2.4 固定化微生物修复水中阿特拉津的效果 - 农业环境科学学报.doc

玉米秸秆生物炭固定化Acinetobacter lwoffii DNS32性能研究 杨帆，江群，朱墨染，赵璐璐，闫立龙，张颖* （东北农业大学资源与环境学院，黑龙江省哈尔滨，150030） 摘 要：用玉米秸秆制备成生物炭，并以其作为固定化菌剂的廉价载体，与阿特拉津降解菌Acinetobacter lwoffii DNS32制备成具有吸附-降解性能的新型菌剂。结果表明：固定化菌剂可在40 h内对100 mg/L的阿特拉津降解率达94%，降解效率比游离菌高24%；固定化菌剂在pH=5和pH=10时，降解率分别为42%、35%，说明其能较好地抵抗pH的变化；温度为10℃时，固定化菌剂的降解率比游离菌高14%，说明其具有更好的耐寒性。为期30 d的模拟修复阿特拉津污染水的实验表明：生物炭固定化菌剂在30 d后仍然具有活性，说明该固定化菌剂具有高效且持久的阿特拉津污染修复效果。 关键词：生物炭；固定化菌剂；阿特拉津；生物降解 Degradation Properties of Immobilized Bacteria with Corn Stover Biochar as Carriers Abstract: Atrazine is widely used in the northeast of China and largely accumulated in environment. The technique of Immobilized-microorganism (TIM) is a potential effective approach for abating contamination with atrazine. Biochar application to soil can enhance soil quality and carbon sequestration because of its recalcitrance to decomposition. However few studies on the application of biochars as carriers to immobilize degrading-bacteria for remediation of contaminated water were reported. In this study, we prepared biochars using corn stover and then used those biochars as carriers to immobilize Acinetobacter lwoffii DNS32 for bioremediation of atrazine. Acinetobacter lwoffii DNS32, one of atrazine-degrading bacteria, which was screened by our cooperators in laboratory from atrazine contaminated soil. The results showed that the degradation rate of immobilized microorganisms can reach 98% by 40 h, which imply that degradation efficiency of TIM is higher than free bacteria (70%). When pH=5 and pH=10, the degradation rate of immobilized bacteria was 42% and 35% respectively, which shows they can resist pH change well. At 10 ℃, the degradation rate of immobilized bacteria is higher 14% than free bacteria, which certify that it has better cold tolerance. In the 30 d simulation repairing atrazine pollution water experiments, immobilized bacteria with corn stover biochar as carriers is still active after 30 d, indicated that the immobilized bacteria with efficient and lasting e