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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.

Diffusion and advection with sorption of anions, cations and non-polar molecules in organo-clays at varying thermo-chemical conditions - validation by analytical methods and molecular simulation

The sorption of anions in geotechnical multibarrier systems of planned high level waste repositories (HLWR) and of non-ionic and organic pollutants in conventional waste disposals are in the center of recent research. In aquatic systems, persistent radionuclides such as 79Se, 99Tc, 129I exist in a form of anions. There is strongly increasing need to find materials with high sorption capacities for such pollutants. Specific requirements on barrier materials are long-term stability of adsorbent under various conditions such as T > 100 C, varying hydrostatic pressure, and the presence of competing ions. Organo-clays are capable to sorb high amounts of cations, anions and non-polar molecules simultaneously having selectivity for certain ions. This project is proposed to improve the understanding of sorption and desorption processes in organo-clays. Additionally, the modification of material properties under varying chemical and thermal conditions will be determined by performing diffusion and advection experiments. Changes by sorption and diffusion will be analyzed by determining surface charge and contact angles. Molecular simulations on models of organo-clays will be conducted in an accord with experiments with aim to understand and analyze experimental results. The computational part of the project will profit from the collaboration of German partner with the group in Vienna, which has a long standing experience in a modeling of clay minerals.

Schwerpunktprogramm (SPP) 1488: Planetary Magnetism (PlanetMag), Probing the Earth's subdecadal core-mantle dynamics based on satellite geomagnetic field models

The CHAMP mission provided a great amount of geomagnetic data all over the globe from 2000 to 2010. Its dense data coverage has allowed us to build GRIMM - GFZ Reference Internal Magnetic Model - which has the highest ever resolution for the core field in both space and time. We have already modeled the fluid flow in the Earth's outer core by applying the diffusionless magnetic induction equation to the latest version of GRIMM, to find that the flow evolves on subdecadal timescales, with a remarkable correlation to the observed fluctuation of Earth rotation. These flow models corroborated the presence of six-year torsional oscillations in the outer core fluid. Torsional oscillation (TO) is a type of hydromagnetic wave, theoretically considered to form the most important element of decadal or subdecadal core dynamics. It consists of relative azimuthal rotations of rigid fluid annuli coaxial with the mantle's rotation and dynamically coupled with the mantle and inner core. In preceding works, the TOs have been studied by numerical simulations, either with full numerical dynamos, or solving eigenvalue problems ideally representing the TO system. While these studies drew insights about dynamical aspects of the modeled TOs, they did not directly take into account the observations of geomagnetic field and Earth rotation. Particularly, there have been no observation-based studies for the TO using satellite magnetic data or models. In the proposed project, we aim at revealing the subdecadal dynamics and energetics of the Earth's core-mantle system on the basis of satellite magnetic observations. To that end, we will carry out four work packages (1) to (4), for all of which we use GRIMM. (1) We perform timeseries analyses of core field and flow models, to carefully extract the signals from TOs at different latitudes. (2) We refine the conventional flow modeling scheme by parameterizing the magnetic diffusion at the core surface. Here, the diffusion term is reinstated in the magnetic induction equation, which is dynamically constrained by relating it to the Lorentz term in the Navier-stokes equation. (3) We develop a method to compute the electromagnetic core-mantle coupling torque on the core fluid annuli, whereby the energy dissipation due to the Joule heating is evaluated for each annulus. This analysis would provide insights on whether the Earth's TOs are free or forced oscillations. (4) Bringing together physical implications and computational tools obtained by (1) to (3), we finally construct a dynamical model for the Earth's TOs and core-mantle coupling such that they are consistent with GRIMM and Earth rotation observation. This modeling is unique in that the force balances concerning the TOs are investigated in time domain, as well as that the modeling also aims at improving the observation-based core flow model by considering the core dynamics.

Soil colour spectra of prehistoric pit fillings as a new analytical tool to measure changing soil characteristics over time on a regional scale

Prehistoric pits are filled with ancient topsoil material, which has been preserved there over millennia. A characteristic of these pit fillings is that their colour is different depending on the time the soil material was relocated. Soil colour is the result of soil forming processes and soil properties, and it could therefore indicate the soil characteristics present during that specific period. To the best of our knowledge, no investigation analysed and explained the reasons for these soil colour changes over time. The proposed project will investigate soil parameters from pit fillings of different archaeological periods in the loess area of the Lower Rhine Basin (NW-Germany). It aims to implement the measurement of colour spectra as a novel analytical tool for the rapid analyses of a high number of soil samples: the main goal is to relate highresolution colour data measured by a spectrophotometer to soil parameters that were analysed by conventional pedogenic methods and by mid infrared spectroscopy (MIRS), with a main focus on charred organic matter (BPCAs). This tool would enable us to quantify the variation of soil properties over a timescale of several millennia, during different prehistoric periods at regional scale and for loess soils in general. Detailed information concerning changing soil properties on a regional scale is necessary to determine past soil quality and it helps to increase our understanding of prehistoric soil cultivation practices. Furthermore, these information could also help to increase our understanding about agricultural systems in different archaeological periods.

Evaluating current European agri-environment schemes to quantify and improve nature conservation efforts in agricultural landscapes (EASY)

Research question: Agri-environment schemes play an increasingly important role in European CAP (Common Agricultural Policy) to support biodiversity and environment in agricultural landscapes. They have been implemented since 1992 and now cost a yearly 1.7 billion Euro. Still, there is no conclusive evidence that these schemes actually do contribute to the conservation of particularly biodiversity. The primary objective of this project is to evaluate the (cost-) effectiveness of European agri-environment schemes in protecting biodiversity and to determine the primary processes that determine their effectiveness. This project furthermore aims to determine how CAP may be introduced in candidate EU-members without unacceptable loss of biodiversity. It will provide simple guidelines how researchers, governmental authorities may efficiently evaluate agri-environmental measures. Aim: Agri-environment schemes have been used to protect biodiversity and environment in agricultural areas since 1992. Their effectiveness has never been reliably evaluated. This project aims to evaluate the (cost-)effectiveness of agri-environment schemes with respect to biodiversity conservation in five European countries. It will determine the proper scales that have to be addressed for conservation efforts for a range of species groups. It will determine the most important environmental factors that influence the effectiveness of the schemes. Based on this, recommendations will be made how the effectiveness of schemes may be improved and simple guidelines will be produced how ecological effects of agri-environment schemes can be evaluated efficiently by governmental authorities or other institutions. The ecological effects of the introduction of CAP in a candidate EU-member will be investigated to reduce negative side effects of anticipated land-use changes Scientific methods: We will examine the effectiveness of agri-environment schemes by surveying pairs of fields: a field with an agri-environment scheme and a nearby field that is conventionally managed. In five countries, in each country in three areas, and in each area on seven pairs of fields the species richness of birds, plants and three insect groups (pollinators, herbivores, predators) will be determined. Effects of schemes on pollination efficiency and pest control will be examined using indicator communities. Correlative studies will examine the effects of landscape structure, land-use intensity and species pool on the effectiveness of agri-environmental measures. The spatial scale that is relevant to nature conservation efforts will be investigated via the spatial distribution of species groups. The results will be used to formulate recommendations how to improve the effectiveness of agri-environment schemes and to construct a set of simple guidelines how schemes can be evaluated efficiently yet reliably.

Entwicklung eines Analyseverfahrens für Tenside aus Wasch- und Reinigungsmitteln und dessen praktische Anwendung auf Abwasserproben von Kläranlagenabläufen

Zur Bestimmung der Konzentrationen linearer Alkylbenzolsulfonate (LAS) und Alkylethersulfate (AES) in Kläranlagenabläufen wurden 7-Tagesmischproben (n=33) an Abläufe von 33 konventionellen Kläranlagen in Deutschland genommen. Zudem wurden an vier der untersuchten Kläranlagen die Zuläufe beprobt und ebenfalls auf LAS und AES untersucht, um Rückschlüsse auf die Entfernung dieser Tenside in konventionellen Kläranlagen ziehen zu können. Insgesamt umfasste die Studie die Analyse von vier LAS-Homologen (C10-C13) sowie von jeweils 10 Ethoxymeren zweier Homologe von AES (C12 und C14, jeweils mit 0-9 Ethoxygruppen). Die Probenvorbereitung bestand aus der Entfernung der wässrigen Phase mit Hilfe eines Rotations-Vakuum-Konzentrators und anschließender Resolvatisierung des Trockenrückstandes in einer definierten Menge Reinstwasser und Acetonitril. Die Identifikation und Quantifizierung der Zielanalyten erfolgte mittels Hochleistungsflüssigkeitschromatographie mit Tandem-Massenspektrometrie-Kopplung (HPLC-MS/MS). Die Leistungsfähigkeit der analytischen Methoden wurde in Leitungswasser und Kläranlagenablauf evaluiert. Die Analysemethoden zeigten für beide Matrices eine allgemein gute Richtigkeit sowie Präzision. Basierend auf den geschätzten mittleren Konzentrationen einzelner LAS-Homologe wurde eine mittlere Gesamtkonzentration von 14,4 Mikro g/L in Kläranlagenabläufen ermittelt. Verglichen mit LAS, wurden für AES stets geringere Gesamtkonzentrationen im Ablauf gemessen: Die mittlere AES-Gesamtkonzentration in den Abläufen betrug 0,57 Mikro g/L. Zwischen den Gesamtkonzentrationen von AES und LAS bestand keine Korrelation. In den Zuläufen beprobter Kläranlagen wurden im Mittel 3.200 Mikro g/L LAS detektiert. Damit betrug die mittlere Entfernung für LAS 99,6 %. Die mittlere AES-Konzentration im Kläranlagenzulauf belief sich auf 680 Mikro g/L, was einer mittleren AES-Entfernung von größer als 99.9% entspricht. Retrospektives Screening von 1.564 Tensiden und deren Transformationsprodukte (TPs) erfolgte durch ein zweites Labor unter Anwendung der Ultrahochleistungsflüssigkeitschromatographie mit Flugzeitmassenspektrometer-Kopplung (UHPLC-QTOF-MS). In vielen Fällen wurde die Konzentration von LAS von der Summe der Konzentrationen der Neben- und Transformationsprodukte von LAS überstiegen. Für die LAS-Nebenprodukte Dialkyltetralinsulfonate (DATS) lag die maximale Summenkonzentration bei 19 Mikro g/L, für die Sulfophenylalkylcarbonsäuren (SPACs) bei 17 Mikro g/L und für die Sulfotetralinalkylcarbonsäuren (STACs) bei 5,3 Mikro g/L. Hohe Konzentrationen von bis zu 7,4 Ìg/L wurden für Polyethylenoglycole in den Abwasserproben bestimmt. Die Gesamtkonzentration aller quantifizierten Tenside, TPs und Nebenprodukte in einer einzelnen Probe betrug bis zu 82 Mikro g/L.

Predicting the complex coupling of chemistry and hydrodynamics in fluidised bed methanation reactors for SNG-production from wood (bioSNG - fundamentals of methanation)

Synthetic natural gas from wood-How can the synthesis be optimised? The production of bio natural gas as a fuel and combustible made of biomass that is rich in lignin presents an interesting alternative to the use (combustion) of biomass purely as a source of energy. In this project, researchers examine how the chemical reactions, the mass transfer and the fluid dynamics in fluidised bed reactors mutually influence each other. In experiments, they check whether the reactor simulation mirrors the actual processes precisely enough. This is important for optimising processes for the production of bio natural gas with the help of simulations. Background Woody biomass containing lignin, such as wood and straw, can so far only be transformed into a combustible product gas via thermochemical processes such as gasification. From the wood gas thereby gained, a synthetic natural gas is made via fluid bed methanation. This so-called bio-SNG (synthetic natural gas) can be fed directly into the existing natural gas network and is available as a renewable and CO2-neutral substitute for conventional fossil natural gas and as fuel for natural gas vehicles. The fluid bed methanation, during which wood gas is transformed into methane, works well at the pilot scale, but further research is necessary before it can be implemented in larger production plants. Aim The goal of the experiments is to collect on a 160 kW pilot plant data of sufficiently good quality that will enable researchers to validate the computer models. These models are used to upscale the fluid bed methanation to the scale of commercial plants and to optimise processes. During the experiments, the researchers will vary temperature, pressure, gas flows and gas composition. For process optimisation, the researchers will measure the fluid dynamics, the axial temperature and the gas phase concentration profiles and will use a catalyst sampling system. Significance The computer modules validated via the measurements on the pilot plant enable researchers to derive meaningful model experiments in the perspective of the 'observing passenger'. In these experiments, a small amount of a catalyst is exposed to a periodically changing gas mixture, which is what happens to the catalyst when there is movement in the fluidised bed reactor. This innovative approach can be applied to all chemical reactors with moving solids.

European Research Infrastrictures for Nuclear Data Application

Different concepts involving critical (fast) reactors or subcritical accelerator-driven systems are being studied in view of their transmutation capabilities. These design studies imply high demands on the underlying nuclear database. The need for improved nuclear data has been expressed in the Strategic Research Agenda of the SNE-TP ( Sustainable Nuclear Energy Technology Platform). The accurate knowledge of neutron and proton induced nuclear reactions in the fast, intermediate- and high energy domains (En=1keV to 500 MeV) is of crucial importance for predicting the capabilities of reducing the inventory of plutonium, minor actinides, and long-lived fission products. In the past, this energy domain was not investigated with high priority because of minor importance for conventional light-water reactors. An additional challenge is the tightening demand on the accuracy of the data, especially for assessing criticality safety aspects and designing fuels for very high burn-up. The ERINDA project aims for a coordination of European efforts to exploit up-to-date neutron beam technology for novel research on advanced concepts for nuclear fission reactors and the transmutation of radioactive waste. Such waste is already existing in appreciable quantity due to the year-Iong operation of existing nuclear reactors and it will eventually also be generated during the running of new reactor types - albeit they can be optimized to produce much less of it. Research to the aim of finding techniques optimized for a strong reduction of nuclear waste can already be performed at existing nuclear facilities from the consortium proposed in this proposal. The main objective is to provide adequate transnational access to the infrastructures. The consortium will also provide funding for scientific support of experiments by short term visits of scientist to the participating facilities and foster the communication and disseminaton of the results by organising scientific workshops.

Impact of Village Resettlement on Wildlife Conservation in Cameroon

The number of protected areas in our planet has multiplied as an outcome of the Rio Conference in 1992 which declared the conservation of biodiversity and creation of national parks as priority. However, particularly in central Africa, the establishment of protected areas has resulted in a wide spread displacement of human populations. The issue of resettlement is still much-debated in International discussions. Is the resettlement of 'forest people worthwhile as a conservation strategy in protecting populations of large mammals which are under risk of extinction through hunting? Some schools of thought contend that conventional conservation strategies such as the resettlement of the 'forest people out of National Parks can be regarded as tantamount to abuse of human rights and also altering local livelihood aspects of the village communities for the sake of wildlife and biodiversity. Hitherto, despite much criticism of the displacement of indigenous poor communities, very few studies have researched the possible positive outcomes of resettlement from protected areas. Resettlement therefore, has been a delicate option in conservation planning in most parts of the world due to its socio-economic, political and environmental ramifications. The multifarious challenges faced by the resettled populations make the question of re-settlement of other villages all the more difficult. Using a case study from south west Cameroon, this project examines the outcome of a government initiative to safeguard wildlife following the creation of the Korup National Park through a progressive resettlement scheme of the Ekundukundu Village out of the 'protected zone'. It seeks to ascertain whether the approach in resettling and re-orientating the daily lives of forest dwellers away from their traditional milieu can be a successful method of safeguarding wildlife in our forests. It also complies with the call for an assessment of ''the economic and socio-cultural costs and impacts arising from the establishment and maintenance of protected areas (CBD COP7 2004).

Entwicklung von Pflanzenschutzstrategien im ökologischen Hopfenbau als Alternativen zur Anwendung kupfer- und schwefelhaltiger Pflanzenschutzmittel

Die wichtigsten Krankheiten des Hopfens sind der Falsche Mehltau (Peronospora) und der Echte Mehltau. Aufgabe des Forschungsprojektes war es, Wirkstoffe beziehungsweise Methoden zu finden, die zur Bekämpfung dieser Krankheiten die allgemein verwendeten kupfer- und schwefelhaltigen Produkte ersetzen können. Da die Bekämpfung der Hopfenblattlaus im Öko-Hopfenbau ein besonderes Problem darstellt, wurden auch Versuche zu diesem Schädling angelegt und ausgewertet. Alle Versuche wurden über drei Jahre von 2004-2006 in Öko-Hopfenbaubetrieben im Anbaugebiet der Hallertau durchgeführt. Als Vergleich dienten immer unbehandelte Parzellen. Grundsätzlich stellen die Abnehmer von Öko-Hopfen die gleichen Qualitätsanforderungen an die Hopfendolden wie es im konventionellen Markt gefordert wird. Trotz Anbau von überwiegend toleranten Sorten, der Nutzung von Prognosemodellen und der Berücksichtigung der Nützlingsschonung ist auch im Öko-Anbau der Einsatz von Pflanzenschutzmitteln notwendig. Zur Bekämpfung des Falschen Mehltaus wurden die rein biologischen Mittel 'Kanne Brottrunk, 'Molke, 'FungEnd + Öle sowie ein Testprodukt der Firma 'Stähler eingesetzt. Im ersten Versuchsjahr kam auch das Handelsprodukt 'Frutogard zum Einsatz, das, wie sich später herausstellte, allerdings Phosphit enthält und deshalb im Ökobetrieb nicht eingesetzt werden kann. Als kupferhaltige Varianten wurden Funguran, Cuprozin flüssig und das Entwicklungsprodukt DPD GF J52-008 getestet. Nach Abschluss der Prüfung muss festgestellt werden, dass bei der anfälligen Testsorte alle rein biologischen Varianten zu keinem Erfolg führten. Auch die Produkte mit niedrigerem Kupfergehalt waren nicht immer erfolgreich. Mit Abstand am Besten hat eine 'betriebseigene Mischung von Kupfer, Schwefel, Gesteinsmehl und effektiven Mikroorganismen abgeschnitten. Zu den Prüfmitteln gegen Echten Mehltau kann keine Aussage getroffen werden, da diese Krankheit während der gesamten Versuchsdauer in den unbehandelten Parzellen nicht vorkam. Zur Blattlausbekämpfung wurden Mittel auf rein pflanzlicher Basis (Spruzit Neu, Quassia- Extrakt, NeemAzal T/S und TRF-002, mit Quassin als Wirkstoff) eingesetzt. Neben der praxisüblichen Spritzung wurden mit Ausnahme von Spruzit Neu die Wirkstoffe in zusätzlichen Varianten während der Hauptwachstumsphase des Hopfens mit einem Pinsel auf die Reben gestrichen. 10 Es konnte mit dieser Methode erstmals nachgewiesen werden, dass die Wirkstoffe von NeemAzal T/S und Quassia (bzw. im Fertigprodukt TRF-002) von der Pflanze in den Leitungsbahnen systemisch nach oben bis in sieben Meter Höhe transportiert werden. Insgesamt die besten Wirkungen brachten Quassia-Extrakt gespritzt und TRF-002 mit einer Wirkstoffmenge von 24 g Quassin pro Hektar. Über alle Versuche betrachtet, konnten NeemAzal T/S und Spruzit Neu nicht befriedigen. Die Streichvariante TRF-002 mit 24 g Quassin/ha ist praxistauglich; eine Genehmigung nach dem Pflanzenschutzgesetz sollte angestrebt werden.

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