Plant, Soil and Environment | |
Potassium release kinetics and its correlation with pinto bean (Phaseolus vulgaris) plant indices | |
Salehi M.H.:1  Motaghian H.R.1  Hosseinpur A.R.1  | |
关键词: parabolic diffusion; calcareous soils; kinetics equations; successive extraction; | |
DOI : | |
学科分类:农业科学(综合) | |
来源: Czech Academy of Agricultural Sciences | |
【 摘 要 】
The rate of potassium (K) release from soils is a dynamic process, and it is important to the evaluation of soil K availability to plant. The objectives of this study were to determine K release characteristics and the correlation of these parameters with bean plant indices in surface soils of 15 calcareous soils. The kinetics of K release was determined by successive extraction with 0.01 mol/L CaCl2 in a period of 2–2017 h at 25 ± 1°C. The results showed that the cumulative K release ranged from 111 to 411 mg/kg. A plot of cumulative amount of K released showed a discontinuity in slope at 168 h. Thus, two equations were applied to segments of the total reaction time (2 to 168 and 168 to 2017 h). The amounts of K released during 2–168 and 168–2017 h ranged from 55 to 299 and 44 to 119 mg/kg, respectively. Release kinetics of K conformed fairly well to parabolic diffusion, simplified Elovich and power function models in two segments. Potassium released after 2–168 and 168–2017 h and K release rate constants were significantly correlated (P < 0.05) with bean plant indices, while correlation between K extracted by using 1 mol/L NH4OAc (ammonium acetate) and plant indices was not significant. The results of this research showed that information obtained from K release studies in laboratory and kinetics equation parameters can help to estimate the K supplying power of soils.
【 授权许可】
Unknown
【 预 览 】
Files | Size | Format | View |
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RO201912010233350ZK.pdf | 454KB | download |