Production performance and stability of mixed forage grasslands improved by planting proportion and mode in Horqin sandy land, China

Sowing mixed artificial grassland can aid grassland husbandry and restoration. However, the optimal mix and sowing mode for forage grass and legume grass in Horqin Sandy Land, China, remains unidentified. In this study, grassland production performance and stability were investigated using three mixed-sowing modes (peer-mixed, cross-mixed, and intercropping) and five mixed sowing ratios (awnless brome: alfalfa at 1:0, 1:1, 3:2, 2:1, 5:2, 3:1, 0:1). The cross-mixed sowing mode with a 2:1 ratio had the highest yields and greatest total nitrogen accumulation. All treatments had a land equivalent ratio ≥ 1, and C3 (cross-mixed at a 2:1 ratio, 2021 and 2022) had the largest value. The C3 treatment had the highest LERN, which was not significantly different from those of C1 (cross-mixed at a 1:1 ratio), C2 (cross-mixed at a 3:2 ratio), I2 (intercropping at a 3:2 ratio), and I3 (intercropping at a 2:1 ratio) treatments in 2021 and 2022. The sustainable yield index of C3 was significantly higher than those of the other treatments, excluding C2 (P < 0.05). TOPSIS evaluation indicated that cross-mixing at a 2:1 ratio is ideal and represents a crucial intercropping technique for establishing efficient and sustainable grassland ecosystems, which could further facilitate animal husbandry development.