底泥中多环芳烃的微生物降解与原位修复技术

水体底泥是多环芳烃(PAHs)重要的环境载体之一,PAHs通过多种途径进入各种水体,经过复杂的过程沉积富集于水体底泥中。PAHs在环境中的迁移转化有多种途径,其中微生物降解是去除环境中PAHs的最主要途径。PAHs可以作为微生物的唯一碳源或通过共代谢而被降解。影响微生物降解PAHs的因素有:PAHs的生物可利用性、温度、pH值、供氧条件、营养条件以及其它的环境因素。受PAHs污染底泥的微生物原位修复技术通过导入高效微生物,提供电子受体、营养盐和表面活性剂等来降解底泥中的PAHs。该技术被认为是去除底泥中PAHs污染物的重要手段,但还存在着多方面的缺点而使其应用存在着很大的局限性,需要从高分子量的PAHs的降解机理、生物降解过程中基因调控机制、环境因子与微生物降解PAHs的相互作用关系以及受PAHs污染底泥的微生物原位修复过程的监测、风险评估和效果评估等多个方面进行深入的研究。

Overviews of Biodegradation of PAHs and In situ Remediation of PAHs-contaminated Sediment

Sources of polycyclic aromatic hydrocarbons ( PAHs) and their pathways into sediments of various water bodies are described and mechanism of PAHs degradation by microorganism in benthic environment, where PAHs serve as a solo carbon source of the microorganism is reviewed. Technologies of in situ remediation of PAHs-contaminated sediment, which often involves introducing efficient microorganism, providing electronic acceptor, nutrient and surfactant are briefly introduced. Based on the analysis of drawbacks of the remediation technologies available, some suggestions for further study such as degradation mechanism of high-molecular-weight PAHs, use of genic control technique and the relationship between PAHs degradation and environmental factors, as well as the monitoring, risk assessment and effectiveness evaluation in association with the sediment remediation were put forward.