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Sonderforschungsbereich (SFB) 607: Wachstum oder Parasitenabwehr? Wettbewerb um Ressourcen in Nutzpflanzen aus Land- und Forstwirtschaft, Teilprojekt B1: Allometrie und Raumbesetzung von krautigen und holzigen Pflanzen. Integration von Pflanzen- und Bestandesebene

Das Projekt B1 'Allometrie und Raumbesetzung von krautigen und holzigen Pflanzen' ist Teil des Sonderforschungsbereiches 607 Wachstum und Parasitenabwehr und befindet sich bereits in der vierten Phase des seit 1998 laufenden Forschungsprojektes. Bisher wurde im Projekt B1 die Allometrie als Resultat der pflanzeninternen Steuerung der Allokation untersucht. Auf Individuenebene wurden Allometrie und ihre Veränderung für verschiedene Baumarten in verschiedenen ontogenetischen Stadien untersucht. Auf Bestandesebene wurden die self-thinning-Linien von Yoda und Reineke für krautige bzw. holzige Pflanzenbestände analysiert. Bisherige Allometriebestimmungen erbrachten für diese Arten zwar ähnliche Größenordnung aber auch charakteristische Unterschiede, die Ausdruck spezifischer Strategien der Raumbesetzung und -ausbeutung widerspiegeln. Die bisher vereinzelten Auswertungen sollen in Phase IV in eine übergreifende Analyse (versch. Arten, ontogenetische Stadien, Konkurrenzsituationen, Störfaktoren) der Allometrie auf Pflanzen- und Bestandesebene münden.

Hydrogeological and hydrochemical modelling of density-driven flow in the Tiberias Basin, in particular between Ha'on and Tiberias Regions, Jordan Valley

The aim of the current research is to identify regional sources and trans-boundary flow leading to the observed salinity of Lake Tiberias (LT) -also known as the Sea of Galilee or Lake Kinneret-, and its surroundings, which is considered the only natural surface fresh water reservoir of the area. The current study will include all sources of brines in the Tiberias Basin (TB) with specific emphasis of the relationship between the brines from the Ha'on and Tiberias Regions (HTR).The tasks will be achieved by a multidisciplinary approach involving: (i) numerical modelling of density-driven flow processes (i.e., coupled heat and dissolution of evaporites), (ii) hydrochemical studies, supplemented by investigations of subsurface structures.(i) Numerical modelling will be carried out by applying the commercial software FEFLOW® (WASY, GmbH) complemented with the open source code OpenGeoSys developed at the UFZ of Leipzig (Wang et al., 2009). The final goal is to build a 3D regional-scale model of density-driven flow that will result in: (1) revealing the different interactions between fresh groundwater and natural salinity sources (2) elucidate the driving mechanisms of natural brines and brackish water body's movements.(ii) Hydrochemical study will include major, minor and, if possible, rare earth elements (REE) as well as isotope studies. The samples will be analysed at the FU Berlin and UFZ Halle laboratories. Geochemical data interpretation and inverse modelling will be supported by PHREEQC. Hydrochemical field investigations will be carried out in Tiberias basin and its enclosing heights, i.e. the Golan, Eastern Galilee and northern Ajloun in order to search for indications of the presence of deep, relic saline groundwater infested by the inferred Ha'on mother-brine. The current approaches will be supplemented by seismic and statistical data analysis as well as GIS software applications for the definition of the subsurface structures. The key research challenges are: building a 3D structural model of selected regions of TB, adapting both structural and hydrochemical data to the numerical requirements of the model; calibrating the 3D regional-scale model with observational data. The results of this work are expected to establish suitable water-management strategies for the exploitation of freshwater from the lake and from the adjacent aquifers while reducing salinization processes induced by both local and regional brines.

Landschaftsveränderungsdienst - Laverdi

Die Erkennung von Veränderungen der Landbedeckung der Erdoberfläche auf der Basis von satellitengestützten Fernerkundungsdaten ist seit Jahrzehnten ein sehr aktives Forschungsfeld. Das Ziel des Landschaftsveränderungsdiensts ist es, freie Copernicus-Satellitendaten für eine automatische Ableitung von Landbedeckungsänderungen zu nutzen und diese Informationen regelmäßig für einzelne Landschaftselemente (z.B. für Waldgebiete, Wasserflächen, Landwirtschaftsflächen usw.) über einen Web Service bereitzustellen. Copernicus Daten eignen sich aufgrund der hohen zeitlichen (ca. 3-5 Tage, je nach Sensor) und mittleren räumlichen Auflösung (ab 10m) ideal für eine regelmäßige bundesweite flächendeckende Analyse der Landbedeckung. Um eine hohe Bearbeitungsleistung zu erreichen wird die 'Copernicus Data and Exploitation Platform - Deutschland' (CODE-DE) für die Datenverarbeitung und -analyse genutzt. Es können aktuelle und konsistenteste Informationen über Landdeckungsänderungen abgeleitet werden, um kontinuierlich Geodaten in einer einheitlichen Qualität zu pflegen (siehe Abbildung 1). Andererseits können die gewonnenen Informationen genutzt werden, um statistisch relevante Geoinformationen zur quantitativen Beschreibung der UN-SDG-Indikatoren zu extrahieren. Die 2015 verabschiedete Agenda 2030 mit 17 Entwicklungszielen (SDG) und 169 Unterzielen verknüpft das Prinzip der Nachhaltigkeit mit der ökonomischen, ökologischen und sozialen Entwicklung. Die Umsetzung erfordert einen soliden Überprüfungsmechanismus. Dieser soll durch eine regemäßige nationale Erfassung von ca. 200 definierten UN-SDG-Indikatoren erfolgen, mit dem Ziel Fortschritte zu monitoren und die Politik zu informieren.

Schwerpunkt der deutschen Partner: Effektive Architekturen und Leistungswandler für Solarstromgeneratoren (PV/CPV) - ERG: Energy for a green society: from sustainable harvesting to smart distribution. Equipment, materials, design solutions and their applications

The research, development and demonstration activities planned for the ERG project focus on the solar energy supply chain, starting form solar cells and proceeding along with innovative energy extraction (harvesting) techniques, high efficiency power conversion and finally managing the energy distribution inside a smart grid, with the target of different classes of applications, from house to small area, as well as application specific 'local grid' (healthcare, automotive, etc). By considering the full solar energy supply chain, we expect to produce relevant improvements of the industrial state-of-the-art in the efficiency of solar cells, in the optimization of energy generated by photovoltaic systems, in the loss reduction of power converters and, finally, in energy management strategy. At the initial chain-link of the energy value chain, the project aims to design and develop a set of innovative solar cells. In particular we primarily target the development of ultra-thin (20 micron) Si wafer PV cells, Si hetero-junction cells (tandem/multi-junction and hetero-junction contacts), novel architectures (e.g., back-contact), novel materials (for Si hetero-junctions, ARC, and passivation dielectrics), novel approaches for screen printing and laser processing, with focus to the case of back-contact cells. As a promising low-cost alternative to Si, ERG will pursue the goal of totally printable dye-sensitized-solar-cells (DSSC). This will include (a) printable electrolyte (to replace liquid electrolyte), (b) advanced TiO2 electrode, and (c) counter electrode (to meet high performance DSSC applications). The overall objective is to demonstrate DSSC products for commercial applications. The next downward chain-link addressed by the project deals with optimization of the energy generated by photovoltaic systems by focusing on power management electronics for silicon cell panels and on micro electromechanical systems for Concentrated Photovoltaic cells (CPV). The complete supply chains will be considered for optimum energy exploitation by Maximum Power Point Tracking (MPPT) and power conversion on module / segment levels for PV and also CPV solar generators. The architecture study will elaborate different profiles of end-users, including direct grid connection, energy storage option and E-mobility support. As the final chain-link is concerned, the project will develop behavioural models for the individual components of the 'Smart Grid'. This allows the development of optimal energy dispatching and battery charging algorithms. These algorithms will obtain their input from sensors distributed over the network, with typically, but not exclusive, a wireless communication infrastructure. A full set of demonstrators, including innovative PV cells, novel conversion systems for PV and CPV inverters, and network demonstrators based on a household application and an industrial application will complete the project deliverables.

Fire, climate change and human impact in tropical ecosystems: paleoecological insights from the East African region

Fire is an important ecological factor of disturbance in African tropical ecosystems, driving vegetation dynamics and regulating nutrient cycling and biomass. The significance of wildfires for future environmental processes is underlined by recent projections of global warming, which predict more frequent and more intense extremes of natural events. Particularly in East Africa, where population growth and natural resource exploitation are among the highest in the world, strategies for sustainable economic development will have to deal with environmental changes at regional to continental scales. Understanding such complex responses to global change requires long-term records, since only they provide a way to observe the response of ecosystems to large-magnitude environmental change on decadal and longer time scales. We use high-resolution charcoal data from lake-sediment cores to reconstruct past fire/climate/human interactions in East Africa, aiming in particular 1) to understand how the fire regime influenced vegetation dynamics during the last millennia in savannah-type and sub-humid tropical ecosystems, 2) to test whether changes in fire regime are coupled with episodes of past climatic extremes inferred from the available sedimentological data, and 3) to detect early human deforestation and the timing of increased fire frequencies beyond its natural variability. Additionally, we will apply novel techniques such as molecular markers (benzene polycarboxylic acids, BPCAs) to complement the standard sedimentary approaches to reconstruct Holocene fire history. The proposed research addresses new, highly relevant questions for today's key issue of sustainability (economic development, natural resource management, adaptation of vulnerable communities to global change). Additionally, it will contribute with new high-quality data to ongoing multi-proxy research concerning the magnitude, frequency, and rates of past climate change in equatorial East Africa. Finally, the project will contribute to our understanding of tropical ecosystem functioning and its interaction with regional, cultural, and economic systems.

Production of activated clays for low-cost building materials in developing countries

Building Materials are a basic need, which is often difficult to meet in developing countries. Concrete is the building material best suited to meet these demands, although cement, the central ingredient is often disproportionately expensive in developing counties. The most promising option to lower costs (and environmental impact) is to blend conventional Portland cement with pozzolanic materials. The aim of this project is to develop technologies appropriate for the small scale, local production of pozzolans from clay (a material widely available) in conjunction with the exploitation of waste biomass for combined heat and power production. The modular concept of a clay activation unit, CAU to be coupled with a biomass boiler, will give the flexibility to adapt the solution to local conditions. We have already demonstrated that relatively common (low grade) clayey soils can be activated to give a pozzolan similar in performance to fly ash (from coal fired electricity production) widely used in the developed world. Results also indicate that it is possible to improve their reactivity by using and optimizing flash calcination, to allow high levels of substitution and very significant improvements in cost/performance ratio. To achieve this we need also to look at the performance of the activated clays in concrete from the point of view of rheology, hardening and durability to enable optimum cost/performance to be achieved according to local materials and applications. The partnership between LMC, EPFL and two academic groups in Cuba has already been established in a previous project. Furthermore, one of the Cuban partners plays a leading role in ECOSUR (a Swiss NGO) which has established workshops, producing low cost building materials, in many developing countries. In the first part of the project significant scientific advances were made, which enabled a huge acceleration in progress, relative to previous work by the Cuban partners alone. In addition, 3 Cuban PhD students spent several months working in the Swiss laboratory and have now returned to Cuba to continue their research. In this project, funding is requested for one PhD student to be based in Switzerland, who will work closely with 3 Cuban PhD Student (funded be the Cuban government). On the Cuban side, funds are requested for essential equipment and to fund the stays of the students at EPFL. Each of the Cuban students will spend 4-8 months working at EPFL during the course of the project.

Matter and nutrient fluxes - Scenario development and compilation of an interdisciplinary (Internet) atlas

For centuries sophisticated oasis agriculture and ocean fishery provided the living of the sedentary population in the mountainous desert country of Oman. Since the early 1970s, the country's political opening and commercial oil exploitation led to fundamental changes in the conditions for agricultural production. Being part of an interdisciplinary programme comprising research in social and natural sciences, the overall aim of this subproject is to quantify the bio-physical processes and socio-economic variables that determine the current crop-livestock husbandry in Omani mountain oasis settlements. To this end, nutrient and water use efficiencies in the cropping system are determined along with feeding strategies in livestock husbandry, labour needs and financial in- and outputs related to the various activities. Through bio-economic modelling land use options that are biologically and economically sustainable are identified and scenarios are developed for a socially acceptable future agricultural use of the millennia-old terrace systems with their high cultural value.

FP6-SUSTDEV, Health and Environment Network (HENVINET)

To protect the health of populations and individuals, policies need to integrate environmental and health issues. The aim of HENVINET is to support such informed policy making. HENVINET will review, exploit and disseminate knowledge on environmental health issues based on research and practices, for wider use by relevant stakeholders. Further, it will lead to validation of tools and results with emphasis on the four priority health endpoints of the EHAP 2004-2010, and will provide structured information overview that may be utilized by other actors relevant to Environment and Health Strategy. Building on activities such as AirNET, CLEAR, PINCHE, INTARESE and SCALE, HENVINET will collect, structure and evaluate new material and present it in a consistent manner, which will lend itself to transparency and identification of knowledge gaps. HENVINET will establish an overview of results, activities, projects and tools existing in Europe and will promote stakeholder networking through workshops and conferences. Knowledge, best practices and decision support tools will be reviewed to allow wider exploitation by the relevant stakeholders such as policy makers. Recognizing that dissemination of knowledge, best practices and decision support tools is crucial in supporting the implementation of the European EHAP, the project will define ways to disseminate information in collaboration with main stakeholders, with emphasis on the needs of users of information, more than of those producing it. To allow for efficient data gathering, information exchanges, and targeted dissemination, the project will utilize state-of-the-art internet solutions and methodologies. To further promote interactions with stakeholders and relevant international organisations, an external Reference group will be set up.

Miscanthus 'Giganteus' als Industrierohstoff und für die thermische Nutzung

Die Bereitstellung von Industrierohstoffen und Energie in der Form von Wärme und elektrischen Strom aus Einjahres-, zweijährigen und ausdauernden Pflanzen stellt in allen industrialisierten Ländern und auch in Österreich mittel- und langfristig eine bedeutende Alternative zum Verbrauch fossiler Resourcen dar. Miscanthus Giganteus, eine ausdauernde Pflanze, benötigt eine stark vom Standort abhängige ein- bis zweijährige Etablierungsphase. Die Ernte des Aufwuchses ist erst ab dem zweiten Vegetationsjahr wirtschaftlich. Nach bisherigen Ergebnissen und Erwartungen ist eine ca. 20jährige Nutzungsdauer möglich. Die Feldversuche an fünf bezüglich Klima und Bodenform (Bodentyp und Art) unterschiedlichen Standorten ergaben von 1989 bis 2001 jährlich Trockensubstanzerträge von 17500 bis 24000 kg/ha. Die Ertragsschwankungen zwischen den Jahren sind relativ niedrig, standortbezogen zwischen 2000 und 4000 kg/ha. Zwischen den einzelnen Standorten gibt es bedeutende Ertragsunterschiede. Jährlich hohe Erträge werden an den Standorten ILZ (Steiermark) und in ST. FLORIAN (Oberösterreich) bei durchschnittlichen Jahresniederschlagsmengen zwischen 700 und 900 mm erzielt. Durch die geringeren Niederschläge bedingt ist das Ertragsniveau in MICHELNDORF, MARKGRAFNEUSIEDL, GROSS ENZERSDORF und STEINBRUNN niedriger. Bei Bewässerung in einer Menge von 100 bis 150 mm (Juli bis September) steigt der Biomasseertrag um ca. 2000 bis 5000 kg/ha an. Das Ertragsmaximum wird Ende November - Anfang Dezember erreicht. Bis zum üblichen Erntetermin Ende Februar - Mitte März fällt der Ertrag aufgrund des Blattfalles und Abbrechen der dünnen Stängel und Triebspitzen ab. Der Wassergehalt im Erntegut liegt bei einer Ernte Ende November - Anfang Dezember über 50 Prozent, er fällt je nach mittlerem Stängeldurchmesser und Winter-Witterungsverlauf bis Ende Februar auf 30 bis ca. 42 Prozent ab. Eine Stickstoffdüngermenge über 60 kg N/ha führt nur selten zu steigenden Erträgen. Gülle als Dünger erreicht wegen der meist dichten Blattmulchauflage nur eine geringe Düngerwirkung. Die wesentlichen Qualitätskriterien bei einer thermisch energetischen bzw. stofflichen Nutzung sind konstant. Der Aschegehalt im Erntegut weist ab dem dritten Aufwuchsjahr Werte zwischen 3,2 und 5,0 Prozent auf. Auch der N- Gehalt im Erntegut bleibt ab dem Dritten Aufwuchsjahr beinahe konstant und liegt zwischen 0,3 und 0,42 Prozent. Den größten Anteil der Miscanthusasche bilden Siliciumoxyd (ca. 40 bis 50 5) und K2O (12 bis 20 Prozent). Miscanthuserntegut ist bei entsprechender Technologie ein Rohstoff für die Zellulosegewinnung. Der Gehalt ab dem dritten Aufwuchsjahr liegt bei ca. 47,5 Prozent und ist nur geringfügig niedriger als im Laub- oder Nadelholz.

Schwerpunktprogramm (SPP) 1294: Bereich Infrastruktur - Atmospheric and Earth system research with the 'High Altitude and Long Range Research Aircraft' (HALO), Methods and algorithms for data exploitation of the imaging Fourier transform spectrometer GLORIA-AB on HALO - MaxiFTS -

GLORIA combines a Michelson interferometer with a detector array of 128 x 128 pixels and will be the first 2D infrared limb imaging spectrometer worldwide. It is designed for HALO and will measure the distribution of temperature and a considerable number of trace constituents along with cloud mapping with unprecedented spatial resolution in the free troposphere and lower stratosphere. It is an essential contribution to the HALO demo missions TACTS, POLSTRACC, and CIRRUS-RS. Imaging Fourier transform spectrometers impose a number of challenges with respect to instrument calibration / characterisation and for algorithm development. The work of the first proposal focused on characterisation and modeling of the instrument and on the development of methods and algorithms which are capable of generating calibrated spectra with high accuracy. Accurately calibrated spectra are a prerequisite for the retrieval of atmospheric parameters and the scientific data exploitation. Within this renewal proposal the developed characterisation methods will be applied to the instrument in flight configuration, and the new algorithms will be used to generate highly accurate calibrated spectra from the raw interferograms measured during the HALO demo missions. The work will be completed by a thorough error analysis for the calibrated spectra. Finally, instrument settings, calibration scenario and data processing shall be optimised with respect to data quality. This proposal contributes to the development of high technology sensors and instruments for the use on HALO.

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