Soil microorganisms play a key role in soil physical structure. Soil microbial community structure and functions are in turn affected by soil aggregation or degradation. The objectives of this study were to determine the impact of (1) soil aggregate-size distribution and (2) soil compaction on bacterial community richness and structure under three intensive potato (Solanum tuberosum) cropping systems. In June and July 2014, soil samples were collected at a depth of 0-20 cm from 16 sites in Quebec, Canada. The samples were analyzed for aggregate-size distribution, particle-size distribution, total carbon, total nitrogen, total sulfur, oxalate-extractable potassium and phosphorus, gravimetric moisture content, pH and degree of compactness (DC). Soil bacterial community diversity was assessed by using the high-throughput sequencing Illumina MiSeq platform to target the V6-V8 region of bacterial 16S rRNA gene. Bacterial alpha diversity and community structure were found to be affected by cropping systems. Faith's phylogenetic diversity index and bacterial richness increased with increasing proportions of the 1–0.5 mm and 2–1 mm aggregate-size fractions and micro-aggregates in soils. Redundancy analysis revealed a strong correlation between soil bacterial community structure and soil aggregate-size distribution. Eight of the 27 dominant bacterial classes had a significant relationship with aggregate size fractions >2 mm, 1- 0.5 mm and < 0.1 mm. In addition, the degree of soil compaction had a significant effect on soil bacterial community structure, with 70% of the dominant classes showing greater relative abundance in the moderate and high DC groups than in the low DC group. This research provided a benchmark for bacterial community structure in potato agroecosystems as impacted by soil aggregation and compaction.

土壤微生物在土壤物理结构中起关键作用。土壤微生物群落结构和功能反过来又受到土壤聚集或退化的影响。本研究的目的是确定（1）土壤团聚体大小分布和（2）土壤压实对三种集约化马铃薯（Solanum tuberosum）下细菌群落丰富度和结构的影响。) 种植系统。2014 年 6 月和 7 月，在加拿大魁北克省的 16 个地点采集了 0-20 厘米深度的土壤样品。分析样品的聚集体粒度分布、粒度分布、总碳、总氮、总硫、草酸盐可萃取的钾和磷、重量含水量、pH 值和密实度 (DC)。通过使用高通量测序 Illumina MiSeq 平台靶向细菌 16S rRNA 基因的 V6-V8 区域来评估土壤细菌群落多样性。发现细菌阿尔法多样性和群落结构受到种植系统的影响。Faith 的系统发育多样性指数和细菌丰富度随着土壤中 1-0.5 毫米和 2-1 毫米团聚体大小部分和微团聚体比例的增加而增加。冗余分析揭示了土壤细菌群落结构与土壤团聚体大小分布之间的强相关性。27 种主要细菌类别中的 8 种与 >2 毫米、1-0.5 毫米和 < 0.1 毫米的聚集体大小分数有显着关系。此外，土壤压实程度对土壤细菌群落结构有显着影响，70%的优势类在中高DC组中的相对丰度高于低DC组。这项研究为马铃薯农业生态系统中受土壤聚集和压实影响的细菌群落结构提供了基准。5 毫米和 < 0.1 毫米。此外，土壤压实程度对土壤细菌群落结构有显着影响，70%的优势类在中高DC组中的相对丰度高于低DC组。这项研究为马铃薯农业生态系统中受土壤聚集和压实影响的细菌群落结构提供了基准。5 毫米和 < 0.1 毫米。此外，土壤压实程度对土壤细菌群落结构有显着影响，70%的优势类在中高DC组中的相对丰度高于低DC组。这项研究为马铃薯农业生态系统中受土壤聚集和压实影响的细菌群落结构提供了基准。