Life Science II 191
Research Specialties: Microbial Ecology, Marine and Freshwater Microbiology, Biogeochemistry. Emphasizing the importance of microorganisms in both pristine and polluted environments, our research attends to the diverse interactions of bacteria and archaea with nitrogen, sulfur, carbon and arsenic compounds in aquatic ecosystems.
PhD, 2000, University of Bremen, Germany
Within a broad range of scientific interest, my research is focused on interactions between microorganisms (Archaea, Bacteria, microalgae) and their physical, geochemical and biological environment. Previous, ongoing and potential future investigations deal with the role of microbial species or groups in biogeochemical processes and reversely, effects of physical and geochemical factors on community structure, physiological potential and metabolic activities. In addition to these analytical studies, my goals include experimental studies of microbial responses - from cellular to community level - to stressors, environmental fluctuation, natural and anthropogenic disturbances.
Nitrifying bacteria in floodplain wetlands. Large amounts of nutrients from agriculture and sewage have impaired water quality in the Mississippi River Basin and contributed to seasonal anoxia in the Gulf of Mexico. Floodplain wetlands and their microbial communities play an important role in mitigating the nutrient load of river water. In the marshes and swamps of three river systems (Illinois, middle Mississippi and Cache River), we investigate relations between concentrations of dissolved nitrogen compounds and the distribution and abundance of bacterial guilds that catalyze oxidative processes in the N cycle.
Sulfur cycling bacteria in flooded strip mines. Major parts of Illinois are underlain by coal bearing strata, that have been mined extensively for the past 200 years. With the S-rich coal, significant amounts of sulfides reach the surface and become oxidized to form acid mine drainage, contaminating soil and groundwater. Despite reclamation and restoration efforts in abandoned mining areas, local streams and lakes retain higher S concentrations than typical freshwater. On the example of a flooded strip mine in southern Illinois, we examine microbial communities in S-enriched freshwater. The distribution, diversity and abundance of phototrophic and chemotrophic bacterial guilds that catalyze processes in the S cycle is determined in relation to concentrations of dissolved S compounds.
Nitrogen cycling archaea and bacteria in temperate lakes. Agricultural runoff, communal and industrial wastewaters are recognized sources of excessive nutrient (N, P) input into streams and lakes. The eutrophic Central Basin of Lake Erie and several mesotrophic dimictic lakes in southern Illinois are sites of our research into environmental effects on microorganisms that, in turn, affect the N budget of freshwater ecosystems. My particular interest is in the role of archaea in the N cycle of temperate aquatic systems.
Nitrogen cycling archaea and bacteria in coral reef sediments. Tropical coral reef ecosystems tend to be nutrient-limited, and sustaining their high productivity may depend on efficient local recycling of nutrients by benthic microbial communities. Permeable reef sediments are sites of dynamic hydrology, variable and heterogeneous geochemistry and diverse microhabitats. Sandy reef sediments in Hawaii and Florida have been my sandbox for exploring the microbiota that engage in the degradation of organic matter and recycling of nutrients. More specific research is focused on the microbial guilds that catalyze aerobic and anaerobic processes in the N cycle. Their distribution, diversity, abundance and activity is measured in relation to geochemical resources and conditions as well as geographic distance.
Ecophysiology of arsenic metabolizing bacteria. High arsenic concentrations in waters, sediments and soils often result from hydrothermal, mining or smelting activities. Arsenic-contaminated crops and drinking water compromise the health of an estimated 40 million people world-wide. Microorganisms that can enhance the oxidation, reduction, methylation, dissolution and precipitation of As compounds may hold clues to mitigation strategies. We have isolated a novel bacterium from an arsenic-rich hydrothermal environment and are characterizing its ecological niche.
Articles in Professional Journals
- Rusch, A. and Gaidos, E., 2013. Nitrogen-cycling bacteria and archaea in the carbonate sediment of a coral reef. Geobiology, 11, 472-484. DOI link
- Rusch, A., 2013. Molecular tools for the detection of nitrogen cycling Archaea. Archaea, 2013, article 676450. DOI link
- Gaidos, E., Rusch, A. and Ilardo, M., 2011. Ribosomal tag pyrosequencing of DNA and RNA from benthic coral reef microbiota: community spatial structure, rare members and nitrogen-cycling guilds. Environmental Microbiology, 13, 1138-1152. PubMed link
- Rusch, A., Hannides, A.K. and Gaidos, E., 2009. Diverse communities of active Bacteria and Archaea along oxygen gradients in coral reef sediments. Coral Reefs, 28, 15-26. DOI link
- Gaidos, E., Marteinsson, V., Thorsteinsson, T., Jóhannesson, T., Rúnarsson, Á.R., Stefansson, A., Glazer, B., Lanoil, B., Skidmore, M., Han, S., Miller, M., Rusch, A. and Foo, W., 2009. An oligarchic microbial assemblage in the anoxic bottom waters of a volcanic subglacial lake. The ISME Journal, 3, 486-497. DOI link
- Rusch, A. and Amend, J.P., 2008. Functional characterization of the microbial community in geothermally heated marine sediments. Microbial Ecology, 55, 723-736. DOI link
- Rusch, A., Huettel, M., Wild, C. and Reimers, C.E., 2006. Benthic oxygen consumption and organic matter turnover in organic-poor, permeable shelf sands. Aquatic Geochemistry, 12, 1-19. DOI link
- Rusch, A., Walpersdorf, E., de Beer, D., Gurrieri, S. and Amend, J.P., 2005. Microbial communities near the oxic/anoxic interface in the hydrothermal system of Vulcano Island, Italy. Chemical Geology, 224, 169-182. DOI link
- Rusch, A. and Amend, J.P., 2004. Order-specific 16S rRNA-targeted oligonucleotide probes for (hyper)thermophilic archaea and bacteria. Extremophiles, 8, 357-366. DOI link
- Rusch, A. and Amend, J.P. 2004. Microbes in geothermally heated marine sediments - community structure and metabolism. Geochimica et Cosmochimica Acta, 68, A404.
- Reimers, C.E., Stecher, H.A. III, Taghon, G.L., Fuller, C.M., Huettel, M., Rusch, A., Ryckelynck, N. and Wild, C., 2004. In situ measurements of advective solute transport in permeable shelf sands. Continental Shelf Research, 24, 183-201. DOI link
- Rusch, A., Huettel, M., Reimers, C.E., Taghon, G.L. and Fuller, C.M., 2003. Activity and distribution of bacterial populations in Middle Atlantic Bight shelf sands. FEMS Microbiology Ecology, 44, 89-100. DOI link
- Rusch, A., Forster, S. and Huettel, M., 2001. Bacteria, diatoms and detritus in an intertidal sandflat subject to advective transport across the water-sediment interface. Biogeochemistry, 55, 1-27. DOI link
- Rusch, A., Huettel, M. and Forster, S., 2000. Particulate organic matter in permeable marine sands - dynamics in time and depth. Estuarine, Coastal and Shelf Science, 51, 399-414. DOI link
- Huettel, M. and Rusch, A., 2000. Transport and degradation of phytoplankton in permeable sediment. Limnology and Oceanography, 45, 534-549. DOI link
- Rusch, A. and Huettel, M., 2000. Advective particle transport into permeable sediments - evidence from experiments in an intertidal sandflat. Limnology and Oceanography, 45, 525-533. DOI link
- Rusch, A., Töpken, H., Böttcher, M.E. and Höpner, T., 1998. Recovery from black spots: results of a loading experiment in the Wadden Sea. Journal of Sea Research, 40, 205-219. DOI link
- Böttcher, M.E., Rusch, A., Höpner, T. and Brumsack. H.-J., 1998. Stable sulfur isotope effects related to local intense sulfate reduction in a tidal sandflat (Southern North Sea): results from loading experiments. Isotopes in Environmental and Health Studies, 34, 109-129. DOI link
Chapters in Professional Books
- Rusch, A., 2014. Archaea. In: Kennish, M.J. (ed.) Encyclopedia of Estuaries. Springer, Heidelberg; in press.
- Rusch, A., 2014. Autotrophic. In: Kennish, M.J. (ed.) Encyclopedia of Estuaries. Springer, Heidelberg; in press.
- Rusch, A., 2014. Heterotrophic. In: Kennish, M.J. (ed.) Encyclopedia of Estuaries. Springer, Heidelberg; in press.
- Rusch, A., 2014. Mutualism. In: Kennish, M.J. (ed.) Encyclopedia of Estuaries. Springer, Heidelberg; in press.
- Rusch, A., 2014. Symbiosis. In: Kennish, M.J. (ed.) Encyclopedia of Estuaries. Springer, Heidelberg; in review.