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Nutzen-Kosten-Untersuchung fuer eine Vertiefung der Unterelbe (Seewaertige Zufahrt fuer den Hamburger Hafen)

Das Projekt "Nutzen-Kosten-Untersuchung fuer eine Vertiefung der Unterelbe (Seewaertige Zufahrt fuer den Hamburger Hafen)" wird vom Umweltbundesamt gefördert und von Planco Consulting GmbH durchgeführt. Untersuchung der regional- und gesamtwirtschaftlichen Wirkungen einer verbesserten seewaertigen Anbindung des Hamburger Hafens ; Zusammenhaenge zwischen Hafenumschlag und regionaler Beschaeftigung.

Eozäne und oligozäne Diatomeen-Vergesellschaftungen limnischer Ablagerungen Deutschlands

Das Projekt "Eozäne und oligozäne Diatomeen-Vergesellschaftungen limnischer Ablagerungen Deutschlands" wird vom Umweltbundesamt gefördert und von Senckenbergische Naturforschende Gesellschaft, Forschungsinstitut und Naturmuseum Senckenberg durchgeführt. Limnische Kieselgur-Sedimente spielen eine wichtige Rolle bei der Entstehung und der Überlieferung tertiärer Fossillagerstätten. Diese extrem feinkörnigen Sedimente bieten ideale Voraussetzungen für die Einbettung und Erhaltung höherer Pflanzen- und Tierreste. Anhand der autochthonen kieseligen Mikrofossil-Vergesellschaftungen lassen sich hochauflösende Rückschlüsse auf Fazies, Ökologie und Klima der Fossilfundstätte ziehen. Massenvorkommen kieseliger Mikroorganismen sind in der Regel an SiO2-reiche Gewässer gebunden, die typisch für das tropische, bzw. subtropische Klima im Tertiär sind. Bei der Verwitterung silikatischer Gesteine und insbesondere verglaster Vulkanite geht die entsprechende Kieselsubstanz in Lösung und kann von Mikroorganismen verwertet werden. Der überwiegende Teil der bislang bekannten tertiären Kieselgur-Lagerstätten scheint an vulkanische Depressionen gebunden zu sein. Die ältesten und mit Sicherheit nachweisbaren limnischen Kieselgur-Sedimente Deutschlands stammen aus dem Mittel-Eozän von Eckfeld (Eifel) und Groß-Zimmern (bei Messel). Ein weiteres Eozän-Vorkommen (Grube Prinz von Hessen, bei Messel) läßt eine vergleichbare Sedimentzusammensetzung erwarten. Diese bislang nicht näher untersuchten, bzw. unbekannten Diatomeen-Floren sollen in Bezug auf Systematik und paläoökologische Aussagen bearbeitet und mit Material von Enspel, einem oberoligozänen Maar-See, verglichen werden.

Überwinterungsstrategien polarer Copepoden: Physiologische Kontrollmechanismen und Auftriebsregulation durch Ammonium

Das Projekt "Überwinterungsstrategien polarer Copepoden: Physiologische Kontrollmechanismen und Auftriebsregulation durch Ammonium" wird vom Umweltbundesamt gefördert und von Universität Bremen, Fachbereich 2 Biologie,Chemie, Marine Zoologie durchgeführt. Ontogenetic seasonal migration associated with a diapause is known as an adaptation to escape temporally from an unfavourable environment in several calanoid copepod species in Polar Seas. Diapausing copepods reside for several months in greater depths where they are presumably neutrally buoyant. Ammonium buoyancy as been observed in several marine invertebrates has never been studied in diapausing copepods. Dependent on the pH, ammonia exists in solutions as both NH3 and NH4 +). Due to the toxicity and the higher diffusibility of NH3 a low haemolymph pH is required to favour the formation of ammonium (NH4 +). The trigger (onset, duration, termination) of diapause is yet unknown. In a recent study we detected ammonium values as high as 500 mmol L-1 in the haemolymph of the diapausing Antarctic copepods Calanoides acutus and Rhincalanus gigas, as well as in the diapausing calanoid copepods Calanoides carinatus and Eucalanus sp. in the Benguela Current upwelling system, indicating ammonia buoyancy in these species. In diapausing copepods metabolic depression is evident by reduced metabolic rate and reduced swim activity. We hypothesize that a low extracellular pH in the haemolymph of diapausing copepods necessary to form NH4 + and to prevent it from diffusive loss could play a fundamental role in the regulation of metabolic depression and thus in the control of diapause. This would lead to a seasonality of ammonia buoyancy with high ammonium and low pHe during diapause and high pHe and low ammonium in the active periods.

Instabilities in alpine Permafrost: strength and stiffness in a warming thermal regime

Das Projekt "Instabilities in alpine Permafrost: strength and stiffness in a warming thermal regime" wird vom Umweltbundesamt gefördert und von Eidgenössische Technische Hochschule (ETH) Zürich, Institut für Geotechnik durchgeführt. Global climate change in cryogenic regions has dominated the research agenda recently, as investigators seek ways of identifying the hazards to infrastructure in cold regions to establish distinct uncertainties through a risk based consideration of sensitivity and consequences and thereby mitigate the risk of permafrost degradation. The latest IPCC report states that temperature increased at the top of the permafrost layer in the Arctic by up to 3 C since the 1980s. The permafrost base has been thawing at rates of up to 0.04 m/yr, permafrost degradation is causing changes in land surface characteristics and drainage systems and snow cover has decreased in most regions. This has been greatest at lower elevations, e.g. in Switzerland. Melting massive ice or degrading permafrost is becoming increasingly susceptible to causing initiation of slope instabilities and debris flows, having caused the 1997 Val Pola debris flows in the Italian Alps. Recent instabilities in the Vallée du Du Durnand in Valais and the Bérard Rock Glacier in France, both in 2006, emphasise the growing concern. Clear risks were also identified in Turtmanntal, Val d'Anniviers and Mattertal, where some rock glacier features indicated formation of crevasses and depressions at critical positions in the landform and increased risk of failure through the body of the mountain permafrost. Knowledge of the evolving thermal state and internal structure, as well as the response of permafrost soils to a gradual warming cycle, is necessary. This project focuses on the variations of geotechnical response of Alpine permafrost with time and temperature. The time effects are important, since a rock glacier will flow or creep downhill. Landforms have changed in the smaller rock glaciers in the West Alps, where these are particularly sensitive to warming scenarios. Clearly this may lead to instability. The specific goals are: o to investigate artificially frozen soils in the laboratory to understand the relative influences of stresses, soil-ice content, particle size and shape, strain rate and temperature on the strength and stiffness, particularly within the thawing zone, o to obtain equivalent strength and stiffness data from stored (and future) cored samples of Alpine Permafrost and to compare with those from artificial frozen soil, o to establish relationships between key parameters for both artificial and real mountain permafrost, o to test an existing constitutive law to represent the thermo-hydro-mechanical behaviour of Alpine permafrost, o to obtain relevant parameters for future input to the constitutive model and subsequent numerical analysis of the test data.

Innovation of noise barriers: Improved noise abatement for motorways and railway tracks (CALM TRACKS AND ROUT)

Das Projekt "Innovation of noise barriers: Improved noise abatement for motorways and railway tracks (CALM TRACKS AND ROUT)" wird vom Umweltbundesamt gefördert und von CALMA - Tec Lärmschutzsysteme GmbH durchgeführt. Objective: The European Parlament and Council has established new standards of tolerance versus traffic noise: reduction of dB(A) to current standards. To meet these improved environmental standards, more effective noise barriers are requested, better noise abatement technologies, new absorptive materials and higher sound screens, eventually tunnels will be necessary. Noise harassment is widely the cause of mental depression and physical exhaustion of people. It is one of the biggest challenge of human sanity in towns and country. Our project is dealing with noise protection walls with improved noise shielding abilities through special shaping and new absorptive qualities of material and construction. Objectives: To achieve essential improvements of the shielding performance, acoustic quality and psycho-acoustic performance and innovative design of noise barriers are objectives of this project. Building up on the so far reached innovation and improved effect, we want to: - Focus on further development of innovative designs, constructions, materials and effects increasing the shielding efficiency of noise barriers. - Study acoustic phenomena of, and inside sound barriers in theory and practical application. - Scientific evidence of the refraction edge performance of different shapes, materials and dimensions: extinction and/or modulation of noise by interference. - Search and evaluate new materials and surfaces (introducing nanotechnology) in their absorbtive or interference behaviour. - Create and evaluate new designs: optical appearance and attractive design - Psycho-acoustic performance: less and friendly noise sensation. - Rigid function within overall road and track design; heavy duty, high durability, climatic resistance, shock resistance and crash performance.

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