有机氯农药在长春南湖表层沉积物中的生物降解动力学分析

分析了γ-HCH和p,p’-DDT为代表的有机氯农药进入湖泊表层沉积物环境后的生物降解动力学特征,通过在实验室模拟水体-沉积物体系,比较灭菌样品与原样品的降解动力学过程,并综合分析体系中主要指标与降解速率之间的动态联系。结果表明农药残留动态的非线性动力学方程与实验数据拟合较好,相关系数范围为0.901～0.989,原样品的拟合效果优于灭菌样品。实验中γ-HCH和p,p’-DDT的生物降解率分别为44.4%和17.2%。降解体系溶解氧、氧化还原电位、总有机碳指标与生物降解速率之间的动态联系主要通过微生物的降解活性相联系。

Biodegradation Kinetic Analysis of Organochlorine Pesticides in Surface Sediments from Nanhu Lake in Changchun City

The purpose of this study is to investigate the dynamic characteristics of γ-HCH and p,p’-DDT as the models for organochlorine pesticides in surface sediments of lakes.Water-sediment systems are built to simulate the degradation kinetics of sterilized samples and the original samples and to analyze the relationship between main index and degradation rate are analyzed.The result indicated that the nonlinear dynamics model was adopted to fit the experimental data,the range of correlation coefficient of nonlinear model was 0.901～0.989.The model simulated results of original samples showed higher fitness and accuracy than those of sterilized samples.Biological degradation rate were 44.42% for γ-HCH and 17.23% for p,p’-DDT in the experiment.Indicators including dissolved oxygen,redox potential and total organic carbon influence degradation rate through affecting the activity of microorganism.