Abstract

The presence of Ni above the permissible limit in agriculture soils poses negative effects on soil health, crop quality, and crop productivity. Surprisingly, the usage of various organic and inorganic amendments can reduce Ni mobility in the soil and its distribution in the crops. A pot experiment was conducted to elucidate the effects of olive pulp biochar (BR), calcite (CAL), and wheat straw (WS), as sole amendments and their mixtures of 50:50 ratio, added to Ni polluted soil on Ni mobility in the soil, Ni immobilization index (Ni − IMi), soil enzymatic activities, Ni distribution in parts of chili plant, Ni translocation factor and bioaccumulation factor in fruit, plant growth parameters and oxidative stress encountered by the plants. Outcomes of this pot experiment revealed that amendments raised soil pH, improved soil enzymatic activities, values of Ni − IMi, while significantly reduced bioavailable Ni fraction in the post-harvest soil. However, the highest activities of acid phosphatase, urease, catalase, and dehydrogenase by 50, 70, 239, and 111%, respectively, improvement in Ni − IMi up to 60% while 60% reduction in the bioavailable Ni fraction was observed in BR + CAL treatment, compared to control was noted. Among all amendments, the top most reduction in Ni concentrations in shoots, roots, fruit, Translocation Factor (TF), and Bioaccumulation Factor (BAF) values of fruit by 72%, 36%, 86%, 72%, and 86%, in BR + CAL treatment, compared to control. Moreover, the plants growing on BR + CAL amended Ni contaminated soil showed the topmost improvement in plant phonological parameters while encountered the least oxidative stress. Such findings refer to the prospective usage of BR + CAL at 50:50 ratio than BR, CAL, WS alone, and BR + WS as well as WS + CAL for reducing Ni mobility in the soil, improving Ni − IMi, soil enzymatic activities, plant phonological and oxidative stress while reducing Ni distribution in plant parts.

Novelty statement

In this experiment, it was hypothesized that amending Ni polluted soil with olive pulp biochar (BR), CAL, and WS as alone soil amendments and their combinations at 50:50 ratios can reduce Ni bioavailability in soil, Ni distribution in chili plant and oxidative stress encountered by the plants. Moreover, these amendments may improve, soil enzymatic activities, Ni immobilization index, plant phenological traits. Therefore, it was aimed to undertake useful scientific planning and research, to restore and rehabilitate the dwellings, biological resources and to minimize the sufferings of the peoples in nutrient-poor Ni contaminated soils, by improving soil health and chili productivity.

摘要

农业土壤中 Ni 含量超过允许限度会对土壤健康、作物质量和作物生产力造成负面影响。令人惊讶的是，使用各种有机和无机改良剂可以降低土壤中镍的迁移率及其在农作物中的分布。进行盆栽试验以阐明橄榄果肉生物炭 (BR)、方解石 (CAL) 和麦秸 (WS) 作为唯一的改良剂及其 50:50 比例的混合物添加到镍污染土壤中对镍迁移率的影响。土壤、Ni 固定指数（Ni-IMi）、土壤酶活性、辣椒植株部分 Ni 分布、果实中 Ni 转运因子和生物蓄积因子、植物生长参数和植物遇到的氧化应激。这个盆栽实验的结果表明，改良剂提高了土壤的 pH 值，改善了土壤酶活性，Ni - IMi 的值，同时显着降低收获后土壤中的生物可利用 Ni 分数。然而，酸性磷酸酶、脲酶、过氧化氢酶和脱氢酶的最高活性分别提高了 50%、70%、239% 和 111%，在 BR 中观察到 Ni-IMi 提高了 60%，而生物可利用 Ni 分数降低了 60% + CAL 治疗，与对照相比，注意到了。在所有修正中，新芽、根、果实、易位因子 (TF) 和果实生物蓄积因子 (BAF) 值的 Ni 浓度降低幅度最大，分别降低了 72%、36%、86%、72% 和 86%，在 BR + CAL 治疗中，与对照相比。此外，在 BR + CAL 修正的 Ni 污染土壤上生长的植物在植物语音参数方面表现出最大的改善，而受到的氧化胁迫最少。

新颖性声明

在本实验中，假设用橄榄果肉生物炭 (BR)、CAL 和 WS 作为单独的土壤改良剂及其 50:50 比例的组合来改良 Ni 污染的土壤可以降低土壤中 Ni 的生物有效性、辣椒植物中的 Ni 分布和氧化性。植物遇到的压力。此外，这些改良剂可能会改善土壤酶活性、Ni 固定指数、植物物候性状。因此，它的目的是进行有益的科学规划和研究，通过改善土壤健康和辣椒生产力，恢复和恢复住宅、生物资源，并尽量减少人们在营养贫乏的镍污染土壤中的痛苦。