Potentially toxic elements (PTEs) are widespread pollutants in agricultural fields, presenting significant challenges to the maintenance of soil ecological functions while simultaneously reducing their concentrations. This study detailed the development of a high-strength reusable silicate magnetic composite biochar sphere (SMBCS) characterized by superior magnetic and adsorption properties, synthesized from natural minerals and biochar. The application of SMBCS over three consecutive remediation cycles led to reductions in cadmium (Cd), lead (Pb), and arsenic (As) concentrations in soil by 28.6%, 26.6%, and 42.9%, respectively, accompanied by corresponding decreases in bioavailability of 52.7%, 49.4%, and 39.4%. The accumulation of Cd, Pb, and As in rice seedlings cultivated in the remediated soil decreased by 79.50–85.47%, 38.05–38.99%, and 39.56–77.10%, respectively. However, the removal of essential mineral nutrients (Al, Fe, K, Ca, Mg, Si, N, Zn, Mn, and Cu) from the soil ranged from 3.26% to 36.28%, which adversely affected seed germination and rice seedling growth. Pre-planting fertilization with rice straw (RS), pig manure (PM), biochar (RSB and PMB), and regenerated SMBCS (RSMBCS1 and RSMBCS2) effectively reduced Cd (0.20–45.40%) and Pb (8.70–35.36%) uptake while enhancing the bioavailability of mineral nutrients, thereby promoting crop growth and physiological traits. The SMBCS-fertilization technique emerges as a viable approach for the removal of PTEs in agricultural soils, facilitating the restoration of ecological functions and ensuring safe agricultural production.

中文翻译：

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使用稻草、猪粪及其衍生的生物炭，用可重复使用的生物炭颗粒对潜在有毒元素污染的土壤进行施肥


潜在有毒元素 （PTE） 是农业领域中广泛存在的污染物，对维持土壤生态功能提出了重大挑战，同时降低了其浓度。本研究详细介绍了由天然矿物和生物炭合成的高强度可重复使用硅酸盐磁性复合生物炭球 （SMBCS） 的开发，其特点是具有优异的磁性和吸附性能。在三个连续的修复周期中应用 SMBCS 导致土壤中的镉 （Cd）、铅 （Pb） 和砷 （As） 浓度分别降低了 28.6%、26.6% 和 42.9%，同时生物利用度也相应降低了 52.7%、49.4% 和 39.4%。在修复土壤中培育的水稻幼苗中 Cd、Pb 和 As 的积累量分别降低了 79.50–85.47%、38.05–38.99% 和 39.56–77.10%。然而，从土壤中去除必需的矿物养分（Al、Fe、K、Ca、Mg、Si、N、Zn、Mn 和 Cu）的含量为 3.26% 至 36.28%，这对种子发芽和水稻幼苗生长产生了不利影响。种植前施用稻草 （RS）、猪粪 （PM）、生物炭 （RSB 和 PMB） 和再生 SMBCS （RSMBCS1 和 RSMBCS2） 有效降低了 Cd （0.20-45.40%） 和 Pb （8.70-35.36%） 的吸收，同时提高了矿物养分的生物利用度，从而促进作物生长和生理特性。SMBCS 施肥技术成为去除农业土壤中 PTE 的可行方法，有助于恢复生态功能并确保农业安全生产。