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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.
31

How to Face Uncertainty in Phosphorus Abatement Decisions in Water Management / Jak čelit nejistotě při rozhodování o odstranění fosforu ve vodohospodářství

Brabec, Jan January 2016 (has links)
Implementation of EU Water Framework Directive has led to an increased demand for cost-benefit analysis in water management. The directive introduces a good status, which is required on all water bodies by 2027. Excessive phosphorus inflows are one of the main reasons for not meeting the criteria in the Czech Republic. If achieving of the good status is not cost-proportionate, exemption can be applied. Many different methodologies were created across different states, including Czech official methodology by Slavíková et al. (2015). However, this methodology does not deal with uncertainty of measures effectiveness. This thesis describes how to implement the uncertainty into calculations using Bayesian networks. A case study of Stanovice water reservoir demonstrates the approach practically. Results of the Bayesian network show, that selected measures with available data eliminate desired amount of phosphorus in 70% of all cases. This reduction is most likely sufficient, because it holds for the upper estimate of required abatement (60 to 200 kg). Based on comparison of benefits and costs, it seems net benefits are generated by implementing suggested measures. Therefore, policy recommendation is to implement the selected measures.
32

Umsetzung EG-WRRL in Sachsen - Untersuchung zur wirtschaftlichen Fragestellung der Europäischen Wasserrahmenrichtlinie (EG-WRRL) – Umsetzung von Artikel 9 EG-WRRL in Sachsen

Opitz, Rüdiger, Kunz, Hannelore, Donner, Ute, Oehmichen, Peggy, Dehnert, Jörg 19 October 2009 (has links)
Die Studie ermittelt den betriebswirtschaftlichen Kostendeckungsgrad bei 194 sächsischen Wasserver- und Abwasserentsorgern. Der Kostendeckungsgrad liegt bei den Wasserversorgungsleistungen bei 99 Prozent und bei den Abwasserentsorgungsleistungen bei 95 Prozent für Teil- bzw. bei 98 Prozent für Vollentsorgung. Damit hat der Freistaat Sachsen bei der Umsetzung des Grundsatzes der Kostendeckung nach Artikel 9 der EG-WRRL einen guten Stand erreicht. Nach der Studie können in Sachsen allerdings künftig Probleme bei der Beibehaltung dieser Kostendeckungsgrade auftreten. Ursachen sind die demografische Entwicklung, die Entwicklung der Rohstoffpreise, die prognostizierte Klimaentwicklung und höhere Anforderungen an den Reinheitsgrad. Um den erreichten Stand halten zu können, ist eine regelmäßige Überwachung der Kostendeckungsgrade erforderlich. Die Studie enthält Vorschläge zur Erhaltung bzw. Verbesserung der Kostendeckung.
33

Gefährliche Stoffe in Kläranlagen

Schneider, Petra, Günther, Thomas, Gottschalk, Nicole, Zänder, Daniel 22 April 2010 (has links)
Gefährliche Stoffe gelangen durch Abwässer aus Haushalten, Industrie und Landwirtschaft in Kläranlagen. Während der mechanisch-biologischen Abwasserbehandlung in konventionellen Kläranlagen werden nur wenige Stoffe mit toxischen, persistenten und bioakkumulierenden Eigenschaften eliminiert. Der Bericht beschreibt die Eigenschaften gefährlicher Stoffe - darunter Industriechemikalien, Pflanzenschutzmittel, Arzneistoffe, Hormone und Metalle, ermittelt Quellen des Stoffeintrages und leitet Möglichkeiten zur Verringerung der Stoffeinträge ab. In Laborkläranlagen wurde eine Methodik entwickelt, mit der bei Anlagen mit biologischer Grundreinigung und weitergehender Reinigung (Stickstoffeliminierung) die Eliminierungsrate für ausgewählte gefährliche Stoffe ermittelt werden kann. Die Eliminationsraten der untersuchten gefährlichen Stoffe sind sehr unterschiedlich. Während ausgewählte Pestizide nur in geringem Umfang eliminiert werden (Bentazon < 40 Prozent, Dichlorprop < 30 Prozent, Dibutylzinn < 50 Prozent), werden für Nonylphenolethoxylate, Phthalate und Trichlormethan hohe Eliminationsraten mit bis zu 99 Prozent ermittelt.
34

Erosion 3D Sachsen

Schmidt, Walter, Schindewolf, Marcus 14 June 2010 (has links)
Für die Erstellung von Bewirtschaftungs- und Maßnahmenplänen (FFH, EU-WRRL) ist es erforderlich, den bislang noch sehr hohen Aufwand für die Datenbeschaffung und -generierung im Rahmen der Modellierung mit EROSION 3D zu senken. Erreicht werden soll eine schnellere sowie effizientere Abschätzung von Landnutzungsänderungen, Landschaftseingriffen, des Klimawandels usw. auf Oberflächenabfluss, Bodenabtrag sowie Sedimenteintrag in Gewässer mit EROSION 3D. Im vorliegenden Projekt ist es gelungen, Parametrisierung und Modellanwendung so zu kombinieren, dass eine Bodenabtragssimulation mit dem Modell EROSION 3D flächendeckend für Sachsen mit vertretbarem Zeitaufwand durchführbar ist. Der korrigierte und angepasste Geo-Basisdatensatz liefert die Primärinformationen zur Datenbankabfrage der Parametrisierungssoftware DPROC. Durch eine interaktive Flächenauswahl, kombiniert mit einem Flächendatenzuschnitt, können Landnutzungs- und Bearbeitungsszenarien für hydrologische Einzugsgebiete oder Oberflächenwasserkörper schnell parametrisiert werden. Die grundlegend korrigierte und erweiterte Datenbank des DPROC erlaubt die verbesserte Abschätzung erosionsrelevanter Bodenparameter, besonders für die dauerhaft konservierende Bodenbearbeitung und die Direktsaat. Die umfangreiche Dokumentation der Arbeitsschritte und die Transparenz der Datenbank ermöglichen es, jederzeit Aktualisierungen (Geo-Basisdaten) und Erweiterungen (DPROC-Datenbank) vorzunehmen. Von den Projektergebnissen profitieren vor allem die Anwender des Programms EROSION 3D. Beim Druck des Dokumentes ist zu beachten, dass die Karten im Format DIN A3 erstellt wurden.
35

Optimierung N-Management

Heinitz, Franziska, Albert, Erhard, Reinicke, Frank, Wagner, Bernhard 10 March 2011 (has links)
In 16 sächsischen Landwirtschaftsbetrieben wurde das Stickstoff-Management umfassend analysiert. Das Projekt hatte zum Ziel, die N-Bilanzüberschüsse zu reduzieren und betriebsbezogene Maßnahmen zur optimalen N-Nutzung abzuleiten. Es geht konform mit der Vorgabe der Wasserrahmenrichtlinie, die Nährstoffeinträge in Gewässer und Grundwasser wirksam zu verringern. Bilanziert wurde mit dem in Sachsen entwickelten Programm BEFU und dem Umwelt- und Betriebsmanagementsystem REPRO. Die untersuchten Betriebe wiesen aufgrund der Standortbedingungen eine hohe Auswaschungsgefahr für N-Überschüsse auf. In den Szenariorechnungen mit REPRO zeigte sich, dass durch den Anbau von Zwischenfrüchten und einem reduzierten N-Einsatz die N-Salden und die potenzielle Nitratauswaschung deutlich reduziert werden können. Der Bericht enthält zahlreiche Vorschläge zur Optimierung des N-Managements im Betrieb und beweist das erhebliche Potenzial zur Minderung der Nitratverluste und Nitratbelastung.
36

Hidroelektrinių plėtros planavimo tyrimai / Hydropower development planning studies

Vansevičiūtė, Justina 16 June 2010 (has links)
Upių ūkinę veiklą, pvz. hidroenergetiką, galima tam tikromis sąlygomis plėtoti saugomas teritorijas (pavyzdžiui, ekologinio tinklo NATURA 2000). Šios direktyvos 6 straipsnis 2001 m. buvo perkeltas į Saugomų teritorijų įstatymą, tačiau praktinis jo nuostatų taikymas išliko apribotas, ypač šio straipsnio 3 ir 4 dalių nuostatos. Tam, kad reikalavimas dėl planų ir projektų vertinimo veiktų sklandžiai Lietuvoje, priimti Planuojamos ūkinės veiklos poveikio aplinkai vertinimo ir Teritorijų planavimo įstatymas. Tam leidžiama atlikti veiklos poveikių aplinkai vertinimą. Visos didelės ir didesnės upės (Nemunas, Neris, Merkys, Minija ir kt.) yra uždraustos ištisai planuoti ir statyti užtvankas. Draudimo teisinis pagrindas – ES aplinkosaugos direktyvos, rekomendacijos (Berno, HELCOM, IBSFC), kurias Lietuva pasirašė. Nemune, Neryje ir kitose upėse yra ruožų, kuriuose nėra nė vieno draustinio (remiantis Saugomų teritorijų įstatymu) ir kurie yra techniškai tinkami užtvankoms ir hidroelektrinėms statyti, tačiau remiantis Lietuvos pasirašytomis ES aplinkosaugos direktyvomis ir rekomendacijomis (Berno, HELCOM, IBSFC), yra uždrausta planuoti ir statyti užtvankas. Siekiant bent dalinai atkurti pažeistą dinaminę pusiausvyrą ir ekologinį upių vientisumą rekomenduojama, HE kur yra galimybė, bei būtinybė įrengti žuvitakius bei gamtosauginio debito praleidimo priemones. Įrengimą derinti su migracinių koridorių atvėrimo eiliškumu bei svarba. ES Bendrosios Vandens Politikos direktyvos (BVPD) (2000/... [toliau žr. visą tekstą] / The proceeding of rivers for example: water-power can be expanded or lifted and it’s possible to do the assessment of influence for environment. All rivers (bigger) are banned for planning and building weirs. The basis of insurance are: EU directive of environment, guidelines which Lithuania signed on. There are sectors in the rivers of Nemunas or Neris where is no reserve at all and they are suitable for building weirs and hydroelectric. Trying to restore the affected dynamic balance and the ecological integrity is recommended to equip fish-ladder. The equipment should be regulated with priority and importance of passages priority too. The implementation of WFD is given to keep and to encourage the use of water power and to improve ecological conditions of water fields. The directive of the EU (2000/60/EC): to build the new hydroelectric is allowed if there are some problems such as: output of electric power, protection from the flood, navigation, water supply. Hydroelectric plants should be adjusted to a natural river run off. Suitable places might be those, which have no objections to recent acts. Inappropriate rivers are those which are in protected territory.
37

Informationsblatt / Freistaat Sachsen, Landesamt für Umwelt, Landwirtschaft und Geologie

11 June 2014 (has links) (PDF)
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.
38

Contaminant hydrogeochemistry and aquatic ecosystem health at abandoned metal mines : the Afon Twymyn, central Wales

Byrne, Patrick January 2009 (has links)
Following the decline of the UK metal mining industry by the 1920s, over 3,000 abandoned metal mines exist in England and Wales. Contaminated drainage from this historical industry causes approximately 20% of all water quality failures in England and Wales. In this thesis, a holistic geographical approach, incorporating aspects of hydrology, hydrogeochemistry and freshwater ecology, is employed to investigate the hydrological, sedimentological and ecological impacts of the abandoned Dylife lead/zinc mine on the Afon Twymyn (central Wales). Examination of river sediment quality highlights the need for measurements of the quality of this component of the river ecosystem and, in particular, measurement of bioavailable as opposed to total metals. The majority of heavy metals in bed sediments of the Afon Twymyn exist in highly mobile geochemical phases, potentially posing serious threats to ecological integrity. Significant metal flushing occurred during flood events at Dylife mine and a distinct seasonal pattern was observed with greater levels of flushing occurring during flood events in the summer months. It is suggested that investigations of contaminant/ecosystem relations and potential remediation strategies should include high-resolution temporal sampling of river water chemistry under conditions of flood flow. Paradoxically, a range of biological indices failed to identify significant negative impacts of metal mine contaminants on macroinvertebrate communities, suggesting there is little contamination of the river ecosystem. However, Canonical Correspondence Analysis did identify significant differences in community structure between polluted and unpolluted river stretches, suggesting that standard unimetric biological indices might only be successful in identifying impacts at the most severely polluted mine sites. It is suggested that the ecological approach of the European Union Water Framework Directive to the assessment of river ecosystem status may not yield an accurate representation of contamination in rivers such as the Afon Twymyn where contamination by mining is moderate, circum-neutral and the mining operation is long abandoned.
39

A conveniência da implementação da Diretiva Quadro da Água no ordenamento jurídico brasileiro como medida efetiva de justiça ambiental: o caso da exploração do Nióbio em Catalão

Branco Filho, Thelmo de Carvalho Teixeira 09 May 2017 (has links)
Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2017-05-26T12:11:22Z No. of bitstreams: 1 Thelmo de Carvalho Teixeira Branco Filho.pdf: 8694807 bytes, checksum: e1252561376dd05406ca6512edf52d8a (MD5) / Made available in DSpace on 2017-05-26T12:11:22Z (GMT). No. of bitstreams: 1 Thelmo de Carvalho Teixeira Branco Filho.pdf: 8694807 bytes, checksum: e1252561376dd05406ca6512edf52d8a (MD5) Previous issue date: 2017-05-09 / This thesis will address the convenience of implementing the Water Framework Directive (WFD) in the Brazilian legal system, as a measure of effective environmental justice. In line with the focus of this investigation, it is also considered damages, benefits and conflicts that take place in the Municipality of Catalão, State of Goiás, Brazil, where Niobium is extracted. One of the major sources of conflict therein is water, since the extraction of minerals causes the silting of springs, among other problems. This study has the purpose of contributing to the improvement of the regulation and effectiveness of environmental protection, departing from a popular conflict, which basically involves water. This research leads us to contemplate how the pressure related to social conflicts in Catalao has helped to redefine protection strategies that would secure greater effectiveness of environmental laws. The research hypothesis will be grounded on legal and other scientific theories, including environmental, social and legal diagnoses, which ensure the interdisciplinary nature of the study. The methods employed were the case study and the inductive method, since this research relies on specific data on mining exploration in the Municipality of Catalão, although aiming at looking for premises that could be applied wherever this type of activity may occur. We are seeking answers to "how" and/or "why" the social phenomena combined with the legal one are operating. Mineral resources are the passion of the 21st century, since they are closely associated with the technological age and exacerbated consumption. This fact should be observed with caution, since there is a need for concern with future generations, since those are non-renewable goods. The major challenge of the WFD is the access to information, transparency and participation of citizens as well as all stakeholders in the various stages of the decision-making process, as well as the control on diffuse emissions based on best environmental practices, which in Brazil leave to be desired. Consequently, the existence of this tool in national territory will strengthen other institutes such as environmental responsibility, environmental licensing and the use of best available techniques / A presente tese abordará a conveniência da implementação da Diretiva Quadro da Água (DQA), no ordenamento jurídico brasileiro, como medida de efetiva justiça ambiental, bem como a respeito de danos, benefícios e conflitos ocorridos no município de Catalão, Estado de Goiás, onde se extrai o Nióbio, foco desta investigação. Um dos maiores eixos de conflito é a água, já que a extração dos minerais ocasiona o assoreamento de nascentes, dentre outros problemas. Este estudo visa contribuir para melhorar a regulamentação e a eficácia da proteção ambiental, a partir do conflito popular, envolvendo essencialmente a água. O estudo leva-nos a refletir sobre como a pressão e os conflitos sociais em Catalão têm colaborado para redefinir as estratégias de proteção, a fim de garantir maior efetividade às leis ambientais. A hipótese de pesquisa será edificada pelas teorias jurídicas e demais teorias científicas, perpassando por diagnósticos ambientais, sociais e jurídicos, salvaguardando o viés interdisciplinar do estudo. Os métodos utilizados nesta pesquisa serão o estudo de caso e o método indutivo, uma vez que partimos de dados particulares, como a exploração da mineração no município de Catalão, em busca de premissas que possam ser aplicadas onde ocorrer este tipo de atividade. A metodologia será aplicada visando investigar “como” e/ou “por que” os fenômenos sociais agregados aos jurídicos são atuantes. Os recursos minerais são a coqueluche do século XXI, já que estão intimamente ligados à era tecnológica e ao consumo exacerbado, o que deve ser observado com certa cautela, haja vista a preocupação com as futuras gerações e por se tratar de bens não renováveis. O grande desafio da DQA é o acesso à informação, a transparência e a participação dos cidadãos e de todas as partes interessadas nas várias fases do processo de decisão, além dos controles nas emissões difusas baseados nas melhores práticas ambientais, o que no Brasil deixa a desejar. Por conseguinte, a existência desta ferramenta em território nacional reforçará outros institutos como a responsabilidade ambiental, os licenciamentos ambientais e a utilização das melhores técnicas disponíveis
40

Stream monitoring using near-infrared spectroscopy of epilithic material

Persson, Jan January 2007 (has links)
<p>The European Union Water Framework Directive (WFD), with initiatives to manage surface water resources, has increased the need for fast and inexpensive methods for monitoring conditions in streams. The objective of this thesis is to assess the potential of near-infrared spectroscopy (NIRS) of epilithic material to become such method. NIRS, which is a technique that is commonly used in industry for process monitoring and quality control of products, registers the chemical properties of organic material on a molecular level. Epilithic material, i.e. the layer of dead and alive material that covers stone surfaces in streams, is continuously influenced by the stream water that flows over it, and it has the potential to integrate chemical and biological conditions over time. The temporal integration is a significant factor, since conditions in streams can change within hours or days. The thesis consists of two published papers. In the first paper a new sampler for epilithic material, the Stone Brusher, was described and the performance evaluated. The Stone Brusher is designed to take qualitative or semi-quantitative samples of epilithic material from stones at 7–50 cm water depth. The epilithic material is dislodged from the stone surface with a rotating brush enclosed in a chamber, and the material is drawn up directly into the sample bottle with an air-cylinder. The operator takes a sample quickly and without putting hands into the water. The sampler is made of plastic, stainless steel and aluminium and weighs 3.1 kg. It is designed to meet the demand for standardized sampling for research and environmental monitoring and to improve working conditions for sampling personnel. The equipment allows sampling from surfaces of bedrock and large stones that cannot be lifted from the bottom. Using data of near-infrared spectroscopy and diatom analyses, this new sampler was evaluated in comparison to the toothbrush method, a primitive method which is the current standard in EU. The results indicate that the Stone Brusher reduces sampling variability compared with the toothbrush method.</p><p>In the second paper, the Stone Brusher was used to collect epilithic material from 65 sites (42 uncontaminated and 23 contaminated) from streams in the widespread mining area called the Skellefte-district in Västerbotten, northern Sweden, in order to test the hypothesis that impact on the epilithic material caused by emissions from mining and mining-related industries can be detected using NIRS. The epilithic material was filtered onto glass fibre filters, measured by NIRS, and the results were modelled using Principal Component Analysis (PCA). The NIRS approach was evaluated by comparing it with the results of chemical and diatom analyses of the same samples. Based on PCA, the NIRS data distinguished contaminated from uncontaminated sites and performed slightly better than chemical analyses and clearly better than diatom analyses. Of the streams designated a priori as contaminated, 74 % were identified as contaminated by NIRS, 65 % by chemical analysis and 26 % by diatom analysis. Unlike chemical analyses of water or of epilithic material samples, NIRS data reflect biological impacts in the streams. Given that, and the simplicity of NIRS-analyses, further studies to assess the use of NIRS of epilithic material are justified. NIRS has the potential to become a fast method for screening in regions where large numbers of streams occur to find impacted streams or as a routine method for temporal monitoring in selected streams for early detection of environmental impact, similar to process monitoring in industry.</p>

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