Soil depth (cm) Pearson“s correlation coefficient R2
0-20 0.948** 0.899
20-40 0.900** 0.810
40-60 0.828** 0.685
60-80 0.727** 0.528
80-100 0.589** 0.347
100-120 0.496** 0.247
120-140 0.380** 0.144
140-160 0.247** 0.061
160-180 0.140 0.020
180-200 0.094 0.009