The Dynamics of Coarse Sediment Transfer in an Upland Bedrock River

摘要: Bedrock channels in UK upland environments have received relatively little attention despite their importance within river systems and influence on controlling the conveyance of sediment downstream. This thesis aims to quantify model transfer coarse through Trout Beck, an bedrock reach North Pennines, UK. The transport has been quantified field monitoring characteristics, repeat magnetic tracer surveys situ bed load impact sensors. was carried out conjunction with channel morphology, using terrestrial laser scanning dGPS continuous flow monitoring. enabled dynamics be related hydraulic conditions throughout reach. Differences between types conceptualised continuum ‘fluvial trinities’. demonstrates that interaction morphology is partly disconnected channels. Conversely, partially alluvial there are important feedbacks stored locally channel, form transport. It shown bedrock, sections a considerable varied these reaches. Sediment storage defines very reaches, except hydraulically sheltered sites. More efficient result local hydraulics. low resistance stable boundaries cause downstream full grain-size distribution during periods when competent supplied from external sources. The detailed morphological survey provided necessary boundary conditions, along data, apply one-dimensional (HEC-RAS) channel. modelling results regime Furthermore, shear stress as proxy for transport, potential dominant (16-256 mm) assessed different locations There significant differences critical threshold down Sediment which transported will deposited stored, reach, at same conditions. As magnitude increases above threshold, whole until sediment. always greater than By combining modeling approaches improved understanding thresholds spatial variations achieved.