TY - JOUR ID - 21034 TI - Kinetics of Nonexchangeable Potassium Release from Soils by Sodium Tetraphenylboron method JO - Iranian Journal of Soil and Water Research JA - IJSWR LA - en SN - 2008-479X AU - Shahbazi, Karim AU - Bazargan, Kambiz AD - Y1 - 2010 PY - 2010 VL - 41 IS - 1 SP - EP - KW - . KW - Kinetic equations KW - kinetics KW - potassium release KW - Sodium Tetraphenylboron DO - N2 - Nonexchangeable soil-K release rate can significantly affect K dynamics and it's bioavailability during plant growth. In this study, twelve soil samples taken from different wheat cropping regions of Iran were incubated with NaBPh4 to (i) investigate the kinetics of nonexchangeable K release and (ii) to compare the ability of various kinetic equations (zero-, first- and second-order, parabolic diffusion, simplified Elovich and power function) to describe nonexchangeable K release. Results revealed that potassium release was initially rapid followed by a slower rate. Almost 80% of total released soil-K after a time passage of 192h occurred in the first 48hs. The portion of soil total K that was released by NaBPh4 during the 8 day incubation period varied between 12.8 and 55.8% in different soils. NaBPh4-extracted K in a 5min period was highly correlated with NH4OAc- extracted K (r2=0.78, p UR - https://ijswr.ut.ac.ir/article_21034.html L1 - https://ijswr.ut.ac.ir/article_21034_ff2aba444334125649d5eab5691bfba9.pdf ER -