Abstract
Potassium supplying power by using Beckett approach to evaluate some criteria of potassium thermodynamics and its uses an indicators to evaluate soil fertility in some arid soils sampled from six locations of Nineveh Province in northern of Iraq. The results showed that soils were dominated with semictite and illite clay minerals. Regarding to Q/I ratio suggested by Beckett, the activity ratios values ranged from 119.48 - 300.69×10-3 mole.L-½, the labile pool of potassium values ranged from 38.82 - 104.61 c.mole.kg-1 ,where potassium potential buffering capacity values ranged from 0.15 - 0.80 c.mole.(kg.mole-1)-½. On the other hand Gibbs free energy -rG values were negatively spontaneous reaction were ranged from - 52.17 to - 29.51 cal..mole-1 and Gapon selectivity values fluctuated from the range 0.008 - 0.030 L.mole-1.
