Original paper
The influence of flooding and river connectivity on macroinvertebrate assemblages in rheocrene springs along a third-order river
von Fumetti, Stefanie; Dmitrović, Dejan; Pešić, Vladimir
Fundamental and Applied Limnology Volume 190 Nr. 3 (2017), p. 251 - 263
published: Aug 1, 2017
published online: Jul 6, 2017
manuscript accepted: Jun 12, 2017
manuscript received: Feb 28, 2017
ArtNo. ESP141019003007, Price: 29.00 €
Abstract
Abstract Springs are spatially restricted ecotones usually found at the beginning of a headwaters continuum, which provide distinct environmental conditions, and are inhabited by invertebrate spring specialists called crenobionts. Springs along rivers of higher order with short springbrooks oppose the classical eucrenal-hypocrenal-epirhithral continuum and may be colonised differently. Here, 35 rheocrene springs along the river Cvrcka in the Dinaric Karst are investigated, with the aim to identify the role of river connectivity on the species assemblages in springs, and to test whether the large proximity of some springs influences the similarity of their species composition. Species assemblages are strongly dominated by generalist rhithrobiontic taxa, which also occur in the adjacent river. Flooding significantly influences the composition of the species assemblages, with a higher share of rhithrobiontic taxa in flooded springs. Connectivity and distance to the river do not have a significant influence, and spatial proximity is not an indicator for assemblage similarity. The springs are strongly influenced by the river Cvrcka. We conclude that dispersal and colonisation mainly take place via the watercourse corridor by insects in adult stages. Conservation strategies must take into account the special character of riparian springs along large rivers.
Keywords
eucrenal • spring specialists • rhithrobiontic taxa • dispersal