BERG focuses on microbial biofilms and their implications for ecosystem functioning and biogeochemistry in streams and rivers. Microbial biofilms dominate microbial life density in numerous freshwater ecosystems, and particularly in headwaters — the smallest but most abundant streams in fluvial networks. We are particularly interested in the coupled physical, chemical and biological processes that link biofilms to ecosystem processes and large-scale carbon and nutrient fluxes. Only recently has the relevance of freshwaters for global carbon fluxes been recognized. We hope that our research will expand our understanding, why ecosystems that contribute only marginally to the surface area of our planet, disproportionately contribute to the carbon fluxes that govern the biogeochemistry of our planet.
Areas of interest:
Stream ecosystem ecology, biogeochemistry, biofilm ecology, carbon fluxes, hydrodynamics and geomorphology, ecological theory, science
Battin, T.J., Luyssaert, S., Kaplan, L.A., Aufdenkampe, A.K., Richter, A. and Tranvik., L.J. (2009): The boundless carbon cycle. Nature Geoscience 2 (598 – 601).
Battin, T.J., Kaplan, L.A., Findlay, S., Hopkinson, C.S., Marti, E., Packman, A.I., Newbold, J.D. and Sabater, F. (2008): Biophysical controls on organic carbon fluxes in fluvial networks.Nature Geosciencedoi:10.1038/ngeo101.
Biogeochemical functions: research and management at Mmultiple scales research group (BIOFRAMES), group leader Hein Thomas
Our team investigates nutrient cycling and carbon dynamics in surface water dominated wetlands, their role in riverine landscapes and their importance providing ecosystem services. Riverine wetlands and riparian zones are ecosystems of strategic importance for matter cycling and biodiversity and at the same time intensely used and altered by humans. In context with these modified systems we are particularly interested in the interaction between hydromorphology, biogeochemical processes and selected aspects of biodiversity as well as the link between research and application in sustainable ecosystem management. The purpose of our research is to determine how changing conditions at the large scale (climate change) and the local scale (pollution, hydromorphological alterations) interact with the coupling of structure and function and explicitly, the interaction with restoration activities and ecosystem management. Thus, the scope of our research ranges from the community and habitat level to the ecosystem level and integrates field studies with experimental approaches. The research activity in BioFrames is devoted to establishing mechanistic models for primary production and the coupling with nutrient cycling in the water column, at the sediment/water and aquatic/terrestrial interface in wetlands and river systems.
Areas of interest:
Biogeochemistry, restoration ecology and the resilience of ecosystems, tools and models for multi criteria analysis for sustainable ecosystem management, stable isotope research and application
Bondar-Kunze, E., Preiner, S., Schiemer, F., Weigelhofer, G., Hein, T. (2009): Effect of enhanced water exchange on ecosystem functions in backwaters of an urban floodplain. Aquatic Sciences 71(4): 437-447.
Weigelhofer, G., Fuchsberger, J., Teufl, B., Welti, N., Hein, T. (2011): Effects of reparian forest buffers on in-stream nutrient retention in agricultural catchments. Journal of Environmental Quality, 37:1507-1514.
LIPTOX investigates processes that govern organic matter pathways to organisms in aquatic ecosystems. Our research ranges from molecular to community levels, with the goal of integrating knowledge from nutritional ecology and ecotoxicology at various trophic scales. In particular, we focus on lipids and their fatty acids as especially some polyunsaturated fatty acids are fundamental to somatic development, reproduction, and survival of aquatic organisms. Such clearly favorable effects are opposite to the mostly negative effects of stressors (such as contaminants, species invasions, temperature, etc.) in aquatic food webs. These concurrent effects within aquatic food webs are poorly understood and encourage us to investigate linkages between dietary uptake, bioconversion, and retention of lipids and contaminants in organisms of aquatic food webs. Our goal is to improve knowledge of the structure and function of aquatic food webs, and to develop tools for better management of aquatic ecosystems in the face of future change.
Areas of interest:
Food web ecology, aquatic lipid biochemistry, ecotoxicology, physiological stressors, biomarkers (allochthonous and autochthonous)
Brett, M. T., Kainz. M., Taipale, S., and Seshan, H. (2009): Phytoplankton, not allochthonous carbon, sustains herbivorous zooplankton production. PNAS 106: 21197-21201.
Arts, M. T., Brett, M. T., and Kainz, M., eds. (2009): Lipids in Aquatic Ecosystems. Springer Verlag, New York. 377 p.