摘要
研究了5个耕作土壤对钾素的选择与固定的特征。结果发现,以伊利石为主的土壤的交换选择性系数(K_G)及K_G趋于恒值时的交换性钾比率(EPR)均明显高于以高岭石为主的土壤,供试土壤的K_G与质地、物理性粘粒中的云母类矿物含量及固钾作用均有显著的相关性,表明土壤对钾索的交换选择性因质地、粘土矿物组成及物理性粘粒中云母类矿物含量的不同而有显著的差异,K_G的大小反映了土壤固钾作用的强度。
The characteristics of potassium exchange selectivity and fixation in 5 cultivated soils were studied.The results showed that Gapon coefficients (K_G) and the exchangeable potassium ratios (EPR) as K_G tended towards constant in illitic soils were much higher than those in kaolinitic soils.The K_G values were significantly correlated with the texture, contents of micaceous minerals in physical clays and potassium fixation in the soils used.These results indicated that the potassium exchange selectivities of soils were significantly different with the texture, composition of clay minerals and contents of micaceous minerals in the physical clays, and the K_G values could reflect the intensity of soil potassium fixation.
关键词
土壤
钾素
固钾作用
soil potassium
Gapon coefficient
clay minerals
micaceous minerals
potassium fixation
