作　　者： ; ; ; ; ;

机构地区： 四川省农药检定所

出　　处： 《西南大学学报（自然科学版）》 2009年第3期154-163,共10页

摘　　要： 对甲磺隆在土壤中的等温吸附-解吸特性进行研究，为其安全使用及对水资源的风险性评价提供理论依据．采用平衡振荡法和液相色谱法测定甲磺隆在8种土壤中的吸附-解吸行为，并运用数学模型对其在土壤的吸附-解吸特性及迁移性能进行分析．研究结果表明，甲磺隆在5^≠土壤中未产生吸附，在其余7种土壤中的等温吸附-解吸曲线符合Freundlich模型，其吸附以物理作用为主，吸附常数（Kf-ads）在0．466～3．219mg^1-n·L^n／kg之间，其中在2^#土壤中的等温吸附线属S型等温吸附线，而在其它土壤中属L型等温吸附线；其滞后系数（H）在0．167～0．670之间，解吸存在滞后现象．此外，Kf-ads和解析常数（Kf-ads）与土壤有机质含量和粘土含量呈正相关，而与土壤pH值呈负相关，平均滞后系数（Ha）与有机质含量和粘土含量呈负相关．进一步分析表明，甲磺隆在土壤中具有较低的吸附值，在土壤中具有一定的迁移能力，对水体存在风险．土壤有机质含量、粘土含量和pH在吸附-解吸过程中均属支配因素． The adsorption-desorption characteristics of metsulfuron-methyl in soils were investigated to provide basic data for evaluating its safe use in fields and the risk to water resources. The adsorption-desorption experiment was conducted by the batch equilibration and HPLC techniques, furthermore, data were analyzed with mathematic models to describe the characteristics and mechanism of adsorption-desorption and the shift of the herbicide in soils. The results showed that the adsorption-desorption isotherms of metsulfuron-methyl fitted for Freundlich model well, and the physical reaction made main contribution during adsorption-desorption process. The adsorption values （Kf-ads） of metsulfuron-methyl in 8 types of soil ranged from 0. 466 to 3. 219 mg^1-n·L^n/kg. The isotherms of 2^# soil resembled an S-type curve, while the isotherms of other types of soil resembled L-type isotherm. The results of desorption indicated that the hystersis phenomena appeared during the desorption process, and the hystersis coefficient（H）of the herbicides in the 8 soils studied varied from 0. 167 to 0. 670. Furthermore, Kf-ads and desorption values （Kf-ads） increased with increasing OM% and clay content, and decreased with increasing soil pH. Average hysteresis coefficient （Ha） decreased with increasing OM% and clay content and increased with increasing soil pH. It was concluded that the adsorption of metsulfuron-methyl in the test soils was low and un-reversible adsorption existed in the process, which would induce the substantial shift of the herbicide after being applied in the field. It could move to the underground or to underground water, thus imposing risks to the environment. Physical and chemical properties of soils, including OM%, clay content and pH of soil, were the dominating factors during the adsorption-desorption.

关 键 词： 甲磺隆 吸附 解吸 模型 滞后现象 土壤理化性质

领　　域： [农业科学] [农业科学]