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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.
11

Application of side-scan sonar in mapping seabed morphology and coral reefs off LIU-CHIEU YÜ

Yan, Shyh-Bin 12 August 2004 (has links)
About the investigation method of the present situation of coral reef at present, the main choice is scuba diving investigation no matter domestic and foreign countries. Take the coral reef of physical examination in Taiwan as example, divers use transects as basic methods to calculate the coverage rate of coral reef and characteristic of the seabed environment and to survey specific fish and quantity of the invertebrate in order to judge the influence that the human activity causes to the coral reef. In above-mentioned methods can really make full and accurate investigation to the coral reef of monitor area, so the method has already been adopted and walked for many years by the domestic and international relevant organization. But its shortcomings are slower investigating speed and lack accurate fixed position methods, and the divers also have hiding danger. However, some characteristics of side-scan sonar system just can mend the weak points of them. For the speed of investigating, our side-scan sonar's survey range can reach the belt area of hundred meters wide in both route sides, so it can substantially improve the speed of investigating. For the accuracy of fixed position, the side-scan sonar system match to GPS can obtain certain longitude and latitude of targets¡]the precision about 10 m¡^. So, this research is using side-scan sonar system to survey the seabed around LIU-CHIEU YU¡]the survey area about 2.6 km2¡^, the steps contain: mapping the distribute condition¡]sand, mud and rock¡^of seabed bottom, then identifying growing coral reef of rocky area, final assessing its feasibility by the process and result of survey. The ultimate purpose is an attempt to provide a new method for coral reef survey. The result of study shows: the seabed bottom around LIU-CHIEU YÜ can be divided into several parts by the difference of acoustics reflectivity. Among them, coral reef covers maximum area, and the area can reach to 1,133,670m2¡]46.4% of effective survey area¡^. In the part of identifying growing coral reef in the acoustics image, this study compares with optics images of TOV and acoustics images of side-scan sonar to establish the characteristics of growing coral reef in the acoustics image. Among them, the tree-like corals have some characteristics about high backscatter, individual risings, tree-like figures and acoustics shadows, unregulated reflection surfaces and complicated color tones in the reflection surface, but the cover-form reefs do not have tree-like figures and acoustics shadows. Then, using the above-mentioned characteristics to identify survey area seabed shows¡GThe cover area of growing coral reef is 547,438 m2¡]22.4% of effective survey area¡^, and the growing coral reef distributes in the southwest, southern and eastern sea area of LIU-CHIEU YÜ. And the optics images of the TOV shows the growth state of growing coral reef in the southeast sea area is superior to the southwest sea area, Finally, assessed by the process and result of this research, basically it is feasible to map the distribute condition of growing coral reef by side-scan sonar system.
12

Carbon turnover and accumulation by coral reefs

Kinsey, Donald William January 1979 (has links)
Photocopy of typescript. / Thesis (Ph. D.)--University of Hawaii at Manoa, 1979. / Bibliography: leaves 238-248. / Microfiche. / xii, 248 leaves ill., maps 29 cm
13

Phosphate metabolism of coral reef flats

Atkinson, Marlin J January 1981 (has links)
Bibliography: leaves 86-90 / Microfiche. / viii, 90 leaves, bound ill., maps 29 cm
14

Palytoxin and the mammalian neuromuscular system

Warzynska, Kristina January 1998 (has links)
No description available.
15

An evaluation of the efficiency and accuracy of common coral reef sampling methods.

January 2007 (has links)
Fung, Ho Lam. / Thesis submitted in: November 2006. / Thesis (M.Phil.)--Chinese University of Hong Kong, 2007. / Includes bibliographical references (leaves 343-360). / Abstracts in English and Chinese. / Acknowledgements --- p.i / Abstract --- p.iii / Contents --- p.xii / List of Tables --- p.xix / List of Figures --- p.xxxi / Chapter Chapter 1: --- General Introduction / Chapter 1.1 --- Introduction --- p.1 / Chapter 1.2 --- Objectives --- p.17 / Chapter 1.3 --- Monitoring methods investigated in this research --- p.18 / Chapter 1.4 --- The distribution of corals in Hong Kong --- p.21 / Chapter 1.5 --- Study sites --- p.23 / Chapter 1.6 --- Thesis Outline --- p.25 / Chapter Chapter 2: --- "Coral Mapping in Cheung Sha Wan, A Ye Wan and A Ma Wan, Tung Ping Chau" / Chapter 2.1 --- Introduction --- p.31 / Chapter 2.2 --- Study sites --- p.37 / Chapter 2.3 --- Methods and Materials --- p.38 / Chapter 2.3.1 --- Fieldwork procedure --- p.38 / Chapter 2.3.2 --- Laboratory work procedure --- p.40 / Chapter 2.3.3 --- Data analysis --- p.40 / Chapter 2.4 --- Results and Discussion --- p.42 / Chapter 2.4.1 --- Species count --- p.42 / Chapter 2.4.2 --- Coral coverage --- p.42 / Chapter 2.4.3 --- Species composition --- p.43 / Chapter 2.4.4 --- Diversity index --- p.43 / Chapter Chapter 3 --- "Evaluation of Monitoring Methods in Cheung Sha Wan, Tung Ping Chau, a Coral Community with Low (< 10%) Coral Cover" / Chapter 3.1 --- Introduction --- p.52 / Chapter 3.2 --- Materials and methods --- p.61 / Chapter 3.2.1 --- Line Intercept Transect (LIT) Method --- p.62 / Chapter 3.2.2 --- Point Intercept Transect (PIT) Method --- p.62 / Chapter 3.2.3 --- Random Point Video Transect (RPVT) Method --- p.63 / Chapter 3.2.4 --- Quadrat (QUAD) Method --- p.64 / Chapter 3.2.6 --- Sampling effort in each monitoring method --- p.65 / Chapter 3.2.7 --- Sample size determination --- p.66 / Chapter 3.2.7.1 --- Optimal sample size --- p.66 / Chapter 3.2.7.2 --- Unit effort sample size --- p.67 / Chapter 3.2.8 --- Statistical analysis --- p.68 / Chapter 3.2.8.1 --- Univariate analysis --- p.68 / Chapter 3.2.8.2 --- Multivariate analysis --- p.69 / Chapter 3.4 --- Results --- p.70 / Chapter 3.4.1 --- Optimal sample size --- p.70 / Chapter 3.4.1.1 --- Percent coral cover --- p.71 / Chapter 3.4.1.2 --- Species count --- p.72 / Chapter 3.4.1.3 --- Diversity indices --- p.72 / Chapter 3.4.1.4 --- Community structure --- p.73 / Chapter 3.4.2 --- Sampling efforts in different monitoring methods --- p.75 / Chapter 3.4.3 --- Sample size under fixed effort --- p.76 / Chapter 3.4.3.1 --- Percent coral cover --- p.77 / Chapter 3.4.3.2 --- Species count --- p.78 / Chapter 3.4.3.3 --- Diversity indices --- p.78 / Chapter 3.4.3.4 --- Community structure --- p.80 / Chapter 3.5 --- Discussion --- p.84 / Chapter 3.5.1 --- Optimal sample size --- p.84 / Chapter 3.5.2 --- Coral cover --- p.86 / Chapter 3.5.3 --- Species count --- p.90 / Chapter 3.5.4 --- Diversity Indices --- p.93 / Chapter 3.5.5 --- Community structure --- p.96 / Chapter Chapter 4 --- "Evaluation of Monitoring Methods in A Ye Wan and A Ma Wan, Tung Ping Chau: Coral Communities with Mid to High Percent Coral Cover (25% to 50%)" / Chapter 4.1 --- Introduction --- p.146 / Chapter 4.2 --- Methods and material --- p.149 / Chapter 4.2.1 --- Field monitoring --- p.149 / Chapter 4.2.2 --- Laboratory work --- p.149 / Chapter 4.2.3 --- Sampling effort in each monitoring method --- p.150 / Chapter 4.2.4 --- Sample size determination --- p.150 / Chapter 4.2.5 --- Statistical analysis --- p.151 / Chapter 4.2.5.1 --- Univariate analysis --- p.151 / Chapter 4.2.5.2 --- Multivariate analysis --- p.152 / Chapter 4.3 --- Results --- p.152 / Chapter 4.3.1 --- A Ye Wan --- p.152 / Chapter 4.3.1.1 --- Optimal sample size --- p.152 / Chapter 4.3.1.1.1 --- Percent coral cover --- p.154 / Chapter 4.3.1.1.2 --- Species count --- p.154 / Chapter 4.3.1.1.3 --- Diversity indices --- p.155 / Chapter 4.3.1.1.4 --- Community structure --- p.155 / Chapter 4.3.1.2 --- Sampling efforts in different monitoring methods --- p.157 / Chapter 4.3.1.3 --- Sample size under fixed effort --- p.158 / Chapter 4.3.1.3.1 --- Percent coral cover --- p.158 / Chapter 4.3.1.3.2 --- Species Count --- p.159 / Chapter 4.3.1.3.3 --- Diversity indices --- p.160 / Chapter 4.3.1.3.4 --- Community structure --- p.162 / Chapter 4.3.2 --- A Ma Wan --- p.165 / Chapter 4.3.2.1 --- Optimal sample size --- p.165 / Chapter 4.3.2.1.1 --- Percent coral cover --- p.167 / Chapter 4.3.2.1.2 --- Species count --- p.167 / Chapter 4.3.2.1.3 --- Diversity indices --- p.168 / Chapter 4.3.2.1.4 --- Community structure --- p.169 / Chapter 4.3.2.2 --- Sampling efforts in different monitoring methods --- p.171 / Chapter 4.3.2.3 --- Sample size under fixed effort --- p.172 / Chapter 4.3.2.3.1 --- Percent coral cover --- p.172 / Chapter 4.3.2.3.2 --- Species Count --- p.173 / Chapter 4.3.2.3.3 --- Diversity indices --- p.174 / Chapter 4.3.2.3.4 --- Community structure --- p.175 / Chapter 4.4 --- Discussion --- p.178 / Chapter 4.4.1 --- Optimal sample size --- p.178 / Chapter 4.4.2 --- Coral Cover --- p.178 / Chapter 4.4.3 --- Species Count --- p.181 / Chapter 4.4.4 --- Diversity Indices --- p.182 / Chapter 4.4.5 --- Community Structure --- p.184 / Chapter Chapter 5 --- Role of Community Characteristic on the Performance of Monitoring Methods / Chapter 5.1 --- Introduction --- p.281 / Chapter 5.2 --- Methods and materials --- p.284 / Chapter 5.2.1 --- Coral Mapping --- p.284 / Chapter 5.2.2 --- Monitoring Methods --- p.285 / Chapter 5.2.3 --- Statistical analysis --- p.286 / Chapter 5.3 --- Results --- p.286 / Chapter 5.3.1 --- Sample size as a function of different reef characteristics --- p.286 / Chapter 5.3.2 --- Performance of reef monitoring methods in sites with different reef characteristics --- p.287 / Chapter 5.3.2.1 --- Coral cover --- p.287 / Chapter 5.3.2.2 --- Species count and Margalef's Index --- p.288 / Chapter 5.3.2.3 --- Other diversity indices --- p.289 / Chapter 5.3.2.4 --- Community structure --- p.290 / Chapter 5.4 --- Discussion --- p.291 / Chapter 5.4.1 --- Effect of reef characteristics on sampling time --- p.291 / Chapter 5.4.2 --- Effect of reef characteristics on the performance of monitoring methods --- p.293 / Chapter 5.4.3 --- Recommendation on the choice of monitoring method --- p.301 / Chapter Chapter 6 --- Summary and Prospectives --- p.337 / References --- p.343
16

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.
17

Submarine diagenesis of the corals of the Bellairs reef, Barbados

Boucher, Dennis A. January 1977 (has links)
No description available.
18

Changing Reef Values: An Inquiry into the Use, Management and Governances of Reef Resources in Island Communities of the Maldives

Mohamed, Mizna January 2012 (has links)
The thesis is an exploration into the ways in which island communities living in coral reef environments value the surrounding reef resources. This research is conducted in seven communities in the Maldives. A qualitative approach is used as this inquiry involves gaining insight of human perceptions and behaviours. Discussions and interaction with participants in community activities and participant observation were the main inquiry methods used. Specifically, the research focuses on sand from the beach, coral from the house reef and fish in the island lagoon. The exploration of reef values show that multiple reef values exist and they are constantly changing. How communities interact with the resources and how the communities itself had changed over time contribute to this change in resource value. Physical and social factors, such as resource type, availability and location, physical characteristics of islands, community size, and socio-economic conditions, contribute to the changing reef values. Based on these changing values, it is recommended to go beyond one formal governance rules that fits all. Instead local adaptations based on local ways of valuing need to be considered. A most notable change impacting reef values is the migration of families to the capital. This reduces their interactions both with the reef environment and other community members. In addition, the current globalised education is causing the development of a predominantly globalised worldview among the present generations. In this new worldview, the sacred is separated from the secular. Thus, spiritual and moral beliefs have become isolated from resource management practices. I also find it of concern that local worldviews are being negated at the expense of concern for the global environment. I highlight the importance of schooling to instil knowledge about our local environments and local worldviews. It is also through education we can re-integrate the sacred into our practices and such changes need to be starting at an individual level.
19

Integrated coastal management in the tropics : identifying the impediments and evaluating management tools

Westmacott, Rachel Susan January 2001 (has links)
Tropical coastal resources including coral reefs, mangroves and seagrass beds are some of the most productive ecosystems in the World. They support a variety of goods and services that may often form the backbone of the local community. In many cases they provide the main source of food, as well as providing employment and recreation opportunities. However, coastal ecosystems are increasingly under threat from high population growth rates, rapid coastal development, over exploitation of the resources, loss of critical habitats and vulnerability to natural hazards. These tropical ecosystems are sensitive and vulnerable to damage and environmental change. Their worldwide loss has led to cause for concern and widespread calls for improved management. Integrated coastal management (ICM) is seen as the way forward in dealing with this complex mix of interests, activities and demands being placed on today's coastal zones. The definition of the coastal zone will vary between locations, ideally capturing and enabling the resolution of all major coastal issues, reaching as far inland or seaward as is required to reach the goals and objectives of the management programme. ICM encompasses the management of all aspects of the coastal zone taking a multi-disciplinary approach. It includes the management of existing economic activities, planned developments, natural resource conservation and utilisation as well as being able to deal with the different user conflicts. ICM involves the integration of different institutions and stakeholder groups at and across the local to international management levels. Even though ICM efforts are increasing, there are few examples where it is really being implemented and working effectively. In this study, three ICM case studies identified similar patterns of impediments although their scope was recognised as too narrow to make generalisations. As a result, a survey was developed to build up a broader picture of the issues blocking the development of successful ICM at several locations. The survey identified the current status of ICM in the tropics and identified the main impediments to implementing effective ICM. The survey found that few locations were actually implementing, monitoring and evaluating ICM, however a number were in the process of it. It was the step between analysis and implementation that was halting many of these efforts. Tropical coastal zones can be seen to share a number of common challenges exacerbated by poverty and conflicts between coastal users. Conflict management needs to be incorporated into the management process in a way that pays particular attention to the over-extraction of resources and destructive resource use. Although the concept of integrated coastal management (ICM) has been identified as the way to deal with the multiple objectives, interests and uses of the coastal zone, in practice it is a complex process and many countries are having difficulty in implementing ICM. The most common impediments to ICM in the tropics were identified through the survey as were their impact on implementing ICM. The extent to which ICM is achieved can be linked to the impediments, described by a series of criteria, which could be used in assessing the ability of an area to implement ICM as well as identifying priority areas for concern. The results show that although public participation is commonly accepted as a major part of ICM and is one of the main impediments, it is rarely fully realised. Gaining political support and empowering agencies with sufficient authority to enforce ICM were also identified as major impediments, without which ICM efforts may well be blocked. Decision making for integrated coastal managementin volves multiple decision makers and multiple stakeholders, often with conflicting needs and interests. Decision support systems (DSS) can be developed to improve our understanding of the inter-relationships between the natural and socioeconomic variables and hence result in improved decision making. The question is whether this decision making environment is actually too complex for the development of useful and useable decision support systems. An ICM-DSS needs to be able to involve multiple decision makers and take into consideration multiple issues. This requires different disciplines to be drawn together into an integrated modelling framework. There are many techniques available to deal with different modelling needs, the constraints of inadequate data and the multi-objective decision making environment. There are also different ways of developing decision support systems and each can play a different, but nonthe- less important role within ICM. Three coastal DSSs were evaluated in terms of their design and roles in integrated coastal management and are used to evaluate the potential to develop ICM-DSSs. One of these DSSs, CORAL, is examined in detail as a case study. The model is an example of an integrated ICM model where the final result is a score-card of criteria that measure economic, environmental, social and institutional objectives. CORAL was developed for the island of Curacao in the Caribbean and the Republic of the Maldives. The development process involved stakeholder meetings and interviews to ensure that all their interests and concerns in the coastal zone were accounted for and included in the DSS. The model development was carried out in the Netherlands and on return was presented to the stakeholder groups. A second phase of the project in Curacao allowed the model to be installed on a wide number of computers. An ICM course was established as well as individual training given to the stakeholder groups involved. However, the final use of the DSS was still limited. Lessons are drawn from the CORAL experience that may assist in the development of future DSSs such as the need to involve a key organisation in the development and enable them to continue its development and maintenance after the end of the project. In addition, flexibility, adaptability and update-ability are paramount if the system is to be used beyond educational goals. The impact of ICM on a coastal system is not always readily measured and quantified, least of all in monetary terms. Economic valuation is being increasingly applied to tropical coastal ecosystems to assess their benefits in monetary terms. From the point of view of ICM, economic valuation could give monetary values to, for example, changes in production resulting from management and hence highlights the importance of management. Likewise, it can highlight the costs of inaction by quantifying the benefits of a situation with ICM and one without ICM. This not only requires the ability to link monetary values to certain environmental situations but also to model the potential changes in goods and services provided by the ecosystem as a result of management. Past analyses in ICM have often focused on the costs of management versus economic gains while change to the environment has been measured in physical terms. Economic valuation provides a potential to compare like with like and hence bring the importance of ecosystems, such as coral reefs, to the fore. Some goods provided by these coastal ecosystems are marketed and consequently have a marketdefined value associated with them. However, these ecosystems also provide a number of non-use benefits, which are not directly marketed and as a result, certain economic techniques have been developed to deal with these issues. The contingent valuation methodology (CVM) was developed as a tool to measure non-marketed goods and services of ecosystems so they can be included into costbenefit analyses. However, it is a complex technique surrounded by much controversy.
20

Interactions Between Sea Water and Coral Reefs in Kaneohe Bay, Oahu, Hawaii

Klim, Donald G 01 June 1969 (has links)
TIlis study, covering a period of eight months, was undertaken to determine if measurable changes in characteristics occur in sea water passing over a shallow coral reef. The parameters studied include salinity, temperature, current velocities, dissolved oxygen, pH, dissolved organic carbon and particulate organic and suspended inorganic carbon. Staining and microscopic observations were made to supplement the other data. The results showed noticeable increases in oxygen, pH, particulate organic and inorganic carbon abundance in the central portion of the reef, which were attributed to the influence of extensive growths of benthic algae found on the seaward edge. Dissolved organic carbon concentration increased gradually across the reef, and there is evidence that inorganic carbonate is being accumulated on the leeward side of the reef. / Typescript. Bibliography: leaves [53]-55.

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