Quadratic forms of calibrations, And electrical conductivity at saturation 0.4 ds m, For both – Campbell Scientific CS616 and CS625 Water Content Reflectometers User Manual
Page 34: Linear and quadratic forms, Both linear and quadratic forms
CS616 and CS625 Water Content Reflectometers
FIGURE 7-3. Difference in % volumetric water content between linear
and quadratic forms of calibrations
The linear and quadratic coefficients for the sandy clay loam data in FIGURE
7-3 follow and can be used in similar soils.
TABLE 7-2. Calibration coefficients for sandy clay loam with bulk density 1.6 g cm
-3
and
electrical conductivity at saturation 0.4 dS m
-1
for both linear and quadratic forms.
Linear
Quadratic
C0
C1
C0
C1
C2
–0.6200
0.0329
0.0950
–0.0211
0.0010
TABLE 7-3. Calibration coefficients for sandy clay loam with bulk density 1.6 g cm
-3
and
electrical conductivity at saturation 0.75 dS m
-1
for both linear and quadratic forms.
Linear
Quadratic
C0
C1
C0
C1
C2
–0.4470
0.0254
–0.0180
–0.0070
0.0006
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