Predicting model

R²

RMSE

F

Sig.

1

CEC₁ = 3.453 − 0.024pH − 0.078OM + 0.137Fe₂O₃ + 0.013Silt − 0.003Clay

0.450

3.60

2.94

0.041

2

CEC₂ = 5.022 − 0.569pH − 0.100OM + 0.185Fe₂O₃ + 0.011Silt + 0.003Clay

0.550

3.64

4.41

0.009

3

CEC₂ = 1.418 + 1.095CEC₁

0.859

1.84

133.70

0.000

4

CEC₂ = 1.665 − 0.546pH − 0.024OM + 0.053Fe₂O₃ − 0.001Silt + 0.007Clay + 0.972CEC₁

0.923

1.55

33.81

0.000

5

CEC₃ = 4.452 − 0.438pH − 0.136OM + 0.180Fe₂O₃ + 0.010Silt + 0.003Clay

0.543

3.49

4.27

0.010

6

CEC₃ = 1.038 + 1.035CEC₁

0.843

1.85

118.46

0.000

7

CEC₃ = 1.222 − 0.415pH − 0.063OM + 0.052Fe₂O₃ − 0.002Silt + 0.006Clay + 0.935CEC₁

0.922

1.49

33.34

0.000