Flow permanence and macroinvertebrate community variability in limestone spring systems

Limestone ( karst) springs within the River Wye catchment ( Derbyshire, U. K.) were investigated to examine the influence of physical and chemical characteristics and habitat variability on macroinvertebrate community composition. Flow permanence had a greater influence on the invertebrate community than any other physical or chemical variable examined. Clear differences in the macroinvertebrate community were observed between perennial (7) and intermittent springs (11) and the mainstem river. Springs support distinct communities, with some taxa exclusively recorded at the source or within the springbrook (e.g. Agabus guttatus [Paykull] and Micropterna lateralis [Stephens]). A degree of faunal overlap with the mainstem river occurred suggesting that perennial springs may form a refugium for many taxa and that intermittent springs are rapidly colonised by taxa from the mainstem river after the resumption of flow.