Disturbance history influences the distribution of stream invertebrates by altering microhabitat parameters: a field experiment
2008 (English)In: Freshwater Biology, Vol. 53, no 5, 996-1011 p.Article in journal (Refereed) Published
1. We investigated the effects of local disturbance history and several biotic and abiotic habitat parameters on the microdistribution of benthic invertebrates after an experimental disturbance in a flood-prone German stream. 2. Bed movement patterns during a moderate flood were simulated by scouring and filling stream bed patches (area 0.49 m(2)) to a depth of 15-20 cm. Invertebrates were investigated using ceramic tiles as standardized substrata. After 1, 8, 22, 29, 36 and 50 days, we sampled one tile from each of 16 replicates of three bed stability treatments (scour, fill and stable controls). For each tile, we also determined water depth, near-bed current velocity, the grain size of the substratum beneath the tile, epilithic algal biomass and standing stock of particulate organic matter (POM). 3. Shortly after disturbance, total invertebrate density, taxon richness and density of the common taxa Baetis spp. and Chironomidae were highest in stable patches. Several weeks after disturbance, by contrast, Baetis spp. and Hydropsychidae were most common in fill and Leuctra spp. in scour patches. The black fly Simulium spp. was most abundant in fill patches from the first day onwards. Community evenness was highest in scour patches during the entire study. 4. Local disturbance history also influenced algal biomass and POM standing stock at the beginning of the experiment, and water depth, current velocity and substratum grain size throughout the experiment. Scouring mainly exposed finer substrata and caused local depressions in the stream bed characterized by slower near-bed current velocity. Algal biomass was higher in stable and scour patches and POM was highest in scour patches. In turn, all five common invertebrate taxa were frequently correlated with one or two of these habitat parameters. 5. Our results suggest that several 'direct' initial effects of local disturbance history on the invertebrates were subsequently replaced by 'indirect' effects of disturbance history (via disturbance-induced changes in habitat parameters such as current velocity or food).
Place, publisher, year, edition, pages
2008. Vol. 53, no 5, 996-1011 p.
IdentifiersURN: urn:nbn:se:umu:diva-31470ISI: 000254808400014ISBN: 0046-5070OAI: oai:DiVA.org:umu-31470DiVA: diva2:293181
Effenberger, Michael Engel, Johanna Diehl, Sebastian Matthaei, Christoph D.2010-02-102010-02-102010-02-10