新型杀虫剂锐劲特农药对甲壳类水生生物影响研究

 通过建立稻田 -鱼塘模拟生态系统 ,研究锐劲特农药 (Fipronil)在稻田 -鱼塘模拟生态系统中的迁移、转化规律 ,及其对蟹、虾等水生生物的影响。结果表明 ,农药锐劲特悬浮剂施入稻田初期 ,5 0 .7%被水稻植株沾附 ,38.5 %进入稻田水 ,稻田水中的锐劲特最高浓度达 0 .0 32mg/L。施药 2 4h后 ,将部分稻田水排入邻近鱼塘 ,水塘水体中锐劲特最高浓度达 0 .0 0 35mg/L。锐劲特在水体中极难降解 ,它在鱼塘水体中的降解半衰期达 77.2d。试验同时表明 ,蟹、虾对锐劲特极为敏感 ,对罗氏沼虾、青虾、螃蟹的 96hLC50 仅为 0 .0 0 10、0 .0 0 43和 0 .0 0 86mg/L。在模拟生态系统中 ,施用锐劲特对邻近鱼塘内的蟹、虾有一定的危害。因此锐劲特在我国稻田地区施用时 ,应注意其对周围蟹、虾养殖的安全。

Impacts of Fipronil on Aquatic Organisms in Paddy-fish Pond Ecosystem

A paddy field and fishpond simulation ecosystem was established to study the Fipronil pesticide environment behavior and its effects on crab and shrimp in the ecosystem. The results showed that 50.7% of Fipronil was adhered by rice plant and 38.5% was dropped into paddy water after the pesticide used, the highest concentration of Fipronil in paddy water was 0.032 mg/L. 24 h later a part of paddy water was overflowed into the treated fishpond, the highest concentration of Fipronil in adjacent fish-pond water reached 0.0035 mg/L. Fipronil was difficult degraded in the pond water, the half-life was 77.2d in the water. Fipronil is very sensitive to crab and shrimp, 96h LC 50 of Fipronil to Macrobrachium rosenbergii?Macrobrachium nipponensis?Eriocheir sinensis was 0.0010?0.0043 and 0.0086mg/L respectively. The crab and shrimp were damaged by Fipronil in the simulation ecosystem. It is suggested that we must pay attention to the safety of Fipronil if it is used in some areas of paddy rearing crab and shrimp.