Environmental Engineering Reference
In-Depth Information
Figure 14.15
The influence of drainage basin character on
individual flood hydrographs. PDV and lag time vary
according to shape, network and slope. Note how PDV falls
as lag times increase, conserving the 'area under the curve'
or total discharge.
Source: After Gregory and Walling (1973).
CHANNEL EROSION AND SEDIMENT TRANSFER
Fluvial sediment transfer is the prime agent of the third component of continental
denudation, after weathering and mass wasting. Sediment is sourced directly by channel
erosion, augmented by fine-grained debris from overland flow and dissolved sediment in
throughflow and ground water. Most material, however, is delivered to the channel by
mass wasting on surrounding slopes. Sediment is also derived from anthropogenic ground
disturbance by agriculture, quarrying, construction and land degradation. General
processes of entrainment, transport and deposition outlined in Chapter 12 have specific
