Shen Qihui, Fu Wei, Chen Baodong, Zhang Xuemeng, Xing Shuping, Ji Chuning, Zhang Xin
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, China.
University of Chinese Academy of Sciences, Beijing, China.
Front Microbiol. 2023 Mar 6;14:1143742. doi: 10.3389/fmicb.2023.1143742. eCollection 2023.
Both polycyclic aromatic hydrocarbons (PAHs) and potentially toxic elements (PTEs) of coking industries impose negative effects on the stability of soil ecosystem. Soil microbes are regarded as an essential moderator of biochemical processes and soil remediation, while their responses to PAHs-PTEs combined contamination are largely unknown. In the present study, soil microbial diversity and community composition in the typical coking plant under the chronic co-exposure of PAHs and PTEs were investigated and microbial interaction networks were built to reveal microbial co-occurrence patterns. The results indicated that the concentrations of PAHs in the soil inside the coking plant were significantly higher than those outside the plant. The mean concentration of ∑16PAHs was 2894.4 ng·g, which is 5.58 times higher than that outside the plant. The average Hg concentration inside the coking plant was 22 times higher than the background value of Hebei province. The soil fungal community inside the coking plant showed lower richness compared with that of outside community, and there are significant difference in the bacterial and fungal community composition between inside and outside of coking plant ( < 0.01). Predicted contribution of different environmental factors to each dominant species based on random forest identified 20 and 25 biomarkers in bacteria and fungi, respectively, that were highly sensitive to coking plant soil in operation, such as . Bacterial and fungal communities were shaped by the soil chemical properties (pH), PTEs (Hg), and PAHs together in the coking plant soils. Furthermore, the bacterial and fungal interaction patterns were investigated separately or jointly by intradomain and interdomain networks. Competition is the main strategy based on the co-exclusion pattern in fungal community, and the competitive relationship inside the coking plant is more complex than that outside the plant. In contrast, cooperation is the dominant strategy in bacterial networks based on the co-occurrence pattern. The present study provided insights into microbial response strategies and the interactions between bacteria and fungi under long-term combined contamination.
焦化行业的多环芳烃（PAHs）和潜在有毒元素（PTEs）都会对土壤生态系统的稳定性产生负面影响。土壤微生物被视为生化过程和土壤修复的重要调节者，然而它们对PAHs - PTEs复合污染的响应在很大程度上尚不清楚。在本研究中，调查了典型焦化厂在PAHs和PTEs长期共同暴露下的土壤微生物多样性和群落组成，并构建了微生物相互作用网络以揭示微生物共生模式。结果表明，焦化厂内土壤中PAHs的浓度显著高于厂外。∑16PAHs的平均浓度为2894.4 ng·g，比厂外高5.58倍。焦化厂内汞的平均浓度比河北省背景值高22倍。焦化厂内土壤真菌群落的丰富度低于厂外群落，且焦化厂内外细菌和真菌群落组成存在显著差异（<0.01）。基于随机森林预测不同环境因素对各优势物种的贡献，分别在细菌和真菌中鉴定出20个和25个生物标志物，它们对焦化厂运行中的土壤高度敏感，例如 。在焦化厂土壤中，细菌和真菌群落共同受土壤化学性质（pH）、PTEs（汞）和PAHs的影响。此外，通过域内和域间网络分别或联合研究了细菌和真菌的相互作用模式。基于真菌群落中的共排斥模式，竞争是主要策略，且焦化厂内的竞争关系比厂外更复杂。相比之下，基于共生模式合作是细菌网络中的主导策略。本研究为长期复合污染下微生物的响应策略以及细菌与真菌之间的相互作用提供了见解。
