高效除草尿素(药肥)对稻区非目标生物影响研究

Side effects of weeding carbamide on non target organisms in paddy fields

研究了高效除草尿素 (药肥 )对稻区水生生物的影响。结果表明 ,药肥对蟾蜍 Bufo bufo gargarizans蝌蚪、棘胸蛙 Ranaspinosa蝌蚪、食蚊鱼 Gambusia affinis、虹鳟 Salmo gairdneri、湖螺 Ballamya sp和蚤状蟤 Daphnia pulex的 96h LC5 0 分别为 5436、1 579、 40 73、 568、 41 39和 9781 mg/ L。按照用量和目前国内外普遍采用的评价标准 ,药肥对蟾蜍、食蚊鱼、湖螺和蚤状蟤低毒 ,对棘胸蛙和虹鳟具有中等毒性。生长潜力试验表明 ,小球藻 Chlorella sp.和删藻 Scenedesmussp.对药肥敏感性不同 ,但是在 mg/

Side effects of weeding carbamide on several non target aquatic organism were studied.The results showed that the 96 hours LC 50 of the tadpole of Bufo bufo gargarizans and Rana spinosa,mosquitofish (Gambusia affinis),rainbow trout (Salmo gairdneri),water snail (Ballamya sp.),and water flea (Daphnia pulex) were 5436,1579,4073,568,4139 and 9781 mg/L,respectively.According to the criteria widely accepted,the carbamide was regarded as low hazardous to Bufo bufo gargarizans,Gambusia affinis,Ballamya sp.and Daphnia pulex,and moderately hazardous to Rana spinosa and Salmo gairdneri.A growth inhibition test indicated that the green algea,Chlorella sp.and Scenedesmus sp.were different susceptibility to the carbamate.Biomass for both species was increased after a 3 4 weeks incubation in 200 mg/L solution,but the rate of increase was not so remarkable as those in the common carbamate.