不同播量一年生苜蓿与燕麦混播对草地生产性能和营养价值的影响OA

To investigate the optimal seeding rates of annual Medicago scutellata and Avena sativa mixed sowing suitable for the irrigation areas in Northwest China and their effects on grassland productivity and nutritional value,a field trial was conducted in the Yellow River diversion irrigation area of Ningxia in 2024.A.sativa seeding rate was fixed at 120.0 kg/hm2 and were mixed with six different seeding rates for annual M.scutellata(12.0,18.0,24.0,30.0,36.0 and 42.0 kg/hm2,designated as IM1,IM2,IM3,IM4,IM5 and IM6).Monoculture of annual M.scutellata(SM,30.0 kg/hm2)and monoculture of A.sativa(SO,180.0 kg/hm2)served as controls.Grassland productivity,nutritional quality,and interspecific relationships were systematically determed through two successive crop cycles of sowing and harvesting.The results indicated that:1)Mixed cropping significantly enhanced grassland productivity.Among all the treatments,IM4 performed the best,with the highest total dry matter production(20.93 t/hm2)across two harvests,representing a 24.2％increase over A.sativa monoculture and a 44.7％rise in crude protein yield(2.36 t/hm2).This treatment achieved land equivalency ratio of 1.33,and had 33％increase in land utilization efficiency.2)While the IM6 treatment had the highest crude protein content and relative feeding value(25.3％and 12.6％higher than monoculture respectively),the IM4 treatment achieved a better balance between yield(20.93 t/hm2)and quality(11.48％crude protein content).In summary,mixed sowting of 30.0 kg/hm2 of annual M.scutellata with 120.0 kg/hm2 A.sativa can synergistically achieve a high yield and superior quality while efficiently utilization land resources.This approach provides a theoretical foundation and practical planting solution for establishing ecological agro-pastoral systems in arid irrigated areas.