堆肥可以减少石油污染土壤中的石油碳氢化合物,然而,堆肥系统中不同碳链结构的石油烃的微生物降解机理和生物降解调节方法尚未研究。本研究分析了C≤16和C>16时石油烃总浓度的变化,应用随机森林模型鉴定了在生物质改良堆肥中降解具有特定结构的石油烃组分的关键微生物。通过构建“环境因素-关键微生物-总石油烃”的影响路径,提出了不同碳链结构石油烃生物降解的调控方法。结果表明,堆肥使石油烃中C≤16组分和C>16组分的降解率分别提高了67.88%和61.87%,分别。微生物结果分析表明,C≤16级降解菌在堆肥加热阶段具有降解优势,而C>16的部分在冷却阶段降解更好。此外,特异性降解C>16组分的微生物与总氮和硝酸盐氮显著相关。C≤16馏分的生物降解受有机物调节,水分含量,和温度。通过调节46种关键微生物的代谢潜力,沼液改性堆肥系统可有效去除土壤中具有不同碳链结构的石油烃。这项研究赋予了他们预期的重要性,以达到用废物处理废物并促进土壤利用和污染修复的目的。
Composting can decrease petroleum hydrocarbons in petroleum contaminated soils, however the microbial degradation mechanisms and regulating method for biodegradation of petroleum hydrocarbons with different carbon chain structures in the composting system have not yet been investigated. This study analyzed variations of total petroleum hydrocarbon concentrations with C ≤ 16 and C > 16, Random Forest model was applied to identify the key microorganisms for degrading the petroleum hydrocarbon components with specific structure in biomass-amended composting. Regulating method for biodegradation of petroleum hydrocarbons with different carbon chain structures was proposed by constructing the influence paths of \"environmental factors-key microorganisms- total petroleum hydrocarbons\". The results showed that composting improved the degradation rate of C ≤ 16 fraction and C > 16 fraction of petroleum hydrocarbons by 67.88 % and 61.87 %, respectively. Analysis of the microbial results showed that the degrading bacteria of the C ≤ 16 fraction had degradation advantages in the heating phase of the compost, while the C > 16 fraction degraded better in the cooling phase. Moreover, microorganisms that specifically degraded C > 16 fractions were significantly associated with total nitrogen and nitrate nitrogen. The biodegradation of C ≤ 16 fraction was regulated by organic matter, moisture content, and temperature. The composting system modified by biogas slurry was effective in removing of petroleum hydrocarbons with different carbon chain structures in soil by regulating the metabolic potential of the 46 key microorganisms. This study given their expected importance to achieve the purpose of treating waste with waste and contributing to soil utilization as well as pollution remediation.