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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

The ecological economics of inter-basin water transfers: the case of the Lesotho Highlands Water Project

Matete, Mampiti Elizabeth 05 June 2006 (has links)
This study developed a general framework that can be applied to integrating environmental sustainability aspects into economic development planning in the case of exploiting water resources through inter-basin water transfers (IBWT). Using the Lesotho Highlands Water Project (LHWP) between Lesotho and South Africa (SA), the study used the multi-country ecological social accounting matrix (MC-ESAM) for Lesotho and SA to integrate ecological implications of the LHWP with the economic benefits of the project. The study further used the developed MC-ESAM multipliers to analyse the impact of lost ecological services downstream the LHWP dams in Lesotho on the wellbeing of households directly affected by the project in Lesotho and the general economies of Lesotho and SA. The MC-ESAM multipliers were also used to analyse different policy scenarios aimed at compensating affected households in Lesotho for ecological losses. The results revealed that while the LHWP has significant direct and indirect benefits in terms of social and economic development in Lesotho and SA, the project has serious unitended impacts on ecological resources and services, with resultant deleterious wellbeing implications for populations residing within the reaches of the LHWP rivers and downstream the LHWP dams in Lesotho. The results from the MC-ESAM multiplier analysis indicated that not only the income of populations directly affected by the project in Lesotho is likely to fall, but also that of other households and social groups, as well as the general economies of Lesotho. Also, because of economic dependence of Lesotho on SA in terms of imports, SA will also loose. The policy simulation results showed that compensating the ecological losses would greatly improve the welfare of directly affected populations and the rest of Lesotho economy. The empirical analysis and policy simulations results showed relatively small impacts in general, but were significant for groups of people directly affected by the project in Lesotho. The study demonstrated the importance of integrating ecological consequences into impact assessment of IBWT before such transfers can be implemented to ensure Pareto optimality and of considering economy-wide impacts and multi-sector, multi-country linkages associated with IBWT for a holistic impact assessment of IBWT. / Thesis (PhD (Agricultural Economics))--University of Pretoria, 2007. / Agricultural Economics, Extension and Rural Development / unrestricted
2

A Conceptual Model OF Groundwater Flow in Spring Valley, NV, AND Snake Valley, NV-UT

Gillespie, Jeremy Micheal 07 February 2008 (has links) (PDF)
A geochemical study of major springs and wells in Spring Valley, Nevada, and Snake Valley, Utah-Nevada was initiated in response to the Clark, Lincoln and White Pine Counties Groundwater Development Project proposed by the South Nevada Water Authority (SNWA). Water budget estimates suggest that interbasin flow accounts for a significant portion (~25%) of the water budgets in Spring and Snake Valleys. Although interbasin flow is possible in some areas, alternative plausible explanations place significant uncertainty on water budget allocations. To examine the plausibility of local and interbasin flow paths the groundwater flow in Spring and Snake Valleys was evaluated using solute and isotopic data. Evidence for local flow paths includes: 1) stable isotope values in local areas which are similar to isotope values in adjacent recharge zones; 2) measurable 3H content and 14C activities ≥ 50 pmc in most samples which suggests short residence times; and 3) plausible geochemical models of local flow paths. Previously defined interbasin flow paths in southern Spring Valley are marked by samples that have low 14C activities (mean = 20.14 pmc), which are consistent with long residence times and can be explained by either interbasin flow from adjacent basins or deep circulation in the basin-fill sediments of Spring Valley. Interbasin flow from southern Spring Valley to southern Snake Valley cannot be confirmed or rejected based on the current data and modeling constraints, which result in plausible models involving both local flow paths and interbasin flow paths. Interbasin flow from northern Spring Valley to northern Snake Valley is unlikely and can be explained by the deep circulation of groundwater that is mixed with modern recharge. The plausibility of alternative explanations to describe previously defined interbasin flow paths suggests that water budget allocations in Spring and Snake Valleys should be redistributed or reevaluated. The use of existing water budgets that allocate large components of water to interbasin flow to determine the distribution of water resources may result in incorrect estimations of available resources.
3

Proposição de indicadores de segurança hídrica: seleção, validação e aplicação na bacia hidrográfica do rio Jundiaí-Mirim, Jundiaí - SP, Brasil / Proposition water security indicators: selection, validation and application in the Jundiaí-Mirim river basin, Jundiaí - SP, Brazil

Machado, Fernando Henrique 01 March 2018 (has links)
Submitted by Fernando Henrique Machado (fernandomtb@hotmail.com) on 2018-04-23T13:30:20Z No. of bitstreams: 1 FHM - Tese 132 [PD].pdf: 9073445 bytes, checksum: 558a93dca350999137782573a2b01e5b (MD5) / Rejected by Bruna Bacalgini null (bruna@sorocaba.unesp.br), reason: Prezado, Solicitamos que realize correções na submissão seguindo as orientações abaixo: O pdf não pode estar protegido, por favor, faça a submissão novamente com arquivo pdf não protegido. Agradecemos a compreensão. on 2018-04-23T14:00:52Z (GMT) / Submitted by Fernando Henrique Machado (fernandomtb@hotmail.com) on 2018-04-23T14:39:49Z No. of bitstreams: 1 FHM - Tese 132 [PD].pdf: 9054390 bytes, checksum: 858ba049e3608953cf364a4045e9e325 (MD5) / Approved for entry into archive by Bruna Bacalgini null (bruna@sorocaba.unesp.br) on 2018-04-23T14:44:42Z (GMT) No. of bitstreams: 1 machado_fh_dr_soro.pdf: 9054390 bytes, checksum: 858ba049e3608953cf364a4045e9e325 (MD5) / Made available in DSpace on 2018-04-23T14:44:42Z (GMT). No. of bitstreams: 1 machado_fh_dr_soro.pdf: 9054390 bytes, checksum: 858ba049e3608953cf364a4045e9e325 (MD5) Previous issue date: 2018-03-01 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / As bacias hidrográficas localizadas em áreas densamente ocupadas e industrializadas sofrem diferentes pressões antrópicas, situação que compromete a qualidade e quantidade da água. Esse cenário, peculiar nas bacias hidrográficas dos rios Piracicaba, Capivari e Jundiaí (BH-PCJ), reflete também na sub-bacia hidrográfica do rio Jundiaí-Mirim (BH-JM), responsável pelo fornecimento de 95% da água consumida por Jundiaí-SP. Todavia, a vazão produzida nesta bacia é insuficiente para atender as demandas do município, necessitando da reversão sazonal das águas do rio Atibaia. Diante desse quadro de estresse hídrico, este estudo visou propor e analisar um conjunto de indicadores de segurança hídrica visando a melhoria da capacidade de planejamento e gestão dos recursos hídricos da BH-JM. Assim, utilizou-se de uma abordagem metodológica pautada na seleção, validação, aplicação e estruturação de indicadores de segurança hídrica em um modelo de causa-efeito. Os indicadores foram submetidos à avaliação por meio de um painel multidisciplinar de especialistas utilizando-se o método Delphi. Os indicadores validados pelo painel foram discutidos e, posteriormente, sistematizados a fim do estabelecimento das diretrizes. Os indicadores selecionados foram: (i) oferta de água; (ii) reservatórios de água; (iii) rede de distribuição; (iv) perdas na distribuição de água potável; (v) transposição de água; (vi) qualidade físico-química e biológica da água; e (vii) políticas públicas. Os principais resultados foram: (i) a série histórica analisada apontou um crescimento populacional de 1,8% a.a., conquanto a produção de água tratada cresceu a taxas inferiores (1,2% a.a.), onde verificou-se a redução constante do consumo per capta de 248 L hab.-1 dia-1 para 203 L hab.-1 dia-1 em um período de 17 anos; (ii) as áreas ocupadas por lagos e reservatórios foram ampliadas em 703% em um período de 4 décadas, sendo a maior área representada pelo reservatório de abastecimento público, do qual estimou-se receber uma carga de sedimentos de 1,5 mil t ano-1 ; (iii) o crescimento geométrico da rede de distribuição aumentou a taxas de 3,1% a.a., refletindo no aumento linear do número de ligações ativas de água; (iv) as perdas médias do sistema de distribuição de água potável encontra-se na ordem de 34% ao longo de quase duas décadas, representando perdas de aproximadamente 17,6 milhões de m3 ano-1 ou R$ 38,3 milhões ano-1 ; (v) uso cada vez mais frequente das águas revertidas do rio Atibaia, medida que pode emergir inúmeros desdobramentos e conflitos futuros pelo uso da água na região; (vi) alterações adversas na qualidade físico-química da água da BH-JM em decorrência da transposição, como o aumento na concentração de íons metálicos, turbidez, cloreto, dentre outros; (vii) identificou-se um amplo aparato jurídico-ambiental relacionadas à BH-JM, porém com baixa eficácia jurídica em suas aplicações. Em face dos resultados, 49 diretrizes de gestão foram propostas. Desse modo, a abordagem metodológica empregada revelou-se adequada e replicável para outras bacias, uma vez que: a partir do método Delphi foi possível estabelecer critérios de seleção de indicadores considerando a problemática em análise; a discussão individual dos indicadores permitiu uma melhor compreensão das dinâmicas envolvidas em cada indicador; a estruturação dos indicadores em um modelo-causal permitiu a sistematização das informações e, consequentemente, contribuiu para o estabelecimento das diretrizes. / The river basins located in densely occupied and industrialized areas are subject to different anthropogenic pressures, a condition that compromises directly the quality and quantity of water resources. This situation is common in the Piracicaba, Capivari, and Jundiaí river basins (BH-PCJ), southwestern Brazil, as well as in the Jundiaí-Mirim river basin (BH-JM) (sub-basin of the Jundiaí river). The BH-JM is a strategic area due to supply 95% of the raw water consumed by Jundiaí-SP. However, the available water flow in this basin is not enough to meet the local demands. This fact led to the need for seasonal interbasin water transfer from the Atibaia river. In view of this water stress scenario, this study aimed to propose and analyze a set of water security indicators for improving the planning and management capacity of the BHJM water resources. Therefore, a methodological approach based in selection, validation, application and structuring of water safety indicators was used in a cause-effect model. The indicators were submitted to the assessment through a multidisciplinary panel of experts using the Delphi method. The valid indicators from the panel were well discussed and, posteriorly, systematized for purpose of establishment of guidelines. The selected indicators were: (i) water supply; (ii) water reservoir; (iii) drinking water distribution system; (iv) drinking water losses in the distribution system; (v) interbasin water transfer; (vi) physical-chemical and biological water quality; (vii) public policies. The main results were: (i) the historical series analyzed showed a population growth rate of 1.8% p.a., while the potable water production was 1.2% p.a., where there was a constant reduction of consumption of 248 L inhabitant-1 day-1 to 203 L inhabitant-1 day-1 in 17 years; (ii) the areas occupied by lakes and reservoirs in BH-JM were increased by 703% in 4 decades, the largest area represented by the public supply reservoir, from which it was estimated that a sediment load of 1,5 thousand tons-1 ; (iii) the geometric growth of the distribution network was of 3.1% p.a., reflecting the linear increase in the number of hydrometric water connections; (iv) the average of drinking water losses in the distribution systems was around 34% over almost two decades, representing losses of about 17.6 million m3 year-1 or R$ 38.3 million year- 1 ; (v) increasingly frequent use of the interbasin water transfer from Atibaia river, a measure that may result in many unfolding and future conflicts over the use of water in the region; (vi) adverse changes in the physical-chemical quality of BH-JM water due to interbasin water transfer, such as the increase in the concentration of metallic ions, turbidity, chloride, among others; (vii) an ample environmental legislative framework related to BH-JM was identified, but with low legal effectiveness in their applications. In view of the results, 49 management guidelines were proposed. Therefore, the methodological approach used demonstrated to be adequate and replicable for other river basins, once that: the Delphi method developed allowed to set up criteria of indicators selection considering the research questions analyzed; the indicators discussion allowed a better understanding of the dynamics involved in each indicator; the indicators structuring in a causal model allowed the information systematization and, thus, it is contributed to the establishment the management guidelines. / Capes-DS
4

Sistem?tica integrativa de Cichlasoma orientale Kullander 1983 e Crenicichla menezesi Ploeg 1991 (Teleostei: Cichlidae) das bacias hidrogr?ficas do Nordeste do Brasil

Berbel Filho, Waldir Miron 30 April 2014 (has links)
Made available in DSpace on 2014-12-17T15:49:15Z (GMT). No. of bitstreams: 1 WaldirMBF_DISSERT.pdf: 3558667 bytes, checksum: 3035c50ccf49225a3c8264f6c395bf14 (MD5) Previous issue date: 2014-04-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / Understanding the historical and ecological relationships which are influent in current biological diversity is one of the most challenging tasks of evolutionary biology. Recent systematics emphasizes the need of integrative approaches to delimit different lineages and species. The northeastern Brazil, mostly placed in Caatinga biome, is characterized by a semi-arid weather, low precipitation and seasonal behavior of rivers. This region is regarded lacking as ichthyological knowledge and one of the most threatened by anthropic activities. Further, will be affected by a massive water diverpsion work that will transfer waters from S?o Francisco basin, to other major four basins: Jaguaribe, Apodi-Mossor?, Piranhas-A?u and Paraiba do Norte. Loss of diversity and richness, hibridizitation, community interactions changes, population homogenization, changes in water quality and flow regime, are examples of environmental impacts already related with similar works. The present study aims to investigate morphological and molecular variation of Cichlasoma orientale Kullander 1983 and Crenicichla menezesi Ploeg 1991, two cichlid species present in northeastern Brazil basins. Further, the study aims to evaluate the influence of geomorphological and climatic processes in this variation, and point some possible impacts of the artificial connectivity which can be brought by S?o Francisco interbasin water transfer to their population dynamics. Geometric morphometrics and phylogeographical analysis were used to investigate the populations from three different hydrological regions. Our results showed a significant morphological variation of populations from basins that are involved in the S?o Franscisco s diversion project, not related to an ancient separation between populations, emphasizing morphological variation which could represent a set of plastic responses to the variable hydrological regime in Northeastern Brazil. The role of plastical responses in naturally variable habitats as well as the potential disturbs that could be brought by the interbasin water transfer works are discussed here. Further, our molecular data allowed us to make inferences about species distribution and their taxonomy, and identification of a potential new species of Crenicichla for S?o Francisco river basin. Our data also allowed to identify some shared haplotypes for both species, which could be related to lineage sorting scenarios or recent gene flow between populations. However a strong structure in most of the pairwise comparisons between populations for both species was revealed. Climatic events such as Atlantic forest regression during the Pleistocene, sea level fluctuations and dispersion by paleorivers in the mouth of Apodi-Mossor? river, and neotectonic events regulating the connection between drainages are likely to have had a contribution for the actual lineages distribution in northeastern Brazil. Further, analysis of molecular variation (AMOVA and SAMOVA) showed that the actual basin s isolation is an important factor to molecular variation, in spite of the signal of recent contact between some basins. Different genetic diversity patterns between species could be related to multiple historic events of colonization, basins landscapes or biological differences. The present study represents the first effort of integrative systematics involving fish species of northeastern Brazil, and showed important morphological and molecular patterns which could be irrecoverably affected by the artificial connection that might be caused by the S?o Francisco interbasin water transfer / O Nordeste brasileiro, majoritariamente imerso no bioma Caatinga, se caracteriza pelo clima semi-?rido, baixa precipita??o e um regime de rios intermitentes. Quanto ao conhecimento ictiofaun?stico, a regi?o ? considerada uma das maiores lacunas mundiais, e uma das mais amea?adas pelas atividades antr?picas. Al?m disso, a regi?o est? passando por obras de transposi??o, que ligar? ?guas do rio S?o Francisco com quatro bacias da regi?o: Jaguaribe, Apodi-Mossor?, Piranhas-A?u e Para?ba do Norte. Perda de diversidade, hibridiza??o de esp?cies, altera??es de comunidade, homogeneiza??o de popula??es, altera??o de qualidade e regime de fluxo de ?gua, s?o impactos ambientais j? atribu?dos a empreendimentos similares. O presente estudo objetiva investigar a varia??o morfol?gica e molecular de Cichlasoma orientale Kullander 1983 e Crenicichla menezesi Ploeg 1991, duas esp?cies com ampla distribui??o ao longo das bacias do Nordeste brasileiro, atrav?s de m?todos de sistem?tica integrativa. Al?m disso, o estudo visa analisar a influ?ncia de fatores clim?ticos e geomorfol?gicos nesta varia??o, e apontar poss?veis impactos da conex?o artificial das bacias envolvidas na transposi??o do rio S?o Francisco. Para estes fins, foram utilizadas an?lises de morfometria geom?trica e filogeogr?ficas com indiv?duos de tr?s ecorregi?es hidrogr?ficas do Nordeste brasileiro. Nossos resultados mostraram que h? uma significativa varia??o morfol?gica nas bacias envolvidas na transposi??o do rio S?o Francisco, que n?o est? ligada ? uma separa??o ancestral das bacias, evidenciando uma varia??o morfol?gica que pode representar um conjunto de respostas pl?sticas ?s constantes transforma??es principalmente relacionadas ao regime h?drico da regi?o. O papel de respostas pl?sticas em ambientes naturalmente vari?veis, assim como o potencial impacto do dist?rbio no regime h?drico a ser trazido pela transposi??o do rio S?o Francisco, s?o discutidos. Al?m disso, nossos dados moleculares permitiram fornecer mais informa??es sobre a distribui??o das esp?cies e sua taxonomia, incluindo a identifica??o de uma potencial nova esp?cie de Crenicichla na bacia do rio S?o Francisco. Os dados tamb?m mostraram alguns hapl?tipos compartilhados para ambas as esp?cies, que podem representar cen?rios incompletos de separa??o de linhagens ou fluxo g?nico recente entre popula??es, por?m forte estrutura??o entre a maior parte das bacias. Eventos clim?ticos como a regress?o da Mata Atl?ntica durante o Pleistoceno, flutua??es do n?vel do mar e a dispers?o por paleorios na por??o estuarina das bacias que desaguam no litoral norte da regi?o nordeste, al?m de eventos neotect?nicos envolvendo captura de cabeceiras, parecem ter contribu?do para a atual distribui??o de linhagens destas esp?cies no Nordeste brasileiro. Al?m disso, an?lises de vari?ncia molecular (AMOVA e SAMOVA) evidenciaram que a atual conjuntura das bacias se mostrou um fator importante para a varia??o molecular, apesar da indica??o de compartilhamento recente entre algumas bacias. Diferen?as de padr?es de diversidade intrapopulacional entre as esp?cies podem estar relacionadas a m?ltiplos eventos hist?ricos de coloniza??o, ou ? diferen?as biol?gicas. O presente estudo representa o primeiro esfor?o de sistem?tica integrativa com esp?cies da ictiofauna continental do Nordeste brasileiro, e revelou varia??es morfol?gicas e moleculares entre drenagens isoladas que podem ser irrecuperavelmente afetadas com a conex?o artificial destas bacias a partir das obras de transposi??o do rio S?o Francisco

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