Univ.-Prof. Dr. Andreas Richter
Soils are arguably the greatest frontier for ecological research. They are home to an almost inconceivable diversity of microbes, that together drive fundamental ecosystem processes, such as carbon, nitrogen and phosphorus cycling, essential for the functioning of the biosphere.
Microbes operate and interact at the micro-scale (both in space and time), but their activities become evident at the ecosystem to biosphere scale. Linking microbial activities to ecosystem functioning is thus one of the biggest challenges in current ecology, specifically as microbes constantly interact with other organisms, that are much larger and live much longer. We thus need new approaches to address this challenge, both conceptually and methodologically. Towards this end, my group is developing and constantly improving methods that allow estimating microbial gross processes to understand their controls and regulations. For example, have we pioneered stable isotope pool dilution methods to measure gross protein and cellulose depolymerisation rates in soil and litter, key processes in organic matter breakdown.
Heterotrophic microbes are responsible for the deconstruction and breakdown of all organic matter. At the same time, they become soil organic matter when they die and are thus responsible for the build-up of soil organic matter, the by far largest pool of organic carbon in terrestrial ecosystems. Understanding how microbes deconstruct and take up organic matter and build it into their own biomass is thus at the very basis of our understanding of how microbes control the global carbon cycle.
My group has recently critically reviewed and expanded the concept of microbial carbon use efficiency (CUE), i.e., the fraction of the organic carbon taken up by microorganisms, that is used for growth, and linked it to the theory of ecological stoichiometry. Since the methods usually used to estimate CUE in terrestrial ecosystems are based on 13C-labelled substrates and have been shown to inflate CUE, we have developed a novel approach to measure CUE based on incorporation of 18O-labelled water into DNA. Additionally, we have established a conceptional framework for a microbial nitrogen use efficiency (NUE) and have put forward a method that allows, for the first time, to measure NUE of microbial communities in soil and litter.
- Carbon use efficiency, growth and turnover of microbial communities
- Arctic soil carbon storage and the permafrost-climate feedback
- Microbial communities, SOM composition and the breakdown of organic matter
- Ecological stoichiometry and nitrogen and phosphorus cycling
- Effect of climate change and elevated CO2 on soil processes
- COUP - Constraining uncertainties in the permafrost-climate feedback
- INT5153 - Assessing the Impact of Climate Change on Land-Water-Ecosystem Quality in Polar and Mountainous Regions
- ClimGrass C - Grassland carbon dynamics in a changing climate
- Microbial Nitrogen Cycling - From Single Cells to Ecosystems: FWF Graduate Program
- EU-PolarNet - Connecting Science and Society
- CryoCARB - Advancing organic carbon estimates for cryoturbated soils
- MICDIF - Linking microbial diversity and functions across scales and ecosytems
- The Biogeochemistry of Tungsten (W) in the Plant-Soil Environment
- Time & Energy, Fundamental microbial mechanisms that determine methane dynamics in a warming arctic
COLLABORATION WITH OTHER INTERNATIONAL PROJECTS
- IMBALANCE P – Effects of phosphorus limitation on Life, Earth system and Society
We contribute to IMBALANCE P by analysing gross microbial nitrogen and phosphorus processes in soils along N/P gradients at two rainforest sites in French Guayana (Paracou and Nouragues). In addition we analyse microbial carbon and nitrogen use efficiencies and conduct laboratory incubation experiments with different nitrogen, phosphorus and carbon amendments to understand microbial limitations in those soils.
Investigated by: Andreas Richter, David Zezula
Cooperation partner: Josep Peñuelas, CREAF, Spain; Ivan Janssens, University of Antwerp, Belgium; Michael Obersteiner, IIASA, Austria
- FORHOT - Natural soil warming in natural grasslands in Iceland
We contribute several microbial measurements to the unique field experiment in FORHOT. Specifically, we ask the question whether the short-term (weeks to years; i.e., the duration of laboratory incubation experiments) and long-term (decades-century) temperature response of soil organic matter breakdown varies with regard to microbial carbon use efficiency, growth and turnover.
Investigated by: Andreas Richter, Tom Walker
Cooperation partner: Bjarni D. Sigurdsson, Agricultural University of Iceland
- The Jena Experiment – Exploring mechanisms underlying the relationship between biodiversity and ecosystem functioning
The Jena Experiment is studying biodiversity effects in experimental grassland communities. We contribute to this study by investigating biodiversity effects on microbial microbial carbon, nitrogen and phosphorus cycling. The overall aim of our project part is to elucidate the mechanisms behind the diversity effects on C, N and P cylcling, focusing on (i) microbial decomposition of organic carbon and nitrogen, (ii) element use efficiencies and (iii) microbial growth and turnover.
Investigated by: Andreas Richter, Judith Prommer
Cooperation partner: Wolfgang Weisser, University of Jena and Xavier Le Roux, INRA, Lyon, France
- CLIMAITE - Climate Change Effects on Biological Processes in Terrestrial Ecosystems
We contribute estimates of microbial nitrogen use efficiency and gross protein depolymerization rates to this experiment.
Investigated by: Andreas Richter, Birgit Wild
Cooperation partner: Per Ambus, University of Copenhagen
Zechmeister-Boltenstern, S., Keiblinger, K.M., Mooshammer, M., Peñuelas, J., Richter, A., Sardans, J., Wanek, W. (2015) The application of ecological stoichiometry to plant-microbial-soil organic matter transformations. Ecological Monographs 85: 135-155.
Wild, B., Schnecker, J., Knoltsch, J., Takriti, M., Mooshammer, M., Gentsch, N., Mikutta, R., Eloy Alves, R.J., Gittel, A., Lashchinskiy, N., Richter, A. (2015) Microbial nitrogen dynamics in organic and mineral soil horizons along a latitudinal transect in Western Siberia. Global Biogeochemical Cycles 29, 567–582.
Kaiser, C., Franklin, O., Dieckmann, U., Richter, A. (2014) Microbial community dynamics alleviate stoichiometric constraints during litter decay. Ecology Letters 17: 680–690.
Mooshammer, M., Wanek, W., Hämmerle, I., Fuchslueger. L., Hofhansl, F., Knoltsch, A., Schnecker, J., Takriti, M., Watzka, M., Wild, B., Keiblinger, K.M., Zechmeister-Boltenstern, S., Richter, A. (2014) Adjustment of microbial nitrogen use efficiency to carbon:nitrogen imbalances regulates soil nitrogen cycling. Nature Communications 5: 3694.
Mooshammer, M., Wanek, W., Zechmeister-Boltenstern, S., Richter, A. (2014) Stoichiometric imbalances between terrestrial decomposer communities and their resources: mechanisms and implications of microbial adaptations to their resources. Frontiers in Microbiology 5:22 (1-10).
Fuchslueger, L., Bahn, M., Fritz, K., Hasibeder, R., Richter, A. (2014) Experimental drought reduces the transfer of recently-fixed plant C to soil microbes and alters the bacterial community composition in a mountain meadow. New Phytologist 201: 916–927.
Sinsabaugh, R.L., Manzoni, S., Moorhead, D.L., Richter, A. (2013) Carbon use efficiency of microbial communities: Stoichiometry, methodology and modeling. Ecology Letters 16: 930–939.
Manzoni, S., Taylor, P., Richter, A., Porporato, A., Ågren, G. (2012) Environmental and stoichiometric controls on microbial carbon use efficiency in soils. New Phytologist 196: 79–91.
Mooshammer, M., Wanek, W., Schnecker, J., Wild, W., Leitner, S., Hofhansl, F., Blöchl, A., Hämmerle, I., Frank, A., Fuchslueger, L., Keiblinger K., Zechmeister-Boltenstern, S., Richter, A. (2012) Stoichiometric controls of nitrogen and phosphorus cycling in decomposing beech leaf litter. Ecology 93: 770–782.
Kaiser, C., Fuchslueger, L., Koranda, M., Gorfer, M., Stange, C.F., Kitzler, B., Rasche, F., Strauss, J., Sessitsch, A., Zechmeister-Boltenstern, S., Richter, A. (2011) Plants control the seasonal dynamic of microbial N cycling in a beech forest soil by belowground C allocation. Ecology 92: 1036–1051.
Wanek, W., Mooshammer, M., Blöchl, A., Hanreich, A., Keiblinger , K., Zechmeister-Boltenstern, S., Richter, A. (2010) Determination of gross rates of amino acid production and immobilization in decomposing leaf litter by a novel 15N isotope pool dilution technique. Soil Biology and Biochemistry 42: 1293-1302.
Kaiser, C., Meyer, H., Biasi, C., Rusalimova, O., Barsukov, P., Richter, A. (2007) Conservation of soil organic matter through cryoturbation in arctic soils in Siberia, Journal of Geophysical Research – Biogeosciences 112, G02017.
Our motto is "DIRT, SWEAT AND BEERS".
Information on open research positions can be found here.
If you are interested in joining our team with your own fellowship, please get in touch with Andreas for details.
There are several possibilities for PhD and PostDoc fellowships in Austria and Europe - if you are interested look at:
- uni:docs – PhD fellowship of the University of Vienna
- doc – PhD fellowships from the Austrian Academy of Science
- EU - Marie Curie fellowships for PostDocs
- FWF (Austrian Science Fund): Lise Meitner program for PostDocs from abroad
- FWF (Austrian Science Fund): Hertha Firnberg program for female PostDocs