Patchiness in flow refugia use by macroinvertebrates following an artificial flood pulse

Flow refugia, locations that maintain substrate stability and low hydraulic stress during periods of high flow, can ensure riverine resilience in the face increasing hydrological unpredictability. Despite their known importance, they have been overlooked recent years with work on drought refugia currently seeing greater attention. Moreover, research role flow artificial flood pulses regulated rivers, where disturbances are no longer part hydrograph, is essentially absent. Here, we compared for benthic macroinvertebrates among six habitats (main channel, side riffle, margin, lentic including a floodplain pond, inundated floodplain) within four different sites response to an pulse. We found grain-size distribution macroinvertebrate community composition changed at each site following flood. Macroinvertebrate assemblages became longitudinally homogeneous, but within-site beta diversity taxa richness remained temporally stable pulse, suggesting presence refugia. In this respect, (a pond) provided important locations, particularly mobile mayfly Rhithrogena sp. contrast, riffle channels resulted limited potential most taxa. Refuge use was however patchy levels intra-habitat variability being evident amphipod Gammarus fossarum margin channel habitats. Further required advance our knowledge rivers differing regimes enable integration into management restoration schemes.