies. I implemented the morpho-molecular results with high-throughput sequencing data, generating a comprehensive hypothesis of species boundaries and biogeography of Porites in the seas surrounding the Arabian Peninsula. These results suggested that 15 morphological species from this region, were clustered into eight molecular lineages, two of which previously unknown. Finally, using the nuclear Internal Transcribed Spacer II (ITS2) marker in a high-throughput sequencing framework, I presented evidence derived from symbiotic association of Porites with dinoflagellates in the family Symbiodiniaceae. Symbiont diversity showed patterns of geographic-specific association at multiple levels, including at the level of Symbiodiniaceae genera, majority ITS2 sequences, and ITS2 type profile levels. Specific associations with host genotypes were also recovered, providing a further line of evidence that the current taxonomy of Porites is in need for revision. This dissertation highlights the utility of an integrated approach to taxonomy in elucidating species boundaries and phylogenetic relationships in Scleractinia and represents a framework that could be applied to other taxa awaiting revision.
3

The role of local government in the conservation of biodiversity

Kelly, Andrew H. H. January 2006 (has links)
Thesis (Ph.D.) -- University of Wollongong, 2004. / Includes bibliographical references.
4

Die Sanierung von Biodiversitätsschäden nach der europäischen Umwelthaftungsrichtlinie

Kiess, Carolin. January 2008 (has links)
Thesis (doctoral)--Universität Mannheim, 2007. / Description based on print version record. Includes bibliographical references (p. [219]-230) and subject index.
5

The effects of increasing atmospheric nitrogen deposition and carbon dioxide on the growth and physiology of component species of the chalk grassland plant community

Bryant, Jonathan January 1998 (has links)
No description available.
6

Ecology and socio-economic importance of short fallows in the humid forest zone of Southern Cameroon

Ngobo Nkongo, Martine P. January 2002 (has links)
No description available.
7

Právní problematika ochrany biodiverzity / Legal issues of the protection of biodiversity

Zicha, Jiří January 2010 (has links)
Legal problems of biodiversity conservation, dissertation JUDr. Ji í Zicha, supervisor: prof. JUDr. Milan Damohorský, DrSc. Charles University, Faculty of Law, Department of Environemntal Law Prague, September 2010 The aim of the dissertation is to confront legal and institutional framework of conservation of biodiversity with its biological principles and most serious current threats, and assess to which extend are these systems and phenomenons in conformity and where eventually exist gaps and shortages. As a method of this confrontation was chosen an overview and analysis of relevant sources of law and other related information in the context of each level of biodiversity, and further in the context of several substantive and legal connections. With respect to characteristics of biodiversity which, similarly as other components of environment, does not respect borders created artificially by man, international law of global and regional scope plays a crucial role. It is valid almost without any reservation for nearly homogenous marine environment, in case of terrestrial environment some physical and geographical framgmentation can be observed and the role of particular state with its internal legal regime is more important. Individual issues are therefore primarily discussed from the point of...
8

A multifaceted appraisal of a large-scale, multi-taxon biodiversity monitoring initiative

Haughland, Diane L Unknown Date
No description available.
9

Investing in biological diversity : economic valuation and priorities for development

Moran, Dominic January 1997 (has links)
By all informed scientific accounts the world's biological diversity is currently in a critical condition. Biodiversity is vital for the continued existence of the global biosphere and, by extension, human wellbeing and development. It is inconceivable that a discipline predicated on the issues of scarcity and choice has nothing to contribute in terms of an understanding of either the causes and consequences of biodiversity loss, or in proposing solutions to the crisis. This thesis examines some of the economic parameters of the issue. Alongside the acknowledged root problems of market and institutional failure lies the question of economic valuation. Valuation of biodiversity puts conservation on a more level playing field with the economic forces which threaten its demise. Provided economic values can be appropriated (i.e. converted to flows of real economic resources) it becomes worthwhile for countries to invest in valuable biological assets. But the practice of economic valuation and the quantification of biodiversity are in their infancy and the complexity of the latter hinders the precise application of the former. Much of this thesis focuses on the use and development of the contingent valuation method (CV) as a flexible approach to valuing biodiversity. The method has a useful role to play in resource allocation, and, for valuing biological resources. Faced by the irreducible complexity of life which is the essence of biodiversity, CV does have its limitations. It is possible to conclude that existing valuation methods are a vital part of a "holding operation" alongside other surrogate approaches to setting priorities for global conservation. Nevertheless, the development of an interface between economic (preference-based) values, and biological values, which together can comprehensively inform conservation decisions remains the objective for the future.
10

Biodiversity over the edge : civil society and the protection of transborder regions in northern America /

Chester, Charles C. January 2002 (has links)
Submitted to the Fletcher School of Law and Diplomacy. Thesis (Ph.D.)--Tufts University, 2002. / Adviser: William R. Moomaw. Includes bibliographical references. Access restricted to members of the Tufts University community. Also available via the World Wide Web;

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