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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.
281

Tree holes as habitat for aquatic and terrestrial invertebrates in mixed broadleaf-podocarp rainforest, New Zealand

Blakely, Tanya Jillaine January 2008 (has links)
Little is known about the spatial distribution and abundance of tree holes in New Zealand’s native forests, or the invertebrate communities that they support. I found that tree holes were common on five endemic tree species, belonging to the families Fagaceae and Podocarpaceae in the mixed broadleaf-podocarp rainforest of Orikaka Ecological Area, Buller District, New Zealand. However, tree holes were not uniformly distributed throughout the forest, with more holes found on the three podocarp species, Prumnopitys ferruginea, P. taxifolia and Dacrycarpus dacrydioides, than on Nothofagus fusca or N. menziesii. Nevertheless, Nothofagus fusca had the largest holes of any of the tree species sampled and larger trees generally had larger holes. Large, hole-bearing Nothofagus fusca trees support a specialist hole-dwelling vertebrate fauna in New Zealand and worldwide, tree holes provide habitat for a range of invertebrate species. Using specially-designed emergence traps, I collected invertebrates emerging from naturally-occurring dry tree holes and compared this assemblage with invertebrates inhabiting leaf litter on the forest floor and those dispersing aerially throughout the study area. At the higher taxonomic resolution (i.e., Order or Class), community composition within the tree holes was highly variable, and there was no strong distinction between invertebrates from tree holes, leaf litter or Malaise traps. Moreover, although some beetle species emerging from tree holes were found exclusively in tree holes, most of these were represented by a single individual. Consequently, only minor differences in species composition were detected between beetle assemblages from tree holes, leaf-litter and those aerially dispersing throughout the forest. In contrast, the aquatic invertebrate assemblage within water-filled tree holes was highly distinctive from that in ground-based freshwater ecosystems, with only six aquatic taxa in common between all freshwater habitats. Using experimental water-filled tree-hole microcosms, I found that species richness and community composition within these microcosms were primarily driven by resource concentration, although habitat quality (i.e., water chemistry parameters) was also an important determinant of the identity and composition of colonising species. Overall, my study has shown that tree holes are common in the study area, and are likely to be more abundant in New Zealand’s indigenous forests than previously thought. Moreover, these generally small, discrete forest ecosystems support a diverse array of terrestrial invertebrates as well as a distinctive aquatic invertebrate community that is primarily structured by organic matter resource availability. These findings not only represent an important advance in our knowledge of New Zealand’s freshwater invertebrate biodiversity, but also highlight the need for further investigation into these unique forest canopy habitats which may well be at risk from deforestation and land use change.
282

Neutrino oscillations and the early universe /

Bell, Nicole F. January 2000 (has links)
Thesis (Ph.D.)--University of Melbourne, School of Physics, 2001. / Typescript (photocopy). Includes bibliographical references (leaves 124-135).
283

Simulating ultracold matter : horizons and slow light /

Farrell, Conor. January 2008 (has links)
Thesis (Ph.D.) - University of St Andrews, January 2008.
284

Dye sensitized n-p heterojunctions of titanium dioxide and copper thiocyanate, a new interface for photoinduced charge separation /

O'Regan, Brian C. January 1998 (has links)
Thesis (Ph. D.)--University of Washington, 1998. / Vita. Includes bibliographical references (leaves [108]-114).
285

Some effects of spacetime curvature in general relativity /

McClune, James C. January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
286

Some effects of spacetime curvature in general relativity

McClune, James C. January 1997 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 1997. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
287

Computational and astrophysical studies of black hole spacetimes

Bonning, Erin Wells, Matzner, Richard A. January 2004 (has links) (PDF)
Thesis (Ph. D.)--University of Texas at Austin, 2004. / Supervisor: Richard Matzner. Vita. Includes bibliographical references. Available also from UMI company.
288

Initial data for black holes and rough spacetimes /

Maxwell, David A. January 2004 (has links)
Thesis (Ph. D.)--University of Washington, 2004. / Vita. Includes bibliographical references (p. 90-94).
289

Applied mathematics of space-time & space+time : problems in general relativity and cosmology : a thesis submitted to the Victoria University of Wellington in fulfilment of the requirements for the degree of Doctor of Philosophy in Mathematics /

Cattoën, Céline. January 2009 (has links)
Thesis (Ph.D.)--Victoria University of Wellington, 2009. / Includes bibliographical references.
290

Fuzzy blackholes

Murugan, Anand 01 May 2007 (has links)
The fuzzball model of a black hole is an attempt to resolve the many paradoxes and puzzles of black hole physics that have revealed themselves over the last century. These badly behaved solutions of general relativity have given physicists one of the few laboratories to test candidate quantum theories of gravity. Though little is known about exactly what lies beyond the event horizon, and what the ultimate fate of matter that falls in to a black hole is, we know a few intriguing and elegant semi-classical results that have kept physicists occupied. Among these are the known black hole entropy and the Hawking radiation process.

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