International Research Center in Critical Raw Materials for Advanced Industrial Technologies (ICCRAM), University of Burgos, Centro de I+D+I. Plaza Misael Bañuelos s/n. 09001, Burgos, Spain; Research Group in Composting (UBUCOMP), University of Burgos, Faculty of Sciences, Plaza Misael Bañuelos s/n, 09001, Burgos, Spain.
International Research Center in Critical Raw Materials for Advanced Industrial Technologies (ICCRAM), University of Burgos, Centro de I+D+I. Plaza Misael Bañuelos s/n. 09001, Burgos, Spain.
Chemosphere. 2022 Nov;307(Pt 1):135638. doi: 10.1016/j.chemosphere.2022.135638. Epub 2022 Jul 8.
In the present work, the operational conditions for improving the degradation rates of Total Petroleum Hydrocarbons (TPHs) in contaminated soil from a machinery park were optimized at a microcosms scale along a 90-days incubation period. In this study, bioremediation strategies and an organic amendment have been tested to verify the remediation of soil contaminated with different hydrocarbons, mineral oils, and heavy metals. Specifically, designed biostimulation and bioaugmentation strategies were compared with and without adding vermicompost. The polluted soil harboring multiple contaminants, partially attenuated for years, was used. The initial profile showed enrichment in heavy linear alkanes, suggesting a previous moderate weathering. The application of vermicompost increased five and two times the amounts of available phosphorus (P) and exchangeable potassium (K), respectively, as a direct consequence of the organic amendment addition. The microbial activity increased due to soil acidification, which influenced the solubility of P and other micronutrients. It also impacted the predominance and variability of the different microbial groups and the incubation, as reflected by phospholipid fatty acid (PLFA) results. An increase in the alkaline phosphatases and proteases linked to bacterial growth was displayed. This stimulation of microbial metabolism correlated with the degradation rates since TPHs degradation' efficiency after vermicompost addition reached 32.5% and 34.4% of the initial hydrocarbon levels for biostimulation and bioaugmentation, respectively. Although Polycyclic Aromatic Hydrocarbons (PAHs) were less abundant in this soil, results also decreased, especially for the most abundant, the phenanthrene. Despite improving the degradation rates, results revealed that recalcitrant and hydrophobic petroleum compounds remained unchanged, indicating that mobility, linked to bioavailability, probably represents the limiting step for further soil recovery.
在本工作中，通过 90 天的孵化期，在微宇宙规模上优化了提高机械园区污染土壤中总石油烃 (TPH) 降解率的操作条件。在这项研究中，测试了生物修复策略和有机添加剂，以验证不同烃类、矿物油和重金属污染土壤的修复效果。具体来说，比较了设计的生物刺激和生物增强策略，同时添加和不添加蚯蚓粪。使用了多年来部分衰减的多污染物污染土壤。初始特征表明存在富含重线性烷烃，表明先前存在中度风化。添加蚯蚓粪直接增加了有效磷 (P) 和可交换钾 (K) 的含量，分别增加了五倍和两倍。由于有机添加剂的添加，土壤酸化增加了微生物活性，这影响了 P 和其他微量元素的溶解度。它还影响了不同微生物群体的优势和变异性以及孵化过程，如磷脂脂肪酸 (PLFA) 结果所反映的那样。显示出与细菌生长相关的碱性磷酸酶和蛋白酶的增加。这种微生物代谢的刺激与降解率相关，因为添加蚯蚓粪后生物刺激和生物增强的 TPH 降解效率分别达到初始烃水平的 32.5%和 34.4%。尽管这种土壤中多环芳烃 (PAHs) 的丰度较低，但结果也有所下降，特别是对最丰富的菲。尽管提高了降解率，但结果表明，顽固和疏水性石油化合物仍未改变，表明与生物利用度相关的迁移可能是进一步土壤恢复的限制步骤。
