Effects of reseeded native forage species on soil water holding capacity and vegetation biomass in a desert steppe

To explore the impact of reseeded native species on vegetation restoration in degraded grasslands we assessed the effects of Agropyron mongolicum monoculture (M), Lespedeza potaninii monoculture (N), A. mongolicum × L. potaniniimixture (MN), A. mongolicum × Astragalus adsurgens mixture (MS), A. mongolicum × A. melilotoides mixture (MX), and grazing grassland (FM) on soil water holding capacity-related parameters, as well as aboveground and underground biomass in Yanchi County, Ningxia. The results showed that: 1) Soil water holding capacity differed among different treatments (M > MS > MN > MX > N > FM). 2) All reseeded treatments led to higher underground biomass than FM, and underground biomass was higher under M than N, while aboveground biomass varied according to MS > MX, M, MN > N > FM. 3) Redundancy analysis (RDA) showed that underground and aboveground biomass were positively and significantly correlated with all the soil water holding capacity-related parameters. In conclusion, this study demonstrated that both monocultures, or mixed reseeding, of A. mongolicum could improve soil water holding capacity and accelerate vegetation restoration due to its high biomass. Therefore, plants with high biomasses should be considered in future restoration plans of degraded grassland.