污泥农用后有机复合污染土壤强化修复初步研究

Remediation of Soil Contaminated by Mixed Organic Pollutants in Sewage Sludges from Yangtze River Delta Region

通过室内模拟试验,以持久性有机污染物(POPs)中毒性较强的多氯代有机污染物多氯联苯(PCBs)和有机氯农药(OCPs)为目标污染物,以不同碳源和水分条件为调控因子,研究了淀粉和葡萄糖等不同来源的碳、水分条件及其联合措施对污泥农用后多氯联苯(PCBs)和有机氯农药(OCPs)复合污染的长江三角洲地区土壤中两种有机污染物的削减影响及其贡献大小。结果表明,土壤水分含量为正常田间持水量时,加入淀粉和葡萄糖等碳源均一定程度地促进了真菌和细菌数量的增加,从而促进了土壤中PCBs和OCPs的降解;淹水可促进土壤中PCBs的降解,在一定程度上也促进了土壤中OCPs的降解。

An incubation experiment was carried out with agricultural soils in theYangtze River Delta Region under different carbon sources and soil moisture contents. The soil used in the cultivation experiment had been contaminated by polychlorinated biphenyls （PCBs） and organochlorine pesticides （OCPs） after sewage sludge were applied in the farmland soils. The effect of the enhanced remediation and the dynamic of soil microbial ecology during the remediation were investigated. The incubation experiment showed that different carbon sources such as glucose and starch were all beneficial to the growth of soil microorganisms, thus accelerated the degradation of PCBs and OCPs in polluted soils. The degradation effects of soil microorganisms on PCBs and OCPs in soil were not only related with carbon sources, but also closely related with the soil moisture. Higher soil moisture was helpful for the growth of soil microorganisms such as bacteria and fungi, thus enhanced the metabolic activities of soil microorganisms and accelerated the natural degradation of PCBs and OCPs in soil. These results pro- vided scientific evidence for further studies on the conditions for natural degradation of soil PCBs and OCPs and could help to develop biore- mediation techniques for persistent organic pollutants （POPs） in polluted soils.