化学氧化剂-微生物协同作用对除草剂氟乐灵降解过程的影响

摘要

氟乐灵在水产养殖中常被用来清除池塘底部青苔,但是使用过后也会对鱼类产生毒性.因此,清除水体过量的氟乐灵对养殖后期鱼类生长极其重要.选取过碳酸钠和过硫酸氢钾为研究对象,在比较2种氧化剂降解效果的基础上,研究了化学氧化剂-微生物协同作用对除草剂氟乐灵降解过程的影响.结果显示,过碳酸钠比过硫酸氢钾更适宜作为化学氧化剂对养殖水体中氟乐灵进行降解.单独使用0.15 mg·L-1过碳酸钠和φ=0.01%比例、添加浓度为109 CFU·mL-1的FJ-01菌液中微生物对氟乐灵5 d的降解率分别为44.79%和66.78%,而两者结合处理时5 d的降解率高达75.87%,显著优于单一的微生物降解或化学氧化.该研究表明化学氧化剂和微生物协同降解是水产养殖中氟乐灵污染水体修复的良好途径和方法.%Trifluralin is often used in aquiculture to clear off green moss in the bottom of a fish pond, but it is found to have some toxic effect on fish. It is, therefore, essential to remove excessive trifluralin from the pond for the growth of the fish at their late stages. In this paper two chemicals, sodium percarbonate and potassium persulfate, were tested as oxidant. Based on comparison between the two in trifluralin degradation effect, further studies were done on synergistic effects of the chemicals and bacteria on degradation process of trifluralin. Results show that sodium percarbonate is more suitable than potassium persulfate for use as oxidant to oxidize trifluralin in fish ponds. The separate use of 0. 15 mg·L-1 sodium per?carbonate and 0. 01% 109 CFU·mL-1 FJ-01 bacteria degraded trifluralin by 44. 79% and 66. 78% within 5 days, respec?tively, while the two used together increased the degradation rate significantly up to 75. 87%. The findings indicate that the use of chemical oxidant and bacteria together is an effective method of remedy trifluralin polluted pond water. The study may shed light on the issue of quality safety of aquatic product.