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Biogeochemical Processes in Tropical Soils

In recent years science has taken an increased interest in mineralization processes in tropical soils in particular under minimal tillage operations. Plant litter quality and management strongly affect mineralization-nitrification processes in soil and hence the fate of nitrogen in ecosystems and the environment. Plant secondary metabolites like lignin and polyphenols are poorly degradable and interact with proteins (protein binding capacity) and hence protect them from microbial attack. Nitrification, a microbiological process, directly and indirectly influences the efficiency of recovery of N in the vegetation as well as the loss of N (through denitrification and leaching) causing environmental pollution to water bodies and contributes to global warming (e.g. the greenhouse gas N2O is emitted as a by-product of nitrification and denitrification). Nitrifiers comprise a relatively narrow species diversity (at least as known to date) and are generally thought to be sensitive to low soil pH and stress. Despite these properties nitrification occurs in acid tropical soils with high levels of aluminium and manganese. Thus the main objective of the project will be the identification of micro-organisms and mechanisms responsible for mineralization-nitrification processes in acid tropical soils and the influence of long-term litter input of different chemical qualities and minimal tillage options. The project will include the use of stable isotopes (15N, 13C), mass spectrometry, gas chromatography (CO2, N2O), biochemical methods (PLFA) and molecular biology (16s rRNA., PCR, DGGE)

Regulation der photosynthetischen Effizienz der Biomassebildung im dynamischen Lichtklima bei exemplarischen Grünalgen und Diatomeen

In dem Vorhaben wird untersucht, wie wirksam die absorbierte Lichtenergie in Biomasse konvertiert wird. Vergleichend werden Grünalgen und Diatomeen unter verschiedenen Licht- und Nährstoffbedingungen studiert. Auf diese Weise können die metabolischen Kosten unter Nährstoffmangel oder anderen produktivitätsbegrenzenden Bedingungen studiert werden. So wird auch die Säureanpassung ausgewählter Phytoplankter untersucht, um die Biomassebildung in extrem sauren Tagebaurestseen auf physiologischer Ebene zu verstehen. Es konnte gezeigt werden, dass unter Stickstoffmangel die Überführung anorganischen Kohlenstoffs in Biomassebildung durch eine Veränderung der makromolekularen Zusammensetzung der Zellen ähnlicher Effizienz stattfindet, wie unter optimaler Stickstoffversorgung. Dies führt zu einer ökologisch bedeutsamen Teilentkopplung des C und N Kreislaufs im Ökosystem. Ähnliches beobachtet man auch bei der Anpassung von Phytoplanktonalgen an extrem saure Bedingungen wie man sie in sauren Tagebaurestseen vorfindet.

Gemengeanbau von Ackerbohnen und Ölfrüchten

Der Anbau von Ölpflanzen zur Gewinnung von Speiseöl und Energie ist bislang im Organischen Landbau wenig entwickelt. Zum einen mindern Probleme bei der Regulierung von Schaderregern und Unkraut die Wirtschaftlichkeit, zum anderen konkurriert der Anbau von Energiepflanzen um Fläche für die Erzeugung von Lebensmitteln. Der Gemengeanbau leistet einen Beitrag zur Diversifizierung im Ackerbau und lässt Synergie-Effekte zwischen den Gemengepartnern wirksam werden. Eine effizientere Ressourcennutzung, geringere Anfälligkeit gegenüber Schaderregern und reduziertes Unkrautaufkommen können zu höheren Gesamterträgen bzw. Gewinnen je Flächeneinheit führen. Im Hinblick auf diese Aspekte wird untersucht, inwieweit die Ölsaaten Öllein (Linum usitatissimum L.), Saflor (Carthamus tinctorius L.) bzw. Senf (Sinapis alba L.) für den jeweils zeitgleichen Anbau mit Ackerbohnen (Vicia faba L.) geeignet sind. In Abhängigkeit von verschiedenen Standraumzumessungen werden die Erträge und die Konkurrenzverhältnisse um Stickstoff und Wasser bei den jeweiligen Gemengepartnern untersucht,sowie die Ölsaaten hinsichtlich Ölgehalt und Fettsäurezusammensetzung analysiert. Arbeitshypothesen: - Der zeitgleiche Anbau von Ackerbohnen und Ölfrüchten führt zu höheren Gesamterträgen bei nur unwesentlich verminderten Ackerbohnen-Erträgen. - Die hauptsächlich im Bodenraum zwischen den Ackerbohnenreihen freigesetzten Stickstoffmengen werden zur Ertragsbildung der Ölfrüchte effizient genutzt. - Ein weiterer Abstand zwischen Ölfrucht- und Ackerbohnenreihe führt zu geringerer interspezifischer Konkurrenz und durch gleichmäßigere Durchwurzelung des Bodenraumes zur effizienteren Nutzung von bodenbürtig freigesetztem Stickstoff und Wasser. Die Folge sind, verglichen mit engerem Reihenabstand, höhere Ölfruchterträge und nur unwesentlich geringere Ackerbohnen-Kornerträge. - Die Ölfrüchte Saflor, Öllein und Senf nehmen aufgrund ihres Pfahlwurzelsystems Stickstoff auch aus tieferen Bodenschichten auf und senken so das Austragungspotential von bodenbürtig freigesetztem Stickstoff bzw. Stickstoff-Restmengen.

Nationale und internationale Hochwasserschutzpolitik am Rhein. Eine Mehrebenen-Politikfeldanalyse

Die Hochwasserereignisse im Dezember 1993 und Januar 1995 am Rhein, Juli/August 1997 an der Oder sowie im August 2002 an der Elbe und die hervorgerufenen Schäden haben in Deutschland zu der Erkenntnis geführt, dass baulich-technische Hochwasserschutzmaßnahmen nicht ausreichen, sondern dass ein vorsorgeorientiertes, die Ziele einer dauerhaft umweltgerechten Entwicklung verfolgendes Hochwassermanagement erforderlich ist. Dazu zählen der technische Hochwasserschutz, die weitergehende Hochwasservorsorge und die Flächenvorsorge zum natürlichen Rückhalt als vorbeugender Hochwasserschutz. Allerdings treten Defizite bei der Operationalisierung dieser politischen Ziele und Strategien auf der Umsetzungsebene auf. Es bleibt bisher die Frage unbeantwortet, ob es sich dabei um Regelungs- oder Vollzugsdefizite handelt. Das Forschungsvorhaben am Institut für Forst- und Umweltpolitik verfolgt das Ziel, die Bedingungen für die Implementation von existierenden politischen Initiativen zum vorbeugenden Hochwasserschutz zu untersuchen. Bedeutsam für die Untersuchung ist dabei die Betrachtung von Akteuren der verschiedenen politischen Ebenen und Sektoren im Durchführungsprozess, deren Kommunikations- und Machtstrukturen sowie der eingesetzten Instrumente, um hieraus Erkenntnisse über die politische Steuerung und deren Wirkung gewinnen zu können. Die Politikfeldanalyse sieht den Vergleich der Hochwasserschutzpolitik der Bundesländer Nordrhein-Westfalen, Rheinland-Pfalz und Baden-Württemberg vor und wird unter Verwendung von Methoden der qualitativen Sozialforschung durchgeführt. Im Ergebnis sollen Effizienzfaktoren ermittelt und schließlich Handlungsempfehlungen für die Implementation von ressort- und grenzübergreifenden Planungsprozessen in komplexen politischen Systemen abgeleitet werden.

ERA-NET - Development of test methods for non wood small-scale combustion plants

Non wood fuels for small-scale furnaces have attracted increasing interest in several European countries. New technological approaches are on the way, but the verification of any such developments is difficult and there is a large uncertainty about testing procedures and equipment. While for wood combustion standardized European measuring regulations are available and broadly applied, the testing of cereal fuel combustion is generally not following a commonly accepted procedure. Consequently the results of such measurements are not fully comparable. This applies particularly for the international level, which is here of particular relevance due to the fact that a combustion technology development for a niche application can only be economically viable if a sufficiently large marketing area can be taken into focus. The overall objective of the proposal is therefore to contribute through research to the development of uniform and comparable European procedures for testing of small-scale boilers up to a power out of 300 kW for solid biomass from agriculture like straw pellets and energy grain. The driving forces and barriers will be worked out; existing legal regulation for the installation (approval by the local authorities) in the participating countries will be collected. The state of the art of the non wood biomass boiler technology will be identified; the need for standardized tests for type approval tests and the measures to establish a European Standard will be shown. Measurement methods with special emphasis on efficiency and emissions will be worked out and the requirements and specifications of test fuels will be proposed. Test runs will be carried out following preliminary test procedures based on existing European standards for wood boilers. Based on the results of these test runs a draft for a Europe-wide uniform test procedure will be proposed. Preparatory work for a European standardization process including a round robin test will be done.

Native plants and mycorrhizal fungi in wind erosion control in the Kailash-Manasarovar region (Tibet, China)

We study the effects of plants and root-associated fungi on wind erosion within the alpine environment of Tibet. China is one of the countries most affected by desertification processes and Tibet, in particular, a key region in desertification combat. The presented project focuses on the Barkha Plain surrounded by Mount Kailash and the Lake of Manasarovar (Ngari Prefecture). This Western Tibet region experienced little scientific attention but, nowadays, faces rapidly increasing touristic activities and expanding local settlements associated with socio-economic changes that are serious threats to the delicate ecological balance and potential triggers of desertification. It exists almost unanimous agreement that revegetation is the most efficient and promising strategy to combat wind erosion and desertification in the long term. However, re-colonising success is often poor, mainly under extreme environmental conditions. Compared to conventional practices, the approach of the presented project attains better accordance with natural succession processes and promises acceleration of both plant and soil development and, conclusively, more efficient desertification control. The project assesses the potential of native plants and symbiotic fungi to control wind erosion and desertification processes. It aims to identify key plants and fungi that increase soil aggregate stability and efficiently drive succession into a natural and self-maintaining cycle of the ecosystem. Furthermore, it provides crucial information for implementing environmentally compatible and cost-effective measures to protect high-elevation ecosystems against desertification. Within three successional stages (early, intermediate, late), field investigations are performed on the basis of Modified-Whittaker plots. Classic methods of vegetation analysis and myco-sociology are combined with analysis of distribution patterns at different scales (patchiness, connectivity). Comprehensive soil analysis is performed comprising grain size distribution, aggregate stability, pH as well as water and nutrient contents. Additionally, important parameters of wind erosion are measured concurrently and continuously to assess their magnitude and variability with respect to vegetation and soil at different levels of development. The parameters addressed, include sediment transport, air temperature, radiation, precipitation, relative humidity as well as speed and direction of wind. Surface moisture is recorded periodically and roughness described. Species and environmental parameters are checked for spatial correlation. Cutting edge technologies are applied in laboratory work, comprising molecular methods for fungal species identification and micro-tomography to analyse soil structure. Furthermore, successfully cultivated fungi and plants are subject of synthesis experiments and industrial propagation in view of practical implementation in restoration measures.

Improving soil erosion assessment in Swiss Mountainous areas using radionuclides (137Cs, 239-240Pu)

To efficiently mitigate and control soil losses by erosion and reduce their environmental impacts in Alpine grasslands, reliable and validated methods for comprehensive data generation on the magnitude and spatial extent of soil erosion are needed. Classical approaches to quantify erosion rates include artificial radionuclides such as 137Cs and 239-240Pu which originated from thermonuclear weapon tests in the 1950s-1960s and nuclear power plant accidents (i.e. Chernobyl). Because these radionuclides are rapidly and strongly adsorbed to fine soil particles, they accumulate in the top soil with limited migration and bioavailability. Documenting the subsequent redistribution of the radionuclides, which move across the landscape in association with soil/sediment particles primarily through physical processes, requires effective means of tracing rates and patterns of erosion and deposition within landscapes. To this end, the general aim of this project is to develop a radio-isotopic valid approach to assess and quantify sheet erosion in Alpine grasslands.

FP6-POLICIES, Sustainable batteries (SUBAT)

By the end of 2004 the Commission is required to provide report on the possibility to maintain, or not, cadmium, in the exemption list of Directive 2000/53 on End-of-Life Vehicles. The SUBAT proposal aims to make a comprehensive and complete assessment of commercially available and forthcoming battery technologies in the world, including Ni-Cd, on the basis of: - a technical assessment comparing their performances for full EV and HEV (specific energy and power, proven cycle life and calendar life, life cycle cost analysis, operation at extreme temperature, charge acceptance, maintenance, safety, energetically efficiency of the battery systems, availability of recycling process at industrial stage, operation during applications); SUBAT will also take into account the status of these batteries as to their availability as commercial products; - an environmental assessment in order to be able to give them an environmental score which can designate them as being a sustainable solution or not; A life-cycle-analysis approach will investigate availability of primary materials, environmental impact of extraction and manufacturing of the battery, emissions from the battery during use, release of components in case of accident, recycling of active materials, production of non-recyclable waste and environmental impact of recycling processes; - an economical assessment with both a micro-economical analysis of production, manufacturing cost of the batteries, forecast cost for the consumers and a macro-economical study to take into account the position of battery manufacturers on the global market, assessing European vs. non-European products and influence on the European trade balance. Through this multidisciplinary approach, SUBAT will allow to define an overall view of all aspects of the automotive battery market, in order to provide the Commission with a valuable policy support tool that will assist in tracing the pathways for the future sustainable transport.

Calcium cycle for efficient and low cost CO2 capture in fluidized bed systems (C3-CAPTURE)

Objectives: The project aims on developing a dry CO2 capture system for atmospheric and pressurized fluidized bed boilers. The atmospheric option will be developed towards a pilot plant application. For the pressurized option the project seeks for a proof of principle to determine if the advantages of a pressurized capture system can balance the problems known from existing PFBC systems. The quantifiable objectives are: - Low CO2 capture costs (less than 20 Euro/t for atmospheric, less than 12 Euro/t for pressurized sy stems) - Acceptable efficiency penalty for CO2 capture (less than about equal to 6 percent nel). - greater than 90 percent carbon capture for new power plants and greater than 60 percent for retrofitted existing plants - A purge gas stream containing greater than 95 percent CO2 - A solid purge usable for cement production - Sim ultaneous sulphur and CO2 removal with sulphur recovery option Approach: Limestone is a CO2 carrier. The CO2 can be released easily in a conventional calcination process, well known in the cement and lime industry. By integrating a closed carbonation/calc ination loop in the flue gas of a conventional CFB-boiler, the CO2 in the flue gas can be removed. The heat required for calcination is released during carbonation and can be utilised efficiently (high temperature) in the steam cycle of the boiler. Concent rated CO2 can be generated when using oxygen blown calcination. Because the fuel required for supplying heat for calcination is only a fraction of the total fuel requirements, the required oxygen is only about 1/3 of the oxygen required for oxyfuel process es. The work programme: 1.Definition of the technical and economic boundary conditions 2.Selection and improvement of sorbent materials 3.Lab scale and semi-technical scale process development (experimental work) 4.Technical and economic evaluation 5.Des ign of a 1 MWth Pilot plant.

FP6-SUSTDEV, Groundwater Artificial recharge Based on Alternative sources of wateR: aDvanced INtegrated technologies and managEment 8GABARDINE)

Aquifers are the main source of water in most semi-arid areas of the Mediterranean basin. As a result of over-exploitation hydrologic deficits of varying acuity prevail in these areas. Seawater intrusion and pollution have been identified as the primary factors for quality degradation. Further deterioration can be expected based on trends in the precipitation regime attributed to climate change. The objective of this project is to identify alternative sources of water and to investigate the feasibility, both environmental and economic of their utilization. Alternative water sources to be artificially recharged comprise: surface water runoff, treated effluent, and imported water. Furthermore, brackish water bodies, present in many aquifers could be utilised after desalination. The project structured into eight work-packages comprehensively addresses all issues related to the problem: expected precipitation rates, recharge and water budgets, identification of potential alternative water sources and technologies for their utilization, development of tools for the management of groundwater resources under artificial recharge conditions, aquifer vulnerability assessment, characterization of the unsaturated zone, and mixing effects. Four test sites have been selected for practical application of the approach. Substantial field testing, integration of technologies and findings to ensure optimal implementations of aquifer recharge alternatives, quantification of socio-economic impacts and development of dissemination platform are planned. Finally a carefully designed project management shall drive and accompany the project execution in order to ascertain consistency and efficiency.

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