Reduction in phosphorus availability in poultry and diary manure by mineral amendments

Abstract Phosphorus (P) loading of soils from the repeated application of manure and the associated loss of P to water systems is a serious and increasing problem in today's agricultural landscape. The hypothesis of this study was that the application of mineral amendments to manure might reduce P availability in manure and soil without affecting crop productivity. An incubation experiment was conducted to evaluate the ability of aluminum sulfate, ferric chloride or calcium hydroxide at 100 and 200 g kg−1 of manure to reduce phytoavailable (Mehlich-3 extractable) P in liquid dairy, laying hen and broiler chicken manure. Mehlich-3 extractable P was reduced from 59 to 97% in all manure treated with aluminum sulfate and ferric chloride. The calcium hydroxide treatment resulted in a Mehlich-3 extractable P reduction ranging from −17 to 51%. A container experiment was then carried out to examine the effect of soil with pre-treated manure on timothy (Phelum pretense L.) growth and soil P levels. Timothy yields ...