Geography Reference
In-Depth Information
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Figure 14.8 Reach-based study (90m) of the Kingsdale Beck, Yorkshire containing in excess of 20 million points (a), allowing
identification of roughness elements highlighted in (b) in the channel at the micro-topographic (individual clast) scale.
the sediment fluxes occurring over short timescales with
deposition masking erosion to generate an inaccurate
underestimate of material movement through the reach.
of deeper pool areas associated with inner bank point
bar deposits, sinuous reaches and shallow steep riffle sites
(Figure 14.10).
Terrestrial laser scanning of the unregulated 250m
reach of the river upstream of Catcleugh Reservoir in
Northumberland (Milan et al., 2010) utilised a rapid
data acquisition protocol utilising surveyed reflectors;
scanning the river from alternate sides ensured overlap
with the previous scans. Six instrument setups generated
a detailed composite point cloud image (Figure 14.11). It
is immediately obvious from this point cloud dataset that
14.2.7 Reach-scalemorphological analyses
The River Rede is a headwater tributary of the North Tyne
(catchment area
18 km 2 ) with a bankfull discharge of
8.5m 3 s 1 . It is flashy in nature and experiences substan-
tial bedload movement beginning at 23-35% bankfull
(Milan et al., 2001). The mobile gravel and cobble mate-
rial have created a well-defined morphology, consisting
=
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