SOCa SOCa SOCa SOCa SOCa SOCa SOCa
5cm 20cm 80cm 140cm 200cm Crop Robinia pseudoacacia
F Correlation coefficient -0.233 0.258 0.172 0.249 0.332 0.710 0.680
P-value 0.064 0.037* 0.168 0.044* 0.007** <0.001** <0.001**