奎屯垦区三种棉田土壤钾吸附、解吸动力学研究

【目的】研究新疆奎屯垦区棉田土壤钾吸附、解吸动力学性质和转化机制,为合理的钾肥施用提供理论依据。【方法】采用连续液流法研究奎屯垦区棉田3种土壤钾吸附、解吸动力学性质。【结果】3种土壤达到吸附、解吸平衡的时间均为:风沙土<草甸土<灰漠土。从吸附、解吸率达到90%以上所需的时间来看,钾的解吸过程快于吸附过程。在土壤钾的吸附、解吸反应中,相关系数以Elovich方程最高,其次为指数方程,抛物线扩散方程最低。【结论】草甸土对钾的吸附量大,在一定时间内解吸量大,说明草甸土供钾潜力大,供钾强度也较大。平衡前钾离子的吸附、解吸速率和吸附、解吸率与反应时间lnt间存在良好的线性关系。Elovich方程是描述奎屯垦区三种土壤钾的吸附和解吸过程的最优模型。

Study on Kinetics of Potassium Absorption-Desorption of Three Cotton Field Soils in Kuitun

【Objective】The properties of kinetics of the potassium absorption-desorption and the transform-ation mechanism of the cotton field soil in Kuitun was studied to provide reasonable basis for using potassium.【Method】The kinetics of the potassium absorption-desorption of the cotton field soil in Kuitun was studied by the continuous liquid flow technique methods.【Result】The time of the three soils going up to the equilibrating: aeolian sandy soil < meadow soil < grey desert soil.The time of K+ absorption-desorption percentage going up to 90% was compared,the K+ desorption reaction was faster than the absorption reaction.In the soil absorption and desorption reaction,the max of the correlation coefficient was elovich equation,next correlation coefficient was exponent equation,the min was parabolic diffustion equation.【Conclusion】The max quantity of potassium absorption was meadow soil and the quantity of potassium desorption was most in a certain extent,which indicated that meadow soil potential was most in providing the potassium and the provided the potassium intensity was most.There was a linear relationship between the potassium absorption-desorption velocity and reaction time lnt.Elovich equation was the best model for potassium absorption and desorption.