Department of Soil Science, Faculty of Agricultural Sciences and Technology, Bahauddin Zakariya University, Multan, Pakistan.
Department of Plant Biotechnology, Atta-ur-Rahman School of Applied Biosciences (ASAB), National University of Sciences and Technology (NUST), Islamabad, Pakistan.
Chemosphere. 2021 Mar;266:128980. doi: 10.1016/j.chemosphere.2020.128980. Epub 2020 Nov 19.
Phosphorous (P) fixation in alkaline calcareous soils is a serious concern worldwide and acidified-biochar application has been proposed to improve the agronomic benefits of applied P. The present study aims to improve understanding of P transformation process in an alkaline soil following different biochar amendments (rice-husk biochar (RHB), sugarcane-bagasse biochar (SWB) and wheat-straw biochar (WSB)), chemically engineered (acidification with 1 N HCl or washing with distilled water (pristine biochar)) along with or without P at 60 mg kg. A pot experiment was conducted with three biochars (RHB, SWB, WSB) and control, two chemical modifications (acidic and pristine), and two P-levels (without or with P). A pot study by growing spring maize and a parallel incubation study were done to test the treatment effects on P transformation. Results demonstrated that acidified SBC and WSB increased the plant P uptake and dry-matter yield by 40% and 29.7%, respectively, with P-supply. Both pristine or acidified RHB produced 80.5% and 110.7%, more root dry-matter, respectively, compared to respective controls without P. Non-acidified WSB along with P showed significantly higher Olson's P in incubation study. While in case of acidification along with P addition, RHB exhibited greater P availability, but it was inconsistent at different times during incubation. It can be concluded that acidified biochar amendments have potential to improve P management with inconsistent results. It is difficult to rule out that acidification of biochars is a pre-requisite for alkaline soils for P improvement. Further research is needed to explore site-specific P management for sustainable crop production.
磷（P）在碱性钙质土壤中的固定是一个全球性的严重问题，酸化生物炭的应用被提议用来提高施入 P 的农业效益。本研究旨在通过不同生物炭改良（稻壳生物炭（RHB）、甘蔗渣生物炭（SWB）和小麦秸秆生物炭（WSB）），以及在 60mgkg 条件下施加或不施加 P 时，改善对碱性土壤中 P 转化过程的理解。进行了一项盆栽实验，涉及三种生物炭（RHB、SWB、WSB）和对照、两种化学修饰（酸化和原始）以及两种 P 水平（无 P 或有 P）。通过种植春玉米进行盆栽研究，并进行平行培养研究，以测试处理对 P 转化的影响。结果表明，酸化的 SBC 和 WSB 分别在施加 P 的情况下，使植物 P 吸收量和干物质产量增加了 40%和 29.7%。原始或酸化的 RHB 与各自无 P 的对照相比，分别产生了 80.5%和 110.7%更多的根干物质。在培养研究中，未经酸化的 WSB 与 P 一起表现出明显更高的奥尔森 P。然而，在酸化和添加 P 的情况下，RHB 表现出更高的 P 有效性，但在培养过程中的不同时间不一致。可以得出结论，酸化生物炭改良有可能改善 P 管理，但结果不一致。很难排除生物炭的酸化是碱性土壤改善 P 的前提条件。需要进一步研究以探索特定地点的 P 管理，以实现可持续的作物生产。
