Influence of sowing amount and substrate thickness on the quality of sandy ecological grass blankets

[Objective] Under the condition of ensuring the quality of the grass blanket, the study aims to select the appropriate combination of substrate thickness and seeding rate, and achieve the coordination and unity of ecological and economic effects in grass blanket production. [Methods] Using Poa pratensis as the grass species, 12 indoor potted treatments were established, combining 3 sowing rates (15, 30, and 45 g/m2) with 4 substrate thicknesses (3, 5, 7, and 9 cm). This was done to examine the characteristics of sandy ecological grass blankets under varying conditions of sowing rates and substrate thicknesses, and to holistically assess the quality of the blanket formation. [Results] The results revealed significant variations in the quality indicators of the P . pratensis grass-based ecological blankets across different treatments. Z9/45 treatment (substrate thickness of 9 cm and sowing rate of 45 g/m2) yielded the highest plant density, aboveground biomass, and root biomass. Z3/15 treatment had the highest chlorophyll content, while Z7/45 treatment had the highest root tensile strength and vitality. Z5/45 treatment had the highest root length density, while Z9/15 treatment had the smallest leaf width and the best texture. Z9/45 treatment received the highest comprehensive score for blanket formation traits, as assessed by both variation analysis and membership function methods. [Conclusion] Z9/45 treatment of the grass blanket not only demonstrated excellent plant density, aboveground biomass, and root biomass but also exhibited superior overall performance. The optimal combination for preparing the P . pratensis grass blanket with sand-based ecology was a substrate thickness of 9 cm and a sowing rate of 45 g/m2.