Accurate knowledge of trace metal speciation is important for many reasons. First, it greatly affects bioavailability and hence uptake/toxicity in organisms. Second, the speciation determines the mobility of the trace metal in the environment. Our mission is to combine state-of-the-art characterization methods (such as synchrotron-based X-ray methods) with geochemical modelling and toxicity studies to arrive at improved understanding of trace metal behavior in soils. Vanadium will be taken as an example of a trace metal for which speciation is key to understanding both the chemical reactivity and biological uptake. Our V K-edge XANES studies show that vanadium added to soils is recovered mostly as vanadate(V) except in acid organic soils in which vanadyl(IV) predominates. The solubility of vanadate(V) therefore turns out to be of major importance for bioavailability, as shown by toxicity studies for barley. Another example is provided concerning how ZVI stabilization affects the speciation and solubility of arsenic and copper.
For phosphorus in agricultural soils, the speciation is rather complex and includes a variety of inorganic P forms as well as organic P. The use of P K-edge XANES spectroscopy has provided us with a tool that allows assessments of how the speciation changes in response to long-term fertilization as well as with depth within a soil profile. From these studies it is clear that adsorbed Al and Fe phases play a crucial role in determining the P dynamics over a time scale from years to decades; however, in some cases Ca-P phases may also form after heavy fertilization, at least temporarily. Moreover these studies show the dramatic changes that occur in P speciation during soil development, from a predominance of apatite to Al and Fe-associated P as well as organic P.
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invited by the group of Environmental Geochemistry
Datum | Vortragender | Titel |
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14.04.2016 | Prof. Otmar Urban Division of Impact Studies and Ecophysiological Analyses, CzechGlobe, Czech Academy of Sciences, Brno, CZ | Plant responses to climate change: impacts and adaptation [Abstract] |
21.04.2016 | Dr. Florian R.Storck DVGW-Technologiezentrum Wasser, Karlsruhe | Mikroplastik in Wasserressourcen – Anforderungen an die Analytik und erste Ergebnisse [Abstract] |
S 21, GEO-Gebäude 14:00-16:00 21.04.2016 | Dr. Jana Bürger Department Crop Health, Rostock University | Arable weeds under climate and land-use change – how ecological methods help agricultural researchers [Abstract] |
28.04.2016 | Dr. Michael Sander Environmental Chemistry, Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, Switzerland | Fate of biodegradable polyesters in agricultural soils - from enzymatic hydrolysis to microbial uptake and mineralization [Abstract] |
12.05.2016 | Prof. Jon Petter Gustafsson Soil and Groundwater Chemistry, KTH Stockholm / SLU Uppsala | Speciation and bioavailability of trace metals and phosphorus in soil systems [Abstract] |
02.06.2016 | Dr. Christine M. Klapeer Entwicklungssoziologie, Universität Bayreuth | Ist Natur politisch? Zum Zusammenhang von Naturkonzeptionen, Geschlechterverhältnissen und kolonialer Gewalt [Abstract] |
09.06.2016 | Dr. Julian Klaus Catchment and Eco-Hydrology Research Group, Luxembourg Institute of Science and Technology | Stable Isotopes in Hydrology: Progress in concepts and process understanding [Abstract] |
16.06.2016 | Freek T. Bakker (PhD) Biosystematics Group, Wageningen University, NL | Herbarium genomics, skimming & plastomics [Abstract] |
Mittwoch 22.06.2016 | Symposium zur Besetzung der W3-Professur Bodenphysik [Abstract] | |
13:00-14:00 23.06.2016 | PD Dr. Karsten Wesche Dept. of Botany, Senckenberg Museum of Natural History Görlitz | Climate controls override grazing effects under extreme conditions of Central Asia [Abstract] |
30.06.2016 | Prof. Dr. Andreas Lang Geomorphology and Environmental Systems, University of Salzburg, AT | The Anthropocene - is there a case for a new geological epoch? [Abstract] |
21.07.2016 | Dr. Marie Spohn Soil Biogeochemistry, Soil Ecology, BayCEER, University of Bayreuth | Biogenic Weathering [Abstract] |
BayCEER-Kolloquium: |
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Do. 28.01.2021 aktuell BayCEER Mitgliederversammlung |
Do. 15.04.2021 - folgt - |
Do. 22.04.2021 - folgt - |
Do. 29.04.2021 - folgt - |
Ökologisch-Botanischer Garten: |
Do. 11.02.2021 Online-Veranstaltung: Mit dem Kanu durch den Regenwald. Eine Expedition in die Überschwemmungswälder Süd-Venezuelas |
13.01.2020 Why Science Communication? |
24.05.2019 Stoichiometric controls of C and N cycling |
07.05.2019 Flying halfway across the globe to dig in the dirt – a research stay in Bloomington, USA |
16.04.2019 Picky carnivorous plants? |