Researchers studied how different levels of cadmium, moisture regimes, and incubation times affect the chemical forms of cadmium in two types of calcareous soils. They found that most of the cadmium was in water-soluble and iron-manganese oxide forms, with flooding decreasing water-soluble cadmium and increasing other forms. Clay soil had higher residual cadmium, while sandy clay loam had higher water-soluble-exchangeable, carbonate, and organic matter forms. Iron-manganese oxide forms were similar in both soils under field capacity. Flooding decreased water-soluble cadmium and increased other forms. Oxidizing and reducing conditions did not significantly affect residual and organic matter forms in the soils.