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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

Bases para aplicação de índices biológicos no biomonitoramento de ambientes lóticos - comunidade bentônica / Bases for Biological Index use in lotic Environment Biomonitoring - Benthic Community

Watanabe, Helena Mitiko 18 September 2007 (has links)
A utilização da comunidade bentônica em biomonitoramento, como indicadora da qualidade de ambientes aquáticos, encontra-se atualmente bem estabelecida. Das duas abordagens sugeridas pelo Protocolo de Avaliação Rápida da USEPA, a que utiliza um único meso-hábitat mostra-se ideal para o biomonitoramento sendo, portanto, necessário estabelecer qual meso-hábitat utilizar. Este trabalho pretende avaliar a sensibilidade e adequabilidade de diferentes meso-hábitat ribeirinhos em biomonitoramento. Foram estabelecidos oito pontos de amostragem, localizados nos rios Atibainha, Cachoeira e Atibaia, na Bacia Hidrográfica do Rio Piracicaba, São Paulo. Amostras foram coletadas na estação chuvosa (março), para análise de variáveis ambientais (água e sedimento) e biótica (macroinvertebrados bentônicos). Os organismos da comunidade bentônica foram identificados ao nível de família para os principais taxa. Os dados ambientais e bióticos foram submetidos à análise de agrupamento e ordenação, e para o diagnóstico da qualidade do ambiente aquático, índices individualizados e abordagem multimétrica foram utilizados. Tanto as variáveis ambientais quanto a biótica separaram nitidamente regiões de alto (3ª e 4ª ordens) e baixo gradiente (5ª e 6ª ordens). Dos meso-hábitats analisados por meio da comunidade bentônica, apenas canal e margem deposicional mostraram-se promissores e destes, margem deposicional mostrou-se o mais adequado para biomonitoramento, tanto por discernir o gradiente de poluição existente quanto por possibilitar a avaliação integrada de variáveis bióticas, químicas e toxicológicas, o que minimizaria esforços com acréscimo de informações. / The use of benthic communities in biomonitoring, as indicator of aquatic environmental quality is currently well established. Considering the two approaches suggested by Rapid Assessment Protocol of US-EPA, the single mesohabitat approach is ideal for the practical purposes of biomonitoring, being hence necessary to establish which meso-habitat to use. This paper aims to evaluate the sensitivity and suitability of different river meso-habitats for biomonitoring. Eight sampling sites were established along Atibainha, Cachoeira and Atibaia Rivers, in Piracicaba River basin, São Paulo State, Brazil. Sampling were carried out in rainy season (March) to evaluate environmental (water and sediment) and biotic (benthic macroinvertebrates) parameters. The major benthic taxa were identified to family level.. Environmental and biotic data were submitted to cluster and ordination analysis, and for the quality of aquatic environment diagnosis, individualized index and multimetrics approach were used. Both environmental and biotic parameters distinctly discriminated upper (3rd and 4th orders) from lower (5th and 6th orders) gradient regions. Among the meso-habitats analyzed by mean of the benthic community, only channel and depositional bank were promising and of the two, deposicional bank proved to be the most adequate for biomonitoring, both for discerning pollution gradient and for enabling an integrated assessment of biotic, chemical and toxicological parameters, minimizing efforts and adding information
2

Fish as ecological indicators in Mediterranean freshwater ecosystems

Benejam Vidal, Lluís 22 December 2008 (has links)
Podeu escriure el text directament o arrossegar-lo des d'un altre documentL'objectiu d'aquesta tesi és contribuir a l'ús dels peixos continentals com a indicadors de l'estat ecològic a la conca Mediterrània. En el primer treball es va detectar que encara que tots els índex biològics estaven correlacionats significativament, els peixos integren i expressen els estressos de manera i a una escala diferents, aportant una informació complementària als altres índexs. Al segon article es van estudiar els cabals de sis conques catalanes. S'ha mostrat que els règims hídrics estan alterats amb una tendència a la disminució del cabal i del nivell dels aqüífers. S'ha detectat quatre mètriques de peixos que es troben significativament afectades en zones més castigades per manca d'aigua degut a l'activitat humana. Es discuteix la necessitat de conèixer en profunditat el règim hídric de cada conca abans d'utilitzar els índex biològics. Al tercer article es va detectar que la composició d'espècies capturades va variar significativament al llarg del buidat amb un augment de l'alburn (A. alburnus) a les aigües pelàgiques durant els dies de pitjor qualitat de l'aigua, confirmant que l'alburn és més tolerant a la mala qualitat de l'aigua que la madrilleta vera (R. rutilus) i suggereix el seu potencial com a bioindicador. La condició d'aquestes dues espècies va canviar significativament al llarg del buidat de manera molt estreta amb la qualitat de l'aigua. Al quart capítol es va estudiar la biologia dels peixos d'un embassament altament contaminat (Flix). El percentatge de DELT anomalies i la presència de paràsits externs era major en la zona impactada que als punts de control i els valors més alts de pes eviscerat i pes del fetge estaven als punts de control. Les respostes van ser diferents per cada espècie i la carpa va ser la que va mostrar més clarament els impactes. / Podeu escriure el text directament o arrossegar-lo des d'un altre documentThe aim of this thesis is to contribute to the use of freshwater fish as ecological indicators in the Mediterranean basin. In the first article we found that although most biological indices were correlated, fish reflected different ecological aspects due to their particular features. In the second article the stream flow regimes of six Mediterranean basins were studied. A decrease of streamflow and aquifer levels was detected, despite no observed decrease of rainfall precipitation. Of the thirty metrics tested to detect sites impacted by water abstraction, we detected four significant fish metrics. Furthermore, the role of biotic indices when the river is artificially dry is discussed. In the third article we found that species composition in the pelagic zone varied significantly during the drawdown with higher proportion of bleak (A. alburnus) during the days of worst water quality, confirming that bleak is more tolerant than roach (R. rutilus) to poor water quality. The weight-length relationship of roach and bleak also varied significantly during the drawdown with close relationship between water quality and fish condition. In the fourth article the condition and fecundity of freshwater fishes were assessed in a highly polluted reservoir (Flix reservoir). We have shown significant increases of DELT anomalies and ectoparasite prevalences and decreases in condition and fecundity of several freshwater fish at the impacted area. The responses to the pollutants were species-specific and common carp was the species that showed more markedly the effects.
3

Study of Impacts on Waste Activity in the Bioreactor and on Water Quality in the River and Ocean Environment with Effluents Discharges from Tainan Technology Industrial Park

Yang, Cheng-Chen 26 July 2002 (has links)
This study aimed to investigate the activity change of the sludge in a bioreactor after the addition of industrial wastewater and the influence on water quality of nearby waterway after the entrance of the treated effluent. Furthermore, with respect to the industrial effluent¡¦s direct discharge to the near sea, the investigation of water quality was also undertaken to set up the database of water quality for the related receiving waters and further to provide information useful for the future monitoring and assessing the possible water pollution caused by the Tainan Technology Industrial Park (TTIP). At this present study, the TTIP, which was not at the stage of formal operation, was selected as the research object to investigate the possible adverse effects of the effluent from Hi-tech industries on the environment. In the first part of this study, several techniques for sludge diagnosis were used to evaluate the activity of sludge in various types of wastewaters in order to choose appropriate biological indices to represent the performance of a bioreactor. The results showed that dissolved oxygen was proportional to DHA concentration and number of bacteria. In addition, that both suspended solids (SS) and volatile suspended solids (VSS) had poor correlation with dissolved oxygen led to their failure to be the biological indices. In the second part of this study, the influence on the water quality after the treated wastewater discharged into the nearby receiving waters was investigated. The results of field investigation showed that the effluent did not cause significant negative effects on the receiving waters but positive effects instead due to its lowering the concentrations of water pollutants. Summarily, the effluent emitted from the TTIP had no significant impact on the nearby receiving waters by now. However, in the future, when most of the factories in the park begin to produce products, further studies are required to make sure whether the effluent will cause adverse impact on the nearby water environments.
4

Bases para aplicação de índices biológicos no biomonitoramento de ambientes lóticos - comunidade bentônica / Bases for Biological Index use in lotic Environment Biomonitoring - Benthic Community

Helena Mitiko Watanabe 18 September 2007 (has links)
A utilização da comunidade bentônica em biomonitoramento, como indicadora da qualidade de ambientes aquáticos, encontra-se atualmente bem estabelecida. Das duas abordagens sugeridas pelo Protocolo de Avaliação Rápida da USEPA, a que utiliza um único meso-hábitat mostra-se ideal para o biomonitoramento sendo, portanto, necessário estabelecer qual meso-hábitat utilizar. Este trabalho pretende avaliar a sensibilidade e adequabilidade de diferentes meso-hábitat ribeirinhos em biomonitoramento. Foram estabelecidos oito pontos de amostragem, localizados nos rios Atibainha, Cachoeira e Atibaia, na Bacia Hidrográfica do Rio Piracicaba, São Paulo. Amostras foram coletadas na estação chuvosa (março), para análise de variáveis ambientais (água e sedimento) e biótica (macroinvertebrados bentônicos). Os organismos da comunidade bentônica foram identificados ao nível de família para os principais taxa. Os dados ambientais e bióticos foram submetidos à análise de agrupamento e ordenação, e para o diagnóstico da qualidade do ambiente aquático, índices individualizados e abordagem multimétrica foram utilizados. Tanto as variáveis ambientais quanto a biótica separaram nitidamente regiões de alto (3ª e 4ª ordens) e baixo gradiente (5ª e 6ª ordens). Dos meso-hábitats analisados por meio da comunidade bentônica, apenas canal e margem deposicional mostraram-se promissores e destes, margem deposicional mostrou-se o mais adequado para biomonitoramento, tanto por discernir o gradiente de poluição existente quanto por possibilitar a avaliação integrada de variáveis bióticas, químicas e toxicológicas, o que minimizaria esforços com acréscimo de informações. / The use of benthic communities in biomonitoring, as indicator of aquatic environmental quality is currently well established. Considering the two approaches suggested by Rapid Assessment Protocol of US-EPA, the single mesohabitat approach is ideal for the practical purposes of biomonitoring, being hence necessary to establish which meso-habitat to use. This paper aims to evaluate the sensitivity and suitability of different river meso-habitats for biomonitoring. Eight sampling sites were established along Atibainha, Cachoeira and Atibaia Rivers, in Piracicaba River basin, São Paulo State, Brazil. Sampling were carried out in rainy season (March) to evaluate environmental (water and sediment) and biotic (benthic macroinvertebrates) parameters. The major benthic taxa were identified to family level.. Environmental and biotic data were submitted to cluster and ordination analysis, and for the quality of aquatic environment diagnosis, individualized index and multimetrics approach were used. Both environmental and biotic parameters distinctly discriminated upper (3rd and 4th orders) from lower (5th and 6th orders) gradient regions. Among the meso-habitats analyzed by mean of the benthic community, only channel and depositional bank were promising and of the two, deposicional bank proved to be the most adequate for biomonitoring, both for discerning pollution gradient and for enabling an integrated assessment of biotic, chemical and toxicological parameters, minimizing efforts and adding information

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