• Global Warming:

    the threat of a permafrost Carbon – climate feedback

  • We develop and improve

    stable isotopes techniques for ecological applications

  • Plants, fungi and bacteria interact

    at the root-soil interface

  • Probing the future:

    Climate Change experiments

  • Soil is fundamental to human life

  • Tropical rainforests

    hold the key to global net primary productivity

TER News

Latest publications

Phytosiderophore-induced mobilization and uptake of Cd, Cu, Fe, Ni, Pb and Zn by wheat plants grown on metal-enriched soils

We investigated to which extent phytosiderophores (PS), released by grasses for the acquisition of iron, solubilize other metals in contaminated soils, and how this affects metal mobilization and uptake in wheat plants. A plant-based bioassay (‘RHIZOtest’) and batch extraction scheme were carried out for assessing metal mobilisation in soil, PS exudation and metal accumulation in wheat. Increased PS exudation was observed in Fe-deficient wheat, leading to enhanced Zn, Cu, Mn and Ni concentrations in wheat shoots on some soils. In contrast, plant Cd and Pb concentrations were not affected. Likewise, in the batch experiment, strongly increased extractable Cu, Ni and Zn concentrations were observed, in particular when 100 or 1000 μM PS were added. Our results suggest that Fe deficiency can enhance the accumulation of some metals in shoots of grass species. Although our results indicate that the risk of enhanced accumulation of Cd and Pb in Fe deficient wheat shoots is rather small, further experiments conducted on soil for the complete vegetation period would be needed to confirm this observation.

Puschenreiter M, Gruber B, Wenzel WW, Schindlegger Y, Hann S, Spangl B, Schenkeveld WDC, Kraemer SM, Oburger E
2017 - Environmental and Experimental Botany, 138: 67-76

Microbial utilization of mineral-associated nitrogen in soils

In soils, a large portion of organic nitrogen (ON) is associated with minerals and thus, possibly stabilized against biological decay. We therefore tested if mineral-associated N is an important N source for soil microorganisms, and which soil parameters control its bioavailability. Microcosm experiments with mineral-associated organic matter, obtained as heavy fraction (HF) via density fractionation, and bulk soil from mineral topsoil of the Franz Josef chronosequence were conducted for 125 days. We examined the effects of O2 status, soil age (differences in mineralogical properties), as well as cellulose and phosphate additions on the turnover of mineral-associated N. Using a combination of activity measurements and quantitative PCR, microbial N transformation rates and abundances of N-related functional genes (amoAnarGchiA) were determined. Similar or higher values for microbial N cycling rates and N-related functional abundances in the HF compared to bulk soil indicated that mineral-associated N provides an important bioavailable N source for soil microorganism. The turnover of mineral-associated N was mainly controlled by the O2 status. Besides, soil mineralogical properties significantly affected microbial N cycling and related gene abundances with the effect depending on the N substrate type (ON, NH4+ or NO3). In contrast, cellulose or phosphate addition hardly enhanced microbial utilization of mineral-associated N. The results of our microcosm study indicate that mineral-associated N is highly bioavailable in mineral topsoils, but effects of the mineral phase differ between N cycling processes.

Turner S, Meyer-Stüve S, Schippers A, Guggenberger G, Schaarschmidt F, Wild B, Richter A, Dohrmann R, Mikutta R
2017 - Soil Biology and Biochemistry, 104: 185-196

Stable isotope signatures reflect dietary diversity in European forest moths

Background: Information on larval diet of many holometabolous insects remains incomplete. Carbon (C) and nitrogen (N) stable isotope analysis in adult wing tissue can provide an efficient tool to infer such trophic relationships. The present study examines whether moth feeding guild affiliations taken from literature are reflected in isotopic signatures. Results: Non-metric multidimensional scaling and permutational analysis of variance indicate that centroids of dietary groups differ significantly. In particular, species whose larvae feed on mosses or aquatic plants deviated from those that consumed vascular land plants. Moth δ15N signatures spanned a broader range, and were less dependent on species identity than δ13C values. Comparison between moth samples and ostensible food sources revealed heterogeneity in the lichenivorous guild, indicating only Lithosia quadra as an obligate lichen feeder. Among root-feeding Agrotis segetum, some specimens appear to have developed on crop plants in forest-adjacent farm land. Reed-feeding stem-borers may partially rely on intermediary trophic levels such as fungal or bacterial growth. Conclusion: Diagnostic partitioning of moth dietary guilds based on isotopic signatures alone could not be achieved, but hypotheses on trophic relationships based on often vague literature records could be assessed with high resolution. Hence, the approach is well suited for basic categorization of moths where diet is unknown or notoriously difficult to observe (i.e. Microlepidoptera, lichen-feeders). Keywords: δ13C, δ15N, Larval diet, Trophic position Abbreviations: C, Chemical symbol for carbon; IAEA-CH-6, Reference standard for 13C/12C ratios derived from sucrose and provided by the international atomic energy agency (IAEA); IAEA-CH-7, Reference standard for 13C/12C ratios derived from polyethylene and provided by the international atomic energy agency (IAEA); IAEA-N-1, Reference standard for 15N/ 14N ratios derived from ammonium sulfate and provided by the international atomic energy agency (IAEA); IAEA-N- 2, Reference standard for 15N/14N ratios derived from ammonium sulfate and provided by the international atomic energy agency (IAEA); IAEA-NO-3, Reference standard for 15N/14N ratios derived from potassium nitrate and provided by the international atomic energy agency (IAEA); MMDS, Metric multi-dimensional scaling; N, Chemical symbol for nitrogen; NMDS, Non-metric multi-dimensional scaling; SD, Standard deviation; TLE, Trophic level enrichment; δ 13C, Shift in the 13C/12C ratio of the sample relative to the reference standard (i.e. Pee Dee Belemnite); δ 15N, Shift in the 15N/14N ratio of the sample relative to the reference standard (i.e. atmospheric nitrogen)

Adams MO, Seifert CL, Lehner L, Truxa C, Wanek W, Fiedler K
2016 - Frontiers in Zoology, 13: 1-10

Lecture series

Microbial function in relation to plant productivity and root exudation in contrasting tundra communities

Konstantin GAVAZOV
Climate Impacts Research Centre (CIRC), Umeå University, Abisko, Sweden
20.03.2017
14:00 h
Seminar Room 'Konferenzraum Ökologie' UZA 1, Althanstr. 14, 1090 Wien

LC-MS Approaches in Metabolomics

Gunda Köllensperger, Prof.
University of Vienna, Department of Analytical Chemistry
12.01.2017
11:15 h
Seminar Room Microbial Ecology, UZA 1, room no 2.309

Arbuscular mycorrhizas and organic nitrogen in soil – and the other microbes involved

Jan Jasna
Institute of Microbiology, Academy of Sciences of the Czech Republic
11.10.2016
16:00 h
Friedrich-Becke Seminar Room, UZA 2 (Geozentrum), Althanstr. 14, 1090 Wien