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Fig. 3 Plot of fractional storage volume (
A
s
/
A
) versus discharge (
Q
) for all studied streams pooled
from summer and spring
find that
k
1
scales approximately with
u
0.8
. Note that these values of
k
1
correspond
with a range of transient storage residence times ranging from about 2 to 22 min.
These values resonate with field observations.
Figure
3
shows the relationship between the ratio of transient storage volume to
main channel volume, expressed as an area ratio on the basis that the reach length
is common to both the stream channel and the transient storage zones (
A
s
/
A
) and
discharge (
Q
). We observe an inverse power law relationship between
A
s
/
A
and
discharge (
R
16). In this watershed, we find
A
s
/
A
scaling approxi-
mately with
Q
0.4
. We find for these streams that the transient storage volume varies
from about 10% to 70% of the main channel volume. Once again there is some
scatter, but these percentages seem reasonable when we consider in situ observa-
tions. The value of
A
s
/
A
obtained at the lowest flow appears to be an outlier, indeed it
may reside in a different flow regime. If it were not included in the regression, the
correlation would likely become stronger and the exponential decline steeper.
¼
0.475,
n
¼
5.2 Seasonal Analysis
We observed several types of potential transient storage zones in these streams:
seasonal development of aquatic plants, permanent moss cover, stones and deep
pools. Table
1
summarises our expectations and observations. Generally, streams
with large swathes of submerged and emergent aquatic vascular plants had less
transient storage at the beginning of the spring (April 2009) than in late summer
(August 2008), see Table
1
and Fig.
4
, reflecting previous findings (Salehin et al.
2003
; Ensign and Doyle
2005
). The change in predicted transient storage in the
