INDUROT and Environmental Biogeochemistry and Raw Materials Group, University of Oviedo, Mieres, Spain; Department of Organisms and Systems Biology, University of Oviedo, Mieres, Asturias, Spain.
Department of Plant Biology and -Soil Science, Área de Edafoloxía e Química Agrícola, Facultade de Ciencias, Universidade de Vigo, 32004 Ourense, Spain; Instituto de Agroecoloxía e Alimentación (IAA), Campus Auga, Universidade de Vigo, 32004 Ourense, Spain.
Sci Total Environ. 2024 Jun 20;930:172451. doi: 10.1016/j.scitotenv.2024.172451. Epub 2024 Apr 18.
Here we addressed the capacity of distinct amendments to reduce arsenic (As), copper (Cu), selenium (Se) and zinc (Zn) associated risks and improve the biogeochemical functions of post-mining soil. To this, we examined nanoparticles (NPs) and/or biochar effects, combined with phytostabilization using Lolium perenne L. Soil samples were taken in a former metal mine surroundings. Ryegrass seeds were sown in pots containing different combinations of NPs (zero-valent iron (nZVI) or hydroxyapatite (nH)) (0 and 2 %), and biochar (0, 3 and 5 %). Plants were grown for 45 days and the plant yield and element accumulation were evaluated, also soil properties (element distribution within the soil fractions, fertility, and enzymatic activities associated with microbiota functionality and nutrient cycling) were determined. Results showed biochar-treated soil had a higher pH, and much higher organic carbon (C) content than control soil and NP-treated soils, and it revealed increased labile C, total N, and available P concentrations. Soil treatment with NP-biochar combinations increased exchangeable non-acid cation concentrations and reduced exchangeable Na%, improved soil fertility, reduced sodicity risk, and increased ryegrass biomass. Enzymatic activities, particularly dehydrogenase and glucosidase, increased upon the addition of biochar, and this effect was fostered by NPs. Most treatments led to a significant reduction of metal(loid)s contents in biomass, mitigating contamination risks. The two different NPs had similar effects in many parameters, nH outperformed nZVI in terms of increased nutrients, C content, and enzymatic activities. On the basis of our results, combined biochar-NP amendments use, specially nH, emerges as a potential post-mining soil restoration strategy.
在这里，我们研究了不同的改良措施对降低砷（As）、铜（Cu）、硒（Se）和锌（Zn）相关风险以及改善矿山土壤生物地球化学功能的能力。为此，我们考察了纳米颗粒（NPs）和/或生物炭的效果，同时结合使用黑麦草（Lolium perenne L.）进行植物稳定化。在一个废弃的金属矿区周围采集了土壤样本。在含有不同组合的 NPs（零价铁（nZVI）或羟基磷灰石（nH））（0 和 2%）和生物炭（0、3 和 5%）的花盆中播种黑麦草种子。将植物种植 45 天后，评估植物产量和元素积累情况，同时还测定了土壤性质（土壤各部分的元素分布、肥力以及与微生物功能和养分循环相关的酶活性）。结果表明，与对照土壤和 NP 处理土壤相比，生物炭处理的土壤具有更高的 pH 值和更高的有机碳（C）含量，且含有更多的易分解 C、总氮和有效磷。NP-生物炭组合处理增加了可交换非酸性阳离子浓度，降低了可交换 Na%，提高了土壤肥力，降低了盐基度风险，增加了黑麦草生物量。添加生物炭增加了土壤酶活性，特别是脱氢酶和葡萄糖苷酶，而 NPs 的添加则促进了这一作用。大多数处理方法都导致生物量中金属（类）含量显著降低，降低了污染风险。两种不同的 NPs 在许多参数上具有相似的效果，nH 在增加养分、C 含量和酶活性方面优于 nZVI。根据我们的研究结果，联合使用生物炭-NP 改良剂，特别是 nH，可能是一种潜在的矿山土壤修复策略。
