石油污染土壤生物修复过程中影响修复效果和土壤毒性的因素分析

Factors Analysis of Affecting Soil Toxicity and Bioremediation Efficiency in Bioremediation of Petroleum Contaminated Soil

研究了不同生物修复方式对油田区长期污染土壤的修复效果,分析了石油污染物同微生物变量及土壤理化性质变量的典型相关性。在90d的修复过程中,对土壤中石油烃、微生物性质变量、土壤理化性质变量以及土壤毒性进行测定。结果表明,添加氮磷钾复合肥、褐煤粉和诺沃肥的生物刺激方法对土壤中总石油烃及饱和烃的去除率最高。添加菌剂的生物强化方法对土壤中芳香烃和16种多环芳烃的去除率最高,且土壤毒性降低最明显。典型相关分析结果表明,土壤中总石油烃和饱和烃的降解与总异养菌数、脱氢酶活性、脂肪酶活性及氮的含量相关;土壤中芳香烃的降解与石油烃降解菌数有关,并对修复后的土壤毒性产生影响。

This study investigated the effectiveness of different techniques to enhance petroleum hydrocarbon bioremediation in a chronically contaminated oilfield soil,and explored the canonical correlations among hydrocarbon concentration,microbial properties and soil physicalchemical variables.During the90d incubation,soil samples were collected and analyzed periodically to determine the amounts of residual hydrocarbons,soil toxicity,microbial properties and soil physicalchemical parameters.The results showed that the greatest degradation of total petroleum hydrocarbons(TPH)and saturate fraction of hydrocarbons was observed with the biostimulation using a combined amendment(mixture of NPK fertilizer,brown coal dust and a fermentation waste,NovoGro).Bioaugmentation using exogenous hydrocarbondegrading microbial consortium significantly enhanced the removal of the aromatic fraction and16PAHs of the petroleum hydrocarbons,thus greatly decreased the soil toxicity.Canonical correlation analysis showed that the degradation of TPH and saturated hydrocarbons was mainly related to the total heterotrophic bacteria number,dehydrogenase activity,lipase activity and soil nitrogen content.In addition,the degradation of soil aromatic hydrocarbons was mainly related to the number of hydrocarbondegrading microorganism and the soil biological toxicity.