Abstract: This research studied the effect of carpet mesh implantation on carpet mesh hybrid turf performance and soil-bed stability. The grass species used was perennial ryegrass (Lolium perenne cv. Neruda 1BT). Treatments comprised a control with no carpet mesh and comparison of three carpet mesh types (A, 15 mm×15 mm mesh with no backing; B, 30×30 mm mesh with backing; C, 20 mm×12.5 mm mesh with backing) implanted below the soil surface, in foam boxes 35 cm×23 cm in area and 19 cm deep, and filled with pure sand predominantly 0.1-0.5 mm particle size. Measurements included aboveground and underground biomass, root morphological parameters (root length, root surface area, root volume and root vigour), and testing of the soil-bed stability of the hybrid turf using a direct shear test. It was found that carpet implantation significantly decreased turfgrass performance, with decline in color, NDVI and density. The density decline with implantation of the three carpet types at day 116 from planting was 20.8%, 8.7% and 14.7% at the 116th day, for carpet mesh types A, B and C, respectively. However, carpet types with mat(B and C) increased the turfgrass uniformity. Furthermore, compared with the control, carpet implantation decreased the underground biomass, root length, root surface area and root volume, and also compromised root vigour, both above and beneath the carpet. Carpet implantation did increase the turf shear strength (by 51.9%, 162.7% and 134.6%, for mesh types A, B, and C, respectively), surface firmness (by 34.6%, 32.8% and 45.8%, for mesh types A, B, and C, respectively), and increased cohesion compared to the control. In summary, in the artificial-natural hybrid turf, the carpet implantation inhibited the growth of roots, which compromised the aboveground growth of the turf grass and turf performance. Carpet implantation, especially carpet with mat, did increase the mechanical stability of the hybrid turf.

Key words: carpet hybrid turf, turf performance quality, root parameters, root vigour, shear strength