【作者】 周安文；

【导师】 郭正元；

【作者基本信息】 湖南农业大学 ， 环境工程， 2004， 硕士

【摘要】 本文采用批量平衡法研究三唑酮在土壤中的吸附性能，以柱淋溶法研究三唑酮在土壤中的垂直移动能力，并测定了三唑酮在不同浓度处理下不同培养时间内对土壤过氧化氢酶和脲酶活性的影响，主要研究结果如下： 三唑酮在土壤中的吸附符合Freundlich方程，lgC_s与lgC_eq的相关系数R²达0.9677-0.9926，呈极显著相关性。随着土壤溶液中三唑酮浓度的升高，土壤吸附三唑酮的量呈非线性等温吸附，吸附等温式C_s=K_dC_eq^l（?）n中，l/n的值为0.7753-0.9874，可认为是一种非线性关系。其吸附性能K_d值与土壤有机质含量、粘粒含量有很大的关系，两者的相关系数R²分别为0.9364和0.95，而与土壤阳离子不呈线性相关性。平均K_oc为256，表明三唑酮在土壤中移动性属于中等类化合物。三唑酮在土壤中的吸附量随温度的升高而减少，吸附性减弱；在土壤中的吸附为物理吸附。 在200mm模拟降雨下经24h的不饱和淋溶，三唑酮在四种土壤中的移动能力从大到小的顺序为：河潮土＞红壤＞红黄泥＞麻沙泥，分别有15.87％、9.56％、0.72％、0.68％的三唑酮被淋出。相对于不饱和淋溶，在饱和淋溶下，淋出液中三唑酮的量增加了20.21％，表明三唑酮在土壤中的移动性增强。在模拟酸雨的淋溶作用下，三唑酮在土壤中的移动性呈减弱趋势，并且随着酸雨pH的降低，淋出液中的三唑酮含量相对于对照分别减少了22.89％（pH4.5.）和34.36％（pH3.5），淋溶迁移能力减弱，说明三唑酮在土壤中的吸附量随pH值的降低而增加，在土壤中的移动能力减弱。 在低浓度（1～10mg/kg）下三唑酮对土壤过氧化氢酶活性的抑制作用时间较短，仪为一天，随着培养时间的延长，抑制作用减弱，主要表现为激活作用，激活率呈现“增强一减弱”的变化趋势。而高浓度下（50mg/kg）则抑制作用较强，抑制期长达20天。对土壤脲酶活性的抑制作用较强，恢复的速度也较慢。各浓度下的脲酶活性受到不同程度的抑制作用，抑制期长达20天以上。在整个试验条件下，脲酶活性呈现出“抑制-恢复”变化规律。更多还原

【Abstract】 The adsorption of triadimefon in four tested soils with a batch equilibrium method and leaching in soil columns were studied .The influence of triadimefon on the activity of catalase and urease in soil under different concentration and different cultivated time was also studied.The main results were summarized as following:The adsorption of triadimefon in tested soils gave an approximate fit to the Freudlich empirical equation ,the range of R2 values between 1gCs and 1gCeq, was from 0.9677-0.9926,which indicated the most distinct correlation.Adsorption was not proportional to solution concentration with a constant partitioning of triadimefon between the solution phase and the sorbent. In the isotherm equation Cs=KdCeq1/n , the range of 1/n values was 0.7753-0.9874,which also showed the degree of isotherm nonlinearity.The adsorption mainly influenced by organic and clay content,which were positively correlated with Kd values ,the R2 values respectively were 0.9364 and 0.95.But the cation was not correlated with Kd values. The average Koc values for four tested soils was 256.According to the classification of mobility of pesticide in soil ,the mobility of triadimefon in soil belonged to the medium .The quantities of triadimefon adsorbed by soil got down with the increasing tempreature.The adsorption in soil belonged to physical adsorption.under the control of 200 mm water falling through the four unsaturated soil columns during 24h,the order of the mobility of triadimefon in soil was Hechao soil >red soil >reddish yellow soil >Masha soil ,the quantities of triadimefon leached out respectively were 15. 87%, 9. 56%, 0.72%, 0.68% .Compared with unsaturated soil column, in saturated soil column,the quantities of triadimefon leached out increased 20.21%,which indicated that the mobility of triadimefon in saturated soil increased. While 200 mm stimulated acide rain falling through unsaturated soil columns, the mobility of triadimefon in soil got down As the acidity of simulated acid rain were raised, the quantities of triadimefon in leaching water decreasing 22.89% (pH was 4.5)and 34.36%(pH was 3.5) .Which indicated that the adsorption of triadimefon in soil increased with the decreasing of pH values.While under the concentration of 1 mg/kg and 5 mg/kg, The activity of catalase was inhibited by triadimefon, the term was short, only one day. As the cultivated time got long, the inhibiition got weak, showed as stimulation.The tendency of activation was "get strong -get weak". Under 50 mg/kg, the time of inhibition was as long as 20 days . The inhibition of triadimefon to urease was stronger than that of catalase. And its revive time was also very late. The time of inhibition was over 20 days. During the whole experiment, the activity of urease expressed as "inhibition -revive".Author: Zhou Anwen(Encironmental Science and Engineering) Directed by: Associated professor Guo Zhengyuan更多还原