Magnitude and frequency of bedload transport was examined in the Lainbach River, Bavaria, using magnetically tagged particles. During the study, 18 small to moderate events and one major event occurred. About 1 per cent of the flow period exceeded the entrainment threshold and at least once every year about 50 per cent of the tagged particles were mobile. Themajor event which occurred during the study period resulted in the deposition of a thick layer of sediment in parts of the channel and passive burial of most of the recovered particles. The step-pool pattern, which characterized the study site prior to the large event, was obliterated. However, the channel recovered quickly and has returned to a new step-pool pattern. The event changed the boundary conditions by increasing the availability of loose sediment and creating higher river-bed slopes in reaches between breached check dams. As a result, movement of individual particles measured for events of both the same magnitude and duration, occurring before and after the large event, yielded different values. For events which occurred after the large event, the range and the mean distance ofmovement were about ten times higher.

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In the Latnjavagge drainage basin (68°21′N, 18°29′E), an arctic‐oceanic periglacial environment in northernmost Swedish Lapland, the fluvial sediment transport and the characteristics and importance of high‐magnitude/low‐frequency fluvial events generated by intense snowmelt or heavy rainfall have been investigated and compared with snowmelt‐ and rainfall‐induced discharge peaks in the Levinson‐Lessing Lake basin (Krasnaya river system) on the Taimyr Peninsula, an arctic periglacial environment in northern Siberia (74°32′N, 98°35′E). In Latnjavagge (9 km2) the intensity of fluvial sediment transport is very low. Most of the total annual sediment load is transported in a few days during snowmelt generated runoff peaks. Due to the continuous and very stable vegetation covering most areas below 1300 m a.s.l. in the Latnjavagge catchment, larger rainfall events are of limited importance for sediment transport in this environment. Compared to that, in the c. 40 times larger Krasnaya riversystem rainfall‐generated runoff peaks cause significant sediment transport. The main sediment sources in the Latnjavagge drainage basin are permanent ice patches, channel debris pavements mobilized during peak discharges and exposing fines, and material mobilized by slush‐flows. In the Krasnaya river system river bank erosion is the main sediment source. In both periglacial environments more than 90% of the annual sediment yield is transported during runoff peaks. The results from both arctic periglacial environments underline the high importance of high‐magnitude/low‐frequency fluvial events for the total fluvial sediment budgets of periglacial fluvial systems. Restricted sediment availability is in both arctic environments the major controlling factor for this behaviour.

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