A5001536488- Marine and coastal ecosystems
- Microbial Community Ecology and Physiology
- Aquatic Ecosystems and Phytoplankton Dynamics
- Geology and Paleoclimatology Research
- Protist diversity and phylogeny
- Polar Research and Ecology
- Cryospheric studies and observations
- Isotope Analysis in Ecology
- Soil and Water Nutrient Dynamics
- Groundwater and Isotope Geochemistry
- Atmospheric chemistry and aerosols
- Wastewater Treatment and Nitrogen Removal
- Climate change and permafrost
- Aquatic Invertebrate Ecology and Behavior
- Hydrology and Watershed Management Studies
- Diatoms and Algae Research
- Toxic Organic Pollutants Impact
- Heavy metals in environment
- Genomics and Phylogenetic Studies
- Air Quality and Health Impacts
- Integrated Water Resources Management
- Fish Ecology and Management Studies
- Water Quality and Pollution Assessment
- Ecology, Conservation, and Geographical Studies
- Atmospheric and Environmental Gas Dynamics
Universität Innsbruck
2011-2023
Eurac Research
2017-2023
Stellenbosch University
2008
Institut für ökologische Wirtschaftsforschung
2008
Bundesministerium für Land- und Forstwirtschaft, Umwelt und Wasserwirtschaft
2008
Universitat de Barcelona
2002
Czech Academy of Sciences
1996-1999
Hydrobiological Institute
1999
University of Konstanz
1997
Institute of Hydrobiology, Biology Centre, Academy of Sciences of the Czech Republic
1996
ABSTRACT We applied transmission electron microscopy and densitometric image analysis to measure the cell volume ( V ) dry weight (DW) of single bacterial cells. The system was DW Escherichia coli DSM 613 at different growth phases natural assemblages two lakes, Piburger See Gossenköllesee. found a functional allometric relationship between (in femtograms) cubic micrometers) bacteria (DW = 435 · 0.86 ); i.e., smaller had higher ratio than larger measured E. cells ranged from 83 1,172 fg,...
Abstract Cryoconite holes, which can cover 0.1–10% of the surface area glaciers, are small, water‐filled depressions (typically <1 m in diameter and usually <0.5 deep) that form on glaciers when solar‐heated inorganic organic debris melts into ice. Recent studies show cryoconites colonized by a diverse range microorganisms, including viruses, bacteria algae. Whether microbial communities actively influencing biogeochemical cycles or just present dormant state has been matter debate for...
It is well known that the atmosphere a conveyor of microorganisms, and bacteria can act as ice or cloud condensation nuclei, but clouds have not been considered site where organisms live reproduce. Here we show in droplets collected at high altitudes are actively growing reproducing temperatures below 0°C. Since ∼60% earth surface covered by clouds, water should be microbial habitat.
ABSTRACT The seasonal variations in community structure and cell morphology of pelagic procaryotes from a high mountain lake (Gossenköllesee, Austria) were studied by situ hybridization with rRNA-targeted fluorescently labeled oligonucleotide probes (FISH) image-analyzed microscopy. Compositional changes biomass fluctuations within the assemblage observed both summer beneath winter ice cover are discussed context physicochemical biotic parameters. Proteobacteria beta subclass...
High‐altitude lakes are exposed to high fluence rates of solar ultraviolet radiation (UVR; 29–400 nm) and contain low concentrations dissolved organic carbon (DOC). While in most lowland lakes, DOC can be used predict UV transparency with sufficient accuracy, current models fail estimate UVR clear alpine lakes. In these phytoplankton may contribute significantly the attenuation either as particles or a source chromophoric matter (CDOM) distinctive properties. We investigated series 26 Alps...
The study of fish concentrations and sediment inventories in 19 European high mountain lakes (40−67°N) shows that a fraction organochlorine compounds (OCs), the less volatile (LVC; subcooled liquid vapor pressure ≤ 10-2.5 Pa), are trapped higher locations. This general trend is not significantly influenced by possible local sources. Compound distribution related to average air temperatures. phase-change pseudoenthalpies calculated from closely match summed theoretical volatilization...
The bacterial community structure in the winter cover and pelagic zone of a high mountain lake was analyzed by situ hybridization with fluorescently labeled rRNA-targeted oligonucleotide probes. Cells fixed on membrane filters were hybridized probe specific for domain Bacteria as well probes alpha, beta, gamma subclasses class Proteobacteria Cytophaga-Flavobacterium group. fraction bacteria detectable after EUB ranged from 40 to 81% 4(prm1),6-diamidino-2-phenylindole (DAPI) counts....
In late summer 1993 an intensive study was carried out on protozoan grazing in the epilimnion and metalimnion of eutrophic Rímov Reservoir south Bohemia. On average, ∼ 70% bacterial production consumed by heterotrophic flagellates 20% ciliates. Ciliate numbers increased from 5 to 70 cells ml −1 over 5‐week period. Ciliates <30 µ m size were numerically dominant both layers included Halteria grandinella Strobilidium hexakinetum (Oligotrichida), Cyrtolophosis mucicola (Cyrtolophosida),...
In a two-stage continuous-flow system, we studied the impacts of different protozoan feeding modes on morphology and taxonomic structure mixed bacterial consortia, which were utilizing organic carbon released by pure culture Rhodomonas sp. grown inorganic medium in first stage system. Two three second stages operated parallel inoculated bacterivorous flagellate, Bodo saltans, an algivorous ciliate, Urotricha furcata, respectively. The third vessel served as control. two experiments, where...
Abstract. For the past 200 years, field of aerobiology has explored abundance, diversity, survival and transport micro-organisms in atmosphere. Micro-organisms have been as passive severely stressed riders atmospheric systems. Recently, an interest active roles these emerged along with proposals that atmosphere is a global biome for microbial metabolic activity perhaps even multiplication. As part series papers on sources, distribution processes biological particles atmosphere, here we...
ABSTRACT We used in situ hybridization with fluorescently labeled rRNA-targeted oligonucleotide probes concurrently measurements of bacterial carbon production, biomass, and extracellular polymeric substances (EPS) to describe the community sediments along a glacial stream. The abundance sediment-associated Archaea , as detected ARCH915 probe, decreased downstream glacier snout, major storm increased their relative by factor 5.5 7.9. Bacteria Cytophaga-Flavobacterium group were also sixfold...
We studied predator-induced changes within a slowly growing mixed microbial assemblage that was sustained by algal exudates in continuous cultivation system. In situ hybridization with fluorescent monolabeled oligonucleotide probes used for tentative community analysis. This method also allowed us to quantify the proportions of predators ingested bacteria different taxonomic groups. addition, we determined grazing rates on fluorescently labelled prey. Bacteria belonging alpha and beta...
We studied the effect of solar radiation on incorporation [(sup3)H]thymidine ([(sup3)H]TdR) and [(sup14)C]leucine ([(sup14)C]Leu) by bacterioplankton in a high mountain lake northern Adriatic Sea. After short-term exposure (3 to 4 h) natural bacterial assemblages sunlight just beneath surface, rates [(sup3)H]TdR [(sup14)C]Leu were reduced at both sites up (symbl)70% compared those for dark control. Within UV (290 400 nm), inhibition was caused exclusively UV-A (320 nm). However,...
Bulk deposition samples were taken near three mountain lakes located in the Pyrenees (Estany Redó), Alps (Gossenköllesee), and Caledonian Mountains (Øvre Neådalsvatn) for evaluation of atmospheric load organochlorine compounds (OC), namely, polychlorobiphenyls (PCBs), hexachlorocyclohexanes (HCHs), hexachlorobenzene (HCB), endosulfans, remote European high areas. The present use agriculture, endosulfans γ-HCH, exhibit large differences mean fluxes between sites. They occur amounts Estany...
ABSTRACT We investigated whether individual populations of freshwater bacteria in mixed experimental communities may exhibit specific responses to the presence different bacterivorous protists. In two successive experiments, a two-stage continuous cultivation system was inoculated with nonaxenic batch cultures cryptophyte Cryptomonas sp. Algal exudates provided sole source organic carbon for growth accompanying microflora. The dynamics several 16S rRNA-defined bacterial were followed...
AME Aquatic Microbial Ecology Contact the journal Facebook Twitter RSS Mailing List Subscribe to our mailing list via Mailchimp HomeLatest VolumeAbout JournalEditorsSpecials 10:255-263 (1996) - doi:10.3354/ame010255 Top-down effects on size-biomass distribution of a freshwater bacterioplankton community Pernthaler J, Sattler B, Simek K, Schwarzenbacher A, Psenner R Protistan size-selective grazing aquatic bacteria has frequently been demonstrated in laboratory, but its postulated size...
Over the past two decades, we have observed a substantial rise in solute concentration at remote high mountain lakes catchments of metamorphic rocks European Alps. At Rasass See, electrical conductivity increased 18-fold. Unexpectedly nickel concentrations which exceeded limit drinking water by more than 1 order magnitude, cannot be related to catchment geology. We attribute these changes lake quality release from ice an active rock glacier as response climate warming. Similar processes...