This paper details a basic method for estimation of both bed material
yield and supply rates for a glaciated catchment. Recent research has
illustrated the potential of morphological methods for the estimation
of bed material transport rates, but also raised important
methodological issues, notably regarding the requisite spatio-temporal
resolution of morphological data and the need for either information on
upstream sediment supply or assumptions about typical distances of
particle movement during transport. Both of the latter have proved
problematic. This paper provides an additional means of estimating bed
material transport rates and yields through the combination of a simple
process-based relationship with morphological information. For a short
reach of gravel-bed stream, in a glaciated catchment with a
characteristic diurnal discharge hydrograph, a strong positive
relationship was found between the volume of water passing through the
reach and the volume of erosion in the reach, for points early on the
rising limb of the hydrograph. This relationship broke down later in
the hydrograph, notably after the discharge peak, associated with the
advent of sediment supply from upstream. Thus, early in the hydrograph,
this relationship provides an indication of the capacity of this reach
to move sediment, either locally eroded material or sediment supplied
from upstream, and this paper applies this relationship to a six week
discharge hydrograph to predict the potential transport volumes. From
these predictions, it calculates the minimum volume of bed material
that must have been supplied to the reach from upstream, per hour, to
maintain its observed elevation. The results are used to illustrate and
discuss some of the problems associated with the use of morphological
information for the estimation of bed material transfer rates. (C) 1997
Elsevier Science B.V.