参后地土壤中五氯硝基苯微生物修复效应及影响因素研究

Study on the Technology of Slurry Phase Bioremediation for PCNB in Soil

从长期使用五氯硝基苯(PCNB)的栽参土壤中筛选对PCNB具有降解效能的菌株(S1、S2、S3),研究其对PCNB的降解效能及影响因素。结果表明:适合各菌株生长的适宜温度为20～30℃;适合S1和适合S2、S3菌株生长的pH范围分别为5.5～7.5和6.5～8.5。在此pH和温度范围内,各菌株对PCNB具有良好的降解性能。在最佳生长条件下,菌株达到最大生长量和最高降解率,在PCNB初始浓度为25.0mg/L时,经过数天的培养,对PCNB降解率最高可达89.7%。与对照相比,土著微生物和接种微生物均能加速PCNB的降解。对泥浆相修复和纯培养基条件下的PCNB降解反应的回归方程进行差异显著性检验表明:在两种条件下,PCNB生物降解速率差异显著性达到α=0.01水平。

Three strains（S1, S2, S3）that can degrade organic PCNB pesticide were selected from soil where ginseng had been grown and PCNB had been applied for many years. The studies on efficacy of degradation and the factors of biodegradation showed that the optimum temperature range for strain growth and PCNB-degradation was 20--28℃. The strain SI had a good PCNB-degradation capability when the pH value was 5.5--7.5, and S2 and S3 grew better when the pH value was 6.5--8.5. The strains could degrade 89.7 % of the initial concentration of 25.0 mg/L PCNB in several days. Compared with the com- parison, indigenous microorganism and vaccination microorganism both can accelerate the degradation of PCNB. The difference-significance of biodegradation-rates under the conditions that slurry phase bioreme- diation and pure cultivation had achieved level α=0.01. The resuhs can provide theoretical basis and basic information for bioremediation of PCNB-polluted soil, and have reference value of adopting degenera- tion microorganism to depredate PCNB in the PCNB contaminated soil.