The Nature of Phosphorus in Calcareous Soils

Abstract

Calcareous soils (containing free lime) are common in many arid and semi-arid regions\nof North America and occur as inclusions in more humid regions. Phosphorus\n(P) is very reactive with lime. Following fertilizer application, P undergoes a series of\nreactions that gradually reduce its solubility. In most calcareous soils, there does\nnot appear to be a strong agronomic advantage of any particular P source when\nmanaged properly. Organic matter can inhibit P fixation reactions to some extent.\nSome fertilizer recommendations call for additional P to be added when the soil\ncontains high amounts of free lime.