Slopewash processes in an arctic tundra environment, Banks Island, Northwest Territories.

The magnitude and frequency of slopewash processes in a permafrost environment were examined during the summer of 1977. Small instrumented plots were set up and monitored for surface runoff at one interfluve and two valley-side locations. Subsurface water was collected at two of the sites using guttering positioned at various depths in the active layer. Snowmelt was the major source of both surface aid subsurface runoff, and summer precipitation was of little importance. Volumes of surface runoff were generally greater than those of subsurface flow, although both varied with position on the slope. Partial area contribution to streamflow was usual, the source areas being those conducive to snowbank formation. Measurement of the amounts of suspended and dissolved sediment indicated that surface wash was a more important transport agent than subsurface wash. Both processes, however, appeared to be of limited importance at the interfluve location, and only transported significant amounts of sediment at the valley-side sites where large snowbanks ablated