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Umweltprobenbank des Bundes (German Environmental Specimen Bank)

Die Umweltprobenbank des Bundes (UPB) mit ihren Bereichen Bank für Umweltproben und Bank für Humanproben ist eine Daueraufgabe des Bundes unter der Gesamtverantwortung des Bundesumweltministeriums sowie der administrativen und fachlichen Koordinierung des Umweltbundesamtes. Es werden für die Bank für Umweltproben regelmäßig Tier- und Pflanzenproben aus repräsentativen Ökosystemen (marin, limnisch und terrestrisch) Deutschlands und darüber hinaus für die Bank für Humanproben im Rahmen einer Echtzeitanalyse Blut-, Urin-, Speichel- und Haarproben studentischer Kollektive gewonnen. Vor ihrer Einlagerung werden die Proben auf eine Vielzahl an umweltrelevanten Stoffen und Verbindungen (z.B. Schwermetalle, CKW und PAH) analysiert. Der eigentliche Wert der Umweltprobenbank besteht jedoch in der Archivierung der Proben. Sie werden chemisch veränderungsfrei (über Flüssigstickstoff) gelagert und somit können auch rückblickend Stoffe untersucht werden, die zum Zeitpunkt ihrer Einwirkung noch nicht bekannt oder analysierbar waren oder für nicht bedeutsam gehalten wurden. Alle im Betrieb der Umweltprobenbank anfallenden Daten und Informationen werden mit einem Datenbankmanagementsystem verwaltet und aufbereitet. Hierbei handelt es sich insbesondere um die biometrischen und analytischen Daten, das Schlüsselsystem der UPB, die Probenahmepläne, die Standardarbeitsanweisungen (SOP) zu Probenahme, Transport, Aufbereitung, Lagerung und Analytik und die Lagerbestandsdaten. Mit einem Geo-Informationssystem werden die Karten der Probenahmegebiete erstellt, mit denen perspektivisch eine Verknüpfung der analytischen Ergebnisse mit den biometrischen Daten sowie weiteren geoökologischen Daten (z.B. Daten der Flächennutzung, der Bodenökologie, der Klimatologie) erfolgen soll. Ausführliche Informationen und eine umfassende Datenrecherche sind unter www.umweltprobenbank.de abrufbar.

Metallspeziesanalyse in hochkontaminierten Böden - Untersuchung und Validierung (sequentieller) Extraktionsmethoden durch instrumentelle Analysemethoden

Das Projekt "Metallspeziesanalyse in hochkontaminierten Böden - Untersuchung und Validierung (sequentieller) Extraktionsmethoden durch instrumentelle Analysemethoden" wird vom Umweltbundesamt gefördert und von Technische Universität Hamburg-Harburg, Arbeitsbereich 1-03 Umweltschutztechnik durchgeführt. Sequentielle Extraktionsmethoden oder single-step-Extraktionen stellen ein häufig genutztes Instrumentarium zur Bewertung von Schwermetallkontaminationen in Sedimenten, Böden oder Reststoffen dar. Im wesentlichen geht es bei den Extraktionen um die Differenzierung mehr oder minder leicht löslicher Anteile des Gesamtmetallgehaltes, um eine Abschätzung des chemischen Verhaltens bei wechselnden Umweltbedingungen sowie um eine Prognose des Langzeitverhaltens der in der Probe befindlichen Schwermetalle. Aus analytisch-chemischer Sicht stellt sich die Frage nach der Aussagekraft solcher Methoden. Da sie einerseits schnell, preiswert und einfach durchzuführen sind, bieten sie eine attraktive Alternative zu aufwendigen instrumentellen Methoden. Andererseits kann es während sequentieller Extraktionen - gerade bei hochkontaminierten Böden (g kg-1-Bereich) - zu gravierenden Veränderungen der Proben kommen, die zu Falschaussagen führen. Im beantragten Projekt sollen verschiedene Extraktionsmethoden mittels instrumenteller, speziesanalytischer Methoden systematisch untersucht werden. Zum Einsatz kommen die XAFS-Spektroskopie sowie mikroanalytische Methoden (REM/EDX). Die Untersuchungen werden an einer Anzahl hochkontaminierter Bodenproben (Pb, Cu, Cr) durchgeführt.

Spaltproduktfreisetzung und -spezifikation

Das Projekt "Spaltproduktfreisetzung und -spezifikation" wird vom Umweltbundesamt gefördert und von Universität Bochum, Fakultät XIII für Maschinenbau, Institut für Energietechnik, Lehrstuhl für Nukleare und Neue Energiesysteme durchgeführt. Ziel des von mehreren europaeischen Institutionen bearbeiteten Projektes ist die Analyse der chemischen Form freigesetzter Spaltprodukte (Spezifikation) sowie deren Freisetzungsverhalten aus einem zerstoerten Reaktorkern. Dabei sind experimentelle Arbeiten mit theoretischen Studien zur Validierung und Verbesserung bestehender Modellansaetze gekoppelt. Im Rahmen dieses Projektes analysiert RUB/NES - mit Blick auf eine Modellvalidierung - ausgewaehlte Experimente zur Freisetzung von Spaltprodukten aus Kernschmelzen mit Hilfe des Programms RELOS (RElease of LOw volatile fission products from molten pool Surfaces). Das innerhalb der Arbeiten zum Projekt 'Freisetzung schwer fluechtiger Spaltprodukte aus Kernschmelzen' des 3. Rahmenprogramms der EU entwickelte Programm dient der Bestimmung des diffusiven und konvektiven Transportes der Spaltprodukte von einer fluessigen Schmelzeoberflaeche in die darueberliegende kaeltere Gasphase. Es basiert auf einem mechanistischen Transportmodell und thermochemischen Ansaetzen.

Impact of colloidal organic matter on toxic metal bioavailability in urban water cycle

Das Projekt "Impact of colloidal organic matter on toxic metal bioavailability in urban water cycle" wird vom Umweltbundesamt gefördert und von Ecole Polytechnique Federale de Lausanne (EPF), Environmental Biophysical Chemistry Group durchgeführt. Urban waters are important vectors of xenobiotics (e.g. heavy metals and organic pollutants) towards aquatic environments and their potential toxicity to the receiving waters is of concern. Although it is accepted that pollutant chemical forms have different fate and environmental impact, there are paucity of data concerning the chemical speciation and biouptake of toxic metals in the urban waters. The present project therefore addresses the key issue of linking the speciation and biouptake of priority metal pollutants in urban waters, and in particular the role of the colloidal orga-nic matter (COM). Binding of metals by COM was examined by ion exchange speciation technique in parallel to bioassays with green microalga Chlorella kesslerii. To explore how the size and molar mass distribitions of COM affect their behaviour and metal binding properties, COM and associated toxic metals were also fractionated and characterized by Flow field flow fractionation - multidetection platform, including on-line detection with multiangle laser light scattering, UV, RI and ICP-MS. Final effluents of the waste water treatment plants (WWTP) of Duebendorf, Hinwill and Zurich were sampled in two field trips organized in January 2007 and in February 2008. In both campaigns, determined total and dissolved metal concentrations were below the limits fixed by the water quality directives for surface waters in Switzerland (Oeaux). Humic - like substances of low specific ab-sorption properties and average molar masses between ca. 1000 and 3600 Da were identified as the major colloidal fraction components of the WWTP COM. Significant proportions of metals such Cu, Ni, Zn and Cr were associated to the low molar mass colloidal fractions, and are thus expected to have longer residence time in water than particulate fraction. Interestingly Pb binds preferentially to high molar mass COM, also containing Fe and Al. Furthermore, the uptake of Cd and Cu by alga Chlorella kesslerii was consistent to the speciation analysis and measured free metal ion concentrations, while Pb uptake was larger than that expected from the speciation measurement. These results suggest that the uptake (and potential toxic effect) of Cd and Cu in urban waters can be predicted by the speciation measurements and modelling (e.g. by the biotic ligand model that is currently been used by EPA in USA). In the case of Pb, the interactions of the colloidal organic matter with algae should be taken into account in addition to the chemical speciation.

Arsenic contamination of Ogosta river: Linking biogeochemical processes in floodplain soils with river system dynamics

Das Projekt "Arsenic contamination of Ogosta river: Linking biogeochemical processes in floodplain soils with river system dynamics" wird vom Umweltbundesamt gefördert und von Eidgenössische Technische Hochschule Zürich, Institut für Biogeochemie und Schadstoffdynamik durchgeführt. The sustainable management of land, which has been heavily contaminated by industrial or mining activities, poses an important challenge to many industrialized countries, including Bulgaria. This project focuses on arsenic (As) contamination in NW Bulgaria, where the floodplains of the Ogosta river received large amounts of As-rich mining wastes near Chiprovtsi between 1964 and 1979. The goals of the project are (i) to investigate the magnitude and spatial distribution of As contamination in floodplain soils and sediments in relation to river system dynamics, (ii) to improve the process-oriented understanding of As release from soils to river and groundwater by microbial and physico-chemical processes during periods of low and high flow, and (iii) to explore advanced approaches for integrating process-oriented, molecular scale knowledge and river-system scale information to better understand As speciation, As fluxes, and impacts on water quality at the river-system scale. The project is expected to yield novel process-oriented knowledge on the dynamics of As in highly contaminated river floodplains. New ways of integrating molecular-scale and river-system scale information will be explored, which can then also be applied to other river systems in Bulgaria. The project will provide the scientific basis for river management and potential remediation strategies for Ogosta river. Ultimately, it will help protect the local population from adverse health effects arising from the legacy pollution with As and other heavy metals by former mining.

Bestimmung von Staubpartikeln durch Laser-Technik (Mikrosonde) in Verbindung mit Massenspektrometrie (Lamma)

Das Projekt "Bestimmung von Staubpartikeln durch Laser-Technik (Mikrosonde) in Verbindung mit Massenspektrometrie (Lamma)" wird vom Umweltbundesamt gefördert und von Canton de Geneve, Institut d'Hygiene, Service de toxicologie industrielle durchgeführt. Mise au point d'une methodologie permettant de faire la speciation des poussieres par lamma (laser microprobe mass analyser). Etude de la fragmentation et de la formation des ions apres impact du rayonnement laser, ceci dans le but de faire l'identification des particules minerales sous leur forme moleculaire. (FRA)

Evolutionary Conflicts and their Impact on Speciation

Das Projekt "Evolutionary Conflicts and their Impact on Speciation" wird vom Umweltbundesamt gefördert und von Eidgenössische Technische Hochschule Zürich, Institut für Integrative Biologie durchgeführt. Within the general framework of evolutionary theory, I am particularly interested in sexual selection and evolutionary conflicts within and between species (sexual and host-parasite conflicts) as potential drivers of speciation. Reproductive barriers between populations are of crucial importance as they can help explain how new species are formed and what factors encourage or constrain biodiversity. Reproductive traits are known to be susceptible to very rapid evolutionary change yet the exact traits responsible for reproductive isolation generally remain unclear. I aim to identify such traits and understand how they diverge and affect reproductive barriers between populations in Tribolium flour beetles (important pests of stored products and genetically tractable model organisms). I will mainly use a powerful long-term 'experimental evolution' approach to examine whether sexual selection generates greater differences in reproductive traits and accelerates reproductive isolation. To do this, I will be using different populations maintained under different levels of sexual selection (through variation in the intensity of competition between males to produce offspring). In addition to detailed experimental studies of a range of reproductive characters and the impact of endosymbionts on host reproduction, I will run a combined experimental evolution experiment incorporating different levels of sexual selection and status of infection (infected vs. uninfected). This will enable me to judge how both sexual selection and reproductive parasites (such as the bacterial endosymbiont Wolbachia) impact on speciation. Despite strong theoretical support, the importance of sexual selection and evolutionary conflicts as speciation engines remains controversial and hence generates intense debate. This research aims to establish whether these forces can act singly or combined to accelerate speciation (and ultimately generate biodiversity) and their overall and relative importance as engines of speciation. This will be of particular interest to scientists working in the fields of evolutionary biology and behavioural ecology, but also to ecologists, reproductive biologists, and conservation biologists. Because Tribolium beetles are agricultural pests of considerable economic importance, results will also be relevant to more applied researchers. Moreover, as endosymbionts could have potential applications as biocontrol agents for pests or insect vectors of disease, it is critical that detailed knowledge of consequences for the host of infection with the symbiont is available.

Evolutionary Conflicts and their Impact on Speciation (follow-up)

Das Projekt "Evolutionary Conflicts and their Impact on Speciation (follow-up)" wird vom Umweltbundesamt gefördert und von Eidgenössische Technische Hochschule Zürich, Institut für Integrative Biologie durchgeführt. In addition to recognizing natural selection as a universal mechanism in evolution, Darwin also saw the importance of sexual selection, yet the two have been traditionally treated largely in isolation. Here I propose to apply experimental evolution (exposing experimental populations to controlled specific selective pressures over many generations in the laboratory) to the ideally suited model system Tribolium castaneum to explore how these evolutionary forces interact and impact on the key processes underlying biodiversity. Understanding how these fundamental forces, singly and in conjunction, influence species divergence remains a major challenge in evolutionary biology. Participation of sexual selection in driving speciation is supported by substantial theoretical evidence. Theory further suggests that evolutionary conflicts (such as between the sexes or between host and parasite) might also accelerate extinction. Additional complexity is introduced by including the environmental context, linking back to natural selection. Direct experimental tests of the above concepts are essentially lacking. I will explicitly target this gap by exploiting powerful experimental evolution, incorporating the interplay between sexual selection intensity, host-parasite conflict, and adaptation to increasing temperature. Projects will assess how selection under evolutionary conflict and environmental change affects both adaptation and extinction rates, aiming to elucidate underlying mechanisms. Additionally, building on clear phenotypic divergence in key traits across experimental evolution lines, I will significantly expand on previous work by assessing patterns of divergence in gene expression, concentrating on target genes associated with reproduction, immunity and heat shock. This research will be of particular interest to scientists working in the fields of evolutionary biology and behavioural ecology, but also to ecologists, reproductive biologists, and conservation biologists. As Tribolium beetles are widespread agricultural pests, results will also be relevant to more applied researchers.

Genome dynamics and plant speciation: Spatio-temporal evolution of genetic barriers under changing climate

Das Projekt "Genome dynamics and plant speciation: Spatio-temporal evolution of genetic barriers under changing climate" wird vom Umweltbundesamt gefördert und von University Oslo durchgeführt. How new species arise is a central question in biology, and how climate change affects speciation is currently a key question. Our understanding of the molecular mechanisms underlying the origin of reproductive barriers among infraspecific populations is a highly debated topic. However, in contrast to the situation in animals, some evidence suggests that new plant species commonly evolve in response to chromosomal rearrangements. Since plant genomes are remarkably dynamic, probably in relation to their high content in transposable elements, it is a timely task to investigate the way genome responds to climate change and whether this translates into the origin of new species. To expand the knowledge about the origin of species, the present project aims at addressing whether microchromosomal rearrangements, and particularly those related to transposable elements, stimulate intrinsic postzygotic isolation in plants. This is best done in an explicit spatiotemporal framework including changing climate as a potential environmental cue. Accordingly, the origin of cryptic biological species within the circumpolar plant Draba nivalis will be dissected by scoring quantitative trait loci (QTL) for sterility in populations grown from reciprocal incompatible crosses, using both Amplified Fragment Length Polymorphism (AFLP) and Sequence-Specific Amplified Polymorphism (SSAP, marking insertions of transposable elements). In order to further analyse the genetic factors involved in the quick rise of reproductive barriers, these sterility QTLs will be characterised by massively sequencing the AFLP/SSAP markers in parallel. Finally, a comparative phylogeograhic analysis of the sterility QTLs and neutral non-QTL markers will allow to reconstruct the history of reproductive barriers, assessing the corresponding evolutionary processes underlying the recent speciation in D. nivalis during the ice age.

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