Abstract:

In order to ensure food security in developing countries, there is a need for the sustainable
intensification of agricultural production systems towards supporting productivity gains and
income generation. In this context, novel, soil-specific technologies will have to be developed,
pilot tested and transferred to farmers in a relatively short time. Phosphorus (P) is an essential
nutrient element for plants and animals. The appropriate and sound utilization of phosphate
rocks (PRs) as P sources can contribute to sustainable agricultural intensification, particularly
in developing countries endowed with PR resources.
PR is a general term used to describe phosphate-bearing minerals. PR is a finite, nonrenewable natural resource. Geological deposits of different origin are found throughout the
world. Currently, few PR deposits are mined, and about 90 percent of world PR production is
utilized by the fertilizer industry to manufacture P fertilizers, with the remainder being used to
manufacture of animal feeds, detergents and chemicals. However, many PR deposits located
in the tropics and subtropics have not been developed. One reason is that the characteristics of
these PRs, though suitable for direct application, do not meet the quality standards required for
producing water-soluble P (WSP) fertilizers using conventional industrial processing technology.
Another reason is that the deposits are too small to warrant the investment needed for mining
and processing. On a worldwide basis, there is ample supply of high-quality PRs for chemical
processing and direct application for the foreseeable future