Seyed Ali Reza Movahedi Naeini - Soil Science Department,Gorgan University of Agricultural Sciences and Natural Resources,Gorgan,Iran
Faramarz Faeznia - Soil Science Department,Gorgan University of Agricultural Sciences and Natural Resources,Gorgan,Iran
Ahmad Yazdani - Animal Science Department,Gorgan University of Agricultural Sciences and Natural Resources,Gorgan,Iran

Structure, texture and chemical composition of natural zeolites are specifically important characteristics inducing ionic exchange, absorption and de-sorption of gas and liquids. Zeolites are widely used in agriculture and industry due to the abundance of rich sources and economic return. Zeolite effects on potassium adsorption isotherms and potential buffering capacity was investigated in a field trial in Gorgan Agricultural University estate, comparing N, P, K, P+K, zeolite and control treatments. Potassium adsorption isotherms were fitted with Freundlich, Langmuir and Initial Mass models. All three models fit potassium adsorption. Potassium potential buffering capacity was obtained using Q/I curves. Maximum potassium adsorption and potential buffering capacity obtained by zeolite treatment. Maximum wheat N and K uptake and yield was also with the zeolite treatment as a slow release source of these ions.

Zeolite, Adsorption isotherms, Potassium, Potential buffering capacity