梨园不同土壤深度细菌多样性分析

【目的】通过研究梨园不同土壤深度细菌微生物群落变化情况，为梨园精准施肥及土壤微生物群落结构改良提供参考。【方法】以河北省农林科学院昌黎果树研究所孔庄试验基地梨园土壤为研究对象，通过测定不同深度土壤（5～15 cm、15～25 cm和25～35 cm）的理化性质及细菌微生物群落结构，揭示土壤理化性质和细菌变化趋势及相互关系。【结果】梨园土壤的有机质、碱解氮、速效磷和速效钾含量随着土壤深度的增加逐渐降低。不同深度土壤相同OTUs为3025个，一致性达60.00%。香农指数、辛普森指数、Chao1指数和ACE指数均随土壤深度增加逐渐降低，且各指数在处理间均无显著差异（P>0.05）。主成分（PCoA）分析发现，5～15 cm与15～25 cm的土壤细菌群落结构相似性较高，25～35 cm与5～15 cm、15～25 cm土壤群落结构均差异较大。土壤细菌门水平以变形菌门（Proteobacteria）和酸杆菌门（Acidobacteriota）为主；细菌属水平以RB41、念珠菌固体杆菌属（Candidatus Solibacter）和藓杆菌属（Bryobacter）为主；细菌种水平以大肠...

Bacterial diversity in different soil depths in pear orchard

【Objective】 By studying the changes of bacterial microbial communities in different soil depths in pear orchards, it was hoped to provide references for precise fertilization and soil microbial community structure improvement in pear orchards.【Method】 Taking the pear orchard soil in Kongzhuang Experimental Base of Changli Institute of Pomology, Hebei Academy of Agriculture and Forestry Sciences as the research object, the physical and chemical properties and bacterial microbial communities of different soil depths(5-15 cm, 15-25 cm and 25-35 cm) were measured. Revealing trends in soil physicochemical properties and bacteria at different soil depths and the relationship between them.【Result】 With the continuous increase of soil depth, the content of soil organic matter, available nitrogen, available phosphorus. There were 3025 identical OTUs in different soil depths, with a consistency of 60.00%. Shannon index, Simpson index, Chao1 index, ACE index all gradually decreased with the increase of soil depth, and there was no significant difference between the treatments of each index(P>0.05). Principal component(PCoA) analysis found that the 5-15 cm and 15-25 cm soil depths were similar in bacterial community structure, and the 25-35 cm and 5-15 cm and 15-25 cm soil depths were quite different in community structure. The phylum of soil bacteria was mainly Proteobacteria and Acidobacteriota; the bacterial genus was mainly RB41, Candidatus Solibacter, Bryobacter;Escherichia coli relative abundance was the highest at bacterial species level. Organic matter, available nitrogen, available phosphorus and available potassium all had extremely significant positive correlation with the Proteobacteria(P<0.01), and had significant negative correlation with the Crenarchaeota(P<0.05, the same below). Organic matter, available nitrogen and available phosphorus all had significant positive correlation with Shannon index.【Conclusion】 Soil depth has great impact on soil physical and chemical properties and bacterial community structure, and bacterial communities have strong correlation with soil physical and chemical factors. The distribution of bacterial communities at different soil depths of pear orchard can be used as a basis for improving bacterial community diversity.