Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China.
Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, People's Republic of China.
Microb Ecol. 2023 Nov;86(4):2436-2446. doi: 10.1007/s00248-023-02245-3. Epub 2023 Jun 6.
Petroleum contamination is a severe threat to the soil environment. Previous studies have demonstrated that petroleum degradation efficiency is promoted by enhancing soil moisture content (MC). However, the effects of MC on soil microbial ecological functions during bioremediation remain unclear. Here, we investigated the impacts of 5% and 15% of moisture contents on petroleum degradation, soil microbial structures and functions, and the related genes using high-throughput sequencing and gene function prediction. Results indicated that petroleum biodegradation efficiency was increased by 8.06% in the soils with 15% MC when compared to that with 5% of MC. The complexity and stability of soil microbial community structures with 15% MC were higher than those in the soils with 5% MC when hydrocarbon-degrading bacterial flora (HDBF) were inoculated into the soils. Fifteen percent of moisture content strengthened the interaction of the bacterial community network and reduced the loss of some key bacteria species including Mycobacterium, Sphingomonas, and Gemmatimonas. Some downregulated gene pathways relating to bioaugmentation were enhanced in the soils with 15% MC. The results suggested that the dynamic balances of microbial communities and the metabolic interactions by 15% MC treatment are the driving forces for the enhancement of bioremediation in petroleum-contaminated soil.
石油污染对土壤环境构成严重威胁。以往的研究表明，提高土壤水分含量（MC）可以促进石油降解效率。然而，MC 对生物修复过程中土壤微生物生态功能的影响尚不清楚。本研究采用高通量测序和基因功能预测技术，调查了 5%和 15%两种 MC 对石油降解、土壤微生物结构和功能及相关基因的影响。结果表明，与 5% MC 相比，15% MC 可使石油生物降解效率提高 8.06%。在向土壤接种烃类降解细菌菌群（HDBF）时，15% MC 土壤中微生物群落结构的复杂性和稳定性高于 5% MC 土壤。15%的水分含量增强了细菌群落网络的相互作用，减少了一些关键细菌物种的流失，包括分枝杆菌、鞘氨醇单胞菌和芽单胞菌。一些与生物强化相关的下调基因途径在 15% MC 土壤中得到了增强。结果表明，微生物群落的动态平衡和 15% MC 处理的代谢相互作用是增强石油污染土壤生物修复的驱动力。
