Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy.
Department of Biotechnology, University of Verona, Strada Le Grazie 15, 37134 Verona, Italy.
J Environ Manage. 2015 Apr 15;153:121-31. doi: 10.1016/j.jenvman.2015.02.007. Epub 2015 Feb 15.
In this work, the natural attenuation strategy (no soil amendments done) was compared with two different bioremediation approaches, namely bioaugmentation through soil inoculation with a suspension of Trichoderma sp. mycelium and biostimulation by soil addition with a microbial growth promoting formulation, in order to verify the effectiveness of these methods in terms of degradation efficiency towards toxic hydrocarbons, with particular attention to the high molecular weight (HMW) fraction, in a forest area impacted by recent wildfire in Northern Italy. The area under investigation, divided into three parcels, was monitored to figure out the dynamics of decay in soil concentration of C₁₂₋₄₀ hydrocarbons (including isoalkanes, cycloalkanes, alkyl-benzenes and alkyl-naphthalenes besides PAHs) and low molecular weight (LMW) PAHs, following the adoption of the foregoing different remediation strategies. Soil hydrocarbonoclastic potential was even checked by characterizing the autochthonous microbial cenoses. Field experiments proved that the best performance in the abatement of HMW hydrocarbons was reached 60 days after soil treatment through the biostimulation protocol, when about 70% of the initial concentration of HMW hydrocarbons was depleted. Within the same time, about 55% degradation was obtained with the bioaugmentation protocol, whilst natural attenuation allowed only a 45% removal of the starting C12-40 hydrocarbon fraction. Therefore, biostimulation seems to significantly reduce the time required for the remediation, most likely because of the enhancement of microbial degradation through the improvement of nutrient balance in the burned soil.
在这项工作中，自然衰减策略（未进行土壤改良）与两种不同的生物修复方法进行了比较，即通过接种木霉菌丝悬浮液进行生物增强和通过添加微生物生长促进剂进行生物刺激，以验证这些方法在降解有毒碳氢化合物方面的有效性，特别是对高分子量（HMW）馏分的有效性，该方法是在意大利北部受近期野火影响的森林地区进行的。研究区域被分为三个地块进行监测，以了解在采用上述不同修复策略后土壤中 C₁₂₋₄₀ 碳氢化合物（包括异烷烃、环烷烃、烷基苯和烷基萘以及多环芳烃）和低分子量（LMW）多环芳烃浓度的衰减动态。通过表征土著微生物菌群，甚至检查了土壤碳氢化合物的分解潜力。田间实验证明，通过生物刺激方案在 60 天后处理土壤时，在 HMW 碳氢化合物的去除方面表现最佳，此时约 70%的初始 HMW 碳氢化合物浓度被耗尽。在同一时间内，通过生物增强方案获得了约 55%的降解，而自然衰减仅允许初始 C12-40 碳氢化合物馏分去除 45%。因此，生物刺激似乎显著缩短了修复所需的时间，这很可能是因为通过改善燃烧土壤中的养分平衡来增强微生物降解。
