增碳减氮对植烟土壤微生物的影响

为探究不同增碳减氮措施对植烟土壤养分及微生物群落结构的影响，以云烟116为研究对象，设置常规施肥(CF)和3个增碳减氮处理[常规施肥减氮10%，分别加施菇渣有机肥750kg/hm²(MO)、高碳基肥600kg/hm²(HB)、生物有机肥750 kg/hm²(BO)]，测定其土壤碳氮养分及微生物群落结构。结果表明，MO处理土壤全碳和有机质含量较常规施肥CF分别显著增加了23.62%和25.05%；与CF相比，MO处理酸杆菌门、绿弯菌门两个优势菌门相对丰度更高，慢生根瘤菌属(Bradyrhizobium)相对丰度也明显高于其他处理；HB处理上述菌群相对丰度仅次于MO处理，BO处理上述菌群相对丰度最低，而镰刀菌属、腐质霉属等致病菌属在HB处理中相对丰度最低。研究表明，菇渣有机肥配合减氮措施在促进土壤碳、氮养分释放，改善土壤微生物群落结构，提升养分利用率方面效果最佳。

Effects of Different Measures of Increasing Carbon and Decreasing Nitrogen on Soil Microbes in Tobacco Planting Fields

In order to explore the effects of different carbon-increasing and nitrogen-reducing measures on soil nutrients and microbial community structure of tobacco planting fields, taking flue-cured tobacco Yunyan 116 as the research object, conventional fertilization (CF) and 3 carbon-increasing and nitrogen-reducing treatments[On the basis of conventional fertilization, reduce nitrogen by 10% and add mushroom residue organic fertilizer 750 kg/hm² (MO), high carbon base fertilizer 600 kg/hm² (HB), and biological organic fertilizer 750 kg/hm² (BO)] were conducted, and the soil carbon and nitrogen nutrients and microbial community structure were determined. The results showed that compared with the conventional fertilization CF, the contents of total carbon and organic matter in the soil treated with MO were significantly increased by 23.62% and 25.05%, respectively; The relative abundance of the two dominant bacterial phyla, Acidobacteria and Chloroflexi, was higher in MO treatment, and the relative abundance of Bradyrhizobium was also significantly higher than that in other treatments. The relative abundance of the above bacterial groups in the HB treatment was just lower than the MO treatment, and the relative abundance of the above bacterial groups in the BO treatment was the lowest. The relative abundance of HB treatment was the lowest among pathogenic bacteria such as Humicola and Fusarium. The results from this study have shown that mushroom residue organic fertilizer combined with nitrogen reduction measures has the best effect in promoting the release of soil carbon and nitrogen nutrients, improving soil microbial community structure, and improving nutrient utilization.