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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

A political ecology of living aquatic resources in Lao PDR

Bush, Simon R January 2004 (has links)
Doctor of Philosophy(PhD) / This thesis uses a political ecology framework to critically analyse how development and environmental orthodoxies influence the use, management and development of living aquatic resources in an information poor developing country context. The research focuses specifically on Lao PDR, the only landlocked country of the Mekong River Basin, to question how knowledge over living aquatic resources is framed by a range of stakeholders. Specific attention is given to how aquaculture has gained ascendancy over capture fisheries in the rhetoric of resources users as well as government and nongovernment organisations. The empirical research focuses on the role of broad scale economic, social and environmental influences over resource use, the practical and perceived importance of both aquaculture and capture fisheries in rural Lao livelihoods and finally, how living aquatic resources are represented within the dominant development agendas of conservation, poverty alleviation and rural development. Field work was conducted in Savannakhet province in Southern Lao PDR over 18 months from 2001 to 2002. The thesis has a strong empirical research base divided into activities carried out over multiple scales ranging from household to the Mekong River Basin. The thesis begins by establishing the historical context of resource use as well as the major orthodoxies on which development is based. Attention then turns to the extensive empirical research conducted over three districts of Savannakhet province. The results of the empirical research report two macro scale studies at the district level. The first is a survey of fish ponds across three districts focusing on the spatial distribution of investment and resource use. The second is a survey of fish trade focusing on the differential trade between culture and capture fish species. The results of both studies highlight the disjuncture between complex patterns of aquaculture and capture fishery use and the major assumptions made about the use of these two resources by policy makers and management. Analysis then moves to the local level focusing on the role and importance of aquaculture and capture fisheries to the livelihoods of rural Lao communities. The results show the instrumental and hermeneutic importance of fish and other aquatic resources in the livelihoods of households and the community. In particular it is shown that capture fisheries are more important to rural livelihoods in terms of income and nutrition, while aquaculture is perceived as a more important activity in the development of community and household economies. ii The final section then compares the empirical findings of the thesis with the policy and planning agendas of government and non-government organisations. The analysis focuses on the role of ideas and agency creating a highly politicised policy environment concluding that aquaculture based policy is more compatible with both government and non government agendas of poverty alleviation and rural development than capture fisheries. Furthermore, capture fisheries are marginalised within conservation as a resource that cannot contribute to the improvement of livelihoods or alleviate poverty. The thesis concludes that living aquatic resources provide an imperative source of food and income to rural communities through diverse and complex human-environment interactions. In contrast government and non-government organisations operating at regional, national and local scales of policy and planning simplify these relationships drawing on wider orthodoxies of aquaculture and capture fisheries development. These simplifications do not reflect the problems and needs of the predominantly rural population. Furthermore, in the absence of a strong empirical base of information, living aquatic resources management and development has become highly politicised. Instead of responding to the realities of resource users, policy and planning reflect the interests and beliefs of development organisations, government and non-government. The thesis provides an important, grounded account of the importance of living aquatic resources to rural livelihoods in Lao PDR and how these resources are understood and translated into national development and management agendas. In doing so the thesis contributes to an understanding of how complex human-environmental systems are perceived and represented in development policy and wider knowledge systems. The thesis also makes an important theoretical contribution to the growing body of literature on critical political ecology by arguing for the revitalisation of ecology as an integrated approach within political ecology and more widely within the study of humanenvironment interaction.
2

A political ecology of living aquatic resources in Lao PDR

Bush, Simon R January 2004 (has links)
Doctor of Philosophy(PhD) / This thesis uses a political ecology framework to critically analyse how development and environmental orthodoxies influence the use, management and development of living aquatic resources in an information poor developing country context. The research focuses specifically on Lao PDR, the only landlocked country of the Mekong River Basin, to question how knowledge over living aquatic resources is framed by a range of stakeholders. Specific attention is given to how aquaculture has gained ascendancy over capture fisheries in the rhetoric of resources users as well as government and nongovernment organisations. The empirical research focuses on the role of broad scale economic, social and environmental influences over resource use, the practical and perceived importance of both aquaculture and capture fisheries in rural Lao livelihoods and finally, how living aquatic resources are represented within the dominant development agendas of conservation, poverty alleviation and rural development. Field work was conducted in Savannakhet province in Southern Lao PDR over 18 months from 2001 to 2002. The thesis has a strong empirical research base divided into activities carried out over multiple scales ranging from household to the Mekong River Basin. The thesis begins by establishing the historical context of resource use as well as the major orthodoxies on which development is based. Attention then turns to the extensive empirical research conducted over three districts of Savannakhet province. The results of the empirical research report two macro scale studies at the district level. The first is a survey of fish ponds across three districts focusing on the spatial distribution of investment and resource use. The second is a survey of fish trade focusing on the differential trade between culture and capture fish species. The results of both studies highlight the disjuncture between complex patterns of aquaculture and capture fishery use and the major assumptions made about the use of these two resources by policy makers and management. Analysis then moves to the local level focusing on the role and importance of aquaculture and capture fisheries to the livelihoods of rural Lao communities. The results show the instrumental and hermeneutic importance of fish and other aquatic resources in the livelihoods of households and the community. In particular it is shown that capture fisheries are more important to rural livelihoods in terms of income and nutrition, while aquaculture is perceived as a more important activity in the development of community and household economies. ii The final section then compares the empirical findings of the thesis with the policy and planning agendas of government and non-government organisations. The analysis focuses on the role of ideas and agency creating a highly politicised policy environment concluding that aquaculture based policy is more compatible with both government and non government agendas of poverty alleviation and rural development than capture fisheries. Furthermore, capture fisheries are marginalised within conservation as a resource that cannot contribute to the improvement of livelihoods or alleviate poverty. The thesis concludes that living aquatic resources provide an imperative source of food and income to rural communities through diverse and complex human-environment interactions. In contrast government and non-government organisations operating at regional, national and local scales of policy and planning simplify these relationships drawing on wider orthodoxies of aquaculture and capture fisheries development. These simplifications do not reflect the problems and needs of the predominantly rural population. Furthermore, in the absence of a strong empirical base of information, living aquatic resources management and development has become highly politicised. Instead of responding to the realities of resource users, policy and planning reflect the interests and beliefs of development organisations, government and non-government. The thesis provides an important, grounded account of the importance of living aquatic resources to rural livelihoods in Lao PDR and how these resources are understood and translated into national development and management agendas. In doing so the thesis contributes to an understanding of how complex human-environmental systems are perceived and represented in development policy and wider knowledge systems. The thesis also makes an important theoretical contribution to the growing body of literature on critical political ecology by arguing for the revitalisation of ecology as an integrated approach within political ecology and more widely within the study of humanenvironment interaction.
3

Schutz und Entwicklung der aquatischen Ressourcen

Naumann, Oliver, Striegl, Stefan 23 May 2011 (has links) (PDF)
In fünf Fließgewässern Sachsens wurde die Wirkung von Baumaßnahmen der Landestalsperrenverwaltung auf die Lebensbedingungen für Fische begutachtet. Bewertet wurde der Rückbau von Wehren, der Einbau von Fischaufstiegsanlagen sowie Renaturierungsmaßnahmen mit Strukturverbesserungen der Gewässersohle. Die Maßnahmen in der Triebisch, der Müglitz, der Wesenitz und der Kleinen Spree verbesserten die Lebensbedingungen und Wandermöglichkeiten für Fische. Die komplexen Baumaßnahmen in der Chemnitz inmitten des Stadtgebiets bewirkten bislang noch keine Verbesserungen.
4

Use of bioindicators and biomarkers to assess aquatic environmental contamination in selected urban wetlands in Uganda

Naigaga, Irene January 2013 (has links)
Pollution of aquatic resources in Uganda is on the increase and the trends are expected to increase with increase in population size and urbanisation. Assessment and mitigation of the environmental impacts on water quality and biodiversity have now become necessary. The aim of the study was to integrate invertebrate and fish as bioindicators and fish histopathology as a biomarker in the assessment of water quality deterioration in urban wetlands in Uganda. The integration harnesses the advantages and counteracts the shortcomings of each method and thus builds a more robust diagnostic tool that gives a better view of the impacts to the entire ecosystem. Four endpoints which included, physicochemical variables, benthic macroinvertebrate bioindicators, fish bioindicators and fish histopathology biomarkers were compared between varied effluent-impacted wetlands (Murchison Bay in Kampala, and Kirinya, Masese and Winday Bay in Jinja) and a non-impacted reference wetland (Lwanika in Mayuge). Results from the effluent-impacted sites differed from the less impacted reference site. The two sampling locations at Murchison Bay (inshore and offshore) and one sampling location at Kirinya (inshore), that were highly impacted with urban effluent, showed elevated nutrient levels, low pH, dissolved oxygen and secchi depth readings. This corresponded with low invertebrate taxa and fish species diversity and richness; and severe histopathological responses in liver, gonads and gills of O. niloticus. Sensitive taxa such as ephemeroptera and trichoptera were completely absent while pollution tolerant taxa Chironomus sp, Corbicula and Oligochaeta were present. Also notable was the absence of many native haplochromines and presence of mainly Brycinus sadleri, Oreochromis niloticus and leucostictus. The organs manifested high prevalence of severe inflammatory and regressive changes and higher organ indices that fell within the pathological category. These sites were consistently classified as highly polluted under the four endpoints. The reference site was classified as least polluted while Masese and Winday Bay were moderately polluted. Results suggested that the approach of using invertebrate and fish as bioindicators and the fish histopathology as a biomarker, in relation to water quality physicochemical variables was a useful tool in highlighting the spatial differences in environmental quality.
5

Jaws of significance: the conservationist's perception of the shark in South Florida

Unknown Date (has links)
In examining the intentional relationship between the conservationist and the shark in South Florida, this thesis considers the latter as both a scarce natural resource - caught up in what Clifford Geertz citing Weber referred to as "webs of significance" (Geertz 1973:5) - and as a reflection of dynamic human conceptions of nature : a meta shark. This complex relationship is described by interpretations of conservation discourse recorded through ethnographic interviews that demonstrate how these perceptions have been influenced by factors such as personal experiences, film and text, and broad changes in the relationship between humans and nature since the early days of the environmental movement. By linking these perceptual changes with changes in American shark conservation policy, this work not only explains a relationship between culture, perception, and policy, but also celebrates the emergence of a multispecies marine community. / by Patrick Nason. / Thesis (M.A.)--Florida Atlantic University, 2012. / Includes bibliography. / Mode of access: World Wide Web. / System requirements: Adobe Reader.
6

Schutz und Entwicklung der aquatischen Ressourcen

Naumann, Oliver, Striegl, Stefan 23 May 2011 (has links)
In fünf Fließgewässern Sachsens wurde die Wirkung von Baumaßnahmen der Landestalsperrenverwaltung auf die Lebensbedingungen für Fische begutachtet. Bewertet wurde der Rückbau von Wehren, der Einbau von Fischaufstiegsanlagen sowie Renaturierungsmaßnahmen mit Strukturverbesserungen der Gewässersohle. Die Maßnahmen in der Triebisch, der Müglitz, der Wesenitz und der Kleinen Spree verbesserten die Lebensbedingungen und Wandermöglichkeiten für Fische. Die komplexen Baumaßnahmen in der Chemnitz inmitten des Stadtgebiets bewirkten bislang noch keine Verbesserungen.
7

Cooking fish and drinking milk? Patterns in pottery use in the southeastern Baltic, 3300–2400 cal BC

Heron, Carl P., Craig, O.E., Luquin, A., Steele, Valerie J., Thompson, A., Piličlauskas, G. 05 August 2015 (has links)
Yes / A study of pottery vessel contents and use was undertaken in order to obtain information on food processed in Subneolithic and Neolithic vessels from Nida and Šventoji (3300–2400 cal BC). The aim is to assess pottery use during major changes in the coastal environment and in material culture. Bulk carbon and nitrogen isotope, lipid biomarker and compound specific carbon isotope analysis was undertaken on ‘foodcrusts’, charred deposits adhering to vessel surfaces, and absorbed residues from different vessel types. In addition, three archaeological seal bones were analysed for bulk collagen and compound specific carbon isotope analysis to establish collagen-lipid offsets to inform interpretation of the data. The results show that the majority of the vessels were used for processing aquatic products. At Nida the data suggest exploitation of freshwater resources and, in the later stages of occupation, dairying. Analysis of a small number of Subneolithic vessels from Šventoji produced results that are also consistent with processing of aquatic products. Other substances identified include Pinaceae sp. resin or tar and beeswax. These data demonstrate that identifying patterns in pottery use contributes to understanding Neolithisation processes.
8

Optimal management of renewable resources a dynamic model of surface water contamination from pesticide use in rice production in the Mekong Delta, Vietnam /

Dang, Phuong M. January 2002 (has links)
Thesis (Ph. D.)--University of Hawaii at Manoa, 2002. / Includes bibliographical references (leaves 113-116).
9

RELAÇÃO DE BENEFÍCIO - CUSTO AMBIENTAL DOS SISTEMAS DE ÁGUA E ESGOTO SANITÁRIO: ESTUDO DE CASO, CANOAS RS / AMBIENTAL BENEFIT-COST RELATIONSHIP OF WATER AND SANITARY SEWERAGE SYSTEMS CASE STUDY: CANOAS RS

Miola, Alessandro Carvalho 28 April 2005 (has links)
Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This case study was carried out at Canoas a city in the State of Rio Grande do Sul - Brazil, involving sanitation problems, mainly those related to the sanitary sewer thrown directly in the rivers and streams without any previous treatment. The sanitary service in Canoas is made by CORSAN (Companhia Riograndense de Saneamento). The company has a contract ending in 2025. However, the company is not accomplishing the goals, as was accorded between CORSAN and the City Hall. The objective of this study is to analyze the relation benefit-cost of the sanitary system in Canoas, with respect to the environmental and economic-financial aspects. Canoas has an important position in respect to the ambient because is geographically located downstream of hydrographic basins of the rivers Sinos, Gravataí and Jacuí. This last one having in its estuary the State Park of the Delta of the Jacuí, that is part of the Hydrographic Region of the Guaíba. More than 90% of the population has no access to the sanitary sewerage system. The residents do their own sanitary sewer connections directly into the pluvial drain that drives the water to the macro drainage system to the rivers and streams, impact and contaminating the environment. A station of sewerage treatment (ETE) is installed in the city and should have the capacity to treat 1.300 liters of sewer per second, however only one of the six projected modules is actually working, with less than 20% of its capacity. Practically collection nets don't exist, though the net of water has more than 795 km of extension. Regarding to the water supply, CORSAN capture water in two places, one at the city of Esteio. The main point of impounding of water is located in the Arroio das Garças (Stream of the Herons), downstream of the tributaries that lead the sewer, without treatment, through the macro-drain system until the stream. Between they, the estuary of the Arroio Araçá (Stream of the Araçá), launching greater of sewer without treatment, it is the 650 meters of distance of the capitation. In the economic-financial aspect the profit of approximately 24 million of Reais per year that Corsan earns in Canoas is drained to supply administrative expenses itself of the company and to cover the systems deficit of other cities by the method called Crossed Subsidy. Being thus, the population, paid for a precarious attention, inefficient and it supports the operation of the CORSAN in other cities. It has, in the Region Metropolitan of Porto Alegre, a process of pollution of the aquatic resources that must be eliminated, in short time; therefore they are aggravated and they grown, daily, the problems of the public health and the deterioration of the environment cam be come irreversible. / Este estudo de caso foi realizado no Município de Canoas RS abordando o problema do saneamento, principalmente em relação ao lançamento dos esgotos sanitários, feito sem tratamento prévio, diretamente nos rios e arroios da região. Tal serviço, em Canoas, é concedido à Companhia Riograndense de Saneamento (CORSAN), cujo contrato estende-se até 2025; porém, a mesma não está cumprindo as metas ajustadas com a Prefeitura. O estudo objetivou analisar a relação de benefício-custo do sistema de saneamento, nos aspectos ambiental e econômicofinanceiro. No aspecto ambiental Canoas tem posição de destaque, pois sua localização geográfica está à jusante das sub-bacias hidrográficas dos rios: Sinos; Gravataí; e Jacuí. Este último tendo na sua foz o Parque Estadual do Delta do Jacuí, que faz parte da Região Hidrográfica do Guaíba. Mais de 90% da população de Canoas não possui coleta de esgoto sanitário. Os moradores fazem a ligação do esgoto sanitário diretamente na rede de drenagem pluvial, que leva a água da chuva para o sistema de macrodrenagem e deste para os rios e arroios das sub-bacias hidrográficas impactando e poluindo a ambiência. No município há uma Estação de Tratamento de Esgotos ETE, com vazão para 1.300 litros de esgoto bruto por segundo, porém apenas um dos seis módulos projetados foi construído e opera com menos de 20% de sua capacidade. Praticamente não existem redes de coleta, todavia a rede de água tem mais de 795 km de extensão. A água bruta é captada em dois locais, um deles no Município de Esteio. O principal ponto de captação está no Arroio das Garças, à jusante dos afluentes que levam o esgoto sem tratamento, através do sistema de macrodrenagem, até o arroio. Entre eles a foz do Arroio Araçá, um dos maiores lançadores de esgoto sem tratamento, está a 650 metros de distância da captação. No aspecto econômico-financeiro o ganho de aproximadamente 24 milhões de Reais por ano que a CORSAN obtém em Canoas é canalizado para suprir despesas administrativas da superestrutura da própria companhia e para atender os sistemas deficitários de outras cidades pelo chamado Subsídio Cruzado. Assim, a população de Canoas paga por um atendimento precário, ineficiente e sustenta a operação da CORSAN em outras cidades. Há na Região Metropolitana de Porto Alegre um processo de poluição dos recursos hídricos que deve ser combatido em curto prazo, pois se agravam e crescem, diariamente, os problemas na saúde pública e a deterioração da ambiência pode se tornar irreversível.
10

Revitaliza??o do Rio Golandim (RN/Brasil) ap?s d?cadas de contamina??o por efluentes industriais e dom?sticos: este rio est? recuperado?

Costa, Aline Rocha de Paiva 31 May 2012 (has links)
Made available in DSpace on 2014-12-17T15:55:00Z (GMT). No. of bitstreams: 1 AlineRPC_DISSERT.pdf: 3018551 bytes, checksum: 17363a397c49ea615dc8b9fbdbe31f5c (MD5) Previous issue date: 2012-05-31 / Environmental pollution causes the loss of the quality of aquatic resources and also affects the health of human beings. The Golandim River is located in S?o Gon?alo do Amarante (RN Brazil) and had its water recovered seven years ago by measurements of parameters of the water s quality analyses physicochemistry, microbiological and heavy metals. However, it is not well established if this river is truly recovered, so this study provides a wide knowledge about the quality of these waters. Therefore, this investigation was accomplished by assays of ecotoxicology utilizing Ceriodaphnia dubia and of genotoxicity of the river s water using a biomarker Tradescantia Pallida (Trad-MCN). In set, it carried through a study of environmental perception through questionnaires that approached questions related to the profile of the interviewed one, knowledge on the environment and of the river Golandim with the community that lives in the neighborhoods of the river to diagnosis as they perceive the environment where live and its problems. The assays of the water had been carried out by collecting samples in three different sites of the Golandim River. They were collected between the periods of December 2010 (dry season in the northeast of Brazil) and July 2011 (rainy season in the northeast of). The analysis of the data allowed observing that the majority of the inhabitants are adult and presents a global vision of what it is part of the environment, the majority mentions the pollution of the river as one of the problems of the city, considering it serious. The ecotoxicology assay showed that there was not acute toxicity in all three samples collected. Meanwhile, all these three samples demonstrated significant chronic toxicity. The results from the Trad-MCN assay presented an increase in the frequency of micronucleus in one of the sites analyzed (S3) (p<0.01), in both seasons collected. On the other hand, the sites S1 and S2 did not presented a significant increase of micronucleus using this bioassay. The analyses of chemicals detected an increase in the levels of some metals, in different seasons and samples, which can be associates with some compounds found in urban and industrial areas. On the other hand, the physicochemistries parameters demonstrated that the Golandim River is recouped, when compared with the values presented at the CONAMA s legislation. However, these results indicate the presence of compounds capable of inducing chromosomal mutation in plants. On the other hand, the parameters physicistchemistries demonstrate that the river Golandim is if recouping, since when compares the values observed with the legislation of the CONAMA. All these results point to the fact that the Trad-MCN assay was sensitive and efficient biomarker for chromosomal instability and the C. dubia ecotoxicology assay was as though an efficient biomarker of toxicity of water s quality. The results from Trad-MCN associated with the ecotoxicology demonstrates that these analyses are important for environmental monitoring, once the first bioassay described above indicates alterations at the standards of cells and the other one indicates alterations at the standards of organisms. This study alerts for the necessity to carry out biological assays for the analyses of the water s quality / A ?gua ? essencial para a manuten??o da vida, entretanto, a polui??o ambiental vem causando a perda da qualidade dos recursos h?dricos, afetando assim a sa?de humana. Este estudo avaliou a qualidade da ?gua do Rio Golandim no munic?pio de S?o Gon?alo do Amarante/RN/Brasil ap?s a realiza??o do plano de recupera??o atrav?s de medi??es de par?metros de qualidade de ?gua - an?lises f?sico-qu?micas, de metais pesados e microbiol?gicos al?m de incluir ensaio de ecotoxicidade com Daphnia dubia e teste que detecta a presen?a de compostos mutag?nicos em Tradescantia pallida (Trad-MCN). Em conjunto, foi realizado um estudo de percep??o ambiental atrav?s de question?rios que abordou quest?es relacionadas ao perfil do entrevistado, conhecimentos sobre o meio ambiente e do rio Golandim, com a comunidade que vive nas proximidades deste rio para diagnosticar como eles percebem o ambiente em que vivem e seus problemas. Os experimentos foram realizados a partir de amostras de ?gua coletadas em dezembro de 2010 (esta??o do ano seca) e em julho de 2011 (esta??o das chuvas) em tr?s pontos diferentes do rio Golandim. A an?lise dos dados de percep??o ambiental permitiu observar que a maioria dos moradores s?o adultos e apresentam uma vis?o global do que ? meio ambiente e a maioria menciona a polui??o do rio como um dos problemas do munic?pio, considerando-o grave. Os dados resultantes do ensaio ecotoxicol?gico n?o indicou efeito de toxicidade aguda, entretanto demonstrou toxicidade cr?nica para a m?dia de reprodu??o dos clad?ceros nas esta??es do ano seca e chuvosa, em todos os pontos amostrados, os resultados provenientes do ensaio Trad-MCN para a ?gua bruta mostrou resposta positiva, representada pelo aumento na frequ?ncia de micron?cleos, para um dos pontos analisados (P3) em ambas as esta??es de coleta. As an?lises qu?micas detectaram um aumento nos n?veis de alguns metais nos diferentes per?odos e amostras, que podem estar associados ainda ? presen?a de compostos de origem urbana e industrial. Contudo, os par?metros f?sico-qu?micos demonstram que o rio Golandim est? se recuperando, j? que quando se compara os valores observados com a legisla??o brasileira do CONAMA. Nossos resultados apontam para a presen?a na ?gua de compostos capazes de induzir muta??es, podendo gerar s?rios agraves ? sa?de da popula??o que utiliza e reside nas proximidades do Golandim, a qual ainda se sente insegura quanto a utiliza??o do mesmo. Desta forma, este estudo alerta para a necessidade de realizar ensaios biol?gicos al?m de empregar apenas as an?lises provenientes das medi??es f?sico-qu?micas para atestar a qualidade de um corpo d ?gua, como tamb?m da realiza??o de trabalhos de educa??o ambiental com a comunidade ribeirinha

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