Microdistributions of stoneflies of the High Tatra montane streams

Stonefly samples were collected from disturbed and undisturbed tributaries of the Tatra Mountains streams (the West Carpathians). In the autumn, at stable low discharge, the total density of stoneflies was significantly higher in the undisturbed streams. Microhabitats such as macrolithal (boulders), mesolithal (stones) and moss had higher stonefly density. Taxa of different species or genera have different demands for microhabitats. Very narrow spatial niches were found for the genera Rhabdiopteryx, Protonemura and Perlodes. The spatial niche overlap was low between the genera Rhabdiopteryx and Brachyptera, but was high between species of the Protonemura and Leucra genera. The highest biodiversity of stoneflies was on coarser substrata (except boulders) and moss, the lowest biodiversity was on the finer substrata. Among the organic substrata, a significantly lower coefficient of stonefly α-diversity variation was recorded in mosses compared to submerged wood and roots

Community structure, life histories and secondary production of stoneflies in two small mountain streams with different degree of forest cover

Our study examines community structure and nymphal biology (life cycles and secondary production) of stoneflies in two adjacent mountain streams with different degree of forest cover in the Prosiečanka River Basin (Chočské Vrchy Mts., West Carpathians). One of the streams has non-forested catchment, converted to meadows and pastures, while the other one has catchment with 60% covered by spruce forest. Differences in forest cover and in thermal regime of the streams were reflected by the difference of stonefly communities at their structural and functional level. Species Nemoura cinerea and Leuctra aurita created stonefly assemblage in non-forested stream, whereas Nemoura cinerea also occurred in naturally forested stream together with species Leuctra armata, Leuctra nigra, Leuctra prima, Siphonoperla neglecta and Arcynopteryx dichroa. All examined species had maximally annual life cycle and in eudominant species Nemoura cinerea one month shift was found in nymphal hatching and adult emergence between streams. Total secondary production of stoneflies in undisturbed stream (126.46 mg DW m-2 y-1) was more than two times higher than the production in non-forested stream (47.39 mg DW m-2 y-1). </p