Khanafer Majida, Almutairi Awatef, Al-Awadhi Husain
Department of Biological Sciences, Faculty of Science, Kuwait University, P.O.Box 5969, Safat, 13060, Kuwait.
Department of Biological Sciences, Faculty of Science, Kuwait University, P.O.Box 5969, Safat, 13060, Kuwait.
J Environ Manage. 2025 Aug;389:126196. doi: 10.1016/j.jenvman.2025.126196. Epub 2025 Jun 19.
This study investigates the efficiency of different bioremediation techniques in cleaning a desert soil sample saturated with crude oil. The soil was divided into three cores; two cores were regularly irrigated with either tap water or raw sewage effluent and mixed thoroughly, while the third core remained untreated as a control. Three parallel cores of pristine soil samples were also set for comparative analysis of microbial communities. The cores were exposed to natural environmental conditions for 10 months. The results of the study showed that bioremediation in the oil-saturated soil samples occurred via the activities of the indigenous bacteria, demonstrating self-cleaning. Oil-removal efficiency in the untreated soil samples reached 79.6 % after 10 months incubation. Water- and sewage effluent-irrigation along with soil mixing improved the environmental conditions in the polluted soil samples, thus enhancing the growth and propagation of hydrocabonoclastic bacteria, accelerating oil-biodegradation to 94 % and 97.4 %, respectively. Both culture-dependent and culture-independent analyses revealed significant shifts in bacterial community composition due to oil introduction and treatment type. The culture-independent method revealed TM7a, A4b, and Skermanella as the most abundant taxa. Conversely, the culture-dependent method identified Arthrobacter spp., Georgenia sediminis, Mycobacterium doricum, Pseudomonas spp., and Sinorhizobium meliloti as the predominant hydrocarbonoclastic indigenous bacteria in the untreated and water-irrigated soil. In the sewage effluent-irrigated soil, Aeromonas and Enterobacter dominated using the culture-dependent method, while JG30-KF-CM45 was the most abundant, with no coliform detection in the culture-independent method. The current study showed that self-cleaning of oil-saturated soils could be accelerated using cost-efficient methods.
本研究调查了不同生物修复技术对被原油饱和的沙漠土壤样本的清理效率。土壤被分成三个土芯；两个土芯分别用自来水或未经处理的污水定期灌溉并充分混合，而第三个土芯作为对照未作处理。还设置了三个平行的原始土壤样本土芯用于微生物群落的比较分析。这些土芯在自然环境条件下放置10个月。研究结果表明，饱和油土壤样本中的生物修复是通过本地细菌的活动发生的，显示出自我净化能力。未经处理的土壤样本在培养10个月后，除油效率达到79.6%。用水和污水灌溉并进行土壤混合改善了污染土壤样本的环境条件，从而促进了烃分解菌的生长和繁殖，分别将油生物降解加速至94%和97.4%。基于培养和不依赖培养的分析均显示，由于原油引入和处理类型的不同，细菌群落组成发生了显著变化。不依赖培养的方法显示TM7a、A4b和斯氏菌属为最丰富的分类群。相反，基于培养的方法确定节杆菌属、沉积嗜盐菌、多里考分枝杆菌、假单胞菌属和苜蓿中华根瘤菌是未处理和用水灌溉土壤中主要的烃分解本地细菌。在污水灌溉的土壤中，基于培养的方法显示气单胞菌属和肠杆菌属占主导，而不依赖培养的方法中JG30-KF-CM45最为丰富，未检测到大肠菌群。当前研究表明，使用具有成本效益的方法可以加速饱和油土壤的自我净化。
