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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.
41

A carcinicultura no CearÃ: principais impactos ambientais em uma fazenda no Cumbe - EstuÃrio do Rio Jaguaribe / Shrimp farming in CearÃ: main environmental impacts on a farm in Cumbria - Jaguaribebientais River Estuary.

Josà Ãsio dos Santos 25 August 2006 (has links)
A carcinicultura à uma atividade tradicional que visa à criaÃÃo de camarÃes em cativeiro. No estado do Cearà esta atividade tem um maior potencial devido à grande quantidade de Ãreas propÃcias ao seu desenvolvimento. A criaÃÃo de camarÃes em cativeiro visando a exportaÃÃo representa mais uma opÃÃo de investimento e de diversificaÃÃo da atividade industrial para o estado. Aliada as condiÃÃes ambientais favorÃveis, os mercados nacional e principalmente internacional, à carcinicultura està marcada por uma grande demanda potencial do produto que garanta a viabilidade econÃmica da produÃÃo de camarÃes em larga escala no municÃpio de Aracati. A maioria dos problemas que ocorrem na atividade do cultivo de camarÃes sÃo resultados diretos do local onde os viveiros de engorda sÃo construÃdos. A avaliaÃÃo dos impactos ambientais dos projetos de implantaÃÃo de fazendas merece especial atenÃÃo para a escolha do local de construÃÃo dos viveiros de engorda. Do ponto de vista cientÃfico, deve-se evitar a concentraÃÃo de fazendas de criaÃÃo de camarÃes e à necessÃrio que se cuide da qualidade da Ãgua e que haja monitoramento constante dos criatÃrios a fim de evitar a poluiÃÃo dos mangues e dos recursos hÃdricos. Com o adensamento das fazendas de camarÃes, comeÃam a surgir pragas que acabam demandando um uso maior de produtos quÃmicos colocando em risco o equilÃbrio ecolÃgico e social. A atividade causa fortes impactos ambientais e sÃcio-econÃmicos. O desenvolvimento desordenado da carcinicultura afeta sobretudo o ecossistema manguezal um dos mais complexos do planeta, importante na geraÃÃo e produÃÃo de vida animal e na subsistÃncia de muitas comunidades. A carcinicultura à acusada de causar severos impactos ambientais pois modifica o fluxo da marÃs, acabam com a biodiversidade, promovem alteraÃÃes no regime hÃdrico no fluxo e disponibilidade da Ãgua, contaminaÃÃo do lenÃol freÃtico, muitas vezes afetando o abastecimento humano. à imperativo que o poder pÃblico e o setor produtivo levem em consideraÃÃo um programa de manejo e mitigaÃÃo dos impactos ambientais e estabeleÃam polÃticas e prÃticas para o cultivo sustentÃvel de camarÃo marinho no estado.
42

Análise do uso e ocupação do solo no entorno do reservatório poço da cruz, Pernambuco – Brasil

LIRA, Marianny Monteiro Pereira de 29 July 2015 (has links)
Submitted by Fabio Sobreira Campos da Costa (fabio.sobreira@ufpe.br) on 2016-04-19T15:21:29Z No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DissertaçãoMariannyPPGEC certo(1).pdf: 2446303 bytes, checksum: 15187cb5e7eb517fd37160880a26eeef (MD5) / Made available in DSpace on 2016-04-19T15:21:29Z (GMT). No. of bitstreams: 2 license_rdf: 1232 bytes, checksum: 66e71c371cc565284e70f40736c94386 (MD5) DissertaçãoMariannyPPGEC certo(1).pdf: 2446303 bytes, checksum: 15187cb5e7eb517fd37160880a26eeef (MD5) Previous issue date: 2015-07-29 / CAPEs / Os processos de uso e ocupação do solo interferem diretamente na quantidade e qualidade dos corpos hídricos. A presente pesquisa buscou analisar o uso e ocupação do solo no entorno do reservatório Poço da Cruz, localizado na região semiárida do nordeste brasileiro, município de Ibimirim – PE, tendo como objetivo subsidiar o adequado planejamento ambiental da área, considerando suas potencialidades, fragilidades e restrições de uso e a ocupação do seu entorno visando à proteção da água. O reservatório vem sofrendo forte pressão e degradação antrópica. A região semi–árida caracteriza-se, principalmente, pela escassez de água, decorrente da incidência de chuvas apenas em curtos períodos de três a cinco meses por ano, irregularmente distribuídas no tempo e no espaço. Essa característica causa uma forte dependência da intervenção do homem sobre a natureza, no sentido de garantir, por meio de obras de infra-estrutura hídrica, o armazenamento de água para abastecimento humano e demais usos produtivos. Foram utilizadas técnicas de sensoriamento remoto para a identificação do uso e ocupação atual do solo e a identificação da cobertura vegetal se deu através do Índice Normalizado de Diferença de Vegetação (NDVI), sendo identificadas 5 classes distintas de usos e ocupações na Área de Preservação Permanente (APP) do entorno do reservatório, sendo que 81,21% dessa área está em desacordo com a legislação vigente. Os valores do NDVI se apresentaram entre 0,2 e 0,3 constatando ausência de vegetação densa na APP. A diminuição do espelho d’água foi identificada através de imagens de satélites comparadas entre os anos de 2008, onde o reservatório atingiu sua cota máxima e o ano de 2015. A ausência de cobertura vegetal nas margens do reservatório facilita a capacidade de transporte de sedimentos pelo escoamento superficial e aumenta a atividade erosiva, contribuindo para o assoreamento do reservatório. / Use of processes and land use directly interferes with the quantity and quality of water bodies. This research aimed to analyze the use and occupation of land around the reservoir of the Poço da Cruz, located in the semiarid region of northeastern Brazil, the city of Ibimirim - PE, with the objective of supporting proper environmental planning of the area, considering its potential, weaknesses and restrictions of use and occupation of their surroundings in order to protect the water. The reservoir has been under strong pressure and anthropogenic degradation. The semi-arid region is characterized mainly by water scarcity, due to the rainfall only in short periods of three to five months a year, irregularly distributed in time and space. This characteristic causes a strong dependence on the intervention of man over nature, to ensure, by means of works of water infrastructure, water storage for human consumption and other productive uses. Remote sensing techniques were used to identify the use and current land use and identification of vegetation cover was through the Normalized Vegetation Difference Index (NDVI), identified five distinct classes of uses and occupations in Permanent Preservation Area (APP) surrounding the reservoir, with 81.21% of this area is at odds with current legislation. NDVI values were between 0.2 and 0.3 noting the absence of dense vegetation in APP. The decrease of the water surface was identified through satellite images compared between the years of 2008, when the reservoir reached its maximum quota and 2015. The lack of vegetation in the reservoir shores facilitates the sedimentcarrying capacity by runoff and increases the erosive activity, contributing to the silting of the reservoir.
43

Gestão ambiental em instituições de ensino superior : o caso da Universidade Federal do Acre

Ferreira, Anajara Rodrigues January 2018 (has links)
A gravidade dos problemas ambientais exige o engajamento de vários setores da sociedade, principalmente, o da educação. As instituições de ensino superior devem atuar como protagonistas no combate aos impactos ambientais gerados pela sociedade. Desta forma, o presente estudo tem por objetivo analisar a presença da gestão ambiental nas estruturas curriculares dos cursos de graduação, nas ações de extensão desenvolvidas, nos projetos de pesquisa e nas atividades operacionais realizadas no campus Rio Branco da Universidade Federal do Acre (UFAC), uma instituição de ensino superior localizada na região Norte do Brasil. Para atingir este objetivo, foram realizadas entrevistas semiestruturadas com dirigentes da IES, análise de documentos oficiais da instituição e observação assistemática nas dependências do campus. Esta análise também permitiu identificar os aspectos e impactos ambientais decorrentes das atividades desenvolvidas nos seguintes setores do campus: restaurante universitário, salas de aula e de atendimento administrativo, banheiros e laboratórios. Analisadas as condições vigentes, foram propostas ações visando a redução dos impactos ambientais identificados. Os dados coletados, analisados por meio da técnica de análise de conteúdo, identificaram que, dos 33 cursos de graduação oferecidos pela UFAC, 75,76% deles apresentam alguma disciplina na sua estrutura curricular que aborda a temática ambiental Por outro lado, foram identificadas poucas ações de extensão e poucos projetos de pesquisa relacionados as questões ambientais do campus. Em 2017, entre as atividades operacionais, havia apenas uma ação institucionalizada de gestão ambiental, que se relacionava a distribuição de garrafas para substituir o uso dos copos descartáveis, ação que desde seu início não teve descontinuidade. A UFAC possui um Plano de Gestão de Logística Sustentável, porém ainda não foi aprovado e não foi iniciada a sua execução. Observou-se que, por falta de conhecimento dos dirigentes e de sensibilização de toda a comunidade universitária, a gestão ambiental na UFAC encontra-se em um estágio inicial, o que demonstra a importância da implantação de uma ferramenta que sistematize as ações de gestão ambiental envolvendo todo o campus, buscando reduzir os impactos ambientais gerados, evitar o desperdício de recursos e tornar esta IES um exemplo para a região Norte. / The seriousness of environmental problems requires the engagement of various sectors of society, especially education. Higher education institutions should act as protagonists in combating the environmental impacts generated by society. Thereby, the present study aims to analyze the presence of environmental management in the curricular structures of undergraduate courses, in the extension actions developed, in the research projects and in the operational activities carried out at the Rio Branco campus of the Federal University of Acre (UFAC), a higher education institution located in the northern region of Brazil. To achieve this objective, semi-structured interviews were conducted with HEI leaders, analysis of official institution documents and non-systematic observation on campus premises. This analysis also allowed to identify environmental aspects and impacts resulting from the activities carried out in the following sectors of the campus: university restaurant, classrooms and administrative service, restrooms and laboratories. Analyzed the current conditions, actions were proposed to reduce the identified environmental impacts. The data collected, analyzed through the content analysis technique, identified that of the 33 undergraduate courses offered by UFAC, 75.76% of them present some discipline in their curricular structure that addresses the environmental theme On the other hand, few extension actions and few research projects related to campus environmental issues were identified. In 2017, among the operational activities, there was only one institutionalized action of environmental management, which is related to the distribution of bottles to replace the use of disposable cups, an action that from the beginning did not have discontinuity. UFAC has a Sustainable Logistics Management Plan, but it has not been approved yet and its execution has not been initiated. It was observed that, due to the lack of knowledge of the leaders and the awareness of the entire university community, environmental management at UFAC is at an early stage, which demonstrates the importance of the implementation of a tool that systematizes environmental management actions involving the entire campus, seeking to reduce the environmental impacts generated, avoid wasting resources and make this HEI an example for the Northern region.
44

Developing a Framework to Assess the Impacts of Human Health on the Environment Within the Context of COVID-19 as a Global Natural Experiment

Brandt, Kayla January 2021 (has links)
Thesis advisor: Jonathan Krones / The manifold effects of the COVID-19 pandemic include many changes to humanity's impact on the natural environment, including reduced greenhouse gas emissions from air travel and increased personal protective equipment (PPE) waste generation. The pandemic has served as a global natural experiment, revealing interactions between human health and the environment that were not clearly observable before. This research aims to develop a framework for systematically assessing the impacts of human health on the environment. This framework has been structured and populated from a review of the emerging literature on the documented environmental effects of the pandemic in addition to existing literature on environmental impacts of the health care sector in general. The framework tool catalogs observed and expected environmental effects in five stages of a public health crisis (the health issue, the medical response, the public health response, adaptation and rebound, and long-term effects) and five environmental impact categories (water pollution, solid waste, air pollution, global warming, and environmental degradation). The applicability of this framework is examined using two case studies: the 2003 SARS outbreak and the localized experience of COVID-19 in New York City. The application revealed that the framework is both transferable and scalable for use in assessing other human health crises. Overall, many of the beneficial environmental impacts that occurred as a result of the COVID-19 pandemic only came at the expense of widespread human suffering, and over time, many of these benefits were reversed. The goal is that this tool will be useful to understanding both the ways COVID-19 will continue to affect the environment as well as the effects of potential public health campaigns and crises in the future. / Thesis (BA) — Boston College, 2021. / Submitted to: Boston College. College of Arts and Sciences. / Discipline: Departmental Honors. / Discipline: Environmental Studies.
45

Global Scenarios of Metal Mining, Environmental Repercussions, Public Policies, and Sustainability: A Review

Pokhrel, Lok R., Dubey, Brajesh 01 January 2013 (has links)
With rising valuation of mineral commodities, mining has been envisioned as a profitable industry regardless of many challenges it entails. This comprehensive review provides the state of knowledge about several aspects of the metal mining industry, including (a) the basic mining processes with reasons for mine closure, (b) the potential environmental and human health impacts associated with mining, (c) the potential techniques for impact mitigation, (d) the latest production statistics for the base and precious metals with identification of currently operational major metal mines for different countries, and (e) how mining activities are regulated in different nations. Finally, the authors provide critical appraisal on the debatable issue of mining and sustainability to stimulate thoughts on how metal mining can be made sustainable, and suggest a path forward.
46

Global Scenarios of Metal Mining, Environmental Repercussions, Public Policies, and Sustainability: A Review

Pokhrel, Lok R., Dubey, Brajesh 01 January 2013 (has links)
With rising valuation of mineral commodities, mining has been envisioned as a profitable industry regardless of many challenges it entails. This comprehensive review provides the state of knowledge about several aspects of the metal mining industry, including (a) the basic mining processes with reasons for mine closure, (b) the potential environmental and human health impacts associated with mining, (c) the potential techniques for impact mitigation, (d) the latest production statistics for the base and precious metals with identification of currently operational major metal mines for different countries, and (e) how mining activities are regulated in different nations. Finally, the authors provide critical appraisal on the debatable issue of mining and sustainability to stimulate thoughts on how metal mining can be made sustainable, and suggest a path forward.
47

Resource Analysis of Small-diameter Tree Above-ground Biomass in Mississippi

Tiruveedhula, Mohan P 30 April 2011 (has links) (PDF)
Small diameter trees refer to the trees with diameter at breast height (DBH) ranging from 5 to 11 inches. This research focuses on the resource analysis and spatial distribution of small-diameter tree (SDT) volume in Mississippi by a set of grouping variables including DBH class, species, stand size, forest cover type, ownership, and county groups. Regression and spatial interpolation techniques were used to predict the SDT volume for pine, hardwood, and mixed forest covers. Regression analysis resulted in a low regression coefficient (R2) without inventory data for all the forest cover types. The mean SDT volume to the total volume was greatest for pine (0.6), followed by mixed (0.4), and hardwood (0.3) forest cover. Non-spatial estimates indicated the total volume within respective groups. The spatial and non-spatial estimates of SDT resources can guide forest management personnel to effectively focus their management efforts.
48

Protocols for the Assessment of Economic and Environmental Effects of Integrated Pest Management Programs

Beddow, Jason Michael 04 October 2000 (has links)
State Integrated Pest Management (IPM) programs are often called on to demonstrate their impacts. While many studies demonstrate techniques for assessing various economic and environmental effects of IPM, the literature provides little guidance on incorporating the techniques to perform complete assessments of IPM programs. This thesis begins with a discussion of relevant economic and environmental techniques for IPM impact assessment. Next, impact assessment techniques that are widely accepted and analytically feasible are identified. These techniques are incorporated into comprehensive impact assessment frameworks for use by individuals charged with the assessment of state level IPM programs. The study concludes with case studies which show how the assessment protocols were applied to estimate and describe the impacts of the Pennsylvania and Massachusetts sweet corn IPM programs. / Master of Science
49

Diagnóstico dos impactos socioambientais urbanos em Itacaré (BA) / Diagnosis of urban environmental and social impacts on Itacare (Bahia)

Ferreira, Paula Fabyanne Marques, 1978- 10 June 2011 (has links)
Orientador: Lindon Fonseca Matias / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-19T10:53:15Z (GMT). No. of bitstreams: 1 Ferreira_PaulaFabyanneMarques_M.pdf: 9800598 bytes, checksum: 2c254d2a94d8c5a83bcc51c72bc125d0 (MD5) Previous issue date: 2011 / Resumo: Este trabalho visa contribuir com o conhecimento sobre a dinâmica de produção do espaço geográfico na cidade de Itacaré, localizada na região cacaueira do estado da Bahia, Brasil. A emergência da cidade como polo turístico e sua perspectiva de desenvolvimento econômico tem ampliado a atratividade local e, por conseguinte, a pressão demográfica. A crescente urbanização, a especulação imobiliária, a falta de planejamento e o intenso fluxo de turistas têm desencadeado processos que afetam toda a relação entre a sociedade e o espaço natural, causando uma série de impactos socioambientais. A metodologia teve como principal estratégia a espacialização dos principais impactos, considerando as características físicas e sociais da área em estudo. Além do levantamento e revisão bibliográfica, foram realizadas visitas em campo, coleta de informações em órgãos oficiais, realização de mapeamentos temáticos, entrevistas com moradores locais, turistas e representantes públicos, análise de imagens de satélite da área de estudo e elaboração da base de dados georreferenciados, enfocando os principais impactos socioambientais urbanos. O presente diagnóstico adverte uma situação de expansão urbana voltada para o turismo sem um planejamento estratégico, que está gerando crescentes impactos socioambientais e a degradação da qualidade de vida local, especialmente dos segmentos mais pobres da população / Abstract: This paper intends to contribute to knowledge about the dynamics of production of geographical space in the town of Itacare, located in the cocoa region of Bahia, Brazil. The emergence of the city as a tourist hub and its outlook for economic development has increased the local attraction and, consequently, the demographic pressure. Increasing urbanization, real state speculation and massive flow of tourists have unleashed processes that affect the entire relationship between society and the natural space, causing a series of socio-environmental impacts. The methodology had as the most strategy, the spatialization and integration of these socio-environmental attributes, considering the physical and social characteristics of the study area. In addition to the survey and literature review, visits were made in the field, collecting information in official establishments, conducting thematic mapping, interviews with local residents, tourists and government officials, analysis of satellite images of the study area and development of georeferenced database, focusing on the major urban socio-environmental impacts. This diagnostic warns a situation of urban sprawl devoted to tourism, without a strategic planning are causing socio-environmental impacts and degradation of quality of local life, especially for the poorest segments of the population / Mestrado / Análise Ambiental e Dinâmica Territorial / Mestre em Geografia
50

The behaviour of radiocaesium in woodland ecosystems : measurement and modelling

Toal, Mark January 1999 (has links)
No description available.

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