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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

Assortative mating as a barrier to gene flow in a coral reef fish species flock /

Barreto, Felipe S. January 2003 (has links) (PDF)
Thesis (M.S.)--University of North Carolina at Wilmington, 2003. / Includes bibliographical references (leaves : 46-50).
132

Coral propagation for aquarium specimens.

Jordan, Ingrid Elizabeth. January 2001 (has links)
Coral reefs are being destroyed and degraded by natural and anthropogenic processes. Live corals are becoming increasingly popular as marine aquarium specimens, in both the commercial and private sectors, leading to the degradation of coral reefs. This often has serious economic implications for the fishing, aquarium and tourist industries. It is clear that there is a need for the management and protection of these fragile ecosystems. The artificial propagation of coral is desirable as it will alleviate the demand for wild coral specimens, and will also provide a stock for the rehabilitation of damaged reefs. Although corals are being propagated worldwide by hobbyists, reports on their work are mainly anecdotal and there is little in the scientific literature on the specific requirements for optimal growth rates and survival in suitable coral species. This study thus focused on developing techniques to propagate a range of appropriate coral species and to promote their optimal growth. The results revealed that different morphological groups of scleractinian corals require specialised techniques of fragmentation and attachment to ensure survival. The corals were broken using a hammer and chisel. Attachment techniques varied from the use of superglue (which is widely used in the United States), to thermoplastic glue. The mean mortality using superglue was 73% (n=120, ±0.167), using epoxy, 62% (n=120, ±0.127) and with thermoplastic glue it was 11% (n=120, ±0.108) Superglue was extremely difficult to work with and proved ineffective, especially when attempting to glue uneven surfaces. Certain species did not survive using this adhesive due to exposure of the coral to air. The most effective method of rapid attachment was the use of thermoplastic glue that set rapidly underwater. The use of electrolysis to promote the attachment of coral nubbins was tested as an alternative to the various adhesives. This method increased the survival of the nubbins and eliminated exposure to air. It has proven suitable for both coral propagation and in situ reef rehabilitation. Growth experiments revealed that the manipulation of current flow, light and the addition of different feeds had different effects on the growth rates of selected candidate species. A suite of optima was thus developed for each species. The majority of species grew best in a bi-directional current flow, with yeast as feed, under actinic blue light. An experiment that combined the optimal current flow, feed and light conditions, revealed that the majority of species grew best under mixed light with yeast as feed. The trade in corals is sensitive in terms of their handling, transportation and CITES (Convention on International Trade in Endangered Species) status. Having established the viability of their propagation, consideration was given to appropriate regulatory and marketing procedures to accommodate this sensitivity of the cultivated material. / Thesis (M.Sc.)-University of Natal, Durban, 2001.
133

Reproduction and recruitment of scleractinian corals on equatorial reefs in Mombasa, Kenya

Mangubhai, Sangeeta Unknown Date (has links)
This study examined patterns of coral reproduction and recruitment on lagoonal reefs adjacent to Mombasa in Kenya, at latitude 4ºS. Very little detailed research has been done on the reproductive patterns of scleractinian corals on equatorial reefs, where it has been suggested that seasonality and spawning synchrony may break down due to the weak environmental cues that are thought to govern the onset and timing of reproduction. Gametogenic data were collected for three faviid (Echinopora gemmacea, Platygyra daedalea and Leptoria phrygia) and three Acropora species (A. tenuis, A. valida and Acropora sp.1) in the Mombasa Marine National Park and Reserve between April 2003 – May 2005. A further 20 species of Acropora were identified (9 species represented range extensions) and marked to examine intra- and inter-specific spawning synchrony within this genus. In comparison to other regions, the overall pattern of coral reproduction in Kenya was found to be asynchronous, with spawning occurring over 9 months of the year from August – April, with some level of ‘temporal reproductive isolation’ occurring between species in relation to the main lunar month and lunar quarter when spawning occurred. Proximate cues governing the timing of reproduction could not be clearly discerned in Kenya with spawning occurring during both rising and maximum temperatures, during both neap and spring tides and across all lunar phases. Acropora species spawned over a 7-month period between October – April and faviid species over a 5-month period from December - April. The timing of reproduction in Acropora varied both within and among species, with the main release of gametes occurring from January – March when sea surface temperatures were at their summer maximum. Individual species released gametes over 2-5 months. The greatest overlap in spawning Acropora species occurred in February, which coincided with the spawning months of P. daedalea and E. gemmacea and suggests that some degree of multispecific spawning is a characteristic of Kenyan reefs. Within the main spawning period individual Acropora species had their main spawning in different lunar months. Acropora species released gametes in all lunar quarters, with the highest number of colonies and species spawning in the 3rd lunar quarter (i.e. in the 7 nights after full moon). Spawning in the faviids was more synchronised than Acropora species with the majority of faviid corals spawning in the 3rd lunar quarter. Single annual cycles of gametogenesis were recorded in E. gemmacea, A. tenuis, L.phrygia, most colonies of A. valida and Acropora sp.1, and in 84% of P. daedalea colonies. Biannual cycles of gametogenesis were recorded in 16% of P.daedalea colonies, which included two morphotypes identified in the Mombasa lagoon through morphometric and genetic studies. The presence of different oocyte sizes in L.phrygia during gametogenesis suggested that in some colonies there were two slightly overlapping oogenic cycles, which terminated in spawning within 1-2 months of each other. Overlapping oogenic cycles have not previously been recorded in hermaphroditic broadcast spawning corals in the tropics. The findings from Kenya support the hypothesis of protracted breeding seasons and a breakdown of spawning synchrony nearer the equator. It is hypothesised that the high fecundities recorded in faviid and Acropora species in Kenya compared to other regions, may allow reef corals to stagger their reproduction over 2-5 months, without incurring a significant reduction in fertilisation rates. Spat from the Family Pocilloporidae dominated settlement tiles in the Marine National Park and Reserve comprising 93.7% of spat, which contrasts with other tropical reefs where Acroporidae spat dominate. Patterns of settlement of Acroporidae spat generally coincided with the timing and extended spawning season in Acropora species in Kenya. The density and relative composition of coral recruits and juvenile corals on natural substrata recorded during this study were similar to those recorded before the 1997-98 bleaching event. There is no evidence to suggest that Kenya’s reefs have undergone a phase-shift in community structure, and reef recovery is occurring post-bleaching with mean percent hard coral cover currently at 25%. The slow rate of recovery of Kenya’s reefs is likely to reflect the scale of the mortality, source and availability of coral larvae as well as post-settlement processes operating at individual sites. In the medium-term, the recovery of Kenya’s reefs appears to be more strongly dependent on larvae from local reefs.
134

Reproduction and recruitment of scleractinian corals on equatorial reefs in Mombasa, Kenya

Mangubhai, Sangeeta Unknown Date (has links)
This study examined patterns of coral reproduction and recruitment on lagoonal reefs adjacent to Mombasa in Kenya, at latitude 4ºS. Very little detailed research has been done on the reproductive patterns of scleractinian corals on equatorial reefs, where it has been suggested that seasonality and spawning synchrony may break down due to the weak environmental cues that are thought to govern the onset and timing of reproduction. Gametogenic data were collected for three faviid (Echinopora gemmacea, Platygyra daedalea and Leptoria phrygia) and three Acropora species (A. tenuis, A. valida and Acropora sp.1) in the Mombasa Marine National Park and Reserve between April 2003 – May 2005. A further 20 species of Acropora were identified (9 species represented range extensions) and marked to examine intra- and inter-specific spawning synchrony within this genus. In comparison to other regions, the overall pattern of coral reproduction in Kenya was found to be asynchronous, with spawning occurring over 9 months of the year from August – April, with some level of ‘temporal reproductive isolation’ occurring between species in relation to the main lunar month and lunar quarter when spawning occurred. Proximate cues governing the timing of reproduction could not be clearly discerned in Kenya with spawning occurring during both rising and maximum temperatures, during both neap and spring tides and across all lunar phases. Acropora species spawned over a 7-month period between October – April and faviid species over a 5-month period from December - April. The timing of reproduction in Acropora varied both within and among species, with the main release of gametes occurring from January – March when sea surface temperatures were at their summer maximum. Individual species released gametes over 2-5 months. The greatest overlap in spawning Acropora species occurred in February, which coincided with the spawning months of P. daedalea and E. gemmacea and suggests that some degree of multispecific spawning is a characteristic of Kenyan reefs. Within the main spawning period individual Acropora species had their main spawning in different lunar months. Acropora species released gametes in all lunar quarters, with the highest number of colonies and species spawning in the 3rd lunar quarter (i.e. in the 7 nights after full moon). Spawning in the faviids was more synchronised than Acropora species with the majority of faviid corals spawning in the 3rd lunar quarter. Single annual cycles of gametogenesis were recorded in E. gemmacea, A. tenuis, L.phrygia, most colonies of A. valida and Acropora sp.1, and in 84% of P. daedalea colonies. Biannual cycles of gametogenesis were recorded in 16% of P.daedalea colonies, which included two morphotypes identified in the Mombasa lagoon through morphometric and genetic studies. The presence of different oocyte sizes in L.phrygia during gametogenesis suggested that in some colonies there were two slightly overlapping oogenic cycles, which terminated in spawning within 1-2 months of each other. Overlapping oogenic cycles have not previously been recorded in hermaphroditic broadcast spawning corals in the tropics. The findings from Kenya support the hypothesis of protracted breeding seasons and a breakdown of spawning synchrony nearer the equator. It is hypothesised that the high fecundities recorded in faviid and Acropora species in Kenya compared to other regions, may allow reef corals to stagger their reproduction over 2-5 months, without incurring a significant reduction in fertilisation rates. Spat from the Family Pocilloporidae dominated settlement tiles in the Marine National Park and Reserve comprising 93.7% of spat, which contrasts with other tropical reefs where Acroporidae spat dominate. Patterns of settlement of Acroporidae spat generally coincided with the timing and extended spawning season in Acropora species in Kenya. The density and relative composition of coral recruits and juvenile corals on natural substrata recorded during this study were similar to those recorded before the 1997-98 bleaching event. There is no evidence to suggest that Kenya’s reefs have undergone a phase-shift in community structure, and reef recovery is occurring post-bleaching with mean percent hard coral cover currently at 25%. The slow rate of recovery of Kenya’s reefs is likely to reflect the scale of the mortality, source and availability of coral larvae as well as post-settlement processes operating at individual sites. In the medium-term, the recovery of Kenya’s reefs appears to be more strongly dependent on larvae from local reefs.
135

Parental and environmental effects on the early life history of a tropical reef fish, Amphiprion melanopus /

Green, Bridget Siobhan. January 2004 (has links)
Thesis (Ph.D.) - James Cook University, 2004. / Typescript (photocopy) Bibliography: leaves 105-116.
136

Derivation of near-shore bathymetry from multispectral satellite imagery used in a coastal terrain model for the topographic analysis of human influence on coral reefs /

Hogrefe, Kyle Richard. January 1900 (has links)
Thesis (M.S.)--Oregon State University, 2009. / Printout. Includes bibliographical references. Also available on the World Wide Web.
137

Socio-economic and ecological impacts of coral reef management in Indonesia

Afifi, Mansur. January 2003 (has links)
Thesis (doctoral)--Universität, Bochum, 2003. / Includes bibliographical references (p. 215-227).
138

O ensaio coral sob a perspectiva da performance musical

Prueter, Priscilla Battini 28 January 2013 (has links)
Resumo: A presente dissertação discute, sob o ponto de vista da performance musical, abordagens metodológicas e aplicações técnicas que contribuem, de maneira efetiva, para uma construção da performance durante o ensaio coral. Discorre sobre o processo interpretativo dentro da prática coral e a função de intérprete que regente e coralista exercem simultaneamente ao executar uma obra musical. Aborda aspectos que devem ser considerados para a escolha adequada do repertório do grupo. Também traz questionamentos sobre a função da técnica vocal durante o ensaio, assim como, a técnica vocal do próprio regente coral. A dissertação contorna o planejamento de ensaios, organização de conteúdos e aplicação de técnicas e estratégias que possam oferecer ao regente um melhor aproveitamento do tempo de ensaio com o intuito de melhorar a performance do coro.
139

Quorum Sensing and Microbial Interactions in Coral Black Band Disease and Coral-Associated Bacteria

Zimmer, Beth L 08 November 2012 (has links)
The black band disease (BBD) microbial consortium often causes mortality of reef-building corals. Microbial chemical interactions (i.e., quorum sensing (QS) and antimicrobial production) may be involved in the BBD disease process. Culture filtrates (CFs) from over 150 bacterial isolates from BBD and the surface mucopolysaccharide layer (SML) of healthy and diseased corals were screened for acyl homoserine lactone (AHL) and Autoinducer-2 (AI-2) QS signals using bacterial reporter strains. AHLs were detected in all BBD mat samples and nine CFs. More than half of the CFs (~55%) tested positive for AI-2. Approximately 27% of growth challenges conducted among 19 isolates showed significant growth inhibition. These findings demonstrate that QS is actively occurring within the BBD microbial mat and that culturable bacteria from BBD and the coral SML are able to produce QS signals and antimicrobial compounds. This is the first study to identify AHL production in association with active coral disease.
140

Coral-Algal Symbioses in Mesophotic Montastraea cavernosa in the Gulf of Mexico

Unknown Date (has links)
Mesophotic reefs represent biodiverse ecosystems that may act as a refuge for depth-generalist coral species threatened in shallow habitats. Despite the importance of coral-algal symbioses, few studies focus on mesophotic zooxanthellae assemblages and their influence on connectivity. This study compared zooxanthellae in Montastraea cavernosa at shallow and mesophotic depths at Flower Garden Banks National Marine Sanctuary and McGrail Bank. Mesophotic corals contained more zooxanthellae and more chlorophyll a and c2 per unit area coral. Increased zooxanthellae within mesophotic corals may represent an adaptive strategy to optimize light capture in low-light environments. Genetic profiles for zooxanthellae assemblages from shallow and mesophotic corals showed similar diversity across banks and between depths. The dominant sequence making up assemblages was identified as Symbiodinium type C1. Similar assemblage diversity suggests that zooxanthellae assemblages will not limit connectivity potential between shallow and mesophotic corals at these reefs. / Includes bibliography. / Thesis (M.S.)--Florida Atlantic University, 2016. / FAU Electronic Theses and Dissertations Collection

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