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Phosphorus Distribution in Soils Treated with Bioenergy Co-product Materials following Corn Growth
- Pagliari, Paulo H., Strock, Jeffrey S., Johnson, Jane M. F., Waldrip, Heidi M.
- Agronomy journal 2018 v.110 no.3 pp. 850-858
- Panicum virgatum, Zea mays, agricultural soils, best management practices, biochar, bioenergy, coproducts, corn, corn cobs, enzymatic hydrolysis, fertilizers, fractionation, gasification, hydrochloric acid, inorganic phosphorus, poultry manure, pyrolysis, recycling, sodium bicarbonate, sodium hydroxide, soil sampling, triple superphosphate, Minnesota
- This research was conducted to investigate the impact of corn cob gasification biochar (CCGB), switchgrass pyrolysis biochar (SPB), turkey manure ash (TMA), and triple superphosphate fertilizer (TSP) on soil phosphorus (P) distribution in three agricultural soils from Minnesota, USA. Understanding how biochar can change soil P distribution is crucial to develop best management practices for recycling biochar products. Phosphorus sources were incorporated at rates of 0, 28, 56, and 84 mg P₂O₅ kg–¹ to 1.5 kg of each soil in 2-L pots. Corn (Zea mays L.) plants were grown (2 plants pot–¹) in treated soils for 56 d after emergence. After 56 d, plants were harvested and soil samples collected for sequential P fractionation (H₂O, 0.5 mol L–¹ NaHCO₃, 0.1 mol L–¹ NaOH, and 1.0 mol L–¹ HCl) and enzymatic hydrolysis. The results of the sequential fractionation showed that CCGB and SPB were as effective as TSP and TMA at increasing total P extractable in water and HCl. In contrast, the increase in NaHCO₃ and NaOH extractable total P was higher with TSP and TMA than with the CCGB and SPB. In most cases, the increase in inorganic P was similar between biochar and TSP, suggesting that biochar could supply equal amounts of plant available P as commercial fertilizer. The effects of biochar on enzymatically hydrolysable P were not consistent and varied by soil. In conclusion, the results of this study showed that biochar has potential to increase the available P pools in soils similar to commercial fertilizer.