Table 1.

Experiment cases with geometrical parameters. a is frontal area per unit volume and is defined as $a=\frac{1}{v}{\sum }_{n=1}^{\infty }{A}_i$ where $A_i$ is a frontal area of individual cylinders and N is the number of cylinders and porosity is calculated by $\varphi =1-N{(\frac{d}{D})}^2$.

Case no	Frontal area (a) (${\text{m}}^{-1}$)	Patch diameter (D) (mm)	aD	Root diameter (d) (mm)	Porosity ($\varphi \%$)
1	N/A	26	N/A	N/A	0
2	107.6	26	2.8	6.35	47.1
3	80.7	26	2.1	4.76	70.4
4	53.82	26	1.4	3.17	86.5

Porosity is the complement of solidity which is the ratio between volume occupied by the roots to the volume occupied by water for confined space below the water surface⁶⁴.