nitrogen cycle; stable isotopes; denitrification; biomarkers; methylotrophic bacteria; organic matter degradation; soil carbon; symbiosis; mycorrhiza
Wenk Christine B., Blees Jan, Zopfi Jakob, Veronesi Mauro, Bourbonnais Annie, Schubert Carsten J., Niemann Helge, Lehmann Moritz F. (2013), Anaerobic ammonium oxidation (anammox) bacteria and sulfide-dependent denitrifiers coexist in the water column of a meromictic south-alpine lake, in
LIMNOLOGY AND OCEANOGRAPHY, 58(1), 1-12.
Henneberger Ruth, Chiri Eleonora, Blees Jan, Niemann Helge, Lehmann Moritz F., Schroth Martin H. (2013), Field-scale labelling and activity quantification of methane-oxidizing bacteria in a landfill-cover soil, in
FEMS MICROBIOLOGY ECOLOGY, 83(2), 392-401.
Walder Florian, Niemann Helge, Lehmann Moritz F., Boller Thomas, Wiemken Andres, Courty Pierre-Emmanuel (2013), Tracking the carbon source of arbuscular mycorrhizal fungi colonizing C-3 and C-4 plants using carbon isotope ratios (delta C-13), in
SOIL BIOLOGY & BIOCHEMISTRY, 58, 341-344.
Niemann H., Stadnitskaia A., Wirth S. B., Gilli A., Anselmetti F. S., Damste J. S. Sinninghe, Schouten S., Hopmans E. C., Lehmann M. F. (2012), Bacterial GDGTs in Holocene sediments and catchment soils of a high Alpine lake: application of the MBT/CBT-paleothermometer, in
CLIMATE OF THE PAST, 8(3), 889-906.
Walder Florian, Niemann Helge, Natarajan Mathimaran, Lehmann Moritz F., Boller Thomas, Wiemken Andres (2012), Mycorrhizal Networks: Common Goods of Plants Shared under Unequal Terms of Trade, in
PLANT PHYSIOLOGY, 159(2), 789-789.
Bourbonnais Annie, Lehmann Moritz F., Butterfield David A., Juniper S. Kim (2012), Subseafloor nitrogen transformations in diffuse hydrothermal vent fluids of the Juan de Fuca Ridge evidenced by the isotopic composition of nitrate and ammonium, in
GEOCHEMISTRY GEOPHYSICS GEOSYSTEMS, 13, 1.
Funding is requested to further develop an environmental laboratory for aquatic and terrestrial biogeochemistry at the Institute for Environmental Geoscience (IEG), University of Basel. The requested infrastructure will support research that will make use of molecular-level characterization and (compound-specific) isotope ratio determination methods to assess a wide spectrum of biogeochemical transformations in the natural environment and in the laboratory, and to study sources and the fate of organic compounds in aquatic and soil systems along four main research themes/objectives: I) using lipid biomarker approaches to study microbial communities in various marine and freshwater environments, II) characterizing organic matter (OM) components in lacustrine sediments as well as in soils, and identifying the mechanisms responsible for the longer-term sequestration and degradation of organic carbon and the emission of greenhouse gases, III) understanding the metabolic pathways of C and N during the symbiosis between microorganisms and plants, and IV) generating data sets for the isotopic composition of nitrate (NO3-) and other N species in various aquatic systems in order to characterise the controls on isotope fractionation of specific N cycle reactions. The spectrum of investigated ecosystems will range from Swiss soil and groundwater systems and lakes to hydrothermal vent and cold seep systems in the deep ocean. The spatial scale of the planned research extends from enzyme biogeochemistry to ocean-scale circulation, with implications for the understanding of intracellular metabolic processes in plants and microorganisms, and the regional and global C and N cycles. The requested infrastructure includes the following instruments:•Gas Chromatograph coupled to a quadrupole mass spectrometer (MS) with two detectors (FID and MS) for organic compound recognition. Through the GC-C III interface, the GC will be coupled to the IRMS for isotope measurements on single target molecules.•Gas source stable isotope ratio mass spectrometer (IRMS) with 5-collector configuration, Gasbench-II Interface, accessories for 18O and H/D analysis in GC eluates, and autosampler for high-precision isotope ratio determination.A GC/MS system does not yet exist at the IEG, and an existing IRMS is already operating at full capacity. N isotope measurements in dissolved nitrogen species, biomarker analyses and compound-specific stable isotope ratio determination (natural abundance and labeled) will represent main thrusts of envisioned research activities, making a new GC-MS and a second IRMS system a necessity. The requested infrastructure will partially be coupled to, and thus enhance, already existing instruments, optimizing resources and space allocation. It will benefit from human resources and the analytical expertise already present at the IEG, assuring successful implementation of analytical methods and maintenance of instruments. The planned expansion of the IEG facility will permit the addition of novel aspects to the research conducted in Switzerland. It will offer exciting new analytical possibilities and permit the analysis of a wide range of environmental materials, with a plethora of potential applications and a large group of potential users.