【作者】 何文；

【导师】 郭正元；

【作者基本信息】 湖南农业大学 ， 环境工程， 2006， 硕士

【摘要】 本文选用三叶浮萍和蝌蚪为对象，评价了异恶草酮在水环境中的毒性作用，并研究了其水解规律及其影响因素。主要研究结果如下： 以三叶浮萍为对象，研究了异恶草酮对其生长及体内色素的影响作用。结果表明：异恶草酮对浮萍生长抑制的24h LC₅₀为8.86mg／L、48h LC₅₀为5.21mg／L、72h LC₅₀为1.92mg／L、96h LC₅₀为1.66 mg／L。异恶草酮对浮萍体内色素的影响作用呈良好的“浓度、时间—效应”关系。随着处理浓度的增大，浮萍体内的叶绿素和胡萝卜素含量明显减少，且叶绿素a／b值也随处理浓度的增大而减小。 研究了水环境中异恶草酮与镉共存时对蝌蚪的联合毒性。在常温20℃下，异恶草酮对蝌蚪的24h、48h、72h、96h LC₅₀分别为15.62mg／L、14.27mg／L、13.35mg／L、13.30mg／L；镉对蝌蚪的24h、48h、72h、96h LC₅₀分别为5.63mg／L、3.54mg／L、2.61mg／L、2.06mg／L；异恶草酮与镉共存对蝌蚪联合毒性的24h、48h、72h、96h的相加指数AI分别为0.25、0.21、0.19、0.14，均大于0，两者的联合毒性表现为协同作用。另随着水环境温度的升高，异恶草酮对蝌蚪的毒性减弱，而镉对蝌蚪的毒性增强，两者的联合毒性仍表现为协同作用。 采用HP-1100液相色谱分析和室内模拟的方法研究了异恶草酮在不同温度和PH值条件下的水解动力学情况，以及在三种实际环境水样中的水解情况。结果表明，pH的变化值对异恶草酮的水解速率影响较小，异恶草酮水解速率随温度升高而加快，而且异恶草酮在环境水样中的水解速率较慢。更多还原

【Abstract】 Regard the Lemna minor L and Rana limnocharis as the target,researched the toxicity of the Clomazone,and studied the hydrolysis dynamics of Clomazone and its factor.The main results summarized as following:Regard the Lemna minor L as the target,studied the influence of the Clomazo--ne to its growth and its pigment.The result indicat that the toxicity of the Clomaz--one to Lemna minor L’s 24h IC₅₀ is 8.86 mg/L, 48h IC₅₀50 is 5.21 mg/L、 72h IC₅₀ is 1.92mg/L、 96h IC₅₀ is 1.66 mg/L.The influence of Clomazone to the pigment in Lemna minor L accords with the dosage-effect connection.With the dosage ’s incr--ease,the chlorophyll and the carotene in Lemna minor L reduce obviously,and the value of chlorophyll a/b reduces too.Joint-toxicity of Clomazone and Cadmium on Rana limnocharis was studied in the present investigation. It was demonstrated that LC₅₀ of Clomazoneon Rana limnocharis were 15.62mg/L、 14.27 mg/L、 13.35 mg/L, 13.30 mg/L,While that of Cadmium were 5.63mg/L、 3.54 mg/L、 2.61 mg/L、 2.06 mg/L,respectively. Accord--ing to the addictive index method of Marking,It has been found that the addictive index（AI）were 0.25、 0.21、 0.19 and 0.14 in 24 h, 48 h 72h and 96 h respectively. revealing that there is a clear synergism action. And with the temperature’s incre--ase, the toxicity of Clomazone on Rana limnocharis was weakened,While that of Cadmium on Rana limnocharis was strengthened,and the Joint-toxicity of the two is still a synergism action.The hydrolysis dynamics of Clomazone was studied at different temperatures、 pH values and in three kinds of natural water. The results indicated that different pH Values affect the hydrolysis of Clomazone,While the hydrolysis rate accelerated with the rise of the temperature.Moreover,the hydrolysis of Clomzone in naturalwater was a little slower.更多还原