Der Kartendienst (WFS-Gruppe) stellt die Standorte der öffentlichen Landesverwaltung und der Kommunen dar.:Bibliotheken im Saarland
Iron(III) (hydr)oxide-organic associations in soils have been recognized to play an important role in the biogeochemical cycling of iron, carbon, and of nutrients like phosphate. In temporarily moist or water-logged soils such associations can form via the coprecipitation of dissolved organic matter (OM) with Fe(III) (hydr)oxides (FHOs). At present, it is generally unknown which factors control the formation and composition of Fe(III)-OM coprecipitates and how the structural properties translate into the cycling of the FHO and OM component involved. The objectives of the project are thus to elucidate (i) the structural properties of Fe(III)- OM coprecipitates under different environmental conditions, (ii) the subsequent stability of Fe(III)-OM coprecipitates against dissolution under both oxic as well as anoxic conditions, (iii) the changes in Fe(III)-OM coprecipitate composition upon redox oscillations, and (iii) their cumulative effects on oxyanion sorption. To achieve these goals, various batch experiments will be conducted. By using multiple analytical tools, this project will gain a fundamental understanding of the abiotic and biotic controls on the formation, structure, and biogeochemical reactivity of Fe(III)-OM coprecipitates in acidic and neutral temporarily moist soils and soils subject to redox oscillations.
Beschreibung des INSPIRE Download Service (predefined Atom): Büchereien und Bibliotheken Saarland wurden anhand von Listen vom Ministerium für Bildung und Kultur in den Kategorien, Konfessionelle öffentliche Bibliotheken, Kommunale öffentliche Bibliotheken, Wissenschaftliche und Spezial-Bibliotheken erfasst. Attributtabelle: KREIS-----------: Kreisziffer RW---------------: Rechtswert HW---------------: Hochwert PLZ---------------: Postleitzahl ORT_NAME-----: Ortsname POST_ORT------: Post Anschrift STR_NAME-----: Straßenname HNR--------------: Hausnummer ADZ--------------: Adressenzusatz NAME DER B--: Name der Bibliothek oder Bücherei BIBLIOTHEK---: Kategorie ERFASSER-----: Erfasser und Datum Erfassung anhand von Listen vom Ministerium für Bildung und Kultur. - Der/die Link(s) für das Herunterladen der Datensätze wird/werden dynamisch aus GetFeature Anfragen an einen WFS 1.1.0+ generiert
Organotin and especially butyltin compounds are used for a variety of applications, e.g. as biocides, stabilizers, catalysts and intermediates in chemical syntheses. Tributyltin (TBT) compounds exhibit the greatest toxicity of all organotins and have even been characterized as one of the most toxic groups of xenobiotics ever produced and deliberately introduced into the environment. TBT is not only used as an active biocidal compound in antifouling paints, which are designed to prevent marine and freshwater biota from settlement on ship hulls, harbour and offshore installations, but also as a biocide in wood preservatives, textiles, dispersion paints and agricultural pesticides. Additionally, it occurs as a by-product of mono- (MBT) and dibutyltin (DBT) compounds, which are used as UV stabilizer in many plastics and for other applications. Triphenyltin (TPT) compounds are also used as the active biocide in antifouling paints outside Europe and furthermore as an agricultural fungicide since the early 1960s to combat a range of fungal diseases in various crops, particularly potato blight, leaf spot and powdery mildew on sugar beet, peanuts and celery, other fungi on hop, brown rust on beans, grey moulds on onions, rice blast and coffee leaf rust. Although the use of TBT and TPT was regulated in many countries world-wide from restrictions for certain applications to a total ban, these compounds are still present in the environment. In the early 1970s the impact of TBT on nontarget organisms became apparent. Among the broad variety of malformations caused by TBT in aquatic animals, molluscs have been found to be an extremely sensitive group of invertebrates and no other pathological condition produced by TBT at relative low concentrations rivals that of the imposex phenomenon in prosobranch gastropods speaking in terms of sensitivity. TBT induces imposex in marine prosobranchs at concentrations as low as 0,5 ng TBT-Sn/L. Since 1993, for the littorinid snail Littorina littorea a second virilisation phenomenon, termed intersex, is known. In female specimens affected by intersex the pallial oviduct is transformed of towards a male morphology with a final supplanting of female organs by the corresponding male formations. Imposex and intersex are morphological alterations caused by a chronic exposure to ultra-trace concentrations of TBT. A biological effect monitoring offers the possibility to determine the degree of contamination with organotin compounds in the aquatic environment and especially in coastal waters without using any expensive analytical methods. Furthermore, the biological effect monitoring allows an assessment of the existing TBT pollution on the basis of biological effects. Such results are normally more relevant for the ecosystem than pure analytical data. usw.
Die Nukleation von Eispartikeln spielt eine wichtige Rolle bei der Wolken- und Niederschlagsbildung, mit Konsequenten für die atmosphärische Chemie, die Wolkenphysik und das Erdklima. Für eine Quantifizierung und Vorhersage des Einflusses von Wolken in Wettervorhersage- und Klimamodellen muss die Bildung von Eispartikeln daher in einer realistischen Art und Weise beschrieben werden. Einer der wichtigen Bildungsmechanismen ist dabei die heterogene Eisnukleation im Immersionsmodus, bei dem Eis an der Oberfläche eines in einem wässrigen Tröpfchen suspendierten Eiskeims - zum Beispiel eines Mineralstaub- Partikels - gebildet wird. Wir werden im Rahmen dieses Forschungsprojekts zahlreiche Gefrierexperimente im Immersionsmodus durchführen. So werden eine Reihe verschiedener, als Aerosolpartikel in der Atmosphäre vorkommende Materialien auf ihre Eisnukleationseigenschaften hin untersucht werden. Insbesondere sollen hier die Temperatur- und Zeitabhängigkeit der von diesen Materialien ausgelösten Eisnukleation quantifiziert werden. Dabei werden wir spezielles Augenmerk auf die systematische Untersuchung der von porösen Materialien ausgelösten Eisnukleation legen. Es sollen sowohl synthetische Materialien wie beispielsweise mesoporöse Silikate untersucht werden, als auch natürlich vorkommende Materialien wie etwa mikroporöse Zeolithe.
Magnetic resonance tomography (MRT) on microcosm soil cores (200 mm Ø) used for CeMiX, comprising naturally stacked subsoil down to 700 mm plus topsoil from CeFiT, will be implemented at a laterally partially open Split 1.5 T magnet, with intended final in-plane spatial resolution of 200 Micro m. Three-dimensional biopore distributions and dynamics of their formation within the cores will be determined non-invasively and compared to complementing CT analyses of SP 2. One major aim is a non-invasive differentiation of the biopores into earthworm- and root system-originating ones and currently air-, water-, root- and earthwormfilled ones, based on NMR relaxation parameters. Attempts will additionally be made to classify different wall coatings of the biopores with regard to their water affinity. Dynamics of water distribution within the microcosm core and its biopore structures, starting from initial values taken from CeFiT (SP 3), will be documented with an in-plane resolution of 5 mm, in parallel to measurements of root growth dynamics for calculation of biomass and root surface area. Special emphasis will be put on the role of the plant root system for a re-distribution of water/D2O (and solutes) between different soil layers. Finally we will attempt MRT-controlled sample collection from the microcosm cores, to get - together with our research unit partners of SPs 4-8 - repeated access to minimally invasively acquired data on nutrient and microorganism distributions in concert with non-invasively collected water and root distribution data as a basis for dynamic modelling of water and solute circuits in SP 10. Beside the microcosm cores, flat rhizotrons as used in SP 3 will be employed to enable measurements of root and shoot hydrostatic pressure profiles with pressure probes, in addition to MRT measurements. In this way water distributions and corresponding driving forces and growth dynamics will be measured altogether in a minimally invasive manner.
Sauropod dinosaurs represent one of the most important components of Mesozoic terrestrial vertebrate faunas, yet their early evolution and diversification in the Jurassic is still poorly understood. Furthermore, most of the pertinent data so far comes from Early and Middle Jurassic rocks in eastern Asia. The only abundant basal sauropod material reported from the Western Hemisphere so far comes from the Middle Jurassic Cañadón Asfalto Formation of Chubut province, Argentina, from where two species, Patagosaurus fariasi and Volkheimeria chubutensis, have been described. Especially the first of these taxa has figured prominently in basal sauropod phylogenies. However, recent research suggests that more sauropods are represented in the original material referred to this species, and intensive fieldwork in the rocks that have yielded these materials has resulted in the recovery of a wealth of new material. Thus, the objective of this project is a revision of the original materials of Patagosaurus as well as an incorporation of new materials. The alpha taxonomy of the sauropods from the Cañadón Asfalto Formation will be established, detailed osteological descriptions of the different taxa provided and their significance for our understanding of early sauropod evolution will be evaluated.
In freshwater sediments, iron oxidation is dominated by phototrophic and chemotrophic (aerobic and nitrate-reducing) Fe(ll)-oxidizing microorganisms. Although these biogeochemical processes have been investigated in detail in laboratory studies, not much is known about their spatial distribution, interactions (e.g. competition) amongst each other, as well as their response towards environmental perturbations (i.e. temperature, geochemical variations (nutrient, organic matter input)). This research proposal aims to investigate the activity, abundance and resource competition between different chemotrophic (aerobic and (autotrophic/mixotrophic) anaerobic nitrate-reducing) and phototrophic ironoxidizing microorganisms. In order to better understand the spatial distribution of nitrate-reducing iron oxidizing bacteria, microbial nitrate-producing and competing, nitrate-depletion processes will also be studied throughout the sedimentary redox gradient. In addition, the activity and abundance of the ironoxidizing processes will be quantified with (geo)microbiological, molecular and novel spectral imaging techniques. Using high resolution geochemical measurements (microsensors) we will characterize the environmental conditions these bacteria experience in order to determine the role of spatial and functional niche competition in microbial iron oxidation and the interconnection to the N-cycle. Iron mineral formation will be investigated as a function of the microbial spatial and temporal activity, depending on environmental perturbations. The proposed research study will strongly improve the understanding of iron cycling, the interconnection to the N-cycle, as well as interactions and competition between phototrophic and chemotrophic metabolisms in aquatic environments.
| Organisation | Count |
|---|---|
| Bund | 343 |
| Europa | 37 |
| Kommune | 32 |
| Land | 55 |
| Wissenschaft | 105 |
| Zivilgesellschaft | 154 |
| Type | Count |
|---|---|
| Daten und Messstellen | 1 |
| Förderprogramm | 324 |
| Repositorium | 3 |
| Text | 5 |
| unbekannt | 58 |
| License | Count |
|---|---|
| Geschlossen | 9 |
| Offen | 363 |
| Unbekannt | 19 |
| Language | Count |
|---|---|
| Deutsch | 267 |
| Englisch | 162 |
| Resource type | Count |
|---|---|
| Bild | 1 |
| Dokument | 4 |
| Keine | 306 |
| Unbekannt | 2 |
| Webdienst | 19 |
| Webseite | 70 |
| Topic | Count |
|---|---|
| Boden | 168 |
| Lebewesen und Lebensräume | 297 |
| Luft | 147 |
| Mensch und Umwelt | 391 |
| Wasser | 137 |
| Weitere | 385 |