Soil erosion effectively alleviated by Miscanthus sacchariflorus, a potential candidate for land deterioration improvement

Abstract

Plants can reduce runoff and improve soil properties in erosion-prone areas, thereby enhancing resistance to erosion. The main goal of this research was to identify the effects of planting density on the growth and soil fixation ability of Miscanthus sacchariflorus, which is a candidate for application in soil conservation. In this study, four planting densities (low density (I, 70 × 70 cm, row spacing × plant spacing), medium density (II, 50 × 50 cm), high density (III, 30 × 30 cm), and extremely high density (IV, 15 × 15 cm)) were set and plant growth, root architecture and soil erosion resistance were measured. The results showed that tiller number, leaf length, and biomass decreased with increased planting density. Root length and surface area per plant of fibrous roots and rhizomes were significantly (P < 0.05) decreased under density IV relative to density I, indicating that higher densities inhibited the per plant growth of M. sacchariflorus. However, the vegetation coverage and the density of root mass, length (RLD), surface area (RSAD), and volume per unit soil volume of M. sacchariflorus showed opposite trends. Additionally, the water stability and soil anti-erodibility from density III were significantly (P < 0.05) higher than those of other planting densities. Furthermore, correlation analysis showed that the RLD and RSAD of fibrous roots were the most important factors for erosion resistance of the soil. Overall, the density III may be optimal for M. sacchariflorus seedlings planted to alleviate soil erosion and this species may be a suitable and ecological candidate for soil conservation.