Phosphorus availability in chicken manure is lower with increased stockpiling period, despite a larger orthophosphate content

• Published in: Plant and soil 2013-12, Vol.373 (1-2), p.359-372
• Main Authors: Peirce, C. A. E, Smernik, R. J, McBeath, T. M
• Format: Article
• Language: English
• Subjects: Acid soils; Agricultural soils; Agrology; Agronomy. Soil science and plant productions; Animal waste; Animal, plant and microbial ecology; application rate; Bioavailability; Biological and medical sciences; biomass; Biomedical and Life Sciences; chemical speciation; Chickens; Composted manure; Ecology; EDTA (chelating agent); Environmental aspects; farms; Fertilizers; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; greenhouses; isotope dilution technique; Life Sciences; Manure; manure storage; Manures; Mineral fertilizers; NMR; Nuclear magnetic resonance; nuclear magnetic resonance spectroscopy; nutrient uptake; Organic soils; orthophosphates; Other nutrients. Amendments. Solid and liquid wastes. Sludges and slurries; Phosphates; Phosphorus; Phosphorus content; Physiological aspects; phytic acid; Plant Physiology; Plant Sciences; Plants; poultry; Poultry farming; Poultry manure; Regular Article; shoots; Sodium hydroxide; soil; Soil Science & Conservation; Soil sciences; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Soils; Speciation; wheat
• ISSN: 0032-079X; 1573-5036
• DOI: 10.1007/s11104-013-1807-9

BACKGROUND AND AIMS: The relative proportions of phosphorus (P) forms present in manure will determine the overall availability of manure P to plants; however, the link between the forms of P in manures and manure P availability is unclear. This study compares the bioavailability and P speciation of three manures of different stockpiling duration: less than 1 month, 6 months and 12 months; manures were collected concurrently from a single poultry farm. METHODS: Bioavailability to wheat in a glasshouse trial was measured using an isotopic dilution method with manure added at an application rate equivalent to 20 kg P ha⁻¹. Phosphorus speciation was measured by ³¹P nuclear magnetic resonance (NMR) spectroscopic analysis of NaOH-EDTA extracts of the manures. RESULTS: The addition of all manures significantly increased shoot biomass and P concentration, with the fresh manure having the greatest effect. Addition of the fresh manure resulted in the largest labile P pool, highest manure P uptake and manure P recovery, while the manure stockpiled for 12 months resulted in the lowest manure P uptake and manure P recovery. NMR analysis indicated that there was more monoester organic P, especially phytate, in manure stockpiled for shorter periods, while the proportion of manure P that was orthophosphate increased with stockpiling time. CONCLUSIONS: Together, these results imply that although the proportion of total P in the manures detected as orthophosphate was higher with longer stockpiling, only a fraction of this orthophosphate was plant-available. This suggests the availability of P from orthophosphate in manures decreases with longer stockpiling time in much the same way that P from orthophosphate in mineral fertilizer becomes less available in soil over time.