氰戊菊酯在池塘生态系统中的消解

DISPERSION DYNAMICS OF FENVALERATE IN POND ECOSYSTEMS

对鱼塘直接喷施氰戊菊酯,用量为150g a.i./ha时引起鱼和其它水生动物的大量死亡,而60g a.i./ha时影响较小。氰戊菊酯在池水中消解较快,前期半衰期为11.1～31.2h,主要与农药向下层水或底泥的迁移有关,它的消解可用化学动力学的二室模型表示。氰戊菊酯在底泥中的消解可用一级吸收模型表示,它在后期的消解很慢,半衰期为43.3d。

This report describes dispersion dynamics of Fenvalerate in pond ecosystems. When Fenvalerate was applied at a dosage of 150g a. i. /ha to the surface of the ponds, there was a high mortality of fish and some species of aquatic invertebrates the day after treatment. On the contrary, at a dosage of 60g a. i. /ha, there was no significant hazard to aquatic animals. Dispersion of Fenvalerate in water was fast with half-life of 11. 1～31. 2 hours at the initial phase, and this was attributed to the migration of Fenvalerate toward subsurface water and sediment. The dispersion dynamics was described by two-compartmental model. Dispersion of Fenvalerate in sediment, with half-life of 43 days, was described by one-compartmental model.