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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.
21

Environmental Quality Assessment of Georges Bank for Atlantic cod (Gadus morhua)

Sellers, Ana M. 28 April 2003 (has links)
The Georges Bank area in the northwest Atlantic Ocean plays an important role in New England's economy. Overfishing has led to a rapid decrease in cod population numbers, leading to a collapse in certain stocks. Currently, the rate of decrease in cod numbers has slowed; however, population numbers are still low. In this study, I use Growth Rate Potential (GRP) to assess the current environmental quality of Georges Bank and its suitability to support a cod population. GRP is the amount of growth predicted for a fish with known prey availability and environmental conditions. With prey availability and temperature data obtained during the fall fisheries acoustics surveys in 2000, 2001 and 2002, I developed spatially explicit GRP maps, using bioenergetic and foraging models, for Atlantic cod to determine the ability of the Georges Bank environment to support a cod population. Results show that Georges Bank is able to support growth for adult Atlantic cod. In addition to GRP analysis, I studied nucleic acid concentrations of Atlantic herring. Nucleic acids play an important role in growth and development, and have been used to assess physical condition of fish as well as and current growth rates. In this study, I determine total nucleic acid concentrations of Atlantic herring caught during three different spawning stages: pre-, post-, and non-spawning, to determine how nucleic acid concentrations and energy allocation vary seasonally. Results support the hypothesis that nucleic acid concentrations can be used as condition indicators, and are highly sensitive to the spawning stage of fish showing a significant difference between the three groups, which may affect their ability as condition indicators.
22

Avaliação da qualidade ambiental em uma bacia hidrográfica com vocação agropecuária /

Zambon, Clezi Conforto. January 2013 (has links)
Orientador: Paulo Cesar Lodi / Banca: Jorge Hamada / Banca: Moises Teodoro Messi / Resumo: Este trabalho apresenta o levantamento e discussões dos resultados obtidos na avaliação da qualidade ambiental da bacia hidrográfica do rio Dourado. A bacia em estudo tem o rio Dourado como afluente do rio Tietê e está localizada no Centro Oeste Paulista, região de vocação agrícola, além de atividades pecuniárias e turísticas. Os principais avaliados foram: a qualidade de água, uso e ocupação do solo em torno da bacia e seu perfil sanitário. Para tanto, foram selecionados 42 (quarenta e dois) pontos de amostragens, sendo 06 (seis) no corpo principal do rio Dourado e 36 (trinta e seis) na confluência com os principais contribuintes (tributários). os parâmetros que apresentaram desconformidades foram: DBO5, Ferro Total, Cobre, Oxigênio dissolvido, Coliformes termotolerantes e condutividade elétrica, com maior evidência a partir do Ponto Tangará no sentido nascente - foz. Isto se dá devido aos diversos usos antrópicos, tanto rural quanto urbano. A forte presença do cultivo da cana-de-açúcar, pastagem de animais e a construção de condomínios às margens do rio Dourado, exercem contribuição na descaracterização da qualidade da água e nos múltiplos pontos de erosão e assoreamento existentes. A avaliação mostrou a necessidade do envolvimento do poder público e privado no que diz respeito à execução de ações mitigadoras / Abstract: This work presents results obtained from the evaluation of the environmental quality of Dourado river Hydrographic Basin. The Basin under study has Dourado river as a tributary of the Tietê river and is located in Paulista Midwest, a region of agricultural vocation, besides livestock and tourist activities. The main factors evaluated took into account water quality, use and land occupation around the Basin and its sanitary profile. To this end, 42 (forty-two) sampling points were selected, being 06 (six) in the main body of Dourado river and 36 (thirty-six) at confluence with the main contributors (tributaries). The parameters that showed changes were: BOD5, Total Iron, Copper, Dissolved Oxygen, Thermotolerant Califorms and Electrical Conductivity, with more evidence from Tangará Point in the fountaing-mouth way. This is due to several anthropic uses, both rural and urban. The strong presence of the sugar cane cultivation, animal grazing and condos building on the shores of Dourado river, contributes to water quality and multiple points of erosion and suilting existing. The evaluation showed the need of the public and private power involvement concerning the implementation of mitigating actions / Mestre
23

Integrated modeling of air pollution dynamics in the Southern Appalachian Mountains

Boylan, James W. 05 1900 (has links)
No description available.
24

An Evaluation of Indoor Environmental Quality and Occupant Well-Being in Three Southern Rural Manitoba School Buildings

Radwan, Ahmed 13 January 2015 (has links)
There is little empirical evidence in the literature to support industry claims about how green schools tend to have better indoor environmental quality (IEQ) than conventional ones and how teachers in green schools tend to feel better about their schools’ IEQ than those in conventional ones. There is also little empirical evidence in the literature about the impact of improved IEQ in literature about the impact of improved IEQ in schools on teachers’ well-being and their levels of satisfaction with their indoor environments. This research is based on a collaborative partnership with the Government of Manitoba Public Schools Finance Board, and three different public school divisions in Manitoba. It aims to develop and validate a comprehensive methodology to evaluate schools’ IEQ, teachers’ well-being and satisfaction with it, and the relationship between these two aspects. The research evaluated these specific aspects within a sample of three rural schools in Southern Manitoba, Canada: one middle-aged, conventional school; one new, non-green school; and one new, green school certified using the Leadership in Energy and Environmental Design (LEED) Rating System. The methodology developed in this thesis employs three main data collection techniques: 1) field measurements using an existing mobile instrument cart to capture environmental indicators of thermal comfort, indoor air quality, lighting quality and acoustics quality in classrooms, 2) a field observation form to record the physical conditions of the evaluated classrooms, and 3) an occupant survey to evaluate teachers’ satisfaction with their classrooms’ IEQ.
25

Leadership development : an assessment of the Aspiring Leaders Program at the Texas Commission on Environmental Quality /

Gradney, James. January 2008 (has links)
Thesis (M. P. A.)--Texas State University-San Marcos, 2008. / "Spring 2008." Includes bibliographical references (leaves 66-69).
26

A study of the system of the Annual Assessment of Urban Environmental Quality in China

Leung, Kai-fai, Edward. January 2005 (has links)
Thesis (M. A.)--University of Hong Kong, 2005. / Title proper from title frame. Also available in printed format.
27

Length of residency and the importance of environmental amenities to residential location decisions /

Walker, Judith Ellen, January 2006 (has links) (PDF)
Thesis (M.S.) in Resource Economics and Policy--University of Maine, 2006. / Includes vita. Includes bibliographical references (leaves 91-95).
28

Length of Residency and the Importance of Environmental Amenities to Residential Location Decisions

Walker, Judith Ellen January 2006 (has links) (PDF)
No description available.
29

Fragilidade ambiental e qualidade dos solos em duas bacias hidrográficas de uso rural, em Ibiúna, SP /

Manfré, Luiz Augusto. January 2011 (has links)
Orientador: Alexandre Marco da Silva / Banca: Silvio Frosini de Barros Ferraz / Banca: Fabiano Tomazini da Conceição / Resumo: A atividade agrícola tem consequências diretas sobre a qualidade do solo e dos corpos d'água. Desta forma, avaliar os impactos ambientais desta atividade econômica imprescindível, por meio de análises de solo, estudos de fragilidade ambiental e avaliação do comportamento dos produtores, é essencial para a proposição de alternativas. O objetivo do presente trabalho foi efetuar uma análise comparativa da qualidade do solo, fragilidade ambiental e do comportamento dos produtores rurais de duas bacias hidrográficas com diferentes manejos de solo, no município de Ibiúna (SP). Os estudos de fragilidade ambiental foram realizados de maneira empírica por mieo dos métodos propostos por Ross (1994) e Crepani et. al. (1996). Foram analisados atributos físicos e químicos dos solos, de maneira a comparar as diferenças entre os distintos usos de solo identificados nas bacias hidrográficas sobretudo entre as formas de cultivo orgânico e convencional. Além disso, com os atributos de solo foram desenvolvidas funções de pedotransferência e foi possível verificar a exatidão dos modelos de fragilidade ambiental estudados. Por sua vez, a análise socioambiental dos produtores foi realizada por meio de questionários e depoimentos. Os resultados das análises de solo apontaram grande semelhança entre os cultivos orgânico e convencional, não havendo distinção estatística. No entanto, o cultivo orgânico apresentou maior similaridade com os solos de vegetação quanto ao percentual de carbono e nitrogênio, se comparado aos solos de cultivo convencional. Os modelos de fragilidade ambiental resultaram em três mapas muito distintos, sendo que, o modelo com apoio nas classes de declividade obteve melhor coeficiente de correlação de Pearson com os atributos de solo. Os mapas de fragilidade foram subsídios importante para a elaboração de mapas de orientação para uso adequado... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Agricultural activity has direct consequences over soil and water quality. Thus, evaluating the environmental impacts of this important economic activity, via soil quality evaluation, environmental fragility models and behavior of human population, are essential for the elaboration of alternatives. The aim of this work was to analyze, in a comparative way, the soil quality, the environmental fragility and the behavior of the rural population, in two watersheds, within the municipality of Ibiúna (SP). The environmental fragility was executed by the empiric methods purposed by Ross (1994) and Crepani et al. (1996). Physical and chemical soil attributes were analyzed, aiming to compare the between the distinct land covers identified in the water basins, mainly the organic and the conventional cultivation. Pedotransfer functions were developed using the soil attributes and also were used to evaluate the accuracy of the fragility models. Socio-economic analysis of the population was performed by a quiz. The soil analysis results presented no statistical different between the organic and conventional cultivation soils. However, the organic cultivation soils showed higher cluster to the vegetation soils, than the results presented by the conventional cultivation soils. The fragility models resulted in three different maps, and the declivity class based model presented the best Pearson correlation coefficient. The fragility maps were used to create maps in order to generate maps to guide the soil use and the recovery areas priority. We observed important differences in the environmental degradation stages between the two river basin has a less developed process. Important pedotranfer functions were obtained, estimating the carbon and nitrogen percentage using some chemical and physical attibutes. Therefore, this work has provided important results and has generated tools... (Complete abstract click electronic access below) / Mestre
30

Aplicação da análise dimensional em indicadores ambientais de áreas degradadas pela exploração de cassiterita /

Fengler, Felipe Hashimoto. January 2018 (has links)
Orientador: Admilson Irio Ribeiro / Resumo: No contexto do desenvolvimento sustentável há um paradigma crítico, que retrata a relação entre o capital e a degradação ambiental. Conforme aumenta o cunho socioeconômico de determinada atividade, maior é a permissibilidade da sociedade aos seus efeitos ambientais negativos, sobretudo quando são apenas sentidos em nível local. Porém, após um passado de exemplos adversos, a meta por um estado de equilíbrio tem adquiro notoriedade em busca de uma nova perspectiva de desenvolvimento. Quando atividades de grande relevância, como a mineração, resultam em elevado grau de alteração do meio, há expectativa da sociedade quanto à mitigação ou compensação dos seus efeitos negativos, principalmente quando ecossistemas sensíveis são afetados. Porém, a complexidade ambiental dificulta a mensuração da extensão dos danos ambientais, bem como a efetividade de ações de recuperação. Nesse contexto se insere o presente estudo. Buscaram-se métricas e métodos compreensivos para a avaliação de florestas em recuperação em áreas minerarias na Amazônia brasileira. A técnica de modelagem com Análise Dimensional foi empregada de maneira a estabelecer índices adimensionais voltados à avaliação desses ambientes. Variáveis relacionadas ao desenvolvimento florestal, fauna, além das condições físicas, químicas e bioquímicas do solo foram empregadas, utilizando a priori o processo de conhecimento por descoberta em banco de dados em sua seleção. Dois estudos preliminares a Análise Dimensional foram realizados... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: There is a critical paradigm that portrays the sustainable development, the relationship between the capital and the environmental degradation. As the socioeconomic importance of a given activity increases, the greater will be the permissibility of society to its negative impacts, especially when they are only sensed at the local level. However, after several adverse examples in history, the aim for a state of equilibrium has acquired notoriety for a new perspective of development. When an activity of great relevance, as mining, results in high environmental alteration, there is an expectation of mitigation, or compensation, on its negative effects, especially when vulnerable ecosystems were affected. However, the environmental complexity not always allows a full comprehension of environmental damage, as well as the effectiveness of recovery actions in their reversal. This study aimed to search for comprehensive metrics and methods to evaluate of mined forests of Brazilian Amazonia. Dimensional Analysis was employed in establishing dimensionless index related to the environmental quality of the mined forests. Variables of forest development, fauna, and physical, chemical and biochemical conditions of the soil were employed, based on knowledge discovery in databases in its selection. Two preliminary studies to Dimensional Analysis were carried out, supporting the choice of variables and the further understanding about obtained dimensionless index. As a result, a methodological... (Complete abstract click electronic access below) / Doutor

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