School of Environmental Studies, China University of Geosciences, NO. 68 Jincheng Street, East Lake High-Tech Development Zone, Wuhan, 430074, People's Republic of China.
Institute of Karst Geology, Chinese Academy of Geological Sciences / Key Laboratory of Karst Dynamics, MNR and GZAR, Guilin, 541004, People's Republic of China.
Environ Sci Pollut Res Int. 2020 Jun;27(18):22780-22794. doi: 10.1007/s11356-020-08723-2. Epub 2020 Apr 22.
A rare super-large fractured karst aquifer located in Zibo city, Shandong Province of Northern China was polluted by petroleum hydrocarbons from a petrochemical company. Over the last 30 years, it has been the focus of several remediation efforts. In this study, the contamination and natural attenuation characteristics of the petroleum hydrocarbons were elucidated using hydrogeochemical indicators (DO, DOC, Cl, HCO, pH, NO, and SO), petroleum hydrocarbons elements and environmental isotopes (δN, δO, δC, and δC). With the aid of GIS, statistical analyses, as well as first-order decay model and electron-acceptor-limited kinetic model, the spatio-temporal evolution characteristics of the petroleum hydrocarbons were modeled. Results showed a positive natural attenuation trend over the last 3 decades where intrinsic biodegradation mechanism was found to be the most important factor driving the degradation of hydrocarbons in the aquifer system. The hydrogeochemical association between the indicators and petroleum hydrocarbons provided the evidences of biodegradation and also served as markers, highlighting the occurrence of anaerobic respiration without methanogenic activities within the heterogenous karst media. Furthermore, the mean natural attenuation rate of petroleum hydrocarbons was calculated to be 3.76 × 10/day whereby the current highest petroleum hydrocarbons concentration (361.13 μg/L) is estimated to be degraded completely in 6 years under the present hydrogeological and environmental conditions.
中国北方山东省淄博市一个罕见的特大破碎岩溶含水层被一家石化公司的石油烃污染。在过去的 30 年里，它一直是几项修复工作的重点。在这项研究中，使用水文地球化学指标（DO、DOC、Cl、HCO、pH、NO 和 SO）、石油烃元素和环境同位素（δN、δO、δC 和 δC）来阐明石油烃的污染和自然衰减特征。借助 GIS、统计分析以及一阶衰减模型和电子受体限制动力学模型，对石油烃的时空演化特征进行了建模。结果表明，在过去的 30 年里，存在着积极的自然衰减趋势，内在的生物降解机制被发现是驱动含水层系统中烃类降解的最重要因素。指标与石油烃之间的水文地球化学关联提供了生物降解的证据，也作为标记物，突出了在非均质地岩溶介质中发生的无氧呼吸而没有甲烷生成活动。此外，计算得出石油烃的平均自然衰减率为 3.76×10-3/day，在目前的水文地质和环境条件下，当前最高的石油烃浓度（361.13μg/L）估计在 6 年内将完全降解。
