【作者】 金彩霞；

【导师】 周启星；

【作者基本信息】 中国科学院研究生院（沈阳应用生态研究所） ， 生态学， 2006， 博士

【摘要】 Cd和豆磺隆是黑土区比较典型的两种化学污染物,通过开展水-土界面Cd迁移试验、根-土界面Cd吸附-解吸试验、根-土界面Cd化学形态变化动力学试验及Cd-豆磺隆联合胁迫生物化学反应动力学试验,对Cd在Cd-豆磺隆污染黑土多介质界面过程及化学动力学进行了研究,为黑土区Cd和豆磺隆污染防治提供理论依据。pH对水-土界面Cd扩散和吸附过程产生明显的影响,一般是在酸性条件下,比较有利于Cd在水-土界面的迁移,在碱性条件下,其迁移能力明显降低。豆磺隆影响水-土界面Cd迁移行为,且对水-土界面和土-水界面Cd迁移行为产生影响的结果不同。Elovich方程和双常数方程分别是描述根-土界面Cd吸附和解吸的最优动力学方程。根-土界面Cd吸附量大于非根-土界面Cd吸附量,而解吸时的情况与此相反。豆磺隆对Cd的吸附和解吸都表现出抑制作用。小麦体内Cd积累量随着土壤中Cd浓度的增加而增加,豆磺隆抑制Cd的吸收,Cd-豆磺隆在小麦体吸Cd过程中表现出拮抗效应。根-土界面各层碳酸盐和铁锰结合态Cd可向可交换态Cd转化,且这种转化趋势由根中心区向根外区减弱,而向残留态Cd转化的趋势加强,近根层的可交换态Cd和有机结合态Cd是小麦能直接利用的两种Cd形态。Cd-豆磺隆复合污染对脲酶表现出拮抗效应,而对过氧化氢酶和酸性磷酸酶则有一定的协同效应。更多还原

【Abstract】 Cadmium and chlorimuron-ethyl (CE) are two typical pollutants in phaiozem. Through carrying out the experiments of Cd-transferring behaviors between water-soil interfaces, sorption/desorption behaviors and chemical dynamics of Cd between root-soil interfaces and biochemical dynamics of Cd-CE, in particular, multimedium interface processes and chemical dynamics in phaiozem polluted by Cd and CE were studied, aiming to provide theoretical references for the prevention and treatment of Cd and CE pollution in the phaiozem area.Diffusion and sorption processes of Cd between water-soil interfaces were obviously affected by pH, and Cd2+ transferred more quickly in acidic solution than in alkaline solution. CE could affect the Cd transferred action, but Cd transferred action affected by pH between water-soil or soil-water interface was different.The best models for Cd2+ sorption/desorption kinetics were Elovich equation and two-constant equation, respectively. The amount of Cd sorbed on root-soil interfaces was much higher than that on non-root-soil interfaces, but it was on the contrary when Cd was desorbed. CE could restrain the sorption and desorption of Cd.The quantity of Cd absorbed by wheat plants increased with increasing soil Cd, and which was affected by CE. There was antagonistic interaction between Cd and CE in the process of absorbing Cd by wheat plants. The trend of carbonate-bound Cd and Fe-Mn oxide-bound Cd transformed to exchangeable Cd was weakened from root-center zone to non-rhizosphere, but the trend of two Cd forms transformed to residual Cd was strengthened. The result of correlation suggested that exchangeable Cd and organic-bound Cd nearby the root were the main Cd forms that could be absorbed by wheat. There was antagonistic interaction to the activity of urease, but shown synergistical effect to the activity of CAT and acidic phosphate.更多还原