紫花苜蓿/无芒雀麦间作对草地生产性能和土壤理化特性的影响OA

To determine the optimal inter-row planting ratio of alfalfa(Medicago sativa)and smooth brome(Bromus inermis)for cultivation in the semi-arid region of Ningxia,a field study was conducted with single-crop alfalfa(CKM)and smooth brome(CKB)as controls.The treatments consisted of five different inter-row planting ratios of M.sativa(M)and B.inermis(B):3∶1(M3B1),2∶1(M2B1),1∶1(M1B1),1∶2(M1B2),and 1∶3(M1B3).The agronomic traits and nutritional quality of both species and soil nutrient contents were measured and analyzed under these different planting patterns.It was found that the 2∶1 inter-row planting ratio(M2B1)achieved the best performance in terms of yield,quality,and soil nutrient accumulation.Compared with CKM,the M2B1 treatment increased the number of alfalfa branches by 18.36%.Compared with CKB,the M2B1 treatment enhanced smooth brome plant height and leaf area by 22.40%and 37.03%,respectively.The mixed hay yield under M2B1 reached 17.70 t·ha-1,comparable to that of CKM.In terms of nutritional quality,the M2B1 treatment increased the crude protein content by 33.83%and decreased the neutral detergent fiber content by 5.12%,compared with CKB.Soil analysis revealed that the M2B1 treatment increased the soil organic matter content by 2.13%and 3.90%compared with that in CKM and CKB,respectively,and the alkaline-hydrolyzable nitrogen content by 16.53%and 37.33%,respectively.The results of a redundancy analysis indicated that mixed yield was positively correlated with soil available potassium and alkali-hydrolyzable nitrogen contents.In conclusion,the 2∶1 inter-row planting ratio of alfalfa and smooth brome in Ningxia optimized land resource utilization efficiency,productivity,and soil nutrient accumulation.