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Lithologic Fingerprints Dissolution Rates Human Influence

Cl [mg/L] MAP [mm/yr] % Ag.
<15 <1100 <10
15-30 1100-1200 10-25
30-40 1200-1300 25-50
40-60 1300-1400 50-75
>60 >1400 >75

50
A B C Km
SO [mg/L] Cond. [µS] E Coli [MPN/100 mL]
4
<15 <250 No data 200-500
15-25 250-400 <85 >500
25-35 400-600 85-200
35-60 600-1000
>60 >1000

D E F
HCO [mg/L] TDS [mg/L] TDN [mg/L]
3
<150 <200 <0.5
150-200 200-400 0.5-0.75
200-250 400-600 0.75-1
250-350 >600 >1
>350

G H I

SiO [mg/L] Chem. denud. [t km yr ] PO (P) [mg/L]
-2
-1
3
2
<10 <100 150-200 0.1
10-20 100-150 200-250 0.2
20-30 >250 0.4
30-40 0.6
>40 0.8
J K L
¹ ! 124 Sampled basins and Ultramafic K [mg/L]
104

pE Marine Strata
<1.0
bedrock lithology
1.0-1.5
uC Marine Strata

2.0-2.5
Amphibolites
! ! 106 119 Metamorphic 1.5-2.0
Plutonic >2.5
122 107 Undivided
132 D I ! 118 Volcanic
! 109 Other
A ! ! 108 ^ Reservoirs
120 ! ! 121 ^ ! ! Sample sites M
! Watersheds
131 ! ! !
102 16 DOC [mg/L]
^ ! C,F,H 115 <2
B ! 2-3.5
114 ^ 111 3.5-4.5
! ^ ! 4.5-8
!
! 15
! >8
! !
101 ! 117
E 116 G 14
110 !
25
N Km 113 ! O
Figure 3. Results of river water biogeochemical analyses plotted for 25 sampled basins. (A) Chloride. (B) Mean annual precipitation. (C) Percent agricultural land
use. (D) Sulfate. (E) Conductivity. (F) E. coli. (G) Bicarbonate. (H) Total dissolved solids. (I) Total dissolved nitrogen. (J) Silica. (K) Chemical denudation rate.
(L) Orthophosphate as phosphorus. (M) Potassium. (N) Sampled basins overlain on generalized geological map (French and Schenk, 2004). Letters show location
of photos in Figure 2. Four basins (CU-120, -121, -122, and -132 labeled with red text and points) have distinct water chemistry. Dots represent sample sites. Stars
shows reservoir water samples (Betancourt et al., 2012). (O) Dissolved organic carbon.
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