College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
College of Environment and Safety Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
Ecotoxicol Environ Saf. 2021 Jan 1;207:111551. doi: 10.1016/j.ecoenv.2020.111551. Epub 2020 Nov 3.
Oil spills have an important threat to the ecological security and human health, for example the important oil field and coastal wetland Yellow River Delta is facing the dual problems of oil pollution and salinization. Therefore, the purpose of this study was to analyze the changes of soil microbial community and physicochemical properties, including pH value, total organic carbon (TOC), total petroleum hydrocarbons (TPHs) and electrical conductivity under the combined effect of petroleum and salinization. The soil properties results showed that the petroleum addition promoted the increase of TOC from 2.31 ± 0.59 mg/kg to 7.04 ± 0.42 mg/kg (r > 0.95, P < 0.1, R > 0.9), TPHs from 9.18 ± 0.07 mg/kg to 33.09 ± 4.61 mg/kg (r > 0.9, P < 0.05, R > 0.9) significantly. At the initial stage hydrocarbons caused the increase of soil salt content and the decrease of pH. Salt addition increased soil salt from 2.46 ± 0.13 g/kg to 15.12 ± 0.21 g/kg (r > 0.8, P > 0.1, R > 0.95), but it had no direct effect on other soil properties. It was found that the nitrate reducing bacteria Halorhodospiraceae with potential petroleum degradation ability and the anaerobic bacteria Lactobacilliceae appeared after adding crude oil. The salt tolerant bacteria Halobacilli and the stone oil degrading bacteria Immundisolidcharacter appeared in the high salt and low salt environments respectively. The aerobic bacteria Acidimicrobiaceae, Hyphomonas and the nonoil efficient Peptoccaceae disappeared in the process of salinization and oil pollution. Lactobacilliceae can ferment carbohydrate, fatty acid or ester to produce lactic acid, acetic acid and fumaric acid to provide metabolic substrate for other microorganisms. The above results showed that sensitive microorganisms were easy to be affected by pollution to indicate soil conditions, while tolerant microorganisms could potentially use oil to achieve bioremediation. The soil properties and microbial results provided data support and theoretical basis for further understanding the pollution mechanism of oil and salinization combined stress on soil.
溢油对生态安全和人类健康构成重大威胁，例如，重要的油田和沿海湿地黄河三角洲正面临着石油污染和盐渍化的双重问题。因此，本研究的目的是分析在石油和盐渍化的共同作用下，土壤微生物群落和理化性质（包括 pH 值、总有机碳（TOC）、总石油烃（TPHs）和电导率）的变化。土壤性质结果表明，石油的添加促进了 TOC 从 2.31±0.59mg/kg 增加到 7.04±0.42mg/kg（r>0.95，P<0.1，R>0.9），TPHs 从 9.18±0.07mg/kg 增加到 33.09±4.61mg/kg（r>0.9，P<0.05，R>0.9）。在初始阶段，碳氢化合物导致土壤盐分含量增加和 pH 值降低。盐的添加使土壤盐分从 2.46±0.13g/kg 增加到 15.12±0.21g/kg（r>0.8，P>0.1，R>0.95），但对其他土壤性质没有直接影响。研究发现，具有潜在石油降解能力的硝酸盐还原菌 Halorhodospiraceae 和厌氧细菌 Lactobacilliceae 在添加原油后出现。耐盐菌 Halobacilli 和石油降解菌 Immundisolidcharacter 分别出现在高盐和低盐环境中。好氧菌 Acidimicrobiaceae、Hyphomonas 和非油高效菌 Peptoccaceae 在盐化和石油污染过程中消失。Lactobacilliceae 可以发酵碳水化合物、脂肪酸或酯类，产生乳酸、乙酸和富马酸，为其他微生物提供代谢底物。上述结果表明，敏感微生物容易受到污染的影响，从而指示土壤状况，而耐受微生物可能利用石油实现生物修复。土壤性质和微生物结果为进一步了解石油和盐渍化联合胁迫对土壤的污染机制提供了数据支持和理论依据。
