TY  - JOUR
AB  - The disturbing effect of a short-term cooling period during summer on planktonic bacterial community structure of an alpine lake was investigated using 16S rDNA pyrosequencing. Proteobacteria, Actinobacteria, and Bacteroidetes constituted the most abundant phyla. During the sampling period (from July to August 2010), a sudden cooling period with high precipitation occurred, as indicated by a decrease in conductivity, calcium, and dissolved organic carbon concentration resulting from increased runoff. The relative abundance of Actinobacteria, Betaproteobacteria, and Cyanobacteria decreased during this short-term cooling period. Instead, a rapid shift from Betaproteobacteria to Gammaproteobacteria occurred, which was mainly caused by an increase of Acinetobacter rhizosphaerae. Soon after the short-term cooling period, warmer weather conditions got re-established and Betaproteobacteria recovered and became again dominant. Non-metric multi-dimensional scaling analysis and Venn diagrams revealed a planktonic bacterial community composition with high similarity at the beginning and the end of the growing season. Air temperature and precipitation were significantly correlated with the observed variation in operational taxonomic unit (OTU) relative abundance. It is concluded that, in response to the short-term cooling period, a distinct planktonic bacterial OTU community developed. It rapidly diminished, however, as summer conditions became re-established, implying the recovery of the original bacterial community structure.
AU  - Ma, T.
AU  - Jiang, Y.
AU  - Elbehery, A.H.A.
AU  - Blank, S.*
AU  - Kurmayer, R.*
AU  - Deng, L.
C1  - 57415
C2  - 47754
CY  - Van Godewijckstraat 30, 3311 Gz Dordrecht, Netherlands
SP  - 535-548
TI  - Resilience of planktonic bacterial community structure in response to short-term weather deterioration during the growing season in an alpine lake.
JO  - Hydrobiologia
VL  - 847
IS  - 2
PB  - Springer
PY  - 2020
SN  - 0018-8158
ER  - 

TY  - JOUR
AB  - At regional and catchment scales, geology and hydrogeology strongly influence the distribution of groundwater invertebrates (stygofauna), but the fine scale distribution of stygofauna in sedimentary aquifers remains poorly studied. In this study, we examine the small-scale distribution of stygofauna in sediments of a perched aquifer in an upland swamp in south eastern Australia. We installed a series of piezometers which accessed either the full sediment profile or one of four discrete sedimentary layers in the swamp. Piezometers were sampled for stygofauna and 2H and 18O isotopes in the groundwater. The swamp contained a taxonomically diverse and abundant stygofauna, which was distributed throughout the swamp and similar in composition to that of other aquifers in the region. There were strong temporal changes in the faunal assemblages but the stimuli for these changes remain unknown. Isotope analysis indicated that the swamp water was well mixed despite localised inputs of groundwater from springs. Accordingly, we could not explore the relative influence of groundwater inputs on fauna; however, we have shown clearly that stygofauna were strongly influenced by sediment properties, with the abundance of stygofauna in the dense, fine sandy sediments being significantly lower than in the coarser sedimentary layers above and below.
AU  - Hose, G.C.*
AU  - Fryirs, K.A.*
AU  - Bailey, J.*
AU  - Ashby, N.*
AU  - White, T.*
AU  - Stumpp, C.
C1  - 50841
C2  - 42913
SP  - 145-157
TI  - Different depths, different fauna: Habitat influences on the distribution of groundwater invertebrates.
JO  - Hydrobiologia
VL  - 797
IS  - 1
PY  - 2017
SN  - 0018-8158
ER  - 

TY  - JOUR
AB  - The exchange of water with groundwater is a key determinant of water quality and faunal assemblage. Water exchange not only occurs with running waters, but also through percolation, interception (soil, porous alluvium), and evaporation. The aim of this study was to identify how different types of exchange were related to the groundwater faunal assemblage of an alluvial aquifer. Hydrological exchange is largely governed by pore space and thus ultimately by geological formation. In the Marbling Brook catchment of Western Australia the different geological formations did not eventuate in hydrochemically distinct groundwater zones. The cluster analysis of faunal assemblages revealed five groups within the faunal samples which did not reflect spatial patterns such as geological, chemical or topographic features. Discriminant analysis showed that these five groups were best characterized by a range of abiotic features including dissolved oxygen, land-use, and temperature. These variables signal different types and intensities of exchange with the surface.
AU  - Schmidt, S.I.
AU  - Hahn, H.J.*
AU  - Hatton, T.J.*
AU  - Humphreys, W.F.*
C1  - 1795
C2  - 24412
SP  - 1-19
TI  - Do faunal assemblages reflect the exchange intensity in groundwater zones?
JO  - Hydrobiologia
VL  - 583
IS  - 1
PB  - Springer
PY  - 2007
SN  - 0018-8158
ER  -