School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China.
School of Environment and Energy, South China University of Technology, Guangzhou Higher Education Mega Centre, Guangzhou, 510006, PR China; School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, PR China.
J Environ Manage. 2024 May;358:120883. doi: 10.1016/j.jenvman.2024.120883. Epub 2024 Apr 16.
Applying organic fertilizer is the main way to enhance soil fertility through the interfacial reaction between mineral and dissolved organic matter (DOM). However, the interfacial reaction between minerals and DOM may influence antimony(V) (Sb(V)) mobility in agricultural soils around antimony mines. In our study the ferrihydrite (Fh) was chosen as a representative mineral, to reveal the effect of its interaction with chicken manure organic fertilizer (CM-DOM) with Fh on Sb(V) migration. In this study, we investigated different organic matter molecular weights and C/Fe molar ratios. Our findings indicated that the addition of CM-DOM decreased the adsorption of Sb(V) by Fh and promoted the re-release of Sb(V) adsorbed on Fh. This effect was enhanced by increasing the C/Fe molar ratio. Fh mainly affects its interaction with Sb(V) through electrostatic gravitational interaction and ligand exchange, but the presence of CM-DOM weakens the electrostatic interaction between Fh and Sb(V) as well as competes with Sb(V) for the hydroxyl reactive site on Fh surface. In addition, the smaller molecular weight fraction (<10 kDa) of CM-DOM has higher aromaticity and hydrophobicity, which potentially leads to more intense competition with Sb(V) for the reaction sites on Fh. Therefore, the application of organic fertilizer may promote Sb(V) migration, posing significant risks to soil ecosystems and human health, which should be a concern in field soil cultivation.
施用有机肥是通过矿物和溶解有机质（DOM）之间的界面反应来增强土壤肥力的主要方式。然而，矿物和 DOM 之间的界面反应可能会影响锑矿周围农业土壤中五价锑（Sb(V)）的迁移性。在我们的研究中，选择了针铁矿（Fh）作为代表性矿物，以揭示其与鸡粪有机肥（CM-DOM）与 Fh 相互作用对 Sb(V)迁移的影响。在本研究中，我们研究了不同有机物质分子量和 C/Fe 摩尔比。我们的研究结果表明，CM-DOM 的添加降低了 Fh 对 Sb(V)的吸附，并促进了 Fh 上吸附的 Sb(V)的重新释放。C/Fe 摩尔比的增加增强了这种效果。Fh 主要通过静电引力和配体交换作用影响其与 Sb(V)的相互作用，但 CM-DOM 的存在削弱了 Fh 和 Sb(V)之间的静电相互作用，并与 Sb(V)竞争 Fh 表面的羟基反应位点。此外，CM-DOM 的较小分子量部分（<10 kDa）具有更高的芳香度和疏水性，这可能导致与 Fh 上的反应位点更激烈的竞争。因此，有机肥的应用可能会促进 Sb(V)的迁移，对土壤生态系统和人类健康构成重大风险，这应该是田间土壤种植中需要关注的问题。
