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3R-Studie - Reduce, Reuse, Recycle für die G8-Staaten

bifa hat ein Vorhaben für die G8- Staaten bearbeitet, in dem die Entwicklungen in Deutschland innerhalb der neun Handlungsfelder ( Actions ) des Kobe 3R Action Plan dargestellt werden. Mit der 3R-Initiative beabsichtigen die G8-Staaten seit 2004 eine bessere Verankerung der Nachhaltigkeit im Umgang mit Rohstoffen durch die stärkere Förderung der drei Prinzipien Reduce, Reuse, Recycle , abgekürzt 3R , in den nationalen Abfallwirtschaftspolitiken. Im Rahmen der Beauftragung untersuchte bifa, welche Punkte aus dem Kobe 3R Action Plan bereits hinreichend durch bestehende Entwicklungen bzw. ergriffene Maßnahmen abgedeckt sind, bei welchen Aktionen noch Lücken bestehen und wie diese Lücken gefüllt werden können. Legt man die drei Zielsetzungen des Kobe 3R Action Plan und die ihnen zugeordneten Handlungsfelder als Prüfraster über die deutsche Abfallwirtschaftspolitik, lässt sich ein sehr hoher Erfüllungsgrad feststellen. Ein erheblicher Teil der vorgeschlagenen Handlungsoptionen war in Deutschland bereits vor 2008 durch konkrete Maßnahmen umgesetzt worden. Für einen anderen Teil wiederum lässt sich der Ursprung, z. B. in Form eines ersten Gesetzentwurfs, auf die Zeit vor 2008 zurückdatieren, die Umsetzung durch die Veröffentlichung im Bundesgesetzblatt aber fand 2008-2011 statt. Einige Regelungen setzen Richtlinien oder Verordnungen der EU, die ihrerseits zum Teil auf Bestrebungen Deutschlands hin zustande kamen, in nationales Recht um. Mit dem in einer fortgeschrittenen Version vorliegenden Entwurf eines novellierten Kreislaufwirtschaftsgesetzes vollzieht Deutschland einen weiteren wichtigen Schritt hin zu einer Abfallwirtschaft, deren Markenzeichen insbesondere eine hohe Ressourceneffizienz ist. Dennoch verbleiben Optimierungspotenziale, zu deren Ausschöpfung bifa Vorschläge für das Bundesumweltministerium erarbeitet hat. Im Zuge des Projekts analysierte bifa u. a. die Importe und Exporte notifizierungspflichtiger Abfälle. Der Saldo hat sich den bifa-Analysen zufolge seit 1998 umgekehrt: Wurden 1998 noch etwa doppelt so viel notifizierungspflichtige Abfälle exportiert wie importiert, hat sich der Import seitdem vervierfacht und die Exporte sind sogar leicht gesunken. Ein wichtiger Grund ist die Verfügbarkeit von Behandlungs- und Verwertungskapazitäten von hoher Leistungsfähigkeit in Deutschland. Die Schadstoffentfrachtung von Abfällen aus Ländern mit einer wenig entwickelten Entsorgungsinfrastruktur führt jedoch innerhalb der deutschen Öffentlichkeit immer wieder zu Kontroversen. Methoden: Analyse und Moderation sozialer Prozesse.

Coordination and administration of the priority programme SPP 1315 Biogeochemical Interfaces in Soil, Biotic and abiotic factors that dive the function of microbial communities at biogeochemical interfaces in different soils (BAMISO)

Biogeochemical interfaces shape microbial community function in soil. On the other hand microbial communities influence the properties of biogeochemical interfaces. Despite the importance of this interplay, basic understanding of the role of biogeochemical interfaces for microbial performance is still missing. We postulate that biogeochemical interfaces in soil are important for the formation of functional consortia of microorganisms, which are able to shape their own microenvironment and therefore influence the properties of interfaces in soil. Furthermore biogeochemical interfaces act as genetic memory of soils, as they can store DNA from dead microbes and protect it from degradation. We propose that for the formation of functional biogeochemical interfaces microbial dispersal (e.g. along fungal networks) in response to quality and quantity of bioavailable carbon and/or water availability plays a major role, as the development of functional guilds of microbes requires energy and depends on the redox state of the habitat.To address these questions, hexadecane degradation will be studied in differently developed artificial and natural soils. To answer the question on the role of carbon quantity and quality, experiments will be performed with and without litter material at different water contents of the soil. Experiments will be performed with intact soil columns as well as soil samples where the developed interface structure has been artificially destroyed. Molecular analysis of hexadecane degrading microbial communties will be done in vitro as well as in situ. The corresponding toolbox has been successfully developed in the first phase of the priority program including methods for genome, transcriptome and proteome analysis.

Quantification of small-scale physicochemical properties of intact macropore surfaces in structured soils

In structured soils, the interaction of percolating water and reactive solutes with the soil matrix is mostly restricted to the surfaces of preferential flow paths. Flow paths, i.e., macropores, are formed by worm burrows, decayed root channels, cracks, and inter-aggregate spaces. While biopores are covered by earthworm casts and mucilage or by root residues, aggregates and cracks are often coated by soil organic matter (SOM), oxides, and clay minerals especially in the clay illuviation horizons of Luvisols. The SOM as well as the clay mineral composition and concentration strongly determine the wettability and sorption capacity of the coatings and thus control water and solute movement as well as the mass exchange between the preferential flow paths and the soil matrix. The objective of this proposal is the quantitative description of the small-scale distribution of physicochemical properties of intact structural surfaces and flow path surfaces and of their distribution in the soil volume. Samples of Bt horizons of Luvisols from Loess will be compared with those from glacial till. At intact structural surfaces prepared from soil clods, the spatial distribution (mm-scale) of SOM and clay mineral composition will be characterized with DRIFT (Diffuse reflectance infrared Fourier transform) spectroscopy using a self-developed mapping technique. For samples manually separated from coated surfaces and biopore walls, the contents of organic carbon (Corg) and the cation exchange capacity (CEC) will be analyzed and related to the intensities of specific signals in DRIFT spectra using Partial Least Square Regression (PLSR) analysis. The signal intensities of the DRIFT mapping spectra will be used to quantify the spatial distribution of Corg and CEC at these structural surfaces. The DRIFT mapping data will also be used for qualitatively characterizing the small scale distribution of the recalcitrance, humification, and microbial activity of the SOM from structural surfaces. The clay mineral composition of defined surface regions will be characterized by combining DRIFT spectroscopic with X-ray diffractometric analysis of manually separated samples. Subsequently, the spatial distribution of the clay mineral composition at structural surfaces will be determined from the intensities of clay mineral-specific signals in the DRIFT mapping spectra and exemplarily compared to scanning electron microscopic and infrared microscopic analysis of thin sections and thin polished micro-sections. The three-dimensional spatial distribution of the total structural surfaces in the volume of the Bt horizons will be quantified using X-ray computed tomography (CT) analysis of soil cores. The active preferential flow paths will be visualized and quantified by field tracer experiments. These CT and tracer data will be used to transfer the properties of the structural surfaces characterized by DRIFT mapping onto the active preferential flow paths in the Bt horizons.

Root distribution and dynamics and their contribution to subsoil C-fluxes

It has been suggested that dying and decaying fine roots and root exudation represent important, if not the most important, sources of soil organic carbon (SOC) in forest soils. This may be especially true for deep-reaching roots in the subsoil, but precise data to prove this assumption are lacking. This subproject (1) examines the distribution and abundance of fine roots (greater than 2 mm diameter) and coarse roots (greater than 2 mm) in the subsoil to 240 cm depth of the three subsoil observatories in a mature European beech (Fagus sylvatica) stand, (2) quantifies the turnover of beech fine roots by direct observation (mini-rhizotron approach), (3) measures the decomposition of dead fine root mass in different soil depths, and (4) quantifies root exudation and the N-uptake potential with novel techniques under in situ conditions with the aim (i) to quantify the C flux to the SOC pool upon root death in the subsoil, (ii) to obtain a quantitative estimate of root exudation in the subsoil, and (iii) to assess the uptake activity of fine roots in the subsoil as compared to roots in the topsoil. Key methods applied are (a) the microscopic distinction between live and dead fine root mass, (b) the estimation of fine and coarse root age by the 14C bomb approach and annual ring counting in roots, (c) the direct observation of the formation and disappearance of fine roots in rhizotron tubes by sequential root imaging (CI-600 system, CID) and the calculation of root turnover, (d) the measurement of root litter decomposition using litter bags under field and controlled laboratory conditions, (e) the estimation of root N-uptake capacity by exposing intact fine roots to 15NH4+ and 15NO3- solutions, and (f) the measurement of root exudation by exposing intact fine root branches to trap solutions in cuvettes in the field and analysing for carbohydrates and amino acids by HPLC and Py-FIMS (cooperation with Prof. A. Fischer, University of Trier). The obtained data will be analysed for differences in root abundance and activity between subsoil (100-200 cm) and topsoil (0-20 cm) and will be related to soil chemical and soil biological data collected by the partner projects that may control root turnover and exudation in the subsoil. In a supplementary study, fine root biomass distribution and root turnover will also be studied at the four additional beech sites for examining root-borne C fluxes in the subsoil of beech forests under contrasting soil conditions of different geological substrates (Triassic limestone and sandstone, Quaternary sand and loess deposits).

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.

Impact of Intrafollicular Sulfated Steroids on Follicular Cells and the Oocyte's Developmental Capacity in Cattle

Steroid hormones are essential in orchestrating oocyte maturation, i.e. estrogens of follicular origin support the development of the female gamete and fertilization. In this project the concentration of free and conjugated estrogens during follicular development will be analysed and compared to local concentrations in the developing follicle. Cattle are suitable animal models because of the accessibility and suitability for frequent examination and sampling. Furthermore, it has been useful for understanding several features of human reproduction including follicular dynamics, the fate of the emerging follicles is orchestrated mainly by gonadotropins and steroid hormones in a similar manner. Ovarian SULT1E1 participates locally in the regulation of follicular estrogen activity. The ESTcatalysed down-regulation of estrogen activity enables normal ovulation. Conversely, sulfoconjugated estrogens may also be precursors of the production of free estrogens depending on estrogen sulfatase (StS) acitivity. In mammals, follicular luteinisation/ovulation is triggered by a surge in LH and is characterised by numerous physical and biochemical changes, including the decreased production of estradiol (E2). This loss in E2 biosynthetic capacity has been explained by a marked decrease in the expression of key steroidogenic enzymes involved in the follicular production of active estrogens. However, little is known about the regulation of enzymes/proteins responsible for the inactivation and elimination of estrogens, as mediated for example by EST during this period.

Redox processes along gradients

The relevance of biogeochemical gradients for turnover of organic matter and contaminants is yet poorly understood. This study aims at the identification and quantification of the interaction of different redox processes along gradients. The interaction of iron-, and sulfate reduction and methanogenesis will be studied in controlled batch and column experiments. Factors constraining the accessibility and the energy yield from the use of these electron acceptors will be evaluated, such as passivation of iron oxides, re-oxidation of hydrogen sulfide on iron oxides. The impact of these constraints on the competitiveness of the particular process will then be described. Special focus will be put on the evolution of methanogenic conditions in systems formerly characterized by iron and sulfate reducing condition. As methanogenic conditions mostly evolve from micro-niches, methods to study the existence, evolution and stability of such micro-niches will be established. To this end, a combination of Gibbs free energy calculations, isotope fractionation and tracer measurements, and mass balances of metabolic intermediates (small pool sizes) and end products (large pool sizes) will be used. Measurements of these parameters on different scales using microelectrodes (mm scale), micro sampling devices for solutes and gases (cm scale) and mass flow balancing (column/reactor scale) will be compared to characterize unit volumes for organic matter degradation pathways and electron flow. Of particular interest will be the impact of redox active humic substances on the competitiveness of involved terminal electron accepting processes, either acting as electron shuttles or directly providing electron accepting capacity. This will be studied using fluorescence spectroscopy and parallel factor analysis (PARAFAC) of the gained spectra. We expect that the results will provide a basis for improving reactive transport models of anaerobic processes in aquifers and sediments.

Nachbewilligung zur Dritten Phase des Projektes: Entwicklung eines zweistufigen biologischen Verfahrens zur Reinigung von Deponiesickerwasser und industriellen Abwässern mit komplexen Stoffgemischen

Zielsetzung und Anlass des Vorhabens: Ziel der letzten Projektphase war es, mit einer Langzeit-Praxiserprobung das zweistufige biologische Verfahren zur Deponiesickerwasserreinigung als Stand der Technik zu etablieren und zu bilanzieren. Nach der Inbetriebnahme des Technikums am Deponiestandort Schöneiche ging es in der zwölfmonatigen Laufzeit des Projektes AZ 14996/04 in den Langzeitversuchen um die Validierung der Laborergebnisse im technischen Maßstab, die verfahrenstechnische Optimierung der Anlage und um eine damit verbundene mögliche Kostenreduzierung des Systems. Darstellung der Arbeitsschritte und der angewandten Methoden: Nach dem ersten Technikums-Probebetrieb wurde eine Reihe von Optimierungsmaßnahmen durchgeführt: - der Umbau des Rohsickerwasserzulaufs, - die Verwendung von Soda statt Bicarbonat für die Ammoniumoxidation in Reaktor 2, - der Einsatz von Membrandosierpumpen mit integrierten Rückschlagventilen für die Zugabe von Soda und Essigsäure, - der Einbau von zusätzlichen Polyurethan-Festbetten zur Vergrößerung der Oberfläche für die Besiedlung mit Mikroorganismen, - die Einstellung des Sollwerts für Reaktor 4 auf einen pH-Wert von 6,5, - ein Update der SPS-Steuerung der Nanofiltration zur freien Programmierung der Spülzyklen, - der Einbau eines Absperrhahns vor den Nanofiltrations-Vorfilter - und die Trennung des Nanofiltrationsablaufs vom Reaktoren-Sammelablauf zur Behälterleerung. Es wurde sowohl Rohsickerwasser der MEAB-Deponie Schöneiche als auch Sickerwasserkonzentrat der Deponie Vorketzin behandelt. Fazit: Wegen der durchgeführten Optimierungsmaßnahmen ist es prinzipiell gelungen, das Schöneicher Rohsickerwasser gemäß Anhang 51 der Abwasserverordnung aufzureinigen. In Vorketzin wurde die organische Belastung über 70% und Stickstoff über 80% reduziert. Nach Rückgang der Calciumfracht sollte es zukünftig möglich sein, mit der Zweistufen-Biologie das Sickerwasserkonzentrat ausreichend zu reinigen, da organische Belastung und Stickstoffgehalt geringer als im Schöneicher Rohsickerwasser sind. Um das Verfahren als Stand der Technik, vor allem für die Behandlung von Sickerwasserkonzentraten, zu etablieren, müssten die Laborvorgaben mit den Erfahrungen des Technikumsbetriebs kombiniert und in einer weiteren Versuchsreihe unter optimierten Bedingungen verifiziert werden.

Optimierung des Umsetzungsgrades von Solarabsorbern mit hochselektiver Oberflaeche

Erhoehung des energetischen Outputs von Solarabsorbern durch Variation des Aufbaues und der verwendeten Materialien. Minimierung der Verlustleistung.

Ecosystem Engineering: Sediment entrainment and flocculation mediated by microbial produced extracellular polymeric substances (EPS)

Sediment erosion and transport is critical to the ecological and commercial health of aquatic habitats from watershed to sea. There is now a consensus that microorganisms inhabiting the system mediate the erosive response of natural sediments ('ecosystem engineers') along with physicochemical properties. The biological mechanism is through secretion of a microbial organic glue (EPS: extracellular polymeric substances) that enhances binding forces between sediment grains to impact sediment stability and post-entrainment flocculation. The proposed work will elucidate the functional capability of heterotrophic bacteria, cyanobacteria and eukaryotic microalgae for mediating freshwater sediments to influence sediment erosion and transport. The potential and relevance of natural biofilms to provide this important 'ecosystem service' will be investigated for different niches in a freshwater habitat. Thereby, variations of the EPS 'quality' and 'quantity' to influence cohesion within sediments and flocs will be related to shifts in biofilm composition, sediment characteristics (e.g. organic background) and varying abiotic conditions (e.g. light, hydrodynamic regime) in the water body. Thus, the proposed interdisciplinary work will contribute to a conceptual understanding of microbial sediment engineering that represents an important ecosystem function in freshwater habitats. The research has wide implications for the water framework directive and sediment management strategies.

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