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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.
71

The ecology of tapes philippinarum (Bivalvia: Veneridae) in Starfish Bay, Hong Kong, and its potential as a biological indicator of coastalpollution

Cha, Mei-wah., 車美華. January 1994 (has links)
published_or_final_version / Zoology / Doctoral / Doctor of Philosophy
72

Modeling marine environmental impacts in Hong Kong with GIS

Thorpe, John Paul. January 1996 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
73

Afsterwe van mikroorganismes teenwoordig in rioolwater in die mariene omgewing / Die-off of micro-organisms present in sewage in the marine environment

Engelbrecht, Johannes Frederik Pieter January 1990 (has links)
Thesis (M.Dip.)--Cape Technikon, 1990 / The die-off in the marine environment of micro-organisms that are present in sewage was investigated. A literature survey was carried out and studies were done in the laboratory, at an offshore outfall and at a surf-zone outfall. In the laboratory raw sewage was mixed with sea water at known dilutions and the die-off of faecal coliforms, faecal streptococci and coliphage was monitored. At the offshore sewage outfall a tracer, Rhodamine B.was released in the pump station and the distribution of the plume around the diffuser was determined by means of the Rhodamine B concentrations and faecal colifonns counts. At the factory surf-zone outlet the Rhodamine B was injected into the pipeline. Samples were taken at 50 and 100 meter distance from the outlet. Thedie-off of faecal colifonns, faecal streptococci and coliphage was monitored. The following results were obtained: Literature study: (i) Coliforms • Temperatures of 15 QC and lower are conducive to survival while nutrients, at a concentration as low as 2,5 mg/L organic carbon, stimulate growth. A rise in salinity has a negative effect on the organisms. • The T90 value in direct sunlight is <2 hours but vanes considerably in the dark (>35 days). Changes in weather• conditions, sunlight intensity, hours of sunlight, depth and turbidity of seawater and different seasons are the most important factors accounting for the variations in the T90 values. • It is, therefore, important for the initial dilution to be large enough. This will ensure that the bacterial counts conform to the water quality criteria, as the die-off rates in the marine environment are slow and not always adequate, except around mid day. • Faecal coliforms as a single parameter is not considered to be the best indicator of marine pollution. • The 1:4 ratio between faecal coliforms and faecal streptococci for human faeces and 1:0,7 ratio for animal waste are not applicable in the marine environment. The survival of faecal streptococci in seawater is better than that of faecal coliforms and the ratio therefore changes. (ii) Enterococci and pathogens • The T90 value for faecal streptococci is double that of coliforms and also varies in the dark. In direct sunlight any change in sunlight intensity, change the T90 values. • In general the numbers of faecal streptococci and pathogens occuring in sewage are smaller than those of coliforms, but their survival time is longer. This could lead to a situation where the water quality complies with the criteria according to the coliform counts, while a health risk may exist due to th survival of pathogens.
74

Effects of sublethal nitrite concentrations on the metabolism of the sea bass, Lates calcarifer.

January 1989 (has links)
by Chiu Shui-fan. / Thesis (M.Phil.)--Chinese University of Hong Kong, 1989. / Bibliography: leaves 186-203.
75

Health risk of bathing in Southern California coastal waters /

Brinks, Mitchell V. January 1900 (has links)
Thesis (M.P.H.)--Oregon State University, 2008. / Printout. Includes bibliographical references. Also available on the World Wide Web.
76

Studies on the management of marine debris in Taiwan

Chuang, Ching-chiang 02 July 2010 (has links)
The fast coastal development has caused serious marine pollution with powerless policy and inappropriate management scheme, especially in dealing with the marine debris. The marine debris has been the major coastal problems over the year because of human related activities and nature disasters frequently occurring during the monsoon season or typhoon period each year around the coastal Taiwan. These make the marine debris issues to become the top priority for the government of Taiwan in dealing the marine pollution especially after the 8th of August, 2009. The present study is initiated to assess the current data information, policy, and regulation of Taiwan¡¦s coastal area debris management. This study uses comparative analysis, integrations of internal and external monitoring and management of marine debris-related researches. This thesis reports that Taiwan administration must undertake all three aspects of integration, monitoring and management to effectively managing the marine debris. As the aspect of integration, because marine debris come from land-based emissions, ocean currents carry and sea-based activities, the government needs to consolidate the entire river, rain water drainage systems, ports, ships and fishing areas, to establish an inter-ministerial and responsible agency, to truly develop and implement the bill of marine debris management. As the aspect of monitoring, the central and local government as well as civil society must do their best together to develop the monitoring operations format which needed both considering national unity and local differences, to take long-term continuous monitoring of all major coastal areas, to clarify the source of marine debris, so that government could effectively control the sources of marine debris. As the aspect of management, since the a variety of marine debris sources and diversity of monitoring, the inter-ministerial and responsible agency not only coordinates the various related fields, but also combines the public and private sectors, to truly implement the bill of marine debris management. Overall, Taiwan government must use a variety of economic incentives, cooperation issues and the law, as well as combines the strength of the IV private sectors to effectively manage the management of marine debris.
77

Polybrominated diphenyl ether flame retardants in the antarctic environment

Yogui, Gilvan Takeshi 15 May 2009 (has links)
Polybrominated diphenyl ethers (PBDEs) are anthropogenic chemicals whose environmental behavior is similar to the well-known polychlorinated biphenyls (PCBs). Few studies have quantified the amount and distribution of PBDEs in the southern hemisphere and Antarctica. The analyses reported in this dissertation document the levels of PBDEs in lichens, mosses and seabird eggs collected at King George Island, Antarctic Peninsula. The analyses were carried out using Gas Chromatography/Electron Impact-Mass Spectrometry (GC/EI-MS). Employing the ion stacking technique lowered detection limits and ensured instrument selectivity and sensitivity to the compounds of interest. Lichens and mosses absorb PBDEs directly from the atmosphere and their contamination indicates that long-range transport is the primary source of these chemicals to King George Island. The congener patterns of PBDEs in plants indicate that commercial mixtures of Penta-BDE and Octa-BDE have reached Antarctica. Differences in the levels of PBDEs observed in lichens and mosses are probably due to factors that govern the uptake of PBDEs from the atmosphere. Contamination in lichens showed a positive correlation with local precipitation. Conversely, absorption of PBDEs in mosses appears to be controlled by other plant-specific factors. Marine phytoplankton-derived aerosols are hypothesized to play an important role in the atmospheric transport of PBDEs to the Antarctic environment. PBDEs in south polar skua eggs revealed much higher concentration than in penguin eggs. This is likely associated with the northward migration of these seabirds during the non-breeding season. While penguins reside year-round in Antarctica, south polar skuas migrate northward and can be seen in boreal oceans during the austral winter. Distribution of PBDEs in penguin eggs matches the pattern found in local vegetation suggesting a common source for the chemicals. In contrast, the congener pattern of south polar skuas suggests that birds breeding at King George Island are wintering in the northwestern Pacific Ocean. A potential metabolism of PBDEs in penguin eggs during the incubation period seems to be limited. Most congeners were unaltered from source material in the eggs of chinstrap and gentoo penguins. Low levels of PBDEs, short incubation periods and energy constraints may explain these observations.
78

Analysis and prediction of beach water quality in Hong Kong with special reference to Big Wave Bay Beach /

Wong, Ho-chuen. January 2009 (has links)
Thesis (M. Phil.)--University of Hong Kong, 2010. / Includes bibliographical references (p. [137]-142). Also available in print.
79

Metal concentrations (AS, CD, CR, PB, HG and SE) in Dolly Varden (Salvelinus malma) from the Aleutian Islands, Alaska

Jeitner, Christian, January 2009 (has links)
Thesis (M.S.)--Rutgers University, 2009. / "Graduate Program in Ecology and Evolution." Includes bibliographical references (p. 56-76).
80

The relationship between el niño Southern oscillation and levels of paralytic shellfish poisoning present in Washingtons marine waters

Lumper, Randy N. January 2008 (has links) (PDF)
Thesis (M.E.S.)--The Evergreen State College, 2008. / Title from title screen (viewed 2/25/2010). Includes bibliographical references (leaves 68-70).

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