紫花苜蓿与禾本科牧草混播对土壤酶活性的影响

Effects of mixed sowing of alfalfa and gramineous pasture on soil enzyme activity

摘要:

紫花苜蓿(Medicago sativa)与无芒雀麦(Bromus inermis)、草地早熟禾(Poa pratensis)、苇状羊茅(Festuca arundinace)均分别按1∶2(记作:A1、B1、C1)、1∶1(A2、B2、C2)和2∶1(A3、B3、C3)比例进行同行混播,以紫花苜蓿单播、相应禾草单播为对照,研究紫花苜蓿与不同多年生禾草混播对土壤酶活性的影响。结果表明:与苜蓿单播相比,混播提高了0~20 cm土层的土壤碱性磷酸酶、蔗糖酶活性;与禾草单播相比混播提高了0~20 cm土层脲酶活性以及20~40 cm土层的脲酶、碱性磷酸酶、蔗糖酶和过氧化氢酶活性。紫花苜蓿+无芒雀麦混播处理土壤脲酶、过氧化氢酶活性以及紫花苜蓿+苇状羊茅混播处理的碱性磷酸酶活性高于其他组合,土壤蔗糖酶活性为0~20 cm土层紫花苜蓿+苇状羊茅混播和20~40 cm土层紫花苜蓿+草地早熟禾混播处理最高。同组合不同比例处理间,0~20,20~40 cm土层A2、B3、C3处理土壤脲酶和过氧化氢酶活性最高,A1、B1、C3处理的土壤蔗糖酶最高;土壤碱性磷酸酶活性为0~20 cm土层C2处理以及20~40 cm土层C3处理高于其他比例。

Abstract:

In this experiment,alfalfa was mixed with bromus inermis,kentucky bluegrass and tall fescuesat in ratios of 1∶1 (mark as A1,B1,C1),1∶2 (mark as A2,B2,C2) and 2∶1 (mark as A3,B3,C3),respectively.Using the monoculture of alfalfa and grass species as the control,the effects of alfalfa mixed with different perennial grasses on soil enzyme activity were studied.The results showed that mixed sowing increased the activity of soil alkaline phosphatases and invertase in 0~20 cm soil layer compared with alfalfa monoculture,and increased urease activity in the top 20 cm soil layer and all enzyme activities in the 20~40 cm soil layer relative to the grass monoculture.Among all treatments,the mixed cropping of alfalfa and bromus inermis had the highest soil urease and catalase activity,while the mixture of alfalfa and tall fescuesat had the highest activity of alkaline phosphatases.Soil invertase activity was found highest in the mixture of alfalfa and tall fescuesat in the top 20 cm and in the mixture of alfalfa and kentucky bluegrass for the 20~40 cm soil layer.Among the treatments with different ratio of alfalfa to grass within the species combination,the highest soil urease and catalase activity was found in the 0~20 cm and 20~40 cm soil layers for the A2,B3 and C3 treatments,and the highest invertase activity was found in A1,B1 and C3 treated soil.The highest activity of alkaline phosphatases was found in 0~20 cm soil layer for C2 treatment and 20~40 cm soil layer for C3 treatment.