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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

Small plastic debris on beaches in Hong Kong an initial investigation /

Zurcher, Nico Andreas. January 2009 (has links)
Thesis (M. Sc.)--University of Hong Kong, 2009. / Includes bibliographical references (p. 49-61).
2

Amphipods are a strong interactor in the foodweb of a brown-water salmon river

Thompson, Audrey Marie. January 2007 (has links)
Thesis (M.S.)--University of Montana, 2007. / Title from title screen. Description based on contents viewed Sept. 9, 2008. Includes bibliographical references (p. 52-55).
3

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.
4

Domestic and international environmental policy in Mexico : compounding issues for the marine environment

Rupe, Blake R. 01 May 2014 (has links)
Mexico is home to almost 2.9 million square kilometers of land and water surface area that is affected by water pollution and environmental degradation. While geographically more prevalent to pollution threats as well as one of the most biodiverse countries in the world, it is important to coordinate the management and regulation of coastal zones effectively to safeguard these ecosystem from degradation. However, because of the UN Convention on the Law of the Sea, nations view the problem of living resources and their management as a national priority instead of an international cooperation initiative. Mexico's fragmented, overlapping, and sometimes corrupt domestic institutions for environmental policy yield ineffective and inadequate pollution control, a result of which is a high level of marine debris presence on the coasts, as evidenced by a recent study in Veracruz, Veracruz. This marine debris, the most abundant of which is composed of plastics, is detrimental to marine life, leading to death, starvation, debilitation, reduced quality of life and lowered reproductive performance. While several avenues are being explored to mitigate marine debris in the environment, such as decreasing knowledge gaps, increasing pollution prevention measures, and education, degradation issues have compounded globally, revealing a clear picture of inadequate international regulation and convention. A stricter Mexican national regulatory system that incorporates private and public waste management organizations to incentivize and facilitate waste cleanup is needed to improve the health of the global ocean.
5

Distribution and direct impacts of marine debris on the Mississippi commercial shrimping

Rodolfich, Alyssa 06 August 2021 (has links)
Commercial shrimpers in the Mississippi Sound frequently encounter marine debris in their nets, which results in loss of time, loss of catch, and added repair costs. Yet, the spatial and temporal distribution of this marine debris and the economic impact faced by shrimpers in the Mississippi Sound is not well known. This study measured the quantity and economic impact of marine debris by surveying 20 commercial shrimpers. Participants logged marine debris encounters, fishing data, and damage to fishing gear during the July 2020 through December 2020 shrimping season. It was found that shrimpers encounter marine debris 19% of all tows, and the majority of all marine debris encountered by shrimpers (79%) was derelict crab traps. Additionally, 10% of all tows reported direct impacts.
6

Marine waste in Hong Kong

Lam, Ho-cheung., 林浩祥. January 2003 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
7

Small plastic debris on beaches in Hong Kong: an initial investigation

Zurcher, Nico Andreas. January 2009 (has links)
published_or_final_version / Environmental Management / Master / Master of Science in Environmental Management
8

Observation et modélisation des macro-déchets en mer Méditerranée, de la large échelle aux échelles côtière et littorale / Observation and modelling of the macro-waste in the Mediterranean Sea, from the large Scale to the coastal and local Scales

Mansui, Jérémy 14 December 2015 (has links)
L'objectif général de cette thèse est d'étudier les mécanismes de transport des déchets marins flottants ainsi queleur accumulation potentielle en Méditerranée, en s'appuyant sur la modélisation numérique de leur dérive ainsique sur des observations in-situ de leur distribution. La dynamique du transport des déchets marins y estnotamment analysée en terme d'échelles caractéristiques du bassin, en partant de la grande échelle jusqu'auxéchelles côtière et littorale.Dans un premier temps, l'examen d'un ensemble d'expériences Lagrangiennes numériques a permis d'identifierdans le bassin des zones probables d'accumulation non permanentes à grande échelle (Mansui et al., 2015a).L'impact à l'échelle côtière d'un courant de bord (Courant Nord) et des forçages atmosphériques sur ladistribution locale et l'échouage des déchets marins flottants a ensuite pu être estimé en utilisant notammentdes données originales recueillies en mer et à terre (Mansui et al., 2015b, en révision). / The main objective of this work is to study the floating marine debris transport mechanisms and their potentialaccumulation in the Mediterranean Sea, using numerical modelling and in-situ observations of debris. Thetransport dynamics is analysed in terms of typical scales in the basin, from the large scale to the coastal andlocal scales.First, the analysis of a Lagrangian experience data set show the potential existence of non-permanent and largeretention areas (Mansui et al., 2015a). In a second stage, the coastal impact of a boundary current (the NorthernCurrent) and atmospheric forcings on the local distribution and stranding of floating marine litter has beenestimated (Mansui et al., 2015b, under revision), using an original set of data combining offshore sightings andbeaching surveys.
9

Seabirds as indicators of change in the eastern Canadian Arctic

Provencher, Jennifer 31 August 2010 (has links)
Climate change has a wide range of effects with the potential to cause broad changes in marine ecosystems. The Arctic is predicted to be one of the most highly impacted areas, with average temperatures increasing by as much as 3-5°C. As temperatures rise, Arctic sea ice is disappearing earlier each year, leading to changes in the ocean environment. Thick-billed murres (Uria lomvia) (TBMU) and northern fulmars (Fulmarus glacialis) were collected at colonies in the eastern Canadian Arctic to examine potential changes in Arctic marine food webs over the past three decades. Otoliths and invertebrates were examined in the murre stomachs, and the results compared to data collected from the same colonies in the 1970s and 1980s. Few changes were observed in the diets of the high Arctic thick-billed murres where the ice-associated Arctic cod continue to dominant the prey items found in the thick-billed murres. Significant changes were found in birds sampled from the low and mid-Arctic. In the low Arctic, Arctic cod has declined across all of the colonies sampled, while the capelin, which is a sub-Arctic species, has become dominant in the diets of the birds in the low Arctic and a common prey species mid-Arctic where it was not observed in the diet of TBMUs previously, indicating a northward expansion of this species. The proportion of invertebrate species has changed in some zones and mysids now constitute a large proportion of the murre diet in the low and mid Arctic where hyperid and gammarid amphipods used to be the main invertebrate consumed. The birds can be used as samplers of the marine environment, and as integrators of the environmental changes that are occurring, but prey were not the only items found in the stomachs on birds sampled. Marine plastic debris was also found in the stomach contents of both murres and fulmars from every colony sampled indicating plastic ingestion is becoming a widespread problem for Arctic seabirds. Plastics found in northern fulmars indicate that marine plastic debris is increasing in the Arctic Archipelago, and monitoring of this recognized indicator species of plastic debris will allow long term monitoring of man-made debris in Canada’s north. Plastic debris was also found in thick-billed murres from all of the colonies sampled. Although murres are not useful indicators of general marine plastic debris the presence of plastics at all the colonies sampled indicate that plastics are not just a problem for surface feeding seabirds, but a threat to a number of species found in Canadian waters.
10

Avaliação de microplásticos em praias da Baía de Guanabara, Rio de Janeiro, RJ, Brasil / Assessment of microplastic in beaches of Guanabara Bay, Rio de Janeiro, RJ, Brazil

Aline Lara Fernandes Alonso 21 January 2014 (has links)
Neste trabalho foram analisados sedimentos marinhos de três praias da Baía de Guanabara (praia de São Bento e praia da Bica, na Ilha do Governador, e praia de São Francisco, em Niterói), Rio de Janeiro, para avaliar a presença de microplásticos (fragmentos plásticos com tamanho ≤ 5 mm) nestes ambientes. Os detritos plásticos visíveis (macroplástico) foram separados dos sedimentos manualmente e pesados. Os detritos plásticos não visíveis foram separados por densidade com solução saturada de cloreto de sódio. Os fragmentos plásticos obtidos com a separação por densidade foram caracterizados por microscopia óptica para avaliar forma e superfície, e foram classificados e quantificados em função de seu tamanho. Os fragmentos microplásticos foram separados e caracterizados por espectrometria de absorção na região do infravermelho por reflexão atenuada (ATR FT IR). Os espectros obtidos foram comparados com espectros padrão de polímeros. As três praias se apresentam contaminadas com lixo macroplástico e com lixo microplástico. Na praia da Bica, foram coletados 173 fragmentos, dos quais 73% são microplásticos. Na praia de São Bento foram 81 fragmentos e na praia de São Francisco foram 73 fragmentos, dos quais 70% e 86%, respectivamente, são microplásticos. Nas três praias foram encontrados fragmentos microplásticos de poliestireno expandido. Nas praias da Bica e de São Bento foram encontrados fragmentos de polietileno; nas praias de São Bento e São Francisco foram encontrados fragmentos microplásticos de polipropileno. O descarte irregular de lixo e atividades industriais e comerciais no entorno da baía podem ser apontados como possíveis fontes contaminantes / In this study samples of sediment of three beaches of Guanabara Bay, Rio de Janeiro, (São Bento beach and Bica beach, in Ilha do Governador and São Francisco beach, in Niterói) were analyzed to investigate the contamination with microplastics (plastic fragments ≤ 5 mm). Samples of sediment were examined by naked eye to sort items of plastic debris from other materials. After separation plastic items were weighted. Non visible plastic debris were separated from sediments by density difference applying a concentrated saline NaCℓ solution. Plastic fragments picked up from supernatant were characterized by optical microscopy to analyze morphology and classified in size fractions. From sediments of Bica beach were collected 173 plastic fragments and 73% of them were microplastic. In São Bento beach were collected 81 fragments and in São Francisco beach were collected 73 fragments, from which 70% and 86%, respectively, were microplastic. The three beaches are contaminated with both microplastic and macroplastic. Microplastic fragments were characterized by ATR FT IR. Expanded polystyrene microplastic fragments were found in sediments of the three beaches. Polyethylene microplastic fragments were found in sediments of Bica and São Bento beaches and polypropylene microplastic fragments were found in sediments of São Bento and São Francisco beaches. Littering, illegal-dumping and industrial activities are possible sources of microplastic contamination of Guanabara Bay

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