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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

The impact of climate change on the small island developing states of the Caribbean

Maharaj, Shobha S. January 2011 (has links)
Small Island Developing States (SIDS) of the Caribbean are one of the world’s ‘hottest’ ‘biodiversity hotspots’. However, this biodiversity continues to be threatened by habitat loss, and now, by climate change. The research reported here investigated the potential of species distribution modelling (SDM) as a plant conservation tool within Caribbean SIDS, using Trinidad as a case study. Prior to the application of SDM, ancillary analyses including: (i) quantification and mapping of forest cover change (1969 to 2007) and deforestation rates, and (ii) assessment of the island’s vegetation community distribution and associated drivers were carried out. Community distribution and commercial importance and global/regional rarity were used to generate a list of species for assessing the potential of SDM within Trinidad. Species occurrence data were used to generate species distribution models for present climate conditions within the SDM algorithm, MaxEnt. These results were assessed through expert appraisal and concurrence with results of ecological analyses. These models were used to forecast suitable species climate space forty years into an SRES A2 future. Present and future models were then combined to produce a ‘collective change map’ which showed projected areas of species’ range expansion, contraction or stability for this group of species with respect to Trinidad’s Protected Areas (PAs) network. Despite the models being indicative rather than accurate, it was concluded that species’ climate space is likely to decrease or disappear across Trinidad. Extended beyond Trinidad into the remainder of the Caribbean region, SDM may be a crucial tool in identifying which PAs within the region (and not individual islands) will facilitate future survival of given target species. Consideration of species conservation from a regional, rather than an individual island perspective, is strongly recommended for aiding the Caribbean SIDS to adapt in response to climate change.
22

Cobertura florestal e custo do tratamento de águas em bacias hidrográficas de abastecimento público: caso do manancial do município de Piracicaba. / Forest cover and the cost of water treatment in municipal watershades: the case of the Piracicaba municipal watershed.

Reis, Lúcia Vidor de Sousa 26 October 2004 (has links)
A sociedade necessita de indicadores capazes de medir a susceptibilidade ao risco de degradação de um manancial de abastecimento público. O percentual de cobertura florestal de uma bacia hidrográfica pode ser utilizado como um dos indicativos na avaliação da qualidade de um manancial de abastecimento público. O custo do tratamento de águas provenientes de bacias hidrográficas com diferentes percentuais de cobertura florestal é um componente que pode subsidiar discussões sobre a importância da cobertura florestal em mananciais de abastecimento público, como recurso ambiental a ser priorizado pelo poder público e exigido pela sociedade, tendo em vista os benefícios econômicos e de minimização de riscos à saúde humana. O trabalho determinou os custos do tratamento da água proveniente de bacias hidrográficas com diversos percentuais de cobertura florestal através da análise das características operacionais de diversas Estações de Tratamento de Água (ETAs) e suas respectivas captações. Para seis dos sete sistemas e ETAs estudadas, o custo específico com produtos químicos na ETA eleva- se com a redução do percentual de cobertura florestal da bacia de abastecimento. Não se pretendeu situar e associar a localização das áreas de cobertura florestal a outros fatores como, por exemplo, a susceptibilidade do solo à erosão ou ao percentual de área florestada situada em APP’s. Considerando-se o enfoque do trabalho sobre a qualidade de mananciais de abastecimento público e a relevância do episódio de rejeição do rio Piracicaba no ano 2000 como principal manancial de abastecimento público do município de mesmo nome, em decorrência da perda de qualidade de suas águas, dos altos custos do tratamento e da impossibilidade de garantir água de consumo humano de qualidade , o trabalho teve por objetivo também analisar as perspectivas para a qualidade das águas do rio Corumbataí, novo manancial eleito para Piracicaba. Utilizou-se como recurso a análise de dados de caracterização física das bacias e sócio-econômica dos municípios das bacias dos rios Piracicaba e Corumbataí, e da qualidade das águas dos rios Piracicaba e Corumbataí. O estudo faz uma reflexão sobre o atual arranjo de instituições públicas, suas atribuições legais e ferramentas para a aplicação de leis e implementação de ações de planejamento regional nas bacias dos rios Corumbataí e Piracicaba. / The Society needs to be able to check when a water source for public supply is about to reach a degradation level. The percentage off forest covered in the watershed can be used as one of the indicators to measure the quality of a public water source. The cost of water treatment from different water supply areas containing different percentage of soil forest cover, is a component that can be brought into discussions about the importance of the forest cover in drinking water public supply areas, as an environmental natural resource, to be prioritized by the Authorities, and mandatory by the Society, heading to both economical benefits and the human health risks minimization. This work has determined the costs of water treatment from water supply areas with different percentages of natural forest cover, analysis of all operating data of all Treatment Water Stations (ETAs), as well as their water sources. For six out of seven studied systems and ETAs, the specific cost with chemical products in one ETA increases with the reduction of the known portion of rain forest for the watershed. Certainly this study was not intended to try to associate the forest location areas to other factors, as for example, the erosion soil characteristic or to the portion of forest cover, located in riparian areas. Considering the focus of this work about the public supply of drinking water and the recent episode of the Piracicaba river rejection as the main water supply for the Region in year 2000, because of the low level quality of its water, the high treatment costs, and the impossibility to make feasible to count on it to distribute good quality water, this work had also the purpose of analyzing the perspectives for the Corumbataí river, to be elected as the main source of water supply for Piracicaba. Socio-economic of all cities along the river basins of Piracicaba and Corumbataí has been studied. Besides the organization of all administrative offices in charge with the problem, their legal functions and possible available tools to plan and to work properly, has also been analyzed.
23

Cobertura florestal e custo do tratamento de águas em bacias hidrográficas de abastecimento público: caso do manancial do município de Piracicaba. / Forest cover and the cost of water treatment in municipal watershades: the case of the Piracicaba municipal watershed.

Lúcia Vidor de Sousa Reis 26 October 2004 (has links)
A sociedade necessita de indicadores capazes de medir a susceptibilidade ao risco de degradação de um manancial de abastecimento público. O percentual de cobertura florestal de uma bacia hidrográfica pode ser utilizado como um dos indicativos na avaliação da qualidade de um manancial de abastecimento público. O custo do tratamento de águas provenientes de bacias hidrográficas com diferentes percentuais de cobertura florestal é um componente que pode subsidiar discussões sobre a importância da cobertura florestal em mananciais de abastecimento público, como recurso ambiental a ser priorizado pelo poder público e exigido pela sociedade, tendo em vista os benefícios econômicos e de minimização de riscos à saúde humana. O trabalho determinou os custos do tratamento da água proveniente de bacias hidrográficas com diversos percentuais de cobertura florestal através da análise das características operacionais de diversas Estações de Tratamento de Água (ETAs) e suas respectivas captações. Para seis dos sete sistemas e ETAs estudadas, o custo específico com produtos químicos na ETA eleva- se com a redução do percentual de cobertura florestal da bacia de abastecimento. Não se pretendeu situar e associar a localização das áreas de cobertura florestal a outros fatores como, por exemplo, a susceptibilidade do solo à erosão ou ao percentual de área florestada situada em APP’s. Considerando-se o enfoque do trabalho sobre a qualidade de mananciais de abastecimento público e a relevância do episódio de rejeição do rio Piracicaba no ano 2000 como principal manancial de abastecimento público do município de mesmo nome, em decorrência da perda de qualidade de suas águas, dos altos custos do tratamento e da impossibilidade de garantir água de consumo humano de qualidade , o trabalho teve por objetivo também analisar as perspectivas para a qualidade das águas do rio Corumbataí, novo manancial eleito para Piracicaba. Utilizou-se como recurso a análise de dados de caracterização física das bacias e sócio-econômica dos municípios das bacias dos rios Piracicaba e Corumbataí, e da qualidade das águas dos rios Piracicaba e Corumbataí. O estudo faz uma reflexão sobre o atual arranjo de instituições públicas, suas atribuições legais e ferramentas para a aplicação de leis e implementação de ações de planejamento regional nas bacias dos rios Corumbataí e Piracicaba. / The Society needs to be able to check when a water source for public supply is about to reach a degradation level. The percentage off forest covered in the watershed can be used as one of the indicators to measure the quality of a public water source. The cost of water treatment from different water supply areas containing different percentage of soil forest cover, is a component that can be brought into discussions about the importance of the forest cover in drinking water public supply areas, as an environmental natural resource, to be prioritized by the Authorities, and mandatory by the Society, heading to both economical benefits and the human health risks minimization. This work has determined the costs of water treatment from water supply areas with different percentages of natural forest cover, analysis of all operating data of all Treatment Water Stations (ETAs), as well as their water sources. For six out of seven studied systems and ETAs, the specific cost with chemical products in one ETA increases with the reduction of the known portion of rain forest for the watershed. Certainly this study was not intended to try to associate the forest location areas to other factors, as for example, the erosion soil characteristic or to the portion of forest cover, located in riparian areas. Considering the focus of this work about the public supply of drinking water and the recent episode of the Piracicaba river rejection as the main water supply for the Region in year 2000, because of the low level quality of its water, the high treatment costs, and the impossibility to make feasible to count on it to distribute good quality water, this work had also the purpose of analyzing the perspectives for the Corumbataí river, to be elected as the main source of water supply for Piracicaba. Socio-economic of all cities along the river basins of Piracicaba and Corumbataí has been studied. Besides the organization of all administrative offices in charge with the problem, their legal functions and possible available tools to plan and to work properly, has also been analyzed.
24

Effects of Land Use, Market Integration, and Poverty on Tropical Deforestation: Evidence from Forest Margins Areas in Central Sulawesi, Indonesia / Auswirkungen der Landnutzung, Marktintegration und Armut durch Abholzung im Tropenwald: Nachweis aus Waldrandgebieten in Zentral-Sulawesi, Indonesien

Reetz, Sunny W. H. 30 January 2012 (has links)
No description available.
25

Contamination en éléments traces métalliques et changements de végétation liés aux activités minières dans le massif des Vosges : approche diachronique et synchronique des impacts environnementaux / trace metal contamination and landscape changes linked to mining activities in the Voges Moutains : diachronic and synchronic approach of environmental impacts

Mariet, Anne-Lise 30 November 2016 (has links)
Depuis au moins 2000 ans, le massif des Vosges a été le siège d’activités minières qui ont conduit (i) à l’émission de particules contaminées en éléments traces métalliques (ETMs), (ii) aux dépôts de déchets miniers et sidérurgiques et (iii) à des modifications du paysage. Les ressources présentes dans ce système de moyenne montagne, et utilisées par les populations, rendent nécessaire la mesure des impacts des activités anthropiques passées sur l’écosystème forestier.Ce travail de thèse propose une approche multi-proxy couplant géochimie, palynologie et écotoxicologie. Différentes phases de dépôts en ETMs ont été retracées sur les 2000 dernières années et regroupent celles connues à l’échelle de l’hémisphère Nord et des phases plus locales. L’impact paysager des activités minières semble quant à lui réduit par rapport à ce que laissaient penser les archives historiques qui présentaient des déserts forestiers dus aux activités minières. La biodisponibilité et le risque associés au transfert des ETMs ont été évalués dans un ancien district minier de production de plomb (Pb) et d’argent grâce à une campagne de bioindication active avec un indicateur de la qualité des sols, Cantareus aspersus. Sur huit stations, quatre présentent des excès de transfert induisant un risque toxicologique élevé et comprennent deux sites archéologiques miniers et un potager communal. Le fractionnement et la spéciation du Pb permettent de montrer une pratique à risque avec l’utilisation de scories comme amendements sur le potager. La contamination du milieu en ETMs par les activités minières est ici toujours transférable aux organismes du sol et donc potentiellement dans le réseau trophique / Since at least the last two millennia, mining and smelting activities have occurred in the Vosges Mountains and conducted to (i) the emission of trace metal (TM) contaminated particles in the atmosphere, (ii) the presence of mining and smelting wastes and (iii) landscape changes. Due to the use of resources from this mountainous area by local populations, it is necessary to measure impacts of these past activities on the forested ecosystem.This PhD thesis proposes a multi-proxy approach coupling geochemistry, palynology and ecotoxicology. Several phases of TM deposits have been recorded and correspond to major phases of TM contamination known in the northern hemisphere and also local periods of mining/smelting activities. The impact of mining activities on the landscape appears to be reduced contrary to historical data that described shortage of wood due to mining activities. The bioavailability and the risk associated to TMs from mining activities have been assessed in a former lead (Pb)-silver mining district by an active bioindication campaign using Cantareus aspersus, considered as indicator of soil quality. Among the eight stations, four of them present an excess of TM transfer conducting to a high ecological risk, particularly in two archaeological mining sites but also in a kitchen garden. Lead fractionation and speciation highlight the use of slags as amendments in the kitchen garden. Trace metal contamination of the soil due to mining activities is still bioavailable for soil organisms and so potentially transferred in food chain.

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