HR: 09:15h
AN: NB21A-04 INVITED     [Abstracts]
TI: Spatial and Temporal Patterns of Aquatic Habitats in a Karstic Environment: Implications for the Stream Biota From Species to Community Level
AU: * Meyer, E I
EM: meyere@uni-muenster.de
AF: Elisabeth Irmgard Meyer, University of Muenster, Institute for Animal Evolution and Ecology, Department of Limnology, Muenster, 48149 Germany
AB: Due to the specific geohydrological situation, the investigated drainage network of the Paderborner Hochflaeche (North-Rhine Westphalia, Germany) shows typical karst features like sinkholes, dolines, underground caves, dry valleys, and karst springs. Many streams are characterized by spatial and temporal flow intermittency. The objectives of the study were to elucidate temporal and spatial flow patterns, invertebrate distribution and species-specific adaptations. It was hypothesized that different hydrological stream sections are characterized by different lotic communities. It was further assumed that in temporary stream sections a high proportion of the benthic assemblages consists of species adapted to the harsh abiotic conditions either by strategies of resistance or of resilience. Most of the streams are summerdry, and drought duration increases with increasing distance from the perennial upstream sections. However, depending on the precipitation, sudden flash flows may occur. Particularly in small streams permanent springs and springbrook sections can be observed locally. Lotic communites differ in the different hydraulic habitats, and experiments on the species level give evidence for species-dependent plasticity in life history traits or for behavioural adaptations. It can be concluded that temporary karst streams contribute to regional biodiversity, which might be threatened by management practices.
DE: 1812 Drought
DE: 1845 Limnology
SC: North American Benthological Society [NB]
MN: 2005 Joint Assembly