Bed load transport in a steep snowmelt-dominated mountain stream as inferred from impact sensors

Abstract

The article reports results from bed load transport investigations using impact sensors in Vinstra, a steep snowmelt-dominated mountain stream in Central Norway. The impact sensors proved able to detect thresholds for bed load entrainment. With increasing discharges surpassing the threshold for entrainment, both the magnitude and variance in impact force increases, but also showing differing rating relationships on rising and falling flows. Substantial bed load transport was only observed during the snowmelt-dominated spring flood period and impact magnitude was observed on average to follow diurnal variations in discharge during the spring flood event, but with a clockwise hysteresis relationship.

Keywords:

• bed load entrainment
• impact sensors
• mountain stream

Acknowledgements

D. Gintz and M. Hassan are thanked for their reviews of this paper which resulted in considerable improvement to it.

Notes

1. Geological Survey of Norway, Trondheim (www.ngu.no accessed 30 March 2007)

2. Tinytag Plus Shock (0–100 g) (www.geminidataloggers.com accessed October 2007)