解淀粉芽孢杆菌生物有机肥防控土壤氨挥发

为了验证解淀粉芽孢杆菌生物有机肥防控农田土壤氨挥发的效果，并了解其微生物生态学机制，通过温室蔬菜大棚盆栽生菜的方式，探究在施用解淀粉芽孢杆菌生物有机肥（BB）与化肥的条件下，土壤氨挥发量、作物品质及产量、土壤微生物的变化.设置4组盆栽试验，依次为不施肥对照（CK）、100%化肥处理（C）、50% BB+50%化肥处理（B1）和100% BB处理（B2），3组处理的施氮量相同.采用动态箱法对施肥后土壤氨挥发通量进行测定.基于16S rDNA高通量测序分析，对土壤氨挥发峰值期间的细菌群落进行分析.结果发现，与C组相比，B1和B2组的氨挥发总量分别降低79.5%和84.8%；B2组生菜硝酸盐含量最低、产量最高，相对于CK和C组分别增产50.5%和12.3%；B1组生菜的维生素C含量最高，为67.6mg ·kg^-1；施用BB提高了土壤细菌群落的多样性及丰富度，特别是芽孢杆菌、硝化螺菌属相对丰度明显提升；显示出施用BB对防治空气污染和提高氮素利用率具有重要作用.

Bacillus amyloliquefaciens Biofertilizer Mitigating Soil Ammonia Volatilization

In this study, we investigated the effectiveness and microbial mechanism of Bacillus amyloliquefaciens biofertilizer on reducing ammonia volatilization in farmland soil. Pot experiments were carried out to explore the effects of B. amyloliquefaciens biofertilizer (BB) and chemical fertilizer on soil ammonia volatilization, crop yield and quality, and soil microbial community. Four fertilization strategies were tested, namely no fertilizer (CK), 100% chemical fertilizer (C), 50% BB and 50% chemical fertilizer (B1), and 100% BB (B2). The dynamic flow-through chamber method was used to determine the soil ammonia volatilization flux after fertilization. The soil bacterial community during the peak period of ammonia volatilization was analyzed using 16S rDNA high-throughput sequencing. The results showed that the amount of ammonia volatilization in B1 and B2 decreased by 79.5% and 84.8%, respectively, as compared with treatment C. B2 had the lowest nitrate content and the highest yield; the yield of B2 increased by 50.5% and 12.3% as compared to that of CK and C, respectively. B1 had the highest content of vitamin C, which was 67.6 mg ·kg^-1. The application of BB improved the diversity and richness of soil bacterial community, especially the relative abundance of Bacillus and Nitrospira. This shows that BB plays an important role in preventing air pollution and improving nitrogen utilization.