The goal of this study is to establish an accurate, simple and fast method for analysis of organotin in bio-tissues and for routine analysis of organotin in pollution control. This study also conducted the field survey investigating the accumulation status of butyltin (BT) in organisms and environments for validation of analytical method and applicability in different environmental samples. Stations had been set up from the Sih-Cao fishing port to the upstream of Luermen Stream Estuary. General water quality factors were measured in situ, and water samples, suspended particles, Pacific oysters (Crassostrea gigas), green mussels (Perna viridis), and rockshells (Thais clavigera and Thais rufotincta) were collected in summer (July 2003) and winter (February 2004) seasons and the concentrations of butyltins were measured. Surface sediment samples were also collected from each sampling station and the concentrations of butyltins were measured to present pollution status of butyltins in Luermen Stream Estuary. To determine butyl- and phenyl-tins in fish muscle, a method including base digestion pretreatment, followed by an ethylation-extraction procedure together with gas chromatography-flame photometric detection (GC-FPD) analysis is outlined. Parameters that affect analyte recovery were investigated and optimized. A solution of 3 % (w/v) potassium hydroxide and 1 h digestion time at 60 ¢J were chosen in the base digestion step to ensure complete solubilization of fish muscle and the decomposition of organotins was found to be negligivle. We found that the ratio of fish muscle/reaction solution volume should not exceed 0.2 g (dry weight) per 100 mL in order to avoid the matrix effect caused by the binding of hydrolyzed fish tissue with organotin ions. Ethylation of organotins were conducted at pH 6~7 with a 1 % (w/v) sodium tetraethylborate (NaBEt4) solution for 1 h. This simple and timesaving procedure could be applied to the routine analysis of organotins in other bio-tissues. The BT content of environments and organisms reflected that the tributyltin (TBT) pollution levels were higher in Sih-Cao fishing port than in Luermen Stream. The BT content of organisms reflected more detail TBT pollution status between Sih-Cao fishing port and Luermen Stream. However, the MBT pollution status in Luermen Stream was not reflected in MBT accumulation status of organisms. The ability of TBT accumulation in oysters and mussels was higher than in rockshells. Moreover, oysters had higher TBT accumulation ability than mussels at lower TBT pollution level, but following the increase of TBT pollution level, the ability of TBT accumulation in oysters had shifted to be lower than in mussels. The results also showed that in the higher TBT pollution level, the ratios of MBT and DBT over the total butyltins had changed to higher status and the bioaccumulation factors (BAF) had changed to smaller values in oysters and rockshells. In mussels, this phenomenon was not significant. However, the organisms (oyster, mussel and rockshells) revealed smaller BAF of TBT in Luermen Stream than in the Sih-Cao fishing port entrance. For oysters and mussels, the TBT contents and the composition ratios of TBT in total butyltins were both higher in winter season. All organisms (oysters, mussels and rockshells) had higher ability to accumulate TBT according to the larger BAF observed in summer season. The ability of TBT accumulation in rockshells was lower than in oysters or mussels. Moreover, the BT accumulation status was mainly composed of MBT and DBT (the metabolites of TBT ) in rockshells and TBT in oysters and mussels. That was attributed to higher metabolic rate of TBT in rockshells.

Wird der ökologische oder chemische Zustand der Gewässer nach EG-Wasserrahmenrichtlinie bewertet, können für die Metalle geogene Hintergrundwerte berücksichtigt werden. Sächsische Gewässer weisen regional unterschiedliche Schwermetall- und Arsengehalte auf. Ausschlaggebend dafür sind die natürlichen geogenen Gehalte. Die Anwendung deutschlandweiter Vorgaben ist daher nicht möglich. Für das Erzgebirge und das Vogtland wurden in den Teileinzugsgebieten der Freiberger und Zwickauer Mulde, der Bobritzsch und des Johanngeorgenstädter Schwarzwassers die natürlichen Hintergrundwerte erhoben. Das Untersuchungsgebiet umfasst ein Drittel der Landesfläche Sachsens. Für eine breite Palette von Metallen wurden sowohl im Schwebstoff als auch für die gesamte und gelöste wässrige Phase nach einer neuen Methodik Hintergrundkonzentrationen abgeleitet.

Wird der ökologische oder chemische Zustand der Gewässer nach EG-Wasserrahmenrichtlinie bewertet, können für die Metalle geogene Hintergrundwerte berücksichtigt werden. Sächsische Gewässer weisen regional unterschiedliche Schwermetall- und Arsengehalte auf. Ausschlaggebend dafür sind die natürlichen geogenen Gehalte. Die Anwendung deutschlandweiter Vorgaben ist daher nicht möglich. Für das Erzgebirge und das Vogtland wurden in den Teileinzugsgebieten der Freiberger und Zwickauer Mulde, der Bobritzsch und des Johanngeorgenstädter Schwarzwassers die natürlichen Hintergrundwerte erhoben. Das Untersuchungsgebiet umfasst ein Drittel der Landesfläche Sachsens. Für eine breite Palette von Metallen wurden sowohl im Schwebstoff als auch für die gesamte und gelöste wässrige Phase nach einer neuen Methodik Hintergrundkonzentrationen abgeleitet.

It is an important task that design engineers in practice predict the local scour around bridge piers as accurately as possible because excessive local scour around bridge piers unbalance and demolish the bridges. Many equations have been proposed previously by various researchers, based on their experimental findings, but no general method has been developed so far due to the complexity of the topic. In the present study two new bridge pier groups were employed to investigate the inclination effect of the most upstream and downstream piers on the local scours around all piers. Total of 72 experiments have been conducted with 3 inclination angles, one of which representing the vertical case, each experiment lasting 6 hours, under uniform flow and clear-water conditions for a range of water depths and flow velocities on the uniform bed material. It is clearly observed and measured that the amount of local scour reduces substantially by the effect of inclination in the group piers, especially the reduction in the scour around the most upstream pier is found notable. Based on the experimental data, regression analyses are made and an empirical scour depth equation is developed for each individual pier in the pier groups studied. Comparisons with the similar studies performed by other researchers have been made and the results discussed.

For a bridge engineer, it is very important to estimate the maximum scour depth around the piers as accurately as possible, in order to design the footing safely. Many experimental studies have been performed by several investigators until now, in order to obtain information about scouring mechanism. The aim of this experimental study is to examine the effect of inclination of the dual bridge piers on scour depth. The experiments have been conducted with dual pier models under clear-water conditions, for various uniform flow depths. Scour depths had been measured at four different points around the piers / namely upstream and downstream faces of both piers. Dimensional and non-dimensional scour curves have been developed and presented to show the temporal variation of scour depth. The depths of local scour around inclined piers have been observed to be smaller than the scour depths around vertical piers.

Im 6. Informationsblatt zur »Umsetzung der Wasserrahmenrichtlinie in Sachsen« liegt der Schwerpunkt auf der Umsetzung von Maßnahmen zur Verbesserung des Gewässerzustands. Zum einen wird eine Zwischenbilanz zum Stand der Arbeiten gezogen. Zum anderen wird beleuchtet, ob die bisherigen Anstrengungen ausreichend sind, um die hoch gesteckten Ziele in Sachsen erreichen zu können. Außerdem werden Projekte des LfULG und seiner Partner vorgestellt, die beispielhaft für Sachsen sein können.

Submitted by Edileide Reis (leyde-landy@hotmail.com) on 2013-04-09T19:17:23Z No. of bitstreams: 1 Milai.pdf: 9537585 bytes, checksum: ae908f3b047560efb0b0cf4466295e8c (MD5) / Approved for entry into archive by Rodrigo Meirelles(rodrigomei@ufba.br) on 2013-05-09T18:16:03Z (GMT) No. of bitstreams: 1 Milai.pdf: 9537585 bytes, checksum: ae908f3b047560efb0b0cf4466295e8c (MD5) / Made available in DSpace on 2013-05-09T18:16:03Z (GMT). No. of bitstreams: 1 Milai.pdf: 9537585 bytes, checksum: ae908f3b047560efb0b0cf4466295e8c (MD5) Previous issue date: 2009 / Esta dissertação enfoca a influência do processo de urbanização em bacia urbana. O estudo abrange a Bacia do Rio do Cobre, situada no Subúrbio Ferroviário da Cidade do Salvador, Estado da Bahia. Foram definidos dois objetivos: estudar a influência do processo de urbanização na geração de fatores que impactam a qualidade hídrica da Bacia do Rio do Cobre; e, identificar diretrizes de preservação e conservação direcionadas para recursos hídricos nos Planos Diretores de Desenvolvimento Urbano de Salvador. A metodologia aplicada foi fundamentada na abordagem qualitativa; os dados da pesquisa foram obtidos por pesquisas bibliográfica, documental e pesquisa de campo. Por meio da investigação o estudo culminou com os seguintes resultados: o processo de urbanização na área da Bacia do Rio do Cobre influenciou na geração de fatores que impactam negativamente a sua qualidade hídrica em virtude das características da urbanização que se desenvolveu: espontânea, aleatória, irregular, com densidade incompatível com a capacidade de suporte do meio hídrico, próxima às áreas de cachoeiras e nascentes, com retirada da cobertura vegetal, sem infraestrutura de saneamento básico. O processo de urbanização com as características referidas influenciou na geração de fatores que impactam a qualidade hídrica da Bacia, tais como: assentamento humano, criação de animais, área agrícola, lavagem de roupa, bairros do entorno e complexo industrial, entre outros. As principais consequências negativas para o ecossistema aquático, identificadas no estudo, foram: assoreamento; destruição dos ecossistemas do leito da Bacia e das margens; escoamento direto de resíduos sólidos e lançamento de óleos, esgoto doméstico, embalagens de produtos químicos agrícolas; alteração da qualidade da água; desaparecimento da fauna aquática; desequilíbrio das relações ecológicas do meio; diminuição da biodiversidade e contaminação do lençol freático. O comprometimento da qualidade da água, consequentemente, comprometeu a qualidade de vida da comunidade da bacia em estudo. O estudo ainda concluiu que os Planos Diretores de Desenvolvimento Urbano de Salvador apresentam diretrizes que visam a conservação e preservação dos recursos hídricos. Recomenda-se a reversão do quadro de degradação hídrica da Bacia do Rio do Cobre, por meio da determinação popular e governamental, em virtude do valor ecológico, cultural e religioso da área para a cidade de Salvador. / Salvador

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