fate of phosphorus of ash-rich biochars in a soil-plant system

• Published in: Plant and soil Vol. 375; no. 1-2; pp. 61 - 74
• Main Authors: Wang, Tao, Camps-Arbestain, Marta, Hedley, Mike
• Format: Journal Article
• Language: English
• Published: Cham Springer-Verlag 01.02.2014; Springer; Springer International Publishing; Springer Nature B.V
• Subjects: Acid soils; Agricultural and Veterinary sciences; Agricultural Sciences; Agricultural soils; Agrology; Agronomy. Soil science and plant productions; Animal, plant and microbial ecology; Annan lantbruksvetenskap; application timing; Bioassays; Bioavailability; Biochar; Biological and medical sciences; Biomedical and Life Sciences; Biosolids; calcium; Cattle manure; Charcoal; Ecology; Environmental aspects; Fertilizers; Flowers & plants; Forest soils; Fractionation; Fundamental and applied biological sciences. Psychology; General agronomy. Plant production; Lantbruksvetenskap och veterinärmedicin; Life Sciences; Other Agricultural Sciences; Phosphorus; Phosphorus content; phosphorus fertilizers; Plant Physiology; Plant Sciences; Plant-soil relationships; Plants; Regular Article; rock phosphate; Sand soils; Sandy soils; slow-release fertilizers; Sodium hydroxide; Soil pollution; Soil research; Soil Science & Conservation; Soil treatment; Soil-plant relationships. Soil fertility; Soil-plant relationships. Soil fertility. Fertilization. Amendments; Soils; New Zealand; Transformation; Bioavailability; Biochar; P fractionation; Carbonization; Fractionation; Phosphorus; Soil plant relation; Biological system
• ISSN: 0032-079X; 1573-5036; 1573-5036
• DOI: 10.1007/s11104-013-1938-z

AIMS: The objectives were to investigate (i) the forms and release pattern of P from an ash-rich biochar-amended sandy soil; (ii) the transformation of biochar P in a soil-plant system. METHODS: Several methodologies (a bioassay test, soluble P extractions, a sequential P fractionation and successive P extractions via resin strips) were used to study the bioavailability and transformation of P in a sandy soil fertilised with either conventional P fertilisers [Ca(H₂PO₄)₂ (CaP) and Sechura phosphate rock (SPR)] or biochars produced from cattle manure (MAe) and alum-treated biosolids (BSe) at four temperatures (250, 350, 450, and 550 °C). RESULTS: Biochar P mainly contributed to increase soil resin-extractable P- and inorganic NaOH-extractable P-fractions, and thus to plant available P. The decrease in P concentrations of those fractions was caused by the uptake of P by plants rather than their transformations into more stable forms. P release rates diminished following the order: CaP > MAe > BSe > SPR, which indicates a decline in P availability from these P sources. CONCLUSIONS: Phosphorus-rich biochar can be used as a slow-release fertiliser. It is necessary to determine available P (either soil or fertiliser tests) in biochars prior to its application to soil, so that dose, frequency and timing of application are correctly established.