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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.
11

Flood control at multipurpose reservoirs considering downstream hazards and water quality

Pohl, Reinhard January 2010 (has links)
Model-based reservoir management systems are indispensable for determining an optimal water resources management in river basins with multipurpose reservoirs. A recently developed management system will be described, using evolutionary algorithms to optimize both event-based and long-term operation of a reservoir system concerning multiple objectives with different units of measurement (Money, Dimensions, Ecology). The result are sets of so-called Pareto optimal solutions which represent the most useful compromises and can serve as a transparent information base for decision-making. In order to improve the ecological performance of multipurpose reservoirs, a dynamic operating scheme is implemented, which ensures that reservoir releases correspond to natural flow variability as far as possible. In addition water quality problems during the flood discharge and the release from selected layers of the water body will be discussed in brief.
12

Fließgewässerorganismen und Eisen

Kruspe, Rainer, Neumann, Jürgen, Opitz, Michael, Theiss, Susanne, Uhlmann, Wilfried, Zimmermann, Kai 28 April 2015 (has links) (PDF)
Durch den Grundwasserwiederanstieg in einigen Bereichen des Sanierungsbergbaus in der Lausitz gelangt saures und eisenhaltiges Grundwasser in die Oberflächengewässer. Die Oxidation des Eisens führt zu einer sichtbaren Braunfärbung der Gewässer. Die Eisenhydroxidschlämme lagern sich auf dem Gewässersediment und an Bauwerken ab. Dabei sind negative Auswirkungen auf die Biozönose und die Morphologie des Fließgewässers zu erwarten. Die Broschüre basiert auf einer Studie im Rahmen des Projektes VODAMIN. Durch statistische Aufbereitung wurden Effektkonzentrationen bestimmt, die einen möglichen Zusammenhang zwischen ansteigenden Eisenkonzentrationen und sich reduzierender Artenvielfalt im Fließgewässer darstellen.
13

Maßnahmenumsetzung WRRL in Sachsen

21 January 2013 (has links) (PDF)
Nach der Europäischen Wasserrahmenrichtlinie sollen Ende 2015 die Oberflächengewässer und das Grundwasser einen »guten Zustand« aufweisen. Der Bericht informiert zum Stand der Maßnahmen und ihrer Umsetzung in Sachsen für die Bereiche Landwirtschaft und Wasserwirtschaft. Er verdeutlicht, dass die Maßnahmenprogramme nur dann erfolgreich umgesetzt werden können, wenn zur Erreichung der Bewirtschaftungsziele auch alle relevanten Qualitätskomponenten in ihrem Zusammenwirken betrachtet werden.
14

Phytoplankton community structure and water quality of Red River, Vietnam / Cấu trúc quần xã thực vật nổi và chất lượng nước sông Hồng, Việt Nam

Duong, Thi Thuy, Le, Thi Phuong Quynh, Ho, Tu Cuong, Vu, Thi Nguyet, Hoang, Thi Thu Hang, Dang, Dinh Kim, Lu, Xixi 25 August 2015 (has links) (PDF)
This study aimed to describe the distribution and relative abundance of the phytoplankton obtained during the two seasons (rainy and dry seasons) from the Red river system. The water and phytoplankton samples were monthly collected during the year 2012 at four sampling stations along the Red River (Yen Bai, Vu Quang Hoa Binh,and Ha Noi) . Environmental variables (e.g. temperature, dissolved oxygen, pH, suspended solids, conductivity, TDS, NO3­-N, NH4­-N, PO4-P, Total Phosphorus; and DOC) and phytoplankton (e.g. cell density and relative abundant species) were analyzed. Six phytoplankton classes were identified with the Bacillariophyceae dominating in the phytoplankton community. A distinct seasonal variation in phytoplankton structure was observed with high cells density in dry season and low values in rainy season. PCA (Principal Component Analysis) showed that suspended solid factor that governed the temporal and spatial distribution of phytoplankton structure in the Red River system. / Nghiên cứu này trình bày sự phân bố và độ phong phú tương đối của quần xã thực vật nổi vào mùa mưa và mùa khô trong hệ thống sông Hồng. Các mẫu nước và thực vật nổi được thu hàng tháng trong năm 2012 tại 4 điểm trên sông Hồng (Yên Bái, Vụ Quang, Hòa Bình và Hà Nội). Các thông số môi trường (nhiệt độ, lượng oxy hòa tan, pH, chất rắn lơ lửng, độ dẫn, TDS, NO3-N, NH4-N, PO4-P, T-P và DOC) và thực vật phù du (mật độ tế bào,độ phong phú tương đối ) đã được phân tích. Sáu lớph tảo được được xác định với tảo silíc chiếm ưu thế trong quần xã thực vật phù du. Sinh khối thực vật đạt giá trị cao vào mùa khô trong khi thấp vào mùa mưa. Phân tích hợp phần chính cho thấy yếu tố chất rắn lơ lửng đóng vai trò quan trọng việc xác định biến động thời gian và không gian cấu trúc quần xã thực vật nổi trong hệ thống sông Hồng.
15

A management system to optimize reservoir control in the case of floods

Pohl, Reinhard, Bornschein, Antje 11 February 2015 (has links) (PDF)
Many multipurpose reservoirs are situated in the low mountain range of Germany. Most of them are necessary for drinking water supply and flood protection as well. Other utilizations are recreation, water power and the downstream low water regulation during dry seasons. The operation rules of the reser-voirs have to be optimized to meet the different requirements of use. One tool within this framework is a management system for river basins including all reservoirs and their specific operation rules affecting the downstream reaches. As an optimization objective for instance the minimization of inundation risks can be defined. In this case the risk can be defined as hydraulic and hydrologic safety of the reservoir itself and the risk due to inundation and damaging in the downstream regions. Considering the European Water Framework Directive the ecological aspect of reservoir management is one more point in the optimization process. To es-tablish a pilot project the software TALSIM will be applied to river catchments in the ore mountains (Saxony).
16

Gewässerzustandsbewertung nach EU-WRRL – Teil Fische

Völker, Fabian, Gause, Sven 01 June 2015 (has links) (PDF)
Umsetzung der Europäischen Wasserrahmenrichtlinie (EU-WRRL) für die Qualitätskomponente Fischfauna in Sachsen
17

Gewässerzustandsbewertung nach EU-WRRL – Teil Fische

01 June 2015 (has links)
No description available.
18

Jahresbericht ... zur fischereilichen Bewertung der Oberflächenwasserkörper in Sachsen nach WRRL

Signer, Jean 01 June 2015 (has links) (PDF)
Umsetzung der Europäischen Wasserrahmenrichtlinie (EU-WRRL) für die Qualitätskomponente Fischfauna in Sachsen
19

Jahresbericht ... zur Befischung im Rahmen der EU-WRRL

Völker, Fabian, Volkmann, Sven 01 June 2015 (has links) (PDF)
Umsetzung der Europäischen Wasserrahmenrichtlinie (EU-WRRL) für die Qualitätskomponente Fischfauna in Sachsen
20

Befischung sächsischer Fließgewässer im Rahmen der EU-WRRL

Völker, Fabian, Volkmann, Sven 01 June 2015 (has links) (PDF)
Umsetzung der Europäischen Wasserrahmenrichtlinie (EU-WRRL) für die Qualitätskomponente Fischfauna in Sachsen

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