Effect of soil pH and organic matter on desorption hysteresis of chlorimuron-ethyl in two typical Chinese soils
Effect of soil pH and organic matter on desorption hysteresis of chlorimuron-ethyl in two typical Chinese soils
复制标题
中国两种典型土壤土壤pH和有机质对氯嘧磺隆解吸滞后的影响
DOI：
10.1007/s11368-011-0337-4
复制
发表时间：
2011-02
影响因子：
3.6
通讯作者：
Zhou, Qixing
中科院分区：
文献类型：
--
作者：
Ren, Wenjie;Wang, Meie;Zhou, Qixing
氯嘧磺隆是一种磺酰脲类除草剂，广泛应用于一年生阔叶杂草的防除，长期残留对轮作作物或蔬菜造成严重危害。关于土壤pH值和有机质对氯嘧磺隆解吸过程的影响的知识仍然不清楚。本研究以中国东北地区的两种典型土壤--棕壤（淋溶土）和黑土（黑土）为研究对象，研究了氯嘧磺隆在土壤中的解吸行为及其与土壤pH和有机质的关系。用过氧化物处理土壤以除去有机物。模拟了氯嘧磺隆在原始土壤和H2 O2处理土壤中的解吸动力学。采用间歇平衡法，在3种不同pH值下，对3种有机质进行了吸附和解吸试验。对于去除有机质后的土壤，由于吸附浓度低于方法的检测限，因此未采用较低的吸附浓度进行解吸研究.结果与讨论伪二级动力学方程能很好地描述解吸动力学，去除有机质后土壤的解吸速率显著增加。解吸数据与Freundlich等温式拟合良好，回归系数较高（R2> 0.97）。此外，氯嘧磺隆在两种土壤中的解吸均存在明显的滞后现象，且由于黑土中有机质和粘粒含量较高，砂粒含量较低，氯嘧磺隆在黑土中的解吸作用弱于棕壤。随着初始浓度的增加，氯嘧磺隆从两种土壤中的解吸变得更加困难，这是浓度梯度效应的结果。滞后的程度增加，土壤pH值的增加，由于加强吸附相互作用的结合能。结论氯嘧磺隆从棕壤和黑土的解吸显着滞后，和滞后的程度是大于棕壤。土壤pH值的升高会增加氯嘧磺隆的滞留量，从而有效地阻止氯嘧磺隆进入水相。H2 O2去除有机质的方法不适合研究有机质对氯嘧磺隆在原土中解吸的影响。
PurposeChlorimuron-ethyl is a sulfonylurea herbicide widely used to control many annual broadleaf weeds, and the residue for a long period posed a heavy hazard to rotational crops or vegetables. Knowledge about effect of soil pH and organic matter on desorption processes of chlorimuron-ethyl remains obscure. In this study, desorption behavior of chlorimuron-ethyl as a function of soil pH and organic matter was investigated.Materials and methodsTwo typical soils in northeastern China, brown earth (luvisols) and black soil (phaeozem), were used in this study. Soils were treated with peroxide to remove organic matter. Desorption kinetics of chlorimuron-ethyl in the original and H2O2-treated soils were simulated. The adsorption and desorption experiments were conducted at three different pH values with the original soils using batch equilibration methods. For the soils after having removed organic matter, the lower concentrations of adsorption were not used for desorption study because the concentrations expected were lower than the limit of detection of the method.Results and discussionThe pseudo-second-order equation could well describe the desorption kinetics and the desorption velocity increased significantly from the soils after the removal of organic matter. The desorption data were well fitted with the Freundlich isotherm with high regression coefficients (R2> 0.97). Besides, the apparent hysteresis was observed for the desorption of chlorimuron-ethyl from the two soils, and the desorption from black soil was weaker than that from brown earth due to the higher content of organic matter and clay, and lower proportion of sand. The desorption of chlorimuron-ethyl from both soils became more difficult with an increase in the initial concentrations as a result of the gradient effect of concentrations. The degree of hysteresis increased as soil pH increased due to the strengthened binding energy of adsorption interactions.ConclusionsThe desorption of chlorimuron-ethyl from brown earth and black soil was significantly hysteretic, and the degree of hysteresis was greater for black soil than for brown earth. The increase of soil pH would enhance the retention of chlorimuron-ethyl and thus effectively retard chlorimuron-ethyl from entering the aqueous phase. The method of removing organic matter by H2O2treatment was not fit for researching effect of organic matter on the desorption of chlorimuron-ethyl from original soils.
登录
查看更多内容
影响因子：
12.8
作者：
J. P. Gao;J. Maguhn;P. Spitzauer;A. Kettrup
通讯作者：
J. P. Gao;J. Maguhn;P. Spitzauer;A. Kettrup
影响因子：
8.8
作者：
J. Joo;C. Shackelford;K. Reardon
通讯作者：
J. Joo;C. Shackelford;K. Reardon
影响因子：
5.7
作者：
Hong-jian Gao;Xin Jiang
通讯作者：
Hong-jian Gao;Xin Jiang
影响因子：
13.6
作者：
Lee, Sangjin;Pardue, J. H.;Kim, D. J.
通讯作者：
Kim, D. J.
影响因子：
2.4
作者：
Hyun, S;Lee, LS
通讯作者：
Lee, LS