PROBLEMS - Hydrogeology: Objectives, Methods, Applications - page 325

Answer:

Table 2 budget for fl ow from a stalactite in the Nerja cave (to be completed).

Average
concentration
(raw data)
(mg L -1 )

height of rainfall/
stalactite discharge
(mm/cm 3 j -1 )

Average
weighted
concentration
(mg L -1 )

C p : Cl - rain 8.20 764.3

C s : Cl - stalactite 30.18 5256.8

(weighted by
precipitation/discharge) (raw data)

R c = C p /C s
ER = P · R c _mm _mm

AET = P · (1 - R c ) _mm _mm

Table 3 budget for fl ow from a stalactite in the Nerja cave.

Average weighted
concentration
(mg·L -1 )

C p : Cl - rain 7.85

C s : Cl - stalactite 21.05

(raw data) (weighted by

precipitation/discharge)

R c = C p /C s 0.35 0.37

ER = P · R c 171 mm 183 mm

AET = P · (1 - R c ) 318 mm 307 mm

Problem #3—Exchanges between components of fl ow

The Fourbanne karst system (Charmoille, 2005) includes the Verne and
Luxiol swallow holes, diffuse infi ltration, and the passageways of the
Fontenotte cave, which plunge into the saturated zone and lead to the
Fourbanne karst spring (Figure 3). The water's path was traced using
fl uorescein at the Verne loss, and then sampled in Verne, Fontenotte, and
Fourbanne. The magnesium and nitrate concentrations of the traced mass
appear on Figure 3.

Question: How can you interpret the differences between these three
monitoring points?