Field samples

Autofluorescence based flow-cytometry of microbial biofilm samples, taken from six different sites along the stream monhaltorferAa. For details, consult the readme file and the associated publication

Temperature Experiment

Measurement of microbial biofilms single cells autofluorescence by flow cytometry, after exposure of the biofilm to an increase in temperature. For details, please consult the readme file and the associated publciation

Spatio-Temporal Patterns of Major Bacterial Groups in Alpine Waters

<div><p>Glacial alpine landscapes are undergoing rapid transformation due to changes in climate. The loss of glacial ice mass has directly influenced hydrologic characteristics of alpine floodplains. Consequently, hyporheic sediment conditions are likely to change in the future as surface waters fed by glacial water (kryal) become groundwater dominated (krenal). Such environmental shifts may subsequently change bacterial community structure and thus potential ecosystem functioning. We quantitatively investigated the structure of major bacterial groups in glacial and groundwater-fed streams in three alpine floodplains during different hydrologic periods. Our results show the importance of several physico-chemical variables that reflect local geological characteristics as well as water source in structuring bacterial groups. For instance, <i>Alpha</i>-, <i>Betaproteobacteria</i> and <i>Cytophaga-Flavobacteria</i> were influenced by pH, conductivity and temperature as well as by inorganic and organic carbon compounds, whereas phosphorous compounds and nitrate showed specific influence on single bacterial groups. These results can be used to predict future bacterial group shifts, and potential ecosystem functioning, in alpine landscapes under environmental transformation.</p></div

Heat-map of the Pearson correlations of beta-<i>proteobacteria</i> (<i>Bet</i>), alpha-<i>proteobacteria</i> (<i>Alph</i>), Cytophaga-Flavobacteria (<i>CF</i>), Eubacteria excluding <i>Alph</i>, <i>Bet</i> and <i>CF</i> (<i>EUBI-III_(undef)</i>) and not-defined DAPI positive cells (ND) to physico-chemical variables.

<p>Asterisk indicate the p-value (*: p<0.05; **: p<0.01; ***: p<0.001) of correlations between paired samples.</p

Biplot of the redundancy analysis based on the CARD-FISH data.

<p>Red symbols correspond to krenal sampling sites, whereas blue symbols depict kryal sites. Centroids of the respective probes are given: beta-<i>proteobacteria</i> (<i>Bet</i>), alpha-<i>proteobacteria</i> (<i>Alph</i>), Cytophaga-Flavobacteria (<i>CF</i>), Eubacteria excluding <i>Alph</i>, <i>Bet</i> and <i>CF</i> (<i>EUBI-III_(undef)</i>) and not-defined DAPI positive cells (ND). Arrows depict the forward selected physico-chemical variables. Asterisks depict significantly tested variables (* p<0.05, ** p<0.01). Explained variation for the first two constraint axes is given.</p

Dispersion ellipses fitted on the biplot of the redundancy analysis based on the CARD-FISH data constraint by physico-chemical variables (<b>Figure 3</b>).

<p>Dispersion ellipses split by catchments for different water sources and seasons are shown and depict the standard error of weighted average scores (confidence limit  = 0.95).</p

Map of the study sites in the three catchments, A: Val Roseg (VR), B: Loetschental (L) and C: Macun (M).

<p>Kryal sites are depicted in blue and annotated with an asterisk. Glaciers and the moraine area in VR and the sub-catchment in L are depicted in light grey and orange, respectively.</p

Microsatellite sequences Asterionella formosa

Microsatellite sequences of Asterionella formosa, containing the repeat units and forward and reverse primer sites

AFLP_data_Asterionella_formosa

AFLP fingerprint data of 91 isolates of Asterionella formosa (freshwater diatom) at 121 loci, from seven lakes in Switzerland and tree lakes in The Netherlands