Geoscience Reference
In-Depth Information
12
6
Evolutionary line
Nearsurf
a
ce
riparian
y = 2.846 2e
0. 5552x
R
2
=0.85
10
5
8
4
6
Deepriparian
groundwater
3
Baseflow
Storm started
1.5 hrs afterpeak storm
Storm end
Poststorm
4
2
Baseflow
Stormstarted
15 hrs afterpeak storm.
Stormend
Poststorm
2
1
Hillslope
soilwater
0
0
0
0.2
0.4
0.6
0.8
1
0
2
4
6
8
10
12
Proportion of runoff (unitless)
Ca
2+
(mg/L)
(a)
(b)
Fig. 4. Relationship between contribution of NSR to runoff and change of stream Ca
2+
concentration (a) and mixing diagram of Ca
2+
and SiO
2
during August 21-22, 2001
storm.
6
DRG
HSW
NSR
5
4
NSR
3
DRG
2
1
HSW
0
0
2
4
6
8
Total discharge (L/s)
Fig. 5. Relationship between discharge and Ca
2+
flux during storm event on August 21-
22, 2001. NSR: near surface riparian; DRG: deep riparian groundwater; HSW: hillslope
soil water.
in the NSR suggesting that the rate of transport was superior to that of
dilution of the weathered Ca
2+
.
Those phenomena explain well that Ca
2+
has progressively deteriorated
during the hydrologic event. As discharge increased Ca
2+
flux increased
linearly (Fig. 5). The Ca
2+
flux in the NSR was higher than that in the
DRGaswellasintheHSW.Intheriparianzone,Ca
2+
concentration
increased away from the stream and decreased at the border between the
