Biobed is a smart bioremediation system used to treat point-source pesticide contamination.Biomixture is the main component of biobeds,and pesticide dissipation is affected by its composition.This study aimed to compa...Biobed is a smart bioremediation system used to treat point-source pesticide contamination.Biomixture is the main component of biobeds,and pesticide dissipation is affected by its composition.This study aimed to compare the effectiveness of compost-based(C)versus peat-moss-based(P)biomixtures of biobeds on tested pesticide dissipation.Three concentrations(25,50,and 75 mg/kg)of chlorpyrifos,pendimethalin,and thiophanate methyl were added separately and as a mix to both biomixtures C and P.Our data showed the effect of biomixture type on the dissipation of the tested pesticides.For chlorpyrifos,its dissipation rate in biomixture P was more rapid than that in biomixture C.This result was confirmed by the mineralization kinetic experiment,since 25%of the initial ^(14)C-chlorpyrifos concentration accumulated in the form ^(14)CO_(2) in biomixture P compared to only 14%in biomixture C.In addition,the chlorpyrifos dissipation rate was influenced by the initial concentration when applied individually in biomixture P.In contrast,biomixture C was more effective at pendimethalin dissipation than biomixture P,since>76%of pendimethalin was dissipated in biomixture C versus 67%in biomixture P at the same incubation time.For thiophanate-methyl,the abilities of both biomixtures C and P were similar and less efficient than those of the other tested pesticides.The addition of the three tested pesticides to biomixture C only had a positive effect on both chlorpyrifos and thiophanate-methyl dissipation,while pendimethalin dissipation was similar when applied separately or as a mix.Microbial activity was stimulated by the addition of separately or mixed pesticides to biomixtures C and P as measured by dehydrogenase activity.展开更多
基金support provided by a joint research program financed by the Academy of Scientific Research and Technology(ASRT),Egypt and the Ministry of Foreign Affairs and International Development,the Ministry of Higher Education and Research,France.
文摘Biobed is a smart bioremediation system used to treat point-source pesticide contamination.Biomixture is the main component of biobeds,and pesticide dissipation is affected by its composition.This study aimed to compare the effectiveness of compost-based(C)versus peat-moss-based(P)biomixtures of biobeds on tested pesticide dissipation.Three concentrations(25,50,and 75 mg/kg)of chlorpyrifos,pendimethalin,and thiophanate methyl were added separately and as a mix to both biomixtures C and P.Our data showed the effect of biomixture type on the dissipation of the tested pesticides.For chlorpyrifos,its dissipation rate in biomixture P was more rapid than that in biomixture C.This result was confirmed by the mineralization kinetic experiment,since 25%of the initial ^(14)C-chlorpyrifos concentration accumulated in the form ^(14)CO_(2) in biomixture P compared to only 14%in biomixture C.In addition,the chlorpyrifos dissipation rate was influenced by the initial concentration when applied individually in biomixture P.In contrast,biomixture C was more effective at pendimethalin dissipation than biomixture P,since>76%of pendimethalin was dissipated in biomixture C versus 67%in biomixture P at the same incubation time.For thiophanate-methyl,the abilities of both biomixtures C and P were similar and less efficient than those of the other tested pesticides.The addition of the three tested pesticides to biomixture C only had a positive effect on both chlorpyrifos and thiophanate-methyl dissipation,while pendimethalin dissipation was similar when applied separately or as a mix.Microbial activity was stimulated by the addition of separately or mixed pesticides to biomixtures C and P as measured by dehydrogenase activity.
