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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

Habitats de desova de peixes migradores no trecho a jusante das Cataratas do Iguaçu, Parque Nacional do Iguaçu / Spawning habitat for migratory fish in the downstream of the Iguazu Falls, Iguazu National Park

Tosetto, Everton Giachini 20 August 2013 (has links)
Made available in DSpace on 2017-07-10T14:38:20Z (GMT). No. of bitstreams: 1 Everton Tosetto.pdf: 1346484 bytes, checksum: eea1541efb83dfd6042a4aa78dc65582 (MD5) Previous issue date: 2013-08-20 / Due to fragmentation of the middle Paraná River by the dam and the Itaipu Yacyretá , the conservation of fish species that perform reproductive migration depends on the successful search for alternative routes for reproduction . Thus, this study sought to determine whether the stretch of the Iguazu River between Iguazu Falls and its mouth , located downstream of Itaipu is being used with play area and these species also describe the characteristics of these habitats . The results showed that the reproduction of seven species of migratory fish , vulpinus Raphiodon , Prochilodus lineatus , Salminus brasiliensis , Leporinus elongatus , Pimelodus ornatus maculatus Pimelodus and corruscans Pseudoplatystoma occurs in the studied mainly in habitats located within the Iguazu National Park that have favorable characteristics for spawning and transport of eggs and larvae , as high concentrations of dissolved oxygen , rapids and currents , wide riparian vegetation and substrates that provide good conditions under / Devido a fragmentação do médio Rio Paraná pelas represas de Itaipu e Yacyretá, a conservação das espécies de peixes que realizam migrações reprodutivas depende do sucesso na busca por rotas alternativas para a reprodução. Assim esse trabalho buscou verificar se o trecho do Rio Iguaçu entre as Cataratas do Iguaçu e a sua foz, situada a jusante de Itaipu está sendo usado com área de reprodução dessas espécies e também descrever as características desses habitats. Os resultados evidenciaram que a reprodução de sete espécies de peixes migradores, Raphiodon vulpinus, Prochilodus lineatus, Salminus brasiliensis, Leporinus elongatus, Pimelodus ornatus, Pimelodus maculatus e Pseudoplatystoma corruscans, ocorre no trecho estudado, principalmente nos habitats localizados no interior do Parque Nacional do Iguaçu, que apresentam características propícias para a desova e o transporte de ovos e larvas, como altas concentrações de oxigênio dissolvido, corredeiras e correntezas, ampla vegetação ripária e substratos que proporcionam boas condições de abrigo
2

Computational fluid dynamics applications for the Lake Washington Ship Canal

Nielsen, Adam C. 01 May 2011 (has links)
The Seattle District wants to better manage the Ballard Locks and structures along the Lake Washington Ship Canal (LWSC) in a way that will maintain the environmental sustainability and biodiversity in the area. Due to strict salt water intrusion regulations in the LWSC, the Seattle District is working on upgrading their management practices such that they will resolve two inter-related problems. First, to improve the fish passage conditions for migrating salmon; and second, to learn how to better manage the salt wedge that forms and intrudes upstream. Based on the hydrodynamic and water quality results that are produced by this research, the Engineer Research and Development Center (ERDC) Portland Office will use their Eulerian-Lagrangian-Agent-Model (ELAM) to analyze fish patterns, looking for the most beneficial management schemes that assist salmon in migrating upstream. This research implemented CFD engineering techniques to help better understand the effectiveness of the hydraulic structures in the area, as well as come up with management practices that both mitigate the salt water intrusion from Puget Sound, and improve the migrating passages for salmon.
3

Sistemas para a transposição de peixes. / Fish transponding system: fishways.

Martins, Sidney Lazaro 27 June 2000 (has links)
Sistemas para a Transposição de Peixes são implantados para atenuar os efeitos negativos dos barramentos sobre os peixes migradores ou de piracema. No Brasil, como na maioria dos paises subdesenvolvidos, devido a fatores históricos, financeiros, políticos, institucionais e culturais desfavoráveis, há uma defasagem tecnológica quanto aos Sistemas para a Transposição de Peixes, pelo menos secular, com conseqüências imensuráveis ao ambiente e ao universo dos peixes. A importância dos nossos peixes fluviais, onde se destacam os migradores como os de maior interesse comercial e esportivo, é indiscutível. Assim, esta dissertação propõe-se a inventariar o "estado da arte" dos Sistemas para a Transposição de Peixes, isto é, conhecer as necessidades dos nossos peixes, estudar alternativas hidráulico-estruturais de transposição e, também, vencer as correntes retrógradas. Os estudos e projetos internacionais não devem ser aplicados indiscriminadamente para a realidade nacional, pois diferem quanto à diversidade dos nossos peixes, sob a pena de incorrer nos insucessos como os australianos africanos e os brasileiros. Nesta dissertação, após à introdução, há um breve relato sobre a importância entre as relações ecológicas e ambientais; relações entre os elementos vivos e o meio aquático e as interferências humanas; conhecimentos físicos e biológicos sobre os peixes; história, conceitos fundamentais e legislação sobre os STP's; estudos para viabilização de estruturas-tipo, em modelo reduzido e estudos futuros. / Fish Transponding System are usually adopted to mitigate negative effects of dam and reservoir construction on migratory fishes. In Brazil, as with most undeveloped countries, owing to historical, political, economical and cultural adverse factors, there is a centenary technological gap relating Fish Transponding System, which has caused unbearable consequences to environment and to the fish realm. The importance of our fluvial fishes, among which the migratory ones represent major commercial and sportive interest, is unquestionable. This dissertation intends to furnish information on the State of the Art in Fish Transponding System, to present native fish habits and needs, to compare hydraulic and structural transponding system types and, last but not least, to introduct a new way of facing and dealing with fish transponding problems, in a contribution to breaking the prevailing retrograde vision. This dissertation shows that international current projects and practices should not be adopted widespread to national reality, as they usually don’t match our fishes habits and needs; the adoption of those practices could lead to a project breakdown, according to some recorded Australian, African, and even Brazilian experiences. The work also presents a brief explanation on: ecological and environmental relations; living specimens, aquatic media and human actions; Fish physical and biological knowledge; history, basic concepts and legislation about FTS; considerations aiming to make feasible standard structures, reduced scale models and further investigations.
4

Sistemas para a transposição de peixes. / Fish transponding system: fishways.

Sidney Lazaro Martins 27 June 2000 (has links)
Sistemas para a Transposição de Peixes são implantados para atenuar os efeitos negativos dos barramentos sobre os peixes migradores ou de piracema. No Brasil, como na maioria dos paises subdesenvolvidos, devido a fatores históricos, financeiros, políticos, institucionais e culturais desfavoráveis, há uma defasagem tecnológica quanto aos Sistemas para a Transposição de Peixes, pelo menos secular, com conseqüências imensuráveis ao ambiente e ao universo dos peixes. A importância dos nossos peixes fluviais, onde se destacam os migradores como os de maior interesse comercial e esportivo, é indiscutível. Assim, esta dissertação propõe-se a inventariar o "estado da arte" dos Sistemas para a Transposição de Peixes, isto é, conhecer as necessidades dos nossos peixes, estudar alternativas hidráulico-estruturais de transposição e, também, vencer as correntes retrógradas. Os estudos e projetos internacionais não devem ser aplicados indiscriminadamente para a realidade nacional, pois diferem quanto à diversidade dos nossos peixes, sob a pena de incorrer nos insucessos como os australianos africanos e os brasileiros. Nesta dissertação, após à introdução, há um breve relato sobre a importância entre as relações ecológicas e ambientais; relações entre os elementos vivos e o meio aquático e as interferências humanas; conhecimentos físicos e biológicos sobre os peixes; história, conceitos fundamentais e legislação sobre os STP's; estudos para viabilização de estruturas-tipo, em modelo reduzido e estudos futuros. / Fish Transponding System are usually adopted to mitigate negative effects of dam and reservoir construction on migratory fishes. In Brazil, as with most undeveloped countries, owing to historical, political, economical and cultural adverse factors, there is a centenary technological gap relating Fish Transponding System, which has caused unbearable consequences to environment and to the fish realm. The importance of our fluvial fishes, among which the migratory ones represent major commercial and sportive interest, is unquestionable. This dissertation intends to furnish information on the State of the Art in Fish Transponding System, to present native fish habits and needs, to compare hydraulic and structural transponding system types and, last but not least, to introduct a new way of facing and dealing with fish transponding problems, in a contribution to breaking the prevailing retrograde vision. This dissertation shows that international current projects and practices should not be adopted widespread to national reality, as they usually don’t match our fishes habits and needs; the adoption of those practices could lead to a project breakdown, according to some recorded Australian, African, and even Brazilian experiences. The work also presents a brief explanation on: ecological and environmental relations; living specimens, aquatic media and human actions; Fish physical and biological knowledge; history, basic concepts and legislation about FTS; considerations aiming to make feasible standard structures, reduced scale models and further investigations.
5

Kalojen kuninkaan tie sukupuuttoon:Kemijoen voimalaitosrakentaminen ja vaelluskalakysymys 1943–1964

Alaniska, K. (Kari) 20 November 2013 (has links)
Abstract The harnessing of Kemijoki-river became topical at the end of 1944 after the second world war when Pohjolan Voima Ltd, founded by industrial representatives, combined the re-building of the destroyed bridges and building of Isohaara power plant. The government eagerly supported the project. Kemijoki-river was the most important salmon river in Europe, and therefore the fishing issue concerned many. The power company and the politicians promised to handle the fishing issue after it had been thoroughly examined. At first fish transfers were attempted, for which the company expropriated the water areas below the dam. The fish transfers were managed by Lapin läänin Kalastuskuntain liitto. The transfers faced a lot of critique from the beginning, but no intervention took place. Most of the salmon were sold to cover the expenses. As the discontent increased, a fish lift was built in summer 1951. As expected, it could not meet the expectations. However, it could be considered to be the fish transfer device required by law. The next step was to focus on the fish farming, which was widely advertised. But unfortunately also those results were meager. A state-run Kemijoki Ltd, founded in 1954, built also the other power plants of the river Kemijoki. The outlook of Kemijoki Ltd to the fishing issue was similar to Pohjolan Voima Ltd; it was simply inessential for the nation. Fish ladders were not considered necessary, and officially not even credited. The politicians and other authorities also agreed with this view. The local fishing spokesmen still insisted on demanding fish roads, or at least proper compensations for the losses of salmon fishermen, but the issue seemed to be delayed indefinitely due to various problems. In 1964 the Isohaara power plant received the final planning permission. Simultaneously, it also defined the compensations, which raised discontent and started a thread of complaints. The main reason for the disappearance of salmon in Kemijoki-river can be concluded to be due to the unofficial alliance of the industry and the politicians; the water power of Kemijoki-river needed to be harnessed quickly to serve the development of the society. It was advertised especially for the advanced well-being of Lapland. Furthermore, this action was supported specifically from the point of view of the local employment. Pohjolan Sanomat, the organ of Maalaisliitto, strongly supported the power plant building of northern waters argumenting the regional policy. This dampened most of the criticism. It can be stated that all the other functions of Kemijoki-river were underestimated. The function of the river was only to produce electricity, which quickly led to the extinction of migratory fish by the 1960s. The salmon in Kemijoki-river had become history. / Tiivistelmä Kemijoen valjastaminen tuli ajankohtaiseksi loppuvuodesta 1944, kun teollisuuden edustajien toimesta perustettu Pohjolan Voima Oy yhdisti tuhoutuneiden siltojen ja Isohaaran voimalaitoksen samanaikaisen rakentamisen. Valtiovalta kannatti hanketta nopeasti. Kemijoki oli Euroopan tärkein lohijoki, joten kalakysymys huolestutti. Voimayhtiö ja poliitikot lupasivat hoitaa asian, kun sitä olisi ensin tutkittu. Aluksi kokeiltiin ylisiirtoja, joiden järjestelyjä varten yhtiö pakkolunasti padon alapuolisen vesialueen. Ylisiirrot sai hoitaakseen Lapin läänin Kalastuskuntain liitto. Toimintaa arvosteltiin alusta pitäen, mutta siihen ei puututtu. Suurin osa lohista myytiinkin kulujen kattamiseksi. Tyytymättömyyden lisääntyessä rakennettiin kalahissi, joka valmistui kesällä 1951. Kuten oli arveltu, se ei kyennyt täyttämään odotuksia, mutta sen voitiin katsoa olevan lain edellyttämä kalansiirtolaite. Seuraavaksi päätettiin tehostaa kalanviljelytoimintaa, jota mainostettiin laajasti. Myös sen tulokset jäivät kehnoksi. Vuonna 1954 perustettu valtiojohtoinen Kemijoki Oy rakensi joen muut vesivoimalaitokset. Kemijoki Oy suhtautui kalakysymykseen kuten Pohjolan Voima; asia oli toisarvoinen. Kalaportaita ei pidetty tarpeellisina, eikä niihin virallisesti edes uskottu. Myös poliitikot ja muut päättäjät asettuivat samalle kannalle. Paikalliset kalastuksen edustajat vaativat yhtä kalateitä tai ainakin kunnollisia korvauksia, mutta asia tuntui erilaisten ongelmien takia aina vain viivästyvän. Vuonna 1964 Isohaaran voimalaitos sai lopullisen rakennuslupansa. Siinä määriteltiin myös korvaukset, jotka herättivät laajaa tyytymättömyyttä ja saivat aikaan valituskierteen. Tärkein syy lohen katoamiseen löytyy teollisuuden ja poliitikkojen epävirallisesta liitosta: Kemijoen vesivoima haluttiin nopeasti valjastaa palvelemaan yhteiskunnan kehittämistä. Hanketta markkinoitiin erityisesti Lapin hyvinvoinnin edistämisellä. Toimintaa kannatettiin nimenomaan työllisyysnäkökulmasta. Myös Maalaisliiton äänenkannattaja Pohjolan Sanomat tuki voimakkaasti pohjoisen vesirakentamista aluepoliittisin perustein. Tämä oli omiaan vaimentamaan kritiikkiä. Voidaan todeta, että Kemijoen kaikkia muita käyttöarvoja aliarvioitiin. Joen tehtäväksi jäi vain ja ainoastaan sähköntuottaminen, joka johti vaelluskalakantojen nopeaan sukupuuttoon 1960-luvulle tultaessa. Kemijoen lohesta oli tullut historiaa.
6

Estrutura da população e período reprodutivo de Leporinus piau Fowler, 1941(Characiformes: Anostomidae) no reservatório de pau dos ferros, semiárido brasileiro / Population structure and reproductive dynamic of leporinus piau Fowler (Characiformes: Anostomidae) in the Pau dos Ferros reservoir, Brazilian semiarid

Araújo, Darlan Dantas Alves de 27 February 2015 (has links)
Made available in DSpace on 2016-08-15T20:31:31Z (GMT). No. of bitstreams: 1 DarlanDAA_DISSERT.pdf: 1327863 bytes, checksum: 20f80b67329558ad38d3402c80b1f9c9 (MD5) Previous issue date: 2015-02-27 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / In the brazilian northeast due to seasonality of rivers and modest hydrological network, water security policy was established, based on the accumulation of water during the rainy season, through the reservoirs construction. This process generate human benefits, but also ecological consequences such as loss of aquatic biodiversity, change in the connectivity of water bodies and modification of biological processes such as reproduction and recruitment of species. In Apodi/Mossoró River basin , Leporinus piau Fowler,1941 is quite important for artisanal and subsistence fishing, however it is necessary to better understand their biology, to establish more effective conservation and management measures. In this context, the objective this work was to study the population structure and reproductive dynamics of Leporinus piau (Fowler, 1941), in the reservoir of Pau dos Ferros, Brazilian semiarid. Specimens were collected quarterly from February 2011 to November 2012 using gillnets. The specimens captured were counted and measured the standard length (cm), total weight (g), and dissected to identify sex, and gonadal maturity stage and weight of gonads (g). Were captured 555 individuals. The highest CPUE value was registered in May/2011 (0.0259 ind. m2*h) and lowest was in August/2012 (0.0008 ind. m2*h). The standard length ranged between 5.9 and 20.7cm and total weigh between 4.16 and 271.50g. The length class of 10-15cm was the most frequent of individuals captured for both sexes. The species presented isometric growth (b=3.01) and L50 was estimated to be 12.76cm. Of individuals captured, 276 were juveniles, 180 males and 99 females. The highest GSI value was observed in February/2011 for females (10.69) and males (5.72). There was a significant a positive correlation between GSI and rainfall. We conclude that the population of L. piau is established in the reservoir with some alterations its population attributes and reproductive period was determined between February and May / No nordeste brasileiro devido a sazonalidade dos rios e rede hidrológica modesta, foi estabelecida uma política de segurança hídrica, baseada na acumulação de água nos períodos de chuva, pela construção de reservatórios. Este processo gerou benefícios humanos, mas também consequências ecológicas, como a perda de biodiversidade aquática, alteração na conectividade dos corpos d água e modificação de processos biológicos como a reprodução e o recrutamento de espécies. No reservatório de Pau dos Ferros, bacia do Rio Apodi/Mossoró, a espécie Leporinus piau Fowler,1941, apresenta grande importância na pesca artesanal e de subsistência, no entanto é necessário conhecer melhor a sua biologia, para estabelecer medidas de conservação e manejo pesqueiro mais eficazes.Neste contexto, o objetivo do trabalho foi avaliar a estrutura da população e a dinâmica reprodutiva de L.piau no reservatório de Pau dos Ferros. As capturas foram feitas com redes de espera de diferentes malhas, entre 17h e 05h. Os peixes capturados foram contados, medidos o comprimento padrão (cm) e peso total (g) e dissecados para identificação do sexo e estágio de maturação gonadal. O maior valor de CPUE ocorreu em maio de 2011 (0,0259 ind. m2 * h) e o menor em agosto de 2012 (0,0008 ind. m2 * h). O comprimento padrão variou de 5,9 a 20,7cm e o peso de 4,16 a 271,5g. A classe de tamanho 10 a 15cm foi a mais frequente para os dois sexos. A espécie apresentou crescimento isométrico (b=3,01) e, L50 estimado em 12,76cm. Foram coletados 555 indivíduos, 276 jovens e 279 adultos, destes 180 machos e 99 fêmeas (1,81: 1)M:F. O maior valor de IGS ocorreu em fevereiro de 2011 para fêmeas (10,69) e machos (5,72). Houve correlação significativa e positiva entre IGS e pluviosidade. Concluímos que a população de L. piau está estabelecida no reservatório com alterações em seus atributos populacionais como a proporção sexual ou mesmo o comprimento de primeira maturação e o período reprodutivo ocorreu entre fevereiro e maio
7

Análises morfométricas para predições do desempenho natatório de duas espécies de peixes neotropicais migradoras de longas distâncias / Morphometric analysis for swimming performance prediction of two long distances migratory neotropical species

Assumpção, Lucileine de 29 July 2010 (has links)
Made available in DSpace on 2017-07-10T18:13:24Z (GMT). No. of bitstreams: 1 Lucileine de Assumpcao.pdf: 365155 bytes, checksum: e34cb08ebfe3d7fe233342e001a86050 (MD5) Previous issue date: 2010-07-29 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / This study aimed to evaluate the morphometric characteristics related to swimming performance of two migratory neotropical species, of long distances, which would subsidize the study of swimming performance and the planning of futures fish pass systems. A total of 80 adult fish of the species Leporinus elongatus and Prochilodus lineatus (40 of each one) were analyzed, collected on the fish pass of Sergio Motta Hydroelectric Power Plant (Porto Primavera), high Paraná river, during November 2007 to January 2008 and October 2009. Thirteen morphological measurements were done to obtain eight morphometric ratios (muscle ratio, propulsive ratio, fineness ratio, aspect ratio, caudal peduncle depth factor, caudal fin length ratio, pectoral fin ratio and length from nose to pectoral fin base ratio) considered potentially important to describe the fish swimming performance. The Principal Component Analysis (PCA) and the Analysis of variance were applied to verify the morphological diversification pattern between the two species. Leporinus elongatus and Prochilodus lineatus differed regarding morphometric characteristics related to swimming performance, as muscle ratio, caudal fin length ratio, caudal peduncle depth factor, length from nose to pectoral fin base ratio and fineness ratio. These morphometric ratios can be used to predict the swimming performance of the studied species. However, it is important to emphasize the need of more studies related to survey of swimming performance (tests of prolonged and burst speed) to predict if the species presented differences for swimming speed/performance, whereas the predictive character of this kind of approach would give better precision to analysis, besides contributing significantly to subsidize the absence of basic information about the biology of our neotropical migratory native species. / Este estudo teve como objetivo avaliar as características morfométricas relacionadas ao desempenho natatório de duas espécies de peixes neotropicais migradoras, de longas distâncias, as quais poderão subsidiar os estudos de capacidade natatória e o planejamento de futuros sistemas de transposição para peixes. Um total de 80 peixes adultos das espécies Leporinus elongatus e Prochilodus lineatus (40 de cada espécie) foram analisados, coletados na escada para peixes da Usina Hidrelétrica Engenheiro Sergio Motta (Porto Primavera), alto rio Paraná, no período de novembro de 2007 a janeiro de 2008 e em outubro de 2009. Treze medidas morfológicas foram realizadas para obtenção de oito razões morfométricas (razão muscular, razão propulsora, razão fineza, razão aspecto, fator altura do pedúnculo caudal, razão comprimento da nadadeira caudal, razão nadadeira peitoral e razão comprimento da ponta do focinho à base da nadadeira peitoral) consideradas potencialmente importantes para descrever o desempenho natatório dos peixes. A Análise dos Componentes Principais (ACP) e a Análise de Variância foi aplicada para verificar o padrão de diversificação morfológica entre as duas espécies. Leporinus elongatus e Prochilodus lineatus diferiram quanto às características morfométricas relacionados ao desempenho natatório, como a razão muscular, razão comprimento da nadadeira caudal, fator altura do pedúnculo caudal, razão distância da ponta do focinho à base da nadadeira peitoral e razão fineza. Essas razões morfométricas podem ser utilizadas para predizer o desempenho natatório das espécies estudadas. Ressalva-se, no entanto, a necessidade da realização de estudos relativos a levantamento da capacidade natatória (testes de velocidade prolongada e de explosão) para predizer se as espécies apresentam diferenças nas velocidades de natação/capacidade natatória, uma vez que o caráter preditivo deste tipo de abordagem forneceria maior precisão às análises, além de contribuir, de modo significativo, para subsidiar a ausência de informações básicas sobre a biologia de nossas espécies migradoras neotropicais.

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