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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

The relationship between bleaching of Acropora grandis and hydrological factors in the coastal area of Kenting, Taiwan.

Ho, Chun-Chung 18 February 2003 (has links)
Abstract The coral reef ecosystem is known to have high diversity and productivity such as rainforest on land. There is a fringing coral reef located in the Kenting National Park in Taiwan. However, from July 1987, the corals near a nuclear powder plant were frequently bleached in summer. In this research, we had used Acropora grandis as an indicator to study the relationship between the bleaching events of coral with environmental parameters during 1994 to 1998. The results showed that the corals exhibited serious bleaching when the ambient temperature was high. The other environmental parameters were relatively irrelevant. However, during the cool seasons, from January to May, the chl. a of the corals at the right side of warm water effluent, was even than those of the control, showing a better growth result from the warmer temperature. Further analysis showed that bleaching was correlated with water temperature, regional precipitation and sea surface temperature with one and two month before the event, yet not with those of the same month. Human activity in the coastal area was another important factor that caused the deterioration of local coral reef.
2

Effects of Zinc and Vitamin Supplementation on the Coral Acropora hemprichii Health and Growth.

Alabyadh, Ali 07 1900 (has links)
Coral reefs are complex ecosystems that provide several ecological, environmental, and economic services. However, climate change has heavily threatened these ecosystems, particularly due to increasing sea surface temperature. Innovative solutions to improve coral tolerance to climate change are therefore urgently needed. Vitamin and trace element supplements can improve the fitness of several animals (e.g., fish and crustaceans) in aquaculture systems, and could represent an alternative treatment to improve coral health and growth in coral nurseries. Here, we tested whether the supplementation of vitamins B6, B12, and zinc could boost coral growth, and health. For this purpose, fragments (n=10) of colonies of five Acropora hemprichii were collected from the central Red Sea were treated with B6, B12, zinc, and a combination of these supplements for 21 days. Coral fragments were collected before and after the experiment. Calcification and oxygen metabolism (respiration, photosynthesis) were measured, while symbiont density, chlorophyll, total protein, and carbohydrate were quantified in the lab. Our data showed that corals’ symbionts density, chlorophyll c2, net productivity, and total protein were significantly increased due to zinc supplementation when compared to control colonies. In addition, the multi-treatment also increased the corals’ total proteins. In contrast, none of the other treatments showed a significant effect on the tested coral’s physiological traits. The results of this study may provide data to support alternative approaches to improve coral growth for restoration efforts.
3

Patterns and processes of reef recovery and human resource use in the Lakshadweep Islands, Indian Ocean /

Arthur, Rohan. January 2004 (has links)
Thesis (Ph.D.) - James Cook University, 2004. / Typescript (photocopy) Bibliography: leaves 110-130.
4

Effects of density and habitat structure on growth and survival of harvested coral reef fishes /

Wormald, Clare Louise. January 2007 (has links)
Thesis (Ph.D.)--University of Rhode Island, 2007. / Includes bibliographical references (leaves 126-141).
5

Opportunity search in coral trade industry : business opportunity around water related industry in today economic environment /

Wong, Tat-kwong, Dennis. January 1998 (has links)
Thesis (M.B.A.)--University of Hong Kong, 1998. / Includes bibliographical references (leaf 133-136).
6

Influence of Substrate on Coral Reef Fish Communities

Neely, Karen Lynn, January 2008 (has links) (PDF)
Thesis (Ph. D.)--Duke University, 2008.
7

Seaweed allelopathy against coral: surface distribution of seaweed secondary metabolites by imaging mass sepctrometry

Andras, Tiffany D. 16 August 2012 (has links)
Coral reefs are in global decline, with seaweeds increasing as corals decrease. Though seaweeds have been shown to inhibit coral growth, recruitment, and survivorship, the mechanism of these interactions is poorly known. Here we use field experiments to show that contact with four common seaweeds induces bleaching on natural colonies of Porites rus. Controls in contact with inert, plastic mimics of seaweeds did not bleach, suggesting treatment effects resulted from allelopathy rather than shading, abrasion, or physical contact. Bioassay-guided fractionation of the hydrophobic extract from the red alga Phacelocarpus neurymenioides revealed a previously characterized antibacterial metabolite, Neurymenolide A, as the main allelopathic agent. For allelopathy of lipid soluble metabolites to be effective, the metabolites would need to be deployed on algal surfaces where they could transfer to corals on contact. We used desorption electrospray ionization mass spectrometry (DESI-MS) to visualize and quantify Neurymenolide A on the surface of P. neurymenioides and found the metabolite on all surfaces analyzed. The highest concentrations of Neurymenolide A were on basal portions of blades where the plant is most likely to contact other benthic competitors.
8

Spatial Dynamics of Coral Populations in the Florida Keys

Swanson, Dione W 11 August 2011 (has links)
Coral reef degradation has been observed worldwide over the past few decades resulting in significant decreases in coral cover and abundance. However, there has not been a clear framework established to address the crucial need for more sophisticated understanding of the fundamental ecology of corals and their response to environmental stressors. Development of a quantitative approach to coral population ecology that utilizes formal, well established principles of fishery systems science offers a new framework to address these issues. The goal of this dissertation is to establish a quantitative foundation for assessment of coral reefs by developing some essential ecological and population-dynamic components of a size-structured demographic model for coral populations of the Florida Keys coral reef ecosystem. The objective provides the potential to build a quantitative systems science framework for coral populations. A two-stage stratified random sampling design was implemented during two separate survey periods to assess coral populations. Results include precise estimates of adult (> 4 cm) population abundance for several coral species by spatially partitioning abundance and variance into species-relevant reef habitat types. Adult size structure and juvenile abundance were used to evaluate individual coral populations and infer spatial variation in recruitment, growth and survival across habitat types. Partial mortality was characterized in terms of surface area, prevalence, and size-relationships. The development of some ecological and population-dynamic components of a size-structured demographic model for coral populations demonstrates the statistical framework and metrics required for monitoring and assessment of coral reef ecosystems to meet the pressing needs of conservation of coral reef ecosystems specifically in Florida, and throughout the Caribbean and Pacific in general.
9

Hong Kong's scleractinian coral communities : status, threats and proposals for management /

McCorry, Denise. January 2002 (has links)
Thesis (Ph. D.)--University of Hong Kong, 2002. / Includes bibliographical references (leaves 274-304).
10

Community-based and collaborative management of coral reefs and coastal resources in Palau /

Matthews, Elizabeth, January 2007 (has links)
Thesis (Ph.D.)--University of Rhode Island, 2007. / Includes bibliographical references (leaves 295-311).

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