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

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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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