Abstract

A petroleum hydrocarbon degrading bacterium Rhodococcus erythropolis KB1 was used to investigate the bioremediation efficiency of the petroleum contaminated desert steppe soils. The total petroleum hydrocarbons (TPHs) removal efficiency in the soils was analyzed with different treatments including natural degradation, bioaugmentation with R. erythropolis cells, biostimulation with nitrogen and phosphorus, and a combination of bioaugmentation and biostimulation. The petroleum contaminated soils were separately inoculated with R. erythropolis cells, nitrogen and phosphorus nutrients, a combination of the bacterial cells and the nutrients. The soil samples were kept at room temperature for 115 days of bioremediation. On the 66th day, the soil samples were strengthened with the same treatments. The results showed that the degradation rate of the natural degradation group was 20.20%. The biodegradation rates of the bioaugmentation group and biostimulation group were 36.02 and 40.10%, respectively. The combination group of bioaugmentation and biostimulation was the most effective way to remediate petroleum-contaminated soils with a degradation rate of 43.89%. In the bioremediation process the saturated hydrocarbons, especially the linear alkanes were the most easily degraded petroleum components. The cultivable bacterial counts of the soils were significantly increased in the bioaugmentation, biostimulation, and combined groups with bioaugmentation and biostimulation. The bacterial diversities of the petroleum contaminated desert steppe soil changed greatly when compared with that of the natural desert steppe soil. The bacterial structure and abundance of the soils in different treatments also changed significantly.

摘要

以石油烃类降解菌红球菌KB1 为研究对象，研究石油污染沙漠草原土壤的生物修复效率。在土壤中的总石油烃（TPHs）去除效率与不同的处理，包括自然降解，生物强化用分析R.红球菌细胞，用氮和磷生物刺激，和生物强化生物刺激和的组合。被石油污染的土壤分别接种了R. erythropolis细胞、氮和磷营养物质、细菌细胞和营养物质的组合。土壤样品在室温下保持 115 天的生物修复。在第 66 天，土壤样品用相同的处理加强。结果表明，自然降解组的降解率为20.20%。生物强化组和生物刺激组的生物降解率分别为36.02%和40.10%。生物强化与生物刺激相结合是修复石油污染土壤最有效的方法，降解率为43.89%。在生物修复过程中，饱和烃，尤其是直链烷烃是最容易降解的石油组分。生物强化组、生物刺激组和生物强化组和生物刺激组的土壤可培养细菌数显着增加。与天然荒漠草原土壤相比，石油污染荒漠草原土壤的细菌多样性变化很大。不同处理土壤的细菌结构和丰度也发生了显着变化。