K-Dynamics in a Continuously Submerged Limed and the Corresponding Unlimed Soil Subjected to One and Two Cycles of Drying Phase

摘要

A laboratory experiment was carried out to study the effect of drying phases on transformation of different fractions of K in submerged limed and the corresponding unlimed soil in presence and absence of N and K fertilizers. Changes in different fractions of K were monitored with time. Results showed that irrespective of treatments, available K increased in the limed soil throughout the period of incubation. However, non-exchangeable K showed an exactly opposite trend of results particularly in limed situation indicating a dynamic equilibrium between these forms of K in soils. Although, the trend of results of both available and non-exchangeable forms are totally different in unlimed situation. The decrease in 1N boiling HNO3 extractable K is comparatively more in limed soil subjected to single drying phase. No drastic variation in lattice and total K is observed under different treatment combinations. It indicates, maintenance of drying phase has little effect on lattice and total K in soils.