Table 2 Values of the fitted parameters of the root distribution model for the two trees of the G trial and all the trenchs of the PN trial

Pipe coefficient (pipe_coef)

0.029

0.045

0.077

Exponent coarse root distribution (exp_distr)

−0.5

−0.49

−1.38

Distance peak fine root frequency (d_frf)

2.5

2.1

6.4

Weibull coef. for fine root distribution (w.coef)

2.4

2.1

6.2

Coarse root proportionality factor (red_coef)

2.5

3.4

0.18

Maximum root spread coefficient (max_dist_coef)

74

88

14

Error variance (var)

0.17

0.08

4.25