Muhammad, H. J. and Jones, K. C. (1992) Phosphorus in gypsiferous soils: the influence of soil properties of P fractionation. Geoderma, 53 (1-2). pp. 97-104.
Full text not available from this repository.Abstract
This paper presents the results of a study into the status and distribution of P in six gypsiferous soil profiles collected from Iraq and southern Spain. A selective extraction procedure based on a modified version of that developed by Chang and Jackson was used. The concentrations of total P and the different inorganic P fractions declined with depth in all the soil profiles. The forms of the inorganic P fractions when expressed as a percentage of the total P decreased in the order: Ca-bound P reductant-extractable P > Al-bound P > Fe-bound P > organic P > NH4Cl-extractable P. There was little difference between profiles or horizons in this general pattern of distribution. The Ca-bound fraction ranged between 61.9 and 78.6% of the total P in different horizons. It is concluded that the behaviour of P in gypsiferous soils is dominated by its interactions with Ca supplied by gypsum.