乙氧氟草醚在模拟稻田-鱼塘生态系统中残留动态的研究

在野外稻田-鱼塘模拟系统研究了乙氧氟草醚以规定剂量72g/hm2施用于田间后的残留分布及消解动态?结果表明,施药后4h该药在稻田表水和鱼沟中的浓度分别为29.4和19.6μg/L,在稻田土?鱼塘水和塘泥中的最大浓度分别为0.752,0.006和0.156mg/L?且在各介质中消解迅速,在田表水?塘水?田土中的半衰期分别为4.5,48.8h和7.2d?说明该药对水生生物虽有较高毒性,但在规定使用剂量下,其在稻田及邻近鱼塘中的残留浓度与毒性已降到对其中的水生生物不再有危害的水平?因此可认为该农药在稻田使用对水生生物无实际危害作用? 

Study on the Residues and Degradation of Oxyfluoren in a Simulation Rice Field and Pond Eco-system

The distribution and the degradation of Oxyfluoren residues in a simulation rice field and pondeco-system were studied after application in field with the recommended dosage of 72 g/hm 2.The results show that theresidues concentrations in rice field water and fish ditch water after 4 h are29.6 and 19.6μg/L,respectively.The biggest concentrations in rice field soil,fish pond water and pond sludge are 0.752,0.006,and 0.156mg/L,respectively.Andthe residues degradation in all media are rapid with half-life of 4.5 h in rice field water,48.8h in pond water and 7.2d in rice field soil,respectively.The residues concentration in field and adjacent waters are observed to decrease to the level of non-damage to the aquatic organisms.So it can be considered that Oxyfluoren is safe to fish in the rice field and pond eco-system if it is applied with recommended dosage.