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Glufosinat: Metabolismus in transgenen und nicht-transgenen Pflanzengeweben sowie Schicksal im Boden

Das Projekt "Glufosinat: Metabolismus in transgenen und nicht-transgenen Pflanzengeweben sowie Schicksal im Boden" wird vom Umweltbundesamt gefördert und von RWTH Aachen University, Institut für Umweltforschung, Biologie V, Lehrstuhl für Umweltbiologie und -chemodynamik durchgeführt. Glufosinat (oder Phosphinotricin) ist ein vergleichsweise modernes Herbizid, das seit etwa 25 Jahren in Gebrauch ist. Bei der Verbindung handelt es sich um eine Aminosäure; üblicherweise bezeichnet man das DL-Racemat als Glufosinat, das L-Enantiomer als Phosphinothricin. Die Verbindung ist Teilstruktur eines von den Pilzen Streptomyces viridochromogenes und Streptomyces hygroscopicus produzierten natürlichen Antibiotikums (Tripeptid: L-Alanin-L-Alanin-L-Phosphinothricin). Neben seiner antibakteriellen Wirkung zeigt Glufosinat eine nicht-selektive herbizide Wirkung. Der antibakterielle und herbizide Effekt geht nur vom L-Enantiomer aus; das D-Enantiomer ist inaktiv. Sowohl Glufosinat (Racemat) als auch das Tripeptid (Bialaphos oder Bilanaphos; mit L-Enantiomer) werden als Herbizide vermarktet. Die herbizide Wirkung von Phosphinothricin beruht auf einer Inhibition der Glutaminsynthetase. Glufosinat weist günstige ökotoxikologische Eigenschaften auf, z.B. bezüglich Versickerung, Abbau sowie Toxizität gegenüber Tier und Mensch. Auf Grund dieser Eigenschaften ist Glufosinat ein geeigneter Kandidat zur Herstellung gentechnisch modifizierter Herbizid-resistenter Pflanzen, um Glufosinat auch selektiv - im Nachauflauf - einsetzen zu können. Dazu wurden verschiedene Spezies, wie z.B. die Zuckerrübe, mit dem bar-Gen aus Streptomyces hygroscopicus transformiert. Das bar-Gen codiert für eine Phosphinothricin-N-acetyltransferase, die Phosphinothricin zum nicht herbizid-wirksamen, stabilen N-Acetylderivat umsetzt. Bei entsprechend hoher Expression des bar-Gens resultiert eine Glufosinat-resistente Pflanze. Ein Ziel unseres Forschungsvorhabens war es, den Metabolismus von Glufosinat und der einzelnen Enantiomere (L- und D-Phyosphinothricin) in transgenen und nicht transgenen Pflanzenzellkulturen zu untersuchen. Die transgenen Kulturen, die von der Zuckerrübe (Beta vulgaris) stammten, waren mit dem bar-Gen transformiert, exprimierten demnach die Phosphinothricin-N-acetyltransferase. Sie wurden aus entsprechenden Sprosskulturen initiiert. Daneben wurden nicht-transgene Kulturen von Zuckerrübe, Karotte (Daucus carota), Fingerhut (Digitalis purpurea) und Stechapfel (Datura stramonium) untersucht. In einer zweiten Versuchsserie wurden abgetrennte Sprosse und Blätter von 20 Wildpflanzen auf den Metabolismus von Glufosinat untersucht. Es sollte überprüft werden, ob qualitative und quantitative Unterschiede im Umsatz des Herbizids im Pflanzenreich vorkommen und möglicherweise eine natürliche (teilweise) Resistenz gegenüber Glufosinat existiert. Schließlich wurde das Schicksal des Herbizids im Boden (Abbau, Versickerung) nach Aufbringung des Wirksstoffs in einer handelsüblichen Formulierung auf ein bewachsenes Versuchsfeld im Freiland untersucht.

European Union Basin-scale Analysis, Synthesis and Integration (EURO-BASIN)

Das Projekt "European Union Basin-scale Analysis, Synthesis and Integration (EURO-BASIN)" wird vom Umweltbundesamt gefördert und von Danmarks Tekniske Universitet durchgeführt. Objective: EURO-BASIN is designed to advance our understanding on the variability, potential impacts, and feedbacks of global change and anthropogenic forcing on the structure, function and dynamics of the North Atlantic and associated shelf sea ecosystems as well as the key species influencing carbon sequestering and ecosystem functioning. The ultimate goal of the program is to further our capacity to manage these systems in a sustainable manner following the ecosystem approach. Given the scope and the international significance, EURO-BASIN is part of a multidisciplinary international effort linked with similar activities in the US and Canada. EURO-BASIN focuses on a number of key groups characterizing food web types, e.g. diatoms versus microbial loop players; key species copepods of the genus Calanus; pelagic fish, herring (Clupea harengus), mackerel (Scomber scombrus), blue whiting (Micromesistius poutassou) which represent some of the largest fish stocks on the planet; piscivorous pelagic bluefin tuna (Thunnus thynnus) and albacore (Thunnus alalunga) all of which serve to structure the ecosystem and thereby influence the flux of carbon from the euphotic zone via the biological carbon pump. In order to establish relationships between these key players, the project identifies and accesses relevant international databases and develops methods to integrate long term observations. These data will be used to perform retrospective analyses on ecosystem and key species/group dynamics, which are augmented by new data from laboratory experiments, mesocosm studies and field programs. These activities serve to advance modelling and predictive capacities based on an ensemble approach where modelling approaches such as size spectrum; mass balance; coupled NPZD; fisheries; and ?end to end? models and as well as ecosystem indicators are combined to develop understanding of the past, present and future dynamics of North Atlantic and shelf sea ecosystems and their living marine resources.

Sub project: Mass transfer, aging and reactions at NAPL interfaces in porous media

Das Projekt "Sub project: Mass transfer, aging and reactions at NAPL interfaces in porous media" wird vom Umweltbundesamt gefördert und von Universität Tübingen, Zentrum für Angewandte Geowissenschaften - Umweltmineralogie und Umweltchemie durchgeführt. Release of non-aqueous phase liquids (NAPLs) into natural porous media is a widespread environmental problem. Transfer of pollutants across the NAPL-water phase boundary determines both the extent of groundwater contamination as well as the persistence of residual NAPL phases in porous media. Previous research has shown that NAPL-water interfaces are subject to 'aging' phenomena in aqueous environments, e.g., development of skin-like viscous films. However, surprisingly litte is known about the factors and mechanisms that control such film formation of NAPLs in aqueous porous media and about the effects of such films on mass transfer of organic contaminants from the NAPL to the aqueus phase. In the proposed project we will address these knowledge gaps in order to (i) achieve a process based understanding of reactions and environmental conditions leading to the formation of viscous phase boundaries of NAPLs in porous media (aging) and to (ii) develop and vali-date a physical model of such boundary layers to quantify time-dependent interfacial phenomena in multi-component NAPL-water systems (mass transfer). To this end we will carry out batch and flow-through experiments with model and real NAPLs in water and aqueous porous media and make intense use of chemical probe techniques. We will utilize chemical and rheological analysis, microscopic process modeling and, in cooperation with partners within the research group, we will apply new designs of spectroscopic and electrochemical tools for spatially highly resolved investigations of the interface as well as contribute to reactive transport modeling at NAPL-contaminated porous media.

Towards a Guideline for Digital Soil Mapping in Ecuador

Das Projekt "Towards a Guideline for Digital Soil Mapping in Ecuador" wird vom Umweltbundesamt gefördert und von Universität Bayreuth, Abteilung Bodenphysik durchgeführt. Research experience in digital soil mapping (DSM) shall be extended and deepened in two further research areas in order to develop a guideline for DSM in Ecuador. The guideline will give an overview: a) about the DSM approach, b) the different sampling designs developed according to the area size, accessibility and terrain complexity, c) the various methods from the field of supervised machine learning to develop digital soil maps, and d) the implementation with open source software. The soil-landscapes of the three investigation areas will be analysed and soil-landscape models will be developed by supervised machine learning techniques, in order to spatially predict soil properties from point data based on environmental prediction parameters. By using the so developed digital soil maps as principal input, a functional soil-landscape analysis is carried out to determine landslide, erosion and anthropogenic disturbance risk zones as well as estimate the soil organic carbon stocks and soil fertility.

Scenarios of the Global Water System

Das Projekt "Scenarios of the Global Water System" wird vom Umweltbundesamt gefördert und von Universität Kassel, Center for Environmental Systems Research durchgeführt. The global water system is undergoing significant changes in its physical, chemical and biological characteristics, as well as in its human dimensions. The transformations currently taking place in the system raise key scientific questions: Will these changes continue at their current pace and intensity over the coming decades? If so, what impact will they have on nature and society? Researchers have begun addressing these questions through a growing number of comprehensive scenario studies that examine future trends in water resources from the continental and global perspectives. The first objective of this one year project is to review and appraise the existing body of global water scenarios in order to extract out important scientific insights, identify gaps and shortcomings, and derive scientific procedures for developing a new generation of global water scenarios. The second objective is to carry-out model experiments with an existing model to produce new continental scale water scenarios for Africa that address some of the deficits of current global water scenarios. The new scenarios will advance previous continental/global scenarios by simultaneously taking into account the effect of changing land use, climate and socioeconomic factors on future water use and water availability. Africa is selected as a case study for these model experiments because of the particularly significant changes it is experiencing in its freshwater system. To ensure that the information and perspectives of developing countries are taken into account, the principal investigator proposes to spend 7 months out of the 12-month project at the University of Stellenbosch in South Africa (residing at this university will provide advantages such as access to a network of African water researchers). It is critical for the German research community, especially researchers working on international and global-scale scientific problems, to develop stronger ties with the scientific community in developing countries. This project will provide direct scientific input to the Global Water System Project of the Earth System Science Partnership, as well as the World Water Development Report being prepared by a consortium of UN water-related organizations. This is an eigenständiges Projekt within the framework of the Global Water System Project of which the Antragssteller is Co-Chairman. It is expected that the evaluation of scenarios will make a major contribution to anticipating future changes in the global water system.

Hydrogen for clean urban transport in Europe (HyFleet:CUTE)

Das Projekt "Hydrogen for clean urban transport in Europe (HyFleet:CUTE)" wird vom Umweltbundesamt gefördert und von Mercedes-Benz Group AG durchgeführt. Im Projekt HyFLEET:CUTE wurde 47 Busse in 10 Städten auf drei Kontinenten eingesetzt (Amsterdam, Barcelona, Berlin, Hamburg, London, Luxemburg, Madrid, Perth, Peking und Reykjavik). Das Projekt zielte darauf ab, Antriebskonzepte für Stadtbusse zu demonstrieren und weiterzuentwickeln, die Wasserstoff als Kraftstoff nutzen. Ferner wurden die damit einhergehenden Produktions- und Verteilungspfade für nachhaltig erzeugten Wasserstoff erprobt. Durch die Entwicklung verbrauchsoptimierter Wasserstoffbusse hat das Projekt dazu beigetragen, den Energieverbrauch im Transportsektor zu reduzieren und zu diversifizieren. Obendrein konnte es Wege einer sauberen, effizienten und sicheren Wasserstoffversorgung und -verteilung vermitteln. Von den eingesetzten Bussen besaßen 33 einen Elektromotor, der mit Strom aus einer Brennstoffzelle angetrieben wurde. Die anderen 14 Busse hatten einen Verbrennungsmotor, der an den Kraftstoff Wasserstoff angepasst war. Im Laufe des Projekts wurde ferner ein neuer Brennstoffzellen-Hybrid-Bus entwickelt, getestet und im Alltagsbetrieb demonstriert. Weiteres Kernelement des Projektes war die Optimierung der bestehenden Wasserstoff-Infrastrukturen, die aus dem Vorläuferprojekt CUTE stammten, sowie die Entwicklung und Erprobung neuer Anlagen und Versorgungskonzepte. Der Wasserstoff wurde an den einzelnen Standorten auf verschiedene Weise bereitgestellt: in manchen Städten durch Herstellung direkt an der Tankstelle ('on site) mittels Elektrolyse oder Reformierung, in anderen Städten per Lkw aus externer Produktion. So konnten verschiedene Pfade der Produktion und Verteilung bewertet werden. HyFLEET:CUTE umfasste außerdem den Betrieb von zwei stationären Brennstoffzellen, die an der Tankstelle in Berlin elektrischen Strom und Wärme bereitstellten. In HyFLEET:CUTE haben 31 Partner aus Politik, Industrie und Wissenschaft kooperiert, um die Entwicklung der Wasserstofftechnologie voranzubringen. Das Projekt war auch Teil der Initiative 'Wasserstoff für Mobilität (Hydrogen for Transport), die alle verkehrsbezogenen Demonstrationsvorhaben der Europäischen Kommission in diesem Bereich beraten und koordiniert hat. Die Aufgaben von PLANET PLANET war für die Bewertung der Leistungsfähigkeit der Wasserstoff-Tankstellen verantwortlich und konnte so an die erfolgreichen Arbeiten im Vorgängerprojekt CUTE anschließen. Zu den wichtigsten Indikatoren, die aus den täglichen Betriebsdaten der 10 Standorte zu ermitteln waren, gehörten Wirkungsgrade und Verfügbarkeiten. Daraus wurden die 'kritischen Komponenten ermittelt, die z.B. an mehreren Standorten bzw. wiederholt zu Ausfallzeiten führten. In Zusammenarbeit mit den Projektpartnern wurden Maßnahmen zur Optimierung entwickelt und Empfehlungen für zukünftige Systeme abgeleitet. PLANET leitete ferner die weltweiten Aktivitäten für Aus- und Weiterbildung. Ziel war es, die Ergebnisse und Erfahrungen aus HyFLEET:CUTE an potentielle Nutzergruppen weitezugeben. usw.

Sub-seabed CO2 Storage: Impact on Marine Ecosystems (ECO2)

Das Projekt "Sub-seabed CO2 Storage: Impact on Marine Ecosystems (ECO2)" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum für Ozeanforschung Kiel (GEOMAR) durchgeführt. Objective: The ECO2 project sets out to assess the risks associated with the storage of CO2 below the seabed. Carbon Capture and Storage (CCS) is regarded as a key technology for the reduction of CO2 emissions from power plants and other sources at the European and international level. The EU will hence support a selected portfolio of demonstration projects to promote, at industrial scale, the implementation of CCS in Europe. Several of these projects aim to store CO2 below the seabed. However, little is known about the short-term and long-term impacts of CO2 storage on marine ecosystems even though CO2 has been stored sub-seabed in the North Sea (Sleipner) for over 13 years and for one year in the Barents Sea (Snhvit). Against this background, the proposed ECO2 project will assess the likelihood of leakage and impact of leakage on marine ecosystems. In order to do so ECO2 will study a sub-seabed storage site in operation since 1996 (Sleipner, 90 m water depth), a recently opened site (Snhvit, 2008, 330 m water depth), and a potential storage site located in the Polish sector of the Baltic Sea (B3 field site, 80 m water depth) covering the major geological settings to be used for the storage of CO2. Novel monitoring techniques will be applied to detect and quantify the fluxes of formation fluids, natural gas, and CO2 from storage sites and to develop appropriate and effective monitoring strategies. Field work at storage sites will be supported by modelling and laboratory experiments and complemented by process and monitoring studies at natural CO2 seeps that serve as analogues for potential CO2 leaks at storage sites. ECO2 will also investigate the perception of marine CCS in the public and develop effective means to disseminate the project results to stakeholders and policymakers. Finally, a best practice guide for the management of sub-seabed CO2 storage sites will be developed applying the precautionary principle and valuing the costs for monitoring and remediation.

Sub project: MIneral dust variability in the Southern Ocean (MISO)

Das Projekt "Sub project: MIneral dust variability in the Southern Ocean (MISO)" wird vom Umweltbundesamt gefördert und von Max-Planck-Institut für Meteorologie durchgeführt. Polar ice cores represent the only direct archive for the deposition of aeolian dust particles in the past, with mineral dust being transported over long-distances from desert regions to the polar ice sheets. While the total dust deposition is a first order measure of dust mobilization, hence climate conditions in the dust source regions, particle size distributions allow for a quantification of transport efficiency. Here we will combine latest Antarctic dust records from the EPICA ice core from Dronning Maud Land and a coupled state-of-the art Global Climate model (ECHAM5) with an implicit aerosol scheme (HAM) to quantify paleoclimatic changes in dust mobilization, transport and deposition. High-resolution ice core dust analysis on atmospheric dust concentration and particle size distribution will be performed for selected time slices in the Holocene, MIS 5.5 and during the transition into the warm periods in parallel to time slice model runs. Appropriate boundary conditions for the high simulation atmosphere only simulations will be taken from long simulations with an earth system model. In return the effect of dust on past climate changes will be assessed. The time scales addressed by both model and ice core data range from seasonal changes, interannual variability to long-term changes in dust mobilization and transport, constraining potential dust source regions and their temporal changes as well as spatiotemporal variability in Circumantarctic circulation patterns.

Sub project: Seismic site characterization of the proposal ICDP drilling project in the Baza Basin (Southern Spain)

Das Projekt "Sub project: Seismic site characterization of the proposal ICDP drilling project in the Baza Basin (Southern Spain)" wird vom Umweltbundesamt gefördert und von Helmholtz-Zentrum Potsdam Deutsches GeoForschungsZentrum durchgeführt. The intra-mountain Baza Basin in Southern Spain is the largest of the Late Neogene continental basins of the Betic Cordillera. It provides an up to 2.5 km thick archive of lacustrine and ancillary continental deposits from the Late Miocene to Middle Pleistocene. Infilling of the Baza Basin proceeded mainly by deposition of fine-grained deposits arranged in concentric facies belts in a lake complex. The expansion and contraction of these nested paleoenvironments serve as highly sensitive indicators of climate change which makes the Baza Basin a unique site for an integrated paleoclimate-oriented study of the last 7Ma of SE Europe. The planned LARSEI drilling project (LAcustrine Record of SE Iberia; submitted pre-proposal to ICDP) proposes to drill the Baza evaporitic basin in order to establish a realistic paleo-climatic record through the final Neogene (including the entire Pliocene) that very likely reflects regional events in the western Mediterranean as well as global climate milestones. Prerequisite for the drilling activities is the profound knowledge of the basin structure and local zones of neo-tectonic deformation, mainly related to the Baza fault bounding the basin to the West. We propose to aquire seismic multichannel profiles providing high-resolution images of the basin and related structural units (i.e. faults). The results of these measurements will both help to guide the drilling activities (including drilling site selection; presite study) and to better understand the structure and evolution of the Baza basin.

Biomass Fuell Cell Utility System (BIOCELLUS)

Das Projekt "Biomass Fuell Cell Utility System (BIOCELLUS)" wird vom Umweltbundesamt gefördert und von Technische Universität München, TUM School of Engineering and Design, Fakultät für Maschinenwesen, Lehrstuhl für Energiesysteme durchgeführt. Objective: Energy from Biomass needs highly efficient small-scale energy systems in order to achieve cost effective solutions for decentralized generation especially in Mediterranean and Southern areas, and for applications without adequate heat consumer. Thus fuel cells are an attractive option for decentralized generation from biomass and agricultural residues but they have to meet at least two outstanding challenges: 1. Fuel cell materials and the gas cleaning technologies have to treat high dust loads of the fuel gas and pollutants like tars, alkalines and heavy metals. 2. The system integration has to allow efficiencies of at least 40-50 percent even within a power range of few tens or hundreds of kW. This proposal addresses in particular these two aims. Hence the first part of the project will focus on the investigation of the impact of these pollutants on degradation and performance characteristics of SOFC fuel cells in order to specify the requirements for appropriate gas cleaning system (WP 1-2). These tests will be performed at six existing gasification sites, which represent the most common and applicable gasification technologies. WP 3 will finally test and demonstrate the selected gas cleaning technologies in order to verify the specifications obtained from the gasification tests. The results will be used for the development, installation and testing of an innovative SOFC - Gasification concept, which will especially match the particular requirements of fuel cell systems for the conversion of biomass feedstock. The innovative concept comprises to heat an allothermal gasifier with the exhaust heat of the fuel cell by means of liquid metal heat pipes. Internal cooling of the stack and the recirculation of waste heat increases the system efficiency significantly. This so-called TopCycle concept promises electrical efficiencies of above 50 percent even for small-scale systems without any combined processes.

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