Soil microbial interactions are crucial in performing ecosystem functions. The microbial co-occurrence network could shed a new understanding of microbial functioning as affected by land management. Current studies on microbial community interactions mainly considered surface soils, thus the understanding of the microbial interactions and functions in the subsoils is still limited. We investigated soil samples from undisturbed remnant forests and disturbed vineyards in top- (0–25 cm) and subsoils (40–100 cm) in the Hunter Valley region, New South Wales, Australia. Soil microbial communities of bacteria and fungi were characterized by analyses of 16S rRNA and ITS amplicon sequencing, respectively. Land use differences caused the variances of soil properties, as resulted in the differences of microbial community composition and diversity, especially for the topsoils. Moreover, we found that agriculture activities had influenced the microbial networks for both the top- and subsoils. Widely connected bacterial networks were found in forest soils but they appeared as highly centralized clusters in vineyards for both layers. Although the interactions within those network clusters were enhanced in cropping soils, the connections between the clusters decreased or even isolated. We also characterized bacterial functions for element cycling based on their putative functions. Agricultural disturbances decreased the variability of C cycling bacteria for both surface and below layers, and reduced bacteria abundances working for C cycling in the topsoils. Additionally, soil bacterial co-occurrence network clusters were found to be correlated with microbial functions for element cycling, which demonstrated the significant influences of microbial network structure for microbial biological functions.

土壤微生物相互作用对于执行生态系统功能至关重要。微生物共生网络可以对受土地管理影响的微生物功能产生新的理解。目前对微生物群落相互作用的研究主要考虑表层土壤，因此对底土中微生物相互作用和功能的了解仍然有限。我们调查了来自澳大利亚新南威尔士州猎人谷地区未受干扰的残余森林和受干扰的葡萄园顶部（0-25 厘米）和底土（40-100 厘米）的土壤样本。细菌和真菌的土壤微生物群落分别通过 16S rRNA 和 ITS 扩增子测序分析进行表征。土地利用差异导致土壤性质的差异，导致微生物群落组成和多样性的差异，特别是对于表土。此外，我们发现农业活动影响了表层和底土的微生物网络。在森林土壤中发现了广泛连接的细菌网络，但它们在葡萄园的两层中都表现为高度集中的集群。尽管这些网络簇内的相互作用在种植土壤中得到增强，但簇之间的联系减少甚至孤立。我们还根据其假定的功能表征了元素循环的细菌功能。农业干扰降低了表层和下层 C 循环细菌的变异性，并降低了表土中 C 循环的细菌丰度。此外，发现土壤细菌共生网络簇与元素循环的微生物功能相关，