State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, Nanjing, 210008, People's Republic of China,
Environ Sci Pollut Res Int. 2014;21(13):7785-96. doi: 10.1007/s11356-014-2703-4. Epub 2014 Mar 19.
The present study was conducted to investigate the anaerobic biodegradation potential of biostimulation by nitrate (KNO3) and methyl-β-cyclodextrin (MCD) addition on an aged organochlorine pesticide (OCP)-contaminated paddy soil. After 180 days of incubation, total OCP biodegradation was highest in soil receiving the addition of nitrate and MCD simultaneously and then followed by nitrate addition, MCD addition, and control. The highest biodegradation of chlordanes, hexachlorocyclohexanes, endosulfans, and total OCPs was 74.3, 63.5, 51.2, and 65.1%, respectively. Meanwhile, MCD addition significantly increased OCP bioaccessibility (p < 0.05) evaluated by Tenax TA extraction and a three-compartment model method. Moreover, the addition of nitrate and MCD also obtained the highest values of soil microbial activities, including soil microbial biomass carbon and nitrogen, ATP production, denitrifying bacteria count, and nitrate reductase activity. Such similar trend between OCP biodegradation and soil-denitrifying activities suggests a close relationship between OCP biodegradation and N cycling and the indirect/direct involvement of soil microorganisms, especially denitrifying microorganisms in the anaerobic biodegradation of OCPs.
本研究旨在探讨在老化的有机氯农药（OCP）污染稻田土壤中，通过硝酸盐（KNO3）和甲基-β-环糊精（MCD）添加进行生物刺激对厌氧生物降解的潜力。经过 180 天的培养，同时添加硝酸盐和 MCD 的土壤中总 OCP 的生物降解率最高，其次是添加硝酸盐、MCD 和对照。氯丹、六氯环己烷、硫丹和总 OCP 的最大生物降解率分别为 74.3%、63.5%、51.2%和 65.1%。同时，MCD 添加显著增加了通过 Tenax TA 提取和三室模型方法评估的 OCP 生物可利用性（p<0.05）。此外，添加硝酸盐和 MCD 还获得了土壤微生物活性的最高值，包括土壤微生物生物量碳和氮、ATP 产生、反硝化细菌计数和硝酸还原酶活性。OCP 生物降解与土壤反硝化活性之间的这种相似趋势表明，OCP 生物降解与 N 循环之间存在密切关系，土壤微生物，特别是反硝化微生物在 OCP 的厌氧生物降解中具有间接/直接作用。
