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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.
131

Origins of diversity : the evolutionary genetics of Caribbean butterflies

Davies, Neil January 1995 (has links)
No description available.
132

Comparative biological and taxonomic studies of tropical and temperate Laboulbeniales (fungi; Ascomycota)

Weir, Alexander January 1997 (has links)
No description available.
133

The precautionary principle and marine nature conservation

Sifakis, Antonios January 2001 (has links)
No description available.
134

The taxonomic and ecological aspects of the Thelotremataceae in southeast Asia

Homchantara, Natsurang January 1999 (has links)
No description available.
135

The diversity of Coleoptera assemblages in different habitat types in Sabah, Malaysia, with special reference to herbivory

Chung, Arthur Y. C. January 1999 (has links)
No description available.
136

Increasing impacts of land use on biodiversity and carbon sequestration driven by population and economic growth

Marques, Alexandra, Martins, Ines, Kastner, Thomas, Plutzar, Christoph, Theurl, Michaela, Eisenmenger, Nina, Huijbregts, Mark, Wood, Richard, Stadler, Konstantin, Bruckner, Martin, Canelas, Joana, Hilbers, Jelle, Tukker, Arnold, Erb, Karlheinz, Pereira, Henrique January 2019 (has links) (PDF)
Biodiversity and ecosystem service losses driven by land-use change are expected to intensify as a growing and more affluent global population requires more agricultural and forestry products, and teleconnections in the global economy lead to increasing remote environmental responsibility. By combining global biophysical and economic models, we show that, between the years 2000 and 2011, overall population and economic growth resulted in increasing total impacts on bird diversity and carbon sequestration globally, despite a reduction of land-use impacts per unit of gross domestic product (GDP). The exceptions were North America and Western Europe, where there was a reduction of forestry and agriculture impacts on nature accentuated by the 2007-2008 financial crisis. Biodiversity losses occurred predominantly in Central and Southern America, Africa and Asia with international trade an important and growing driver. In 2011, 33% of Central and Southern America and 26% of Africa's biodiversity impacts were driven by consumption in other world regions. Overall, cattle farming is the major driver of biodiversity loss, but oil seed production showed the largest increases in biodiversity impacts. Forestry activities exerted the highest impact on carbon sequestration, and also showed the largest increase in the 2000-2011 period. Our results suggest that to address the biodiversity crisis, governments should take an equitable approach recognizing remote responsibility, and promote a shift of economic development towards activities with low biodiversity impacts.
137

Tetrapod biodiversity through the Permo-Triassic Beaufort Group (Karoo Supergroup) of South Africa

Nicolas, Merrill Victoria Mary 15 August 2008 (has links)
A B S T R A C T The rocks of the Beaufort Group of South Africa record a remarkably complete depositional sequence incorporating a rich fossil tetrapod succession from the mid-Permian to mid-Triassic. This represents one of the best preserved ecological assemblages of pre-mammalian terrestrial tetrapods documenting the stem lineages of both mammals and dinosaurs. For more than a century large collections of fossils from the Beaufort Group have been built up at various museums in South Africa. With the co-operation of all the South African museums curating collections of Karoo fossils, a single standardised database has been compiled for the fossils collected from the Beaufort Group as well as a GIS system incorporating all the South African databases of fossil records. Major problems which had to be overcome related largely to the non-standardised nature of different databases, locality, and taxonomic information. Particularly problematic was entering ambiguous and vague locality information onto the GIS database, so that it would still be useful for qualitative evaluation. The created GIS database is a useful analytical tool, but requires streamlining to make it accessible to all users. Completion of the foundation phase of the GIS database has highlighted problems which need to be addressed in the future to make the database an effective tool for research purposes.
138

Microbial Biodiversity of the Atmosphere

Klein, Ann 23 February 2016 (has links)
Microorganisms are critical to the functioning of terrestrial and aquatic ecosystems and may also play a role in the functioning of the atmosphere. However, little is known about the diversity and function of microorganisms in the atmosphere. To investigate the forces driving the assembly of bacterial microbial communities in the atmosphere, I measured temporal variation in bacterial diversity and composition over diurnal and inter-day time scales. Results suggest that bacterial communities in the atmosphere markedly vary over diurnal time scales and are likely structured by inputs from both local terrestrial and long-distance sources. To assess the potential functions of bacteria and fungi in the atmosphere, I characterized total and potentially active communities using both RNA- and DNA-based data. Results suggest there are metabolically active microorganisms in the atmosphere that may affect atmospheric functions including precipitation development and carbon cycling. This dissertation includes previously published and unpublished co-authored material.
139

Identification of species limits : clarifying taxonomy and ecology of BAP lichens

Bogomazova, Kristine January 2018 (has links)
No description available.
140

Effects of Dietary Mercury Exposure on Spatial Memory of Zebra Finches, Taeniopygia guttata

Bessler, Amanda Mae 01 January 2011 (has links)
No description available.

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