石油污染盐碱土壤生物修复模式研究

目的]寻找适宜的石油污染盐碱土壤的野外生物修复模式。方法]以实验室前期保存和新筛选的石油降解细菌菌群为基础,制备固体菌肥,首先在室内条件下研究C∶N∶P、菌肥施入量对降解率的影响,并将菌肥施入量、植物种类、土壤翻耕对野外土壤污染修复效果的影响进行试验研究。结果]菌肥的降解特性决定了石油污染物的降解效率,无效的菌肥在室内外试验中都会削减石油污染物的修复效果;在适宜的土壤C∶N∶P条件下,新鲜菌肥的施入量增加,可有效提高石油污染物的降解率。足够的菌肥施入量能够在短期内(10~20 d)发挥高效降解作用。在野外修复模式研究中,翻耕对扰动盐碱土壤的石油污染修复作用有限,土著优势植物碱蓬比苜蓿更适于植物-微生物的联合修复。结论]在野外条件下,适宜的盐碱土壤石油污染修复模式为碱蓬+10%新鲜菌肥+不翻耕+营养(C∶N∶P=100∶5∶3)。

Study on Bioremediation Mode of Saline Soil Contaminated by Petroleum

Objective]To find a suitable bioremediation model for petroleum contaminated saline soil.Method]Based on the oil-degrading bacteria flora saved by experiment previously and screened freshly,the solid fertilizer was prepared.The effect of C∶N∶P and the quantity of solid fertilizer on oil-degradation rate and amount of microbe were studied,and the impact of quantity of solid fertilizer applied,kinds of plant,tillage on remediation of contaminated soil in the field were studied by experiment.Result]Degradation characteristics of fertilizer determined the degradation efficiency of petroleum pollutants,remediation invalid fertilizer will reduce oil pollutants in both indoor and outdoor test.In the soil C∶N∶P under appropriate conditions,the fresh fertilizer application amount increased,which can effectively improve the degradation of oil pollutants.Enough fertilizer can play a role the degradation in the short term (10-20 d).In the field remediation model,the effect of tillage on the remediation of contaminated saline soil was limited.The indigenous dominant plant Suaeda glauca was more suitable for phytoremediation than Medicago sativa.Conclusion]Under field conditions,the appropriate bioremediation mode for saline soil contaminated by oil was Suaeda glauca + 10% fresh bacterial fertilizer +no tillage + nutrition (C∶N∶P=100∶5∶3).