应用~(14)C核素研究草甘膦在水域生态系中的迁移、生物富集与消失动态

采用室内模拟与室外试验相结合的方法 ,研究了除草剂草甘膦在水域生态系统中的环境行为、生物富集作用和消失动态。表明该药进入水系后迅速向水生植物(金鱼藻CeratopyllumdemersumL .)和底泥中发生迁移 ;5～ 1 0d后以更快的速率向水生动物 (麦穗鱼Psudorasoboraparva)体内迁移并积累。 2 0d时的分配系数和生物富集系数分别达 8 59、2 7 96和 45 79,系统中草甘膦的浓度分布为麦穗鱼 >金鱼藻 >沉积物 >水体。鱼塘和河道用药后 ,草甘膦在水和沉积物之间的迁移及消失则更为迅速。

STUDIES ON TRANSFER, BIOACCUMULATION AND DISAPPEARANCE OF GLYPHOSATE IN THE AQUATIC ECOSYSTEM BY UTILIZING ~(14)C TRACER TECHNIQUE

Studies on transfer, bioaccumulation and disappearance of glyphosate in the aquatic environment were conducted with methods of model tests and outdoor trials in the aquatic ecosystem. The result showed that glyphosate transferred rapidly into sediment and hormwort ( Ceratopyllum demersum L.) after applied; and then, it was taken up faster and accumulated more by topmouth gudgeon ( Psudorasobora parva) 5～10 days after application. The partitioning coefficient (sediment water) and bioconcentration factors of glyphosate were 8 59, 27 96 and 45 79, respectively, in day 20. The concentration of glyphosate residue in the aquatic ecosystem followed the order of topmouth gudgeon>hormwort>sediment>water. And it was also indicated that glyphosate transferred and disappeared extremely fast in both pond and river after application.