有机肥施用对植烟土壤氮素矿化及土壤酶和微生物群落的影响

为探索不同有机肥对植烟土壤氮素矿化及土壤微生态的影响。在等氮(100 mg/kg)投入和30℃条件下对施入不同有机肥(植物源有机肥、芝麻饼肥、生物质炭有机肥)的土壤进行室内培养，分析不同时期土壤NO3–-N和NH4+-N含量、土壤酶活性及细菌群落多样性的变化。结果表明：施用不同有机肥均可提高土壤矿质氮含量，在培养前期以饼肥矿化量最高，矿化速率最快，而后期为生物质炭有机肥处理的氮素矿化量、矿化速率高于其他处理；施用生物质炭有机肥、植物源有机肥均可显著提高土壤脲酶、硝酸还原酶活性，芝麻饼肥对蛋白酶、蔗糖酶活性有显著的提升作用；相较不施有机肥处理，添加不同有机肥的土壤细菌多样性明显提升。优势菌门为变形菌门、酸杆菌门、拟杆菌门、浮霉菌门，优势菌属为Sphingomonas、RB41,Sphingomonas在不施有机肥处理中最高，RB41在生物质炭有机肥处理中最高。Sphingomonas与蔗糖酶活性呈正相关关系，与脲酶、硝酸还原酶均呈负相关关系；PCA分析显示，生物质炭有机肥处理的细菌群落结构与其他处理相比差异较大。施用芝麻饼肥有利于促进早期氮素矿化，提高矿化量，而生物质炭有机肥后期矿化量较...

Effects of Organic Fertilizers on Nitrogen Mineralization, Soil Enzyme Activities and Microbial Communities in Tobacco-planting Soil

In order to explore the effects of different organic fertilizers on nitrogen mineralization and soil microecology in tobacco planting soil. Soil with different organic fertilizers(plant organic fertilizer, sesame cake fertilizer, biochar organic fertilizer)were cultured in laboratory to analyze the changes of nitrate nitrogen and ammonium nitrogen content, soil enzyme activity and bacterial community diversity in different periods. The results show that application of different organic fertilizers could increase the soil mineral nitrogen content.In the early stage of culture, the highest mineralization amount and the fastest mineralization rate of cake fertilizer were found,while in the later stage, the nitrogen mineralization amount and the mineralization rate of biochar organic fertilizer were higher than other treatments.Application of biochar organic fertilizer and plant-derived organic fertilizer could significantly improve the activities of soil urease and nitrate reductase,and sesame cake fertilizer could significantly improve the activities of protease and sucrase.Compared with no organic fertilizer treatment,soil bacterial diversity increased significantly with different organic fertilizers.The dominant bacteria genera were Proteobacteria,Acidobacteria, Bacteroidetes and pontosiformis.The dominant bacteria genera were Sphingomonas and RB41.Sphingomonas was the highest in the treatment without organic fertilizer,while RB41 was the highest in the treatment of biocarbon organic fertilizer.Sphingomonas was positively correlated with sucrase activity,and negatively correlated with urease and nitrate reductase.PCA analysis showed that the bacterial community structure of biochar organic fertilizer treatment was significantly different from that of other treatments. The application of sesame cake fertilizer can promote the early nitrogen mineralization and increase the amount of mineralization, and the mineralization rate of biochar organic fertilizer is larger and faster in the late stage,and the diversity and richness of soil bacteria are also the highest.