期刊名称：Pakistan Journal of Analytical & Environmental Chemistry
印刷版ISSN：1996-918X
电子版ISSN：2221-5255
出版年度：2021
卷号：22
期号：1
页码：74-83
DOI：10.21743/pjaec/2021.06.09
语种：English
出版社：National Centre of Excellence in Analytical Chemsitry
摘要：Potassium (K) availability to plants varies with the adsorption characteristics of soil, to evaluatethe adsorption capacity, five soil series of different characteristics were used. K adsorptionisotherms were performed by equilibrating 2.5 g soil samples with 10 levels of K (30-300 mg kg-1)as KCl in 0.01 CaCl2 solutions and shaken for 24 h at 25oC. The amount of K adsorbed rangedfrom 33.2 to 94.9% of added K. Freundlich model explained K adsorption behavior better than theother two equations. Higher coefficient of regression values 0.99, 0.97 and 0.96 were recorded inSultanpur (Silt loam), Naivela (Fine sandy loam) and Bhutesar (Clay loam), respectively. Thehighest 1/n value 1.54 kg mg-1 and kf value 31.47 mg kg-1 of Freundlich isotherm were observedin Sultanpur (silt loam) due to high pH, high OM and high clay contents, lowest values ofconstants were observed in Wajan (loamy sand) with 1/n value 0.44 kg mg-1 and kf value 0.28 mgkg-1 might be due to high EC, high CaCO3 and sand contents. The K adsorption of soil varied withphysico – chemical characteristics of soil, especially clay content, alkaline pH and organic mattercontent.
