Table 2.

Connectivity parameters and simulation results of barley rhizosphere

Treatment	${\mathrm{\Gamma }}_p$ total	Percolation threshold (μm pore size)	Pore volume fraction (saturated pore volume fraction) (−)	Simulated D eff (−)	Simulated k (× 10−6 cm2)
No hairs WD	0.81 ± 0.23	53 ± 13	0.22 ± 0.07 (0.69 ± 0.08)	0.78 ± 0.12	1.48 ± 0.83
Hairs WD	0.73 ± 0.24*	55 ± 14	0.19 ± 0.07 (0.70 ± 0.06)	0.80 ± 0.07	1.47 ± 0.95
Hairs D	0.86 ± 0.21	48 ± 14*	0.23 ± 0.07 (0.71 ± 0.08)	0.80 ± 0.06	1.60 ± 0.99

Data are mean ± SD in n = 100 subvolumes (80 in the case of hairs WD) per treatment. D _eff is the average relative effective diffusion coefficient in fully saturated soil, k is average saturated permeability and ${\mathrm{\Gamma }}_p$ is the dimensionless connectivity index described in (Eqn 1). Asterisks denote statistical differences between treatments. WD, wet–dry treatment; D, dry treatment. Size of the individual subvolumes was 500 × 500 × 500 mm.