轮作方式对土壤微生物量及酶活性的影响

Effect of Different Crop Rotation Methods on Soil Microbial Biomass and Enzyme Activity

为了探究不同轮作模式对阴山北麓土壤微生物量和土壤酶活性的影响,筛选适合阴山北麓的轮作模式,试验设计了6种轮作模式、3种连作处理及休闲,共10个处理,研究轮作对土壤生物学性状的影响。结果表明:2015年,轮作处理的土壤微生物量碳含量均显著高于较连作处理,且S2、S6、S4轮作模式较好,而2016年以S2、S3、S4模式较好;微生物量氮的变化2015年以S1、S4模式较好,而2016年以S4模式下的土壤微生物量氮含量显著高于其他处理(P<0.05)。土壤过氧化氢酶活性的变化表现为2016年均低于2015年,且2015年以S2、S4、S5模式较好,2016年以S3、S4、S5模式表现较好;土壤脲酶和蔗糖酶活性的变化在2015年均以S1、S2、S4模式较好,而2016年以S4、S5模式好,且较2015年高,脲酶活性提高了24.53%、23.30%,蔗糖酶活性提高了21.23%、19.29%。2015年土壤微生物量的变化与脲酶活性呈显著相关,2016年土壤微生物量变化与土壤酶活性的相关性不显著。本试验中得出燕麦苜蓿混作(1年)、苜蓿(1年)、马铃薯(3年)种植模式能提高土壤微生物量及土壤酶活性。

To study the effect of different rotation methods on soil microbial biomass and enzyme activity and screen out the optimum rotation method in the north of Yin Mountain, we conducted an experiment consisted of 10 treatments： 6 rotation patterns, 3 continuous cropping and fallowing, and studied the effect of rotation onsoil biological character. The results showed that the soil microbial biomass C content of rotation treatment wassignificantly higher than that of continuous cropping in 2015, and S2, S6 and S4 were better rotation methods,while S2, S3 and S4 were better rotation methods in 2016. S1 and S4 increased soil microbial biomass Ncontent in 2015, while S4 increased soil microbial biomass N content remarkably in 2016（P0.05）. Thecatalase activity of all treatments in 2016 was lower than that in 2015, and that of S2、S4、S5 were higher in2015, while that of S3、S4、S5 were higher in 2016; soil urease and sucrase activity of S1, S2 and S4 increasedin 2015, and that of S4, S5 were higher in 2016 than that in 2015, urease activity increased by 24.53% and 23.30%, sucrase activity increased by 21.23% and 19.29%. Soil microbial biomass was significantly correlated with urease activity in 2015, but its correlation with soil enzyme activity was not significant in 2016. In conclusion, soil microbial biomass and soil enzyme activity could be increased by the crop rotation of oats-alfalfa intercropping 1 year, alfalfa 1 year and potato 3 years.