Development of the Market for Direct Application Phosphate Rock--A Perspective Based on Experience in New Zealand and Scotland

摘要

Both Quinphos Fertilizers (NZ) Ltd. [now Summit-Quinphos (NZ) Ltd.] and Scotphos of Scotland were set up specifically to import direct application phosphate rock (DAPR) and sell blends of this with other nutrients. The formation of Summit-Quinphos wasa consequence of the senior author's involvement in the New Zealand Ministry of Agriculture 6-year "National Series" of trials comparing DAPR with soluble phosphate on permanent pasture (which compromises 90% of agricultural land in New Zealand). The trials demonstrated that DAPRs [specifically those in which at least 30% of the total P is soluble in citric acid in the product as sold, referred to as reactive phosphate rock (RPR) in New Zealand] eventually came to reach the performance of soluble P inthe majority of cases.