Discharge regime and the effect of drying on macroinvertebrate communities in a temporary karst stream in East Westphalia (Germany)

Abstract

The special hydrological situation of temporary streams has a great influence on the abiotic processes and other habitat conditions for organisms. To monitor possible impacts of stream drying on the composition of lotic communities, streamflow measurements and collections of the macrozoobenthos were conducted in a temporary and an adjacent upstream permanent section of the karst stream Sauer (East Westphalia, Germany) in 1996. The Sauer has a summer-dry temporary flow regime. The seasonal dry phase can last from spring to early autumn, so the duration of the dry phase varies from one to several months, increasing with distance downstream from the upstream permanent section. The number of invertebrate taxa and individuals decreases with increasing duration of the dry phase. The permanent section is characterized by taxa typical of montane and submontane streams, whereas the fauna of the temporary section is quite different, composed of representatives of various zonal areas. Limnephilid caddisflies are particularly characteristic of this section. Life cycle strategies and specific adaptations with respect to habitat drying are discussed for several species. It can be concluded that the temporary discharge regime of the karst stream Sauer has a clear effect on the invertebrate communities. They mainly consist of species which can be seen as characteristic faunal elements of temporary streams.

From isolation to connectivity: the effect of floodplain lake restoration on sediments as habitats for macroinvertebrate communities

“…A decrease in the flow rate modifies habitat conditions in ecosystems and leads to changes in biogeochemical processes (Zalewski 2006) and aquatic fauna (Gallardo et al 2012;Obolewski et al 2016). Inhibited flow generally decreases the density and abundance of invertebrate species (Meyer and Meyer 2000;Boulton 2003) and leads to changes in the size and age structure of hydrobiont populations (Lake 2003). The results of our study indicate that floodplain ecosystems are more likely to thrive in RFS characterized by a partial parapotamal rather than parapotamal phase.…”

Assessment of Temporary Streams: The Robustness of Metric and Multimetric Indices under Different Hydrological Conditions

“…Future research should be done covering the complete organic degradation gradient and extended to temporary streams from other latitudes (Olson & Soderstrom, 1978;Sommerhauser et al, 1997;Meyer & Meyer, 2000).…”

“…The relatively harsher environmental conditions experienced in temporary streams have been used to explain this reduced species abundance and richness (Boulton & Suter, 1986). During the flow period, precipitation may originate floods which cause disturbances, varying from small movements of substrate, to large changes in the system structure and in the morphology of the stream channel, such as detritus exportation, sediment deposition and the dislodging of biological communities (Boulton & Suter, 1986;Resh et al, 1988;Townsend, 1989;Stanley et al, 1994;Lake et al, 1998;Meyer & Meyer, 2000). The effect of these hydrological events is one of the principal environmental factors influencing the structure and function of macroinvertebrate communities in Mediterranean streams (Langton & Casas, 1998;Prenda & Gallardo-Mayenco, 1996;Prenda & Gallardo-Mayenco, 1999;Puig et al, 1991;Ubero-Pascal et al, 2000).…”

Microbial mats as shelter microhabitat for amphipods in an intermittent karstic spring

“…Karst spring discharges reflect periods of poor or abundant precipitations due to specific recharge conditions and the locally prevalent climate regime (Bonacci, 2015;Fiorillo et al, 2015). In such conditions streamflow regime is recognized as the principal variable affecting the success and distribution of aquatic biota (Meyer and Meyer, 2000;Meyer et al, 2003;Konrad et al, 2008). Limited knowledge of the effects of temporary seasonal drying of karst springs on stream biota introduces numerous questions when comparing biological integrity of these specific habitats to perennially flowing streams (Reiss and Chifflard, 2015).…”