Table 3: Semivariogram model type, parameters for best fitted model (: nugget; : structural variance; : range), and cross-validation indicators (: determination coefficient; ME: mean error, NMSE: no dimensional mean square error) of the studied NH4-N, P, and K data sets.

LimeCodeModel/() (m)MENMSE

Ammonium nitrogen, -N

First sampling
0NH4-10Spherical1.0914.207.147.00.9230.0031.004
625NH4-11Spherical6.3710.4138.045.10.663−0.0110.994
1250NH4-12Spherical13.5819.0541.668.90.932−0.0160.926

Second sampling
0NH4-20Spherical0.0015.570.040.90.876−0.0031.147
625NH4-21Exponential0.0012.250.059.50.912−0.0050.992
1250NH4-22Exponential0.0013.080.049.80.869−0.0191.000

Third sampling
0NH4-30Spherical1.9524.157.553.20.639−0.0010.813
625NH4-31Spherical0.0033.960.071.90.9070.0020.922
1250NH4-32Spherical2.6013.9215.784.60.972−0.0080.937

Phosphorus, P

First sampling
0P-10Spherical0.231.5912.651.70.835−0.0521.060
625P-11Spherical0.611.5428.464.00.836−0.0031.020
1250P-12Spherical0.442.2916.153.00.8500.0020.903

Second sampling
0P-20Spherical0.424.868.065.20.951−0.0001.097
625P-21Spherical0.436.246.447.70.944−0.0190.996
1250P-22Spherical1.531.9743.776.30.908−0.0141.029

Third sampling
0P-30Spherical1.412.3038.073.90.9760.0020.848
625P-31Spherical0.742.1126.057.70.8430.0270.855
1250P-32Spherical0.892.2528.360.00.9120.0010.941

Potassium, K

First sampling
0K-10Spherical4.9746.749.659.70.8610.0111.184
625K-11Spherical6.5533.1216.554.20.903−0.0050.948
1250K-12Spherical15.9621.3542.851.40.9250.0130.901

Second sampling
0K-20Spherical6.7318.6526.565.50.8910.0060.954
625K-21Spherical14.6175.2016.352.30.8870.0490.863
1250K-22Spherical16.5643.7927.458.90.7830.0040.782

Third sampling
0K-30Spherical1.466.6618.063.10.899−0.0240.882
625K-31Spherical2.463.7139.968.20.9210.0031.075
1250K-32Spherical3.526.8434.076.80.960−0.0080.690