Quantity-intensity ratio of potassium in gypsiferous soils in Iraq

ABSTRACT In gypsiferous soils, potassium (K) undergoes leaching, precipitation and other reactions that reduce its availability. This study aimed to evaluate the physicochemical behavior of K in soils Salahaddin province (Iraq), twelve locations chosen according variation their soil physical chemical properties. The adsorption phenomenon was described by using thermodynamic parameters quantity-intensity ratio (Q/I), with following results: equilibrium activity 16 48 x 10−5 (mol L−1 )1/2, total labile 19 80 10−3 cmolc kg−1, potential buffering capacity 22 42 kg−1 L−1)−1/2, free energy exchange -1.237 -1.086 kJ mol−1 Gapon selectivity coefficient 3.86 5.45 (L mol−1)1/2. All investigated are characterized good reserves, but low release.