稻田使用溴氰菊酯农药对水生生物的安全评价

研究了在稻田－鱼塘生态系统中，模拟稻田使用溴氰菊酯后遇大雨，田水中残留农药流入鱼塘，对塘内水生生物的危害影响。结果表明:供试的鱼、贝类未发现死亡现象；残留、毒性测定结果与危害性实测结果相符。排水口附近供试虾类大量死亡。排水口较远处，虾类的危害影响较轻。虾类对溴氰菊酯有明显的回避性，自然水域中虾类的危害程度比关在网箱内的要小。鱼塘中浮游动物受害十分严重，但２周后即可恢复正常。使用溴氰菊酯农药对稻田养鱼无危害影响。 

Safety Evaluation of Deltamethrin on Aquatic Organisms in a Ricefield

It is studied of the effect of deltamethrin on aquatic organisms in a rice field-fish pond ecosystem, simulation that rainfall event began two hours after deltamethrin was applied to the rice field, and field water was all drained into the pond. Experimental results showed that: No death wad found of fish or oyster in the entire experimental period, and the measured results of residue and toxicity was correspond to that of harmness. A large of experimental shrimp around the drainage point died. The experimental shrimp of other area only had less effect and on death was found. Shrimp had a obvious avoidibility to deltamethrin, the harmness degree of deltamethrin on shrimp mat be lower in natural water than that of the netted in the experiment. The zooplanktons in the fish pond were seriously harmed after the field water was drained into the pond, but zooplanktons may returned to normal two weeks later. The experimental results showed that deltamethrin had no harmful effect to fish breeding in rice field.