狼尾草根系分泌物对黑土吸附阿特拉津的影响研究

采用批量平衡试验方法,研究狼尾草根系分泌物对黑土吸附阿特拉津的影响.结果用Evolich方程(R2>0.97)和准二级动力学模型(R2>0.99)进行拟合,两者都表现出较好拟合度.用Langmuir和Freundlich等温吸附方程描述土壤吸附阿特拉津的过程,其中,Freundlich方程拟合结果较好(R2>0.91),而Langmuir方程中R2<0.60,加入狼尾草根系分泌物后,吸附平衡常数Kf明显减小,参数1/n增大到1左右,属于较难吸附,表明狼尾草根系分泌物对阿特拉津可能有抑制作用,且根系分泌物浓度不同,影响程度不同.

Effect of Pennisetum Root Exudates on Adsorption of Atrazine on Soil

The method of mass balance test was used to study the effects ofroot secretion of Black soil adsorption of atrazine. The laboratory dataare fitted with Evolich Equation(R2 >0. 97)and the pseudo-second-order model(R2 >0. 99). Both of them showed good fittings. The soil adsorption process of atrazine can be described by Langmuir and Freundlich isothermal adsorption e-quations. Compared with each other, the fitting of Freundlich equation showeda good effect(R2 >0. 91), but in Langmuir equa-tion, R2 <0. 60. Afteraddedpenniseetum root secretion, the adsorption equilibrium constant significantly reduces, the parameter 1/n increases to about 1, belonging to the hard degree of adsorption. The results show that penniseetum root secretionof Black soil adsorption of atrazinemay have inhibitory effect, and different concentrations of root secretionhave different influence degrees.