Table 1: GR characteristics.

Characteristics GR1 GR2
Location (Latitude, Longitude) 40.770425, 14.789443
Area (m2) 2.5
Slope (°) 1
Overall thickness (mm) 150
Vegetation type Mesembryanthemum
Substrate depth (mm) 100
Substrate material Peat and zeolite
Porosity (%) 94
Drainage (mm) 50
Drainage material Expanded clay Commercial plastic trays with exclay
Retention capacity (l/m2)
Drainage
6.7 8.1