【摘要】 茶树具有喜酸聚铝特性,而酸性条件下土壤中的磷很容易被固定。为了弄清茶树根际土壤磷的吸附过程与作用机理,采用外源磷吸附培养方法,研究了不同母质、不同种植年限茶树根际土壤磷的吸附过程与动力学,并用最小二乘法进行Langmuir等温吸附方程拟合磷吸附动力学曲线,探讨了茶树根际土壤的磷吸附特征。结果表明:茶树根际土壤与非根际土壤磷的吸附过程与动力学有明显的差异。与非根际土壤的相比,茶树根际土壤最大吸附量(Xm)值低56 mg/kg,但是最大缓冲容量(MBC)高2.60,磷吸附饱和度(DPS)高1.44,表明根际土壤磷吸附力显著低于非根际土壤,而磷生物有效性高于非根际土壤。3种成土母质发育的茶园根际土壤磷吸附能力强弱依次为第四纪红色粘土>花岗岩风化物>板页岩风化物。随着种植年限的延长,根际土壤磷吸附能力特征值Xm和MBC有所降低,而DPS有所增加。第四纪红色粘土、花岗岩风化物和板页岩风化物3种母质发育的茶树根际土壤DPS值依次提高了0.83、2.83和3.51,而Xm依次降低了91 mg/kg,131 mg/kg和61 mg/kg。更多还原

【Abstract】 Characteristics of tea tree favor with accumulation aluminum and acid environment,and phosphorus is very easy to be fixed in acidic soil. In order to explore the phosphorus adsorption processes and reaction mechanism in tea rhizosphere soil,the culture experiment of adding phosphorus was carried out collecting tea rhizosphere soil of different parent materials and planting time in 2011. The phosphorus adsorption processes and its kinetics were studied,the characteristics of adsorption was discussed using the methods of the Langmuir isotherm adsorption curve which was simulated with the least squares method. The results showed that the clear differences of phosphorus adsorption process and dynamics were observed between tea tree rhizosphere soil and non-rhizosphere soil. Compared to non-rhizosphere soil,the maximum phosphate adsorption( Xm) decreased by 56 mg /kg,while the increment of both the maximum buffer capacity( MBC) and the Degree of phosphorus saturation( DPS) was 2. 60 and 1. 44 in tea rhizosphere soil,respectively. These results suggested that the phosphorus adsorption ability was lower and the phosphorus bioavailability is higher in tea rhizosphere soil than the non-rhizosphere soil. The order of the phosphorus adsorption ability was Quaternary red clay > Granite > the Slate in tea rhizosphere soil which derived different parent material. The DPS of rhizosphere soil was increased,but the MBC and Xmwere decrease. with the increase of the planting years. The increment of DPS in turn ware 0. 83,2. 83 and 3. 51,while the Xmdecreased by 91 mg /kg,131 mg / kg and 61 mg / kg in three kind parent material rhizosphere soil that were Quaternary red clay,Granite and the Slate.更多还原