多氯联苯对我国土壤微生物的生态毒理效应  

Ecotoxicity of Polychlorinated Biphenyls( PCBs) to Microorganisms in Chinese Udic-ferrosols and Aquic-cambosols

作　　者：程金金[1,2] 宋静[1,2] 吕明超 王兴祥[1,2] 

机构地区：[1]中国科学院南京土壤研究所土壤环境与污染修复重点实验室,南京210008 [2]中国科学院大学,北京100049

出　　处：《生态毒理学报》2014年第2期273-283,共11页Asian Journal of Ecotoxicology

基　　金：环保公益性行业科研专项经费项目(201009032);国家高新技术研究发展计划(863计划)项目(2009AA063104)

摘　　要：作为持久性有机污染物(POPs),多氯联苯(PCBs)一旦进入土壤将长期存留并对土栖生物产生潜在危害。土壤微生物是土壤生态系统重要组成部分,研究外源PCBs对土壤微生物的生态毒理效应,筛选出指示PCBs污染的敏感指标并获取可靠的生态毒理数据十分重要。研究以江西红壤和天津潮土为供试土壤,在室内25℃连续培养28 d的条件下进行了生态毒理实验,选择了微生物量碳、呼吸强度、代谢熵、硝化作用、脱氢酶活性、脲酶活性和微生物群落功能多样性为微生物指标。结果显示:1)在28 d培养时间内,多氯联苯(PCBs)的毒性作用随培养时间的延长而增强,且在红壤中的毒性作用强于在潮土中,表明PCBs对土壤微生物的毒性作用存在时间效应并受土壤性质的影响。2)各微生物指标的敏感性不同,微生物量碳、脲酶活性和微生物功能多样性对PCBs污染反应不够敏感,而土壤呼吸强度、代谢熵、硝化作用和脱氢酶活性对PCBs污染反应敏感。3)14 d时,红壤中PCBs对脱氢酶活性、呼吸强度和代谢熵的EC10值分别为1.20、3.18和1.09 mg·kg-1,而在潮土中分别为6.31、4.73和>50 mg·kg-1;28 d时,红壤中PCBs对硝化作用、脱氢酶活性、呼吸强度和代谢熵的EC10值分别为2.32、0.77、0.51和0.71mg·kg-1,而在潮土中分别为5.91、1.65、3.00和>50 mg·kg-1。综合考虑经济和实际需要等因素,建议将呼吸强度、硝化作用和脱氢酶活性作为PCBs污染土壤生态毒理评价中的首选敏感指标,并建议培养时间设置为28 d。Polychlorinated biphenyls （PCBs）, as persistent organic pollutants （POPs）, will persist in the soiland exert potential harm to the soil biota once they enter the soil environment. Soil microorganisms are impor-tant constituents of soil ecosystem. Therefore, it is necessary to investigate the ecotoxicological effects ofPCBs on different indicators of soil microorganisms, screen sensitive microbial indicators and accumulate relia- ble experimental data. In the present study, a microbial ecotoxicity test was conducted on an udic-ferrosols from Jiangxi and an aquic-cambosols from Tianjin at 25 ℃ for 28 days. And soil microbial biomass carbon, res- piration, metabolic quotient, nitrification, dehydrogenase activity, urease activity and microbial functional di- versity were chosen as microbial indicators. The results showed that the ecotoxic effect of PCBs on soil micro- bial indicators at day 28 was greater than that at day 14 in both soils. The microbial activity was less inhibited in the aquic-cambosols than that in the udic-ferrosols, which indicated that the ecotoxic effect of PCBs was influenced by incubation time and soil properties. The microbial indicators were different in their sensitivities to PCBs. It was found that soil microbial biomass carbon, urease activity and microbial functional diversity were not sensitive to PCBs pollution, while soil respiration, metabolic quotient, nitrification and dehydrogen- ase activity were sensitive to PCBs pollution. At day 14, the EC10 values of PCBs for dehydrogenase activity, respiration and metabolic quotient were 120, 3.18 and 1.09 mg·kg-1 in udic-ferrosols and were 6.31,4.73 and 〉 50 mg·kg-1 in aquic-cambosols. At day 28, the Eel0 values of PCBs for nitrification, dehydrogenase activity, respiration and metabolic quotient were 2.32, 0.77, 0.51 and 0.7l mg·kg-1 in udic-ferrosols and were 5.91, 1.65, 3.00 and 〉 50 mg·kg-1 in aquic-cambosols. For economic and practical reasons, soil respiration, nitrification and dehydrogenase activity and 28-day in

关 键 词：多氯联苯(PCBs) 红壤 潮土 土壤微生物 生态毒理 

分 类 号：X171.5[环境科学与工程—环境科学]