EFFECT OF THE ANION ON THE SORPTION OF POTASSIUM BY SOME HUMIC AND HYDROL HUMIC LATOSOLS

Abstract

Percolation, conductometric and pot studies were made of the sorption of K from various salts by Hawaiian soils of the more humid region. Also studied were combinations of KC1 with several commonly used non-K fertilizers. Where individual salts were employed K was retained in the following order: KCl < K2SO4 < K phosphates. Leachability of K from KC1 was reduced by applying it together with (NH4)2SO4, or ammophos. Superphosphates were without effect. Differential sorption of K, retention of anions and failure to recover appreciable quantities of displaced cations point to a possible simultaneous sorption of cations and anions and indicate a process in which cation exchange plays a minor role, if any.