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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

Assessing the importance of biological uncertainties to the control of species introductions via ballast water /

Tavares, Joana Flor R. January 2009 (has links)
Thesis (M.S.)--University of Delaware, 2007. / Principal faculty advisor: Jeremy M. Firestone, College of Marine & Earth Studies. Includes bibliographical references.
2

Bacteria in Ballast Water: The Shipping Industry's Contributions to the Transport and Distribution of Microbial Species in Texas

Neyland, Elizabeth B. 2009 August 1900 (has links)
The transportation of organisms in the ballast water of cargo ships has been recognized as a source of invasive species despite current control measures. Pathogenic bacteria in the ballast tank have been studied but the total diversity of the ballast tank bacterial community has not been examined. This study is the first to characterize the total bacterial community within a ballast tank by constructing a clone library from a ballast water sample from a cargo ship in the Port of Houston, amplified ribosomal rDNA restriction analysis (ARDRA) and phylogenetic analysis. Bacterial communities in Texas ports and bays were also examined using denaturing gradient gel electrophoresis (DGGE), looking at both temporal and spatial variations for effects of deballasting activity. This ballast tank bacterial community had a high level of diversity (95%) with the clone library only representing 40% of the total community of the tank. Most probable originating habitats of the ballast bacteria were: marine pelagic (40%), estuarine (37%), coastal (6%), freshwater (3%) and other (14%), even though this ballast tank was exchanged with pelagic water. Predominate groups were alpha- and gammaproteobacteria, a few betaproteobacteria and bacteriodetes, and one each of verrucomicrobia, planctomycetes and actinobacteria, but no pathogens were detected. The data reveals a ballast tank that consists of half marine-pelagic, half port bacteria, revealing a low efficacy of exchange control methods and potentially invasive bacteria. The bacterial communities of five ships that exchanged ballast water in the Pacific Ocean shared on average 50% similarity. Two ships that exchanged ballast water in temperate latitudes were more similar than three other ships that exchanged in tropical latitudes, showing a correlation between location of exchange and community similarity. The bacterial communities of the Ports of Houston and Galveston exhibit stable, seasonal successions over one year. The port and bay systems of Texas exhibited spatial variations in bacterial communities related to salinity levels. Both experiments did not show evidence of community disruption by deballasting activities. This study shows that ballast water is a viable vector for invasive bacterial transport, although impact on Texas estuarine systems seems minimal.
3

A Study on the Taiwan Shipping Industries' Perception of the BWM Convention

Wu, Ying-ying 22 January 2009 (has links)
A Study on the Taiwan Shipping Industries' Perception of the BWM Convention for the BWM Convention Abstract The global trade's commodity has 80% is by the marine transportation way loading, is responsible for the transportation industry the ships to maintain the navigation the security is stable; the ballast water tank will be pumping into the massive ballast water to maintain balanced. Had the research discovery, the loading ballast, if after has not processed properly on the emissions inflow harbor, has in the ballast the pathogen or the micro biology, will destroy the local port territory the biodiversity even to initiate threatens the human health disease, will create the serious economic loss. In order to reduce the ballast the emissions initiation pathogen destruction sea ecology, the International Maritime Organization to draw up the International Convention for the Control and Management of Ships Ballast Water and Sediments (BWM Convention) by the public law binding force, so as to protection marine environment. In this studying, the questionnaire is in view of the shipping company, the shipyard, the ships equipment supplier and the maritime affair related organization and so on four communities. According to the investgating result, finds Taiwan shipping interest cognition ratio less than 50% regarding the new international convention, are worth the anxiety. Expected that produces the marine industrial, gonverment and marine educational intrest in Taiwan shipping facing the international ballast control and management tendency by this studying, and provides one to draw up effectively of reference in accordance to the strategy.
4

Evaluation of Ships' Ballast Water as a Vector for Transfer of Pathogenic Bacteria to Marine Protected Areas in the Gulf of Mexico

Morris, Theresa L 03 October 2013 (has links)
An average of three to five billion tons of ballast water (BW) is transported globally per year; 79 million tons of which is released into U. S. waters. Ballast water is necessary for large ships to maintain balance and stability while loading and unloading cargo as well as during transit. As a ship unloads it’s cargo at a port, it takes on ballast water and then when it loads cargo at the next port, it discharges the ballast water, thus transferring water from port to port. Aquatic organisms are transported around the globe via ballast water. These organisms can potentially cause serious environmental and human health impacts. Historically, transfer of macro-organisms such as fish, snails, and vascular plants via ballast water have been the focus of ballast water research. More recently, microorganisms such as toxin producing dinoflagellates and diatoms i.e. ‘harmful algal blooms’ and pathogenic bacteria (e.g. Vibrio cholerae), have been found to survive in ballast tanks for several weeks. These organisms have moved to the forefront of ballast water management (BWM) trepidations because they compose serious threats to human health as well as Marine Protected Area (MPA) ecosystems such as coral reefs. Ballasting activities of ships calling at the Port of Houston were used as a model for other major ports in U.S. Gulf States. Ballast water management reports, submitted to the U.S. Coast Guard by all overseas vessels calling at the Port of Houston in 2010 were examined for the ballast management strategies utilized prior to docking. Currently, all “coastwise” ships are not required to conduct ballast water exchanges (BWE) if they do not transit beyond the 200nm EEZ. Close inspection of BW management report forms for “overseas” ships determined that the degree of completeness was variable. By comparing the frequency of vessels entering the Port of Houston, ballast water capacities, the management types utilized, and the locations of ballast water exchanges and discharges, it can be concluded that larger vessels present the highest risk of bacterial transfer to coral reefs. Five coral diseases were discovered to be prevalent throughout the ballast management areas their presence has significantly increased in these areas over the past thirty years. The combination of this disease growth along with an increase in shipping and ballast exchanges suggests that the vector at which pathogens are being displaced must lie within the shipping lanes.
5

Prediction of turbulent mixing at the interface of density stratified, shear flows using CFD

Umbel, Matthew R. January 1998 (has links)
Thesis (M.S.)--West Virginia University, 1998. / Title from document title page. Document formatted into pages; contains xvi, 184 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 145-147).
6

A droplet formation and entrainment model for stratified liquid-liquid flows

Badeau, Allen E. January 2000 (has links)
Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains xiii, 150 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 140-144).
7

Naturally-occurring chemical tracers in seawater and their application to verifying mid-ocean ballast water exchange.

Murphy, Kathleen Ruth, Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2007 (has links)
Recent regulation mandates that ships conduct mid ocean ballast water exchange (BWE) prior to discharging foreign ballast in territorial waters of Australia, the U.S. and elsewhere. The enforcement of ballast water exchange legislation is undermined, however, by a lack of sensitive and reliable methods for verifying compliance. One way to assess compliance is to compare the concentrations of chemical tracers in ballast tanks with their known distributions in the open ocean. In this work, dissolved organic matter and trace elements are investigated as potential tracers of mid-ocean ballast water exchange on commercial voyages in the North Pacific and Atlantic Oceans. The optical properties of chromophoric dissolved organic matter (CDOM) are frequently used as tracers of water masses in bays and estuaries. Characterization of the underlying fluorescence spectra in seawater dissolved organic matter was performed using parallel factor analysis, allowing the identification of at least nine independently varying fluorescent components present in varying concentrations in the ocean and in ballast water. Two of the humic components were terrestrial in origin and their signals could be traced in the open ocean (Pacific and Atlantic) at levels of approximately 1.5% of riverine concentrations. One humic terrestrial component was sufficient for predicting the coastal vs. oceanic source of most ballast water samples, suggesting that single and dual channel fluorometers could be optimized for verifying ballast water exchange. Barium, manganese and phosphorus were also investigated as potential tracers. Measurements of Ba and P obtained via engine-cooling pipes on commercial vessels were consistent with previous oceanographic measurements. While Ba behaved conservatively in ballast water, concentrations of phosphorus fluctuated and Mn was removed in ballast tanks over time. Ba and P demonstrated considerable promise as ballast water tracers, exhibiting predictable concentrations in exchanged ballast tanks, given a priori knowledge of the ocean (Atlantic versus Pacific) in which BWE was performed.
8

Naturally-occurring chemical tracers in seawater and their application to verifying mid-ocean ballast water exchange.

Murphy, Kathleen Ruth, Civil & Environmental Engineering, Faculty of Engineering, UNSW January 2007 (has links)
Recent regulation mandates that ships conduct mid ocean ballast water exchange (BWE) prior to discharging foreign ballast in territorial waters of Australia, the U.S. and elsewhere. The enforcement of ballast water exchange legislation is undermined, however, by a lack of sensitive and reliable methods for verifying compliance. One way to assess compliance is to compare the concentrations of chemical tracers in ballast tanks with their known distributions in the open ocean. In this work, dissolved organic matter and trace elements are investigated as potential tracers of mid-ocean ballast water exchange on commercial voyages in the North Pacific and Atlantic Oceans. The optical properties of chromophoric dissolved organic matter (CDOM) are frequently used as tracers of water masses in bays and estuaries. Characterization of the underlying fluorescence spectra in seawater dissolved organic matter was performed using parallel factor analysis, allowing the identification of at least nine independently varying fluorescent components present in varying concentrations in the ocean and in ballast water. Two of the humic components were terrestrial in origin and their signals could be traced in the open ocean (Pacific and Atlantic) at levels of approximately 1.5% of riverine concentrations. One humic terrestrial component was sufficient for predicting the coastal vs. oceanic source of most ballast water samples, suggesting that single and dual channel fluorometers could be optimized for verifying ballast water exchange. Barium, manganese and phosphorus were also investigated as potential tracers. Measurements of Ba and P obtained via engine-cooling pipes on commercial vessels were consistent with previous oceanographic measurements. While Ba behaved conservatively in ballast water, concentrations of phosphorus fluctuated and Mn was removed in ballast tanks over time. Ba and P demonstrated considerable promise as ballast water tracers, exhibiting predictable concentrations in exchanged ballast tanks, given a priori knowledge of the ocean (Atlantic versus Pacific) in which BWE was performed.
9

The status of ballast water management in the ports of South Africa.

Calitz, Fiona. January 2012 (has links)
Ballast water discharged from ships is considered to be one of the four biggest threats to oceans, as alien species, detrimental to the marine ecosystems, are introduced into domestic waters via ballast. Nevertheless, eight years after its adoption, the International Convention for the Control and Management of Ship’s Ballast Water and Sediments of 2004 remains unenforced. In the interim, the IMO has encouraged member countries to implement national ballast water policies in order to reduce the risk of alien invasions into their waters. South Africa was chosen as one of six countries in the world to participate as a pilot country for the GloBallast programme which was conducted in Saldanha Bay between 2000 and 2004. The purpose of the GloBallast programme was to assist developing countries to understand, develop and implement control measures relating to ships ballast water within their ports. The outcome of the risk assessment completed during the programme was that South Africa needed to implement a mandatory ballast water reporting system. The purpose of this study is to examine the status of ballast water management in the ports of South Africa and to determine the progress made since South Africa participated in the GloBallast programme. The methodology used in this study included questionnaires distributed to industry experts and the full population of Ships Agents that are members of the South African Association of Ship Operations and Agents. The findings show that whilst each port is reported to have a ballast water management plan; only three of the eight potential plans could be produced. Two of these plans, belonging to the ecosensitive ports of Ngqura and Saldanha Bay, were proven to be well-known amongst the agents. The other ports, however, reflected a weak 50% and lower level of awareness. It was further determined that the ships agents are largely unaware of the responsibilities placed upon them by these plans. The findings further revealed that these regulations have not been monitored or enforced and presently ballast water management would appear to be merely a paper exercise. Those ships agents who are aware and comply with the requirements report that they have never had a problem with obtaining approval to discharge ballast. Recent developments in July 2012 show that the Department of Transport has assembled a team to further develop legislation and regulations to address ballast water management in South Africa. / Thesis (MBA)-University of KwaZulu-Natal, Durban, 2012.
10

Characterizing ballast water as a vector for nonindigenous zooplankton transport

Humphrey, Donald B. 11 1900 (has links)
The global movement of aquatic non-indigenous species can have severe ecological, environmental and economic impacts emphasizing the need to identify potential invaders and transport pathways. Initial transport is arguably the most important stage of the invasion process owing to its role in selectively determining potential invasion candidates. This study characterizes a well defined human-mediated dispersal mechanism, ballast water transport, as a vector for the introduction of non-indigenous zooplankton. Ballast water exchange in the open ocean is the most widely adopted practice for reducing the threat of aquatic invasions and is mandatory for most foreign vessels intending to release ballast in Canadian waters. Ships entering Canadian ports are categorized into the following three shipping classes based on current regulations: overseas vessels carrying exchanged ballast water, intra-coastal vessels carrying exchanged ballast water or intra-coastal vessels carrying un-exchanged ballast water. This study characterizes zooplankton communities associated with each of these shipping classes sampled from ports on Canada’s Pacific coast, Atlantic coast and the Great Lakes Basin. Ballast water samples were collected and analyzed from 77 vessels between 2006 - 2007. The ballast water environment was found to be diverse, with over 193 zooplankton taxa, 71 of which were non-indigenous to their receiving environments. Intracoastal vessels containing un-exchanged coastal water transported the greatest density of non-indigenous zooplankton into Canadian ports. Total zooplankton density was found to be negatively correlated with ballast water age The absence of mandatory ballast water exchange and the younger ballast water age of coastal un-exchanged vessels is likely responsible for the higher density of non-indigenous zooplankton in intracoastal un-exchanged vessels. Propagule pressure, invasion history and environmental suitability are all useful in evaluating invasion potential and all suggest that intracoastal un-exchanged vessels pose the greatest invasion threat to Canadian aquatic ecosystems. In conclusion, although the risk of primary introductions from overseas ports may have been reduced through open-ocean exchange of ballast water, secondary introductions from previously invaded ports in North America may be the primary threat to Canadian aquatic ecosystems via this transport vector.

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