Abstract

In phytomanagement approach the application of a combination of amendments is an option for remediating arsenic polluted areas and valorized biomass obtained. Various amendments can be used. Biochar has been shown to reduce metal(loid) availability, and increase soil fertility, while iron sulfate has a considerable As binding capacity, and poultry manure is a source of nutrients. A phytotoxicity test was performed by applying the three amendments (2% biochar, 0.15%, 0.30% and 0.45% iron sulfate and 0.4% poultry manure) to a former tin mine technosol, to investigate their effects on (i) soil pore water properties, (ii) metal(loid) immobilization and (iii) Phaseolus vulgaris L. growth, used as a bioindicator. Biochar addition alone did not affect soil properties or plant parameters. However, the addition of iron sulfate acidified the soil, decreased soil pore water As concentrations, and increased the ones of Fe and Pb. It also improved plant growth, and reduced As and Pb aerial and root concentrations. Finally, the addition of poultry manure had no effect on soil and plants. Based on our results, the combination of iron sulfate with biochar may be a solution for reducing soil toxicity of the Abbaretz mining technosol, improving its fertility, and thus ameliorating plant growth.

• Novelty statement:

• The work presented in this manuscript describes the effect of amendment application, i.e., biochar, chicken dung and/or iron sulfate, on soil properties, metals availability and dwarf bean growth, plant used as bioindicator.

• Our results showed that the combination of a low amount of iron sulfate with biochar is the strategy to reduce soil toxicity, improved its fertility and consequently authorizes plant growth.

• This study is one of the first describing the effects of combined amendments on a mining soil properties with focusing on metal(loid) mobility.

摘要

在植物管理方法中，修正组合的应用是修复砷污染区域和获得的增值生物量的一种选择。可以使用各种修正。生物炭已被证明可以降低金属（液体）的可用性，并增加土壤肥力，而硫酸铁具有相当大的 As 结合能力，而家禽粪便是营养的来源。通过将三种添加物（2% 生物炭、0.15%、0.30% 和 0.45% 硫酸铁和 0.4% 家禽粪便）应用于前锡矿技术溶胶进行植物毒性测试，以研究它们对 (i) 土壤孔隙水特性的影响, (ii) metal (loid) 固定化和 (iii)菜豆L. 生长，用作生物指标。单独添加生物炭不会影响土壤特性或植物参数。然而，硫酸铁的添加使土壤酸化，降低了土壤孔隙水 As 浓度，增加了 Fe 和 Pb 的浓度。它还改善了植物生长，并降低了 As 和 Pb 的空气和根部浓度。最后，添加家禽粪便对土壤和植物没有影响。根据我们的研究结果，硫酸铁与生物炭的组合可能是降低 Abbaretz 采矿技术土壤毒性、提高其肥力从而改善植物生长的解决方案。

• 新颖性声明：

• 本手稿中介绍的工作描述了修正应用（即生物炭、鸡粪和/或硫酸铁）对土壤特性、金属可用性和矮豆生长、用作生物指示剂的植物的影响。

• 我们的结果表明，少量硫酸铁与生物炭的组合是降低土壤毒性、提高其肥力并因此促进植物生长的策略。

• 本研究是首次描述联合改良剂对采矿土壤性质影响的研究之一，重点是金属（液体）流动性。