The chemistry, mineralogy, and rates of transport of sediments in the ...

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log Pra -
1 .0892 + 0 .9073 log Ad + 1 .1828 log AE
-2 .8210 log F, R2 - 0 .98 ; ( 2 )
log PWg - 1 .0243 + 1 .1333 log Ad + 0 .6353 log AE - 3 .3231 log F,
R2 - 0 .97 ; (3)
log PE - 4 .5434 + 1 .0059 log Ad + 1 .8438 log AE - 2 .0173 log P
and
- 3 .7420 log F, R 2 - 0 .98 ; ( 4 )
log •STQ - 8 .8995 + 1 .2741 log
Ad + 1 .1417 log AE - 2 .6367-log P
- 6 .1278 log F, R2 - 0 .98 ( 5 )
These predictive relationships would likely be improved by inclusion of
meterorological and soil-permafrost-vegetation parameters, by increased
frequency of sampling, and a more widespread geographic distribution of river
discharge, suspended sediment, and chemical measurement stations . In particular,
small mountain streams and intermediate sized rivers (i .e . Hare Indian,
Horn, Blackwater, North Nahanni, Root Rivers) are not represented in our data
set .
DISCUSSION
The UsefulnessofRelationshipsBetweenConcentrationsofParticulate_
Material andDischarge
As shown in Figs . 1, 3, 4 and Table 2, the concentrations of suspended
sediments (SS4), and to a lesser extent particulate phosphorus (PP,), particulate
nitrogen (PNi), and particulate carbon (PCB), vary in logarithmic
proportion with discharge (Qi) . Such relationships (usually only for SS,)
have been investigated in Temperate Zone rivers by Leopold et al . (1964,
p : 220) and Abrahams and Kellerhalls (1973) . Sediment rating curves, such
as Fig . 1, have been used to estimate, suspended sediment concentrations
between sampling dates (such as in Davies, 1974) . Abrahams and Kellerhalls
(1973) suggest that, with careful evaluation of 5-9 years of data, these
relationships may be useful in predictive estimation of sediment concentrations
and rates of transport of sediments . When a longer period of
measurement of Qi and SSi is available,, these relationships (Fig . 1) could
contribute to a method to observe the effects of terrain disturbance on
suspended . sediment loads of smaller rivers and streams (i .e . similar in
size and character to the rivers of Group 2 in Table 1) . If there have been
no recent natural erosion events (fires or landslides) in a watershed under
technological development (e .g ., rights-of-way clearing for pipelines or
roads), then Qi and SSi data points that fall greatly above the regression
lines (or their confidence limits, not shown) in Fig . 1 might indicate