石油污染盐碱土壤生物修复模式研究

Study on Bioremediation Mode of Saline Soil Contaminated by Petroleum

[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)。

[ 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 phytoremedi- ation than Medicago sativa. [ Conclusion] Under field conditions, the appropriate bioremediation mode for saline soil contaminated by oll was Suaeda glauca ＋ 10% fresh bacterial fertilizer ＋ no tillage ＋ nutrition （ C： N： P = 100： 5：3 ）.