Doctorado en Ciencias Biológicas y de la Salud, Universidad Autónoma Metropolitana, Mexico City, Mexico.
Instituto de Geología, Universidad Nacional Autónoma de México, Mexico City, Mexico; Laboratorio Nacional de Geoquímica y Mineralogía, Ciudad Universitaria, Mexico City, Mexico.
Sci Total Environ. 2022 Jan 1;802:149788. doi: 10.1016/j.scitotenv.2021.149788. Epub 2021 Aug 20.
In Mexico, millions of tons of mining wastes are deposited in the open pit. Their content in potentially toxic elements (PTE) represents an environmental risk. In the tailings, pioneer plant communities are established, associated with a determined diversity of fungi; plants, and fungi are fundamental in the natural rehabilitation of mining wastes. The objective was to evaluate the impact of the natural establishment of two plant species on the microbial activity, on the composition of the fungal community, and on the mitigation of the effect of PTE in a contaminated mine tailing. In a tailing, we selected three sites: one non-vegetated; one vegetated by Reseda luteola, and one vegetated by Asphodelus fistulosus. In the substrates, we conducted a physical and chemical characterization; we evaluated the enzymatic activity, the mineralization of the carbon, and the concentration of PTE. We also determined the fungal diversity in the substrates and in the interior of the roots, and estimated the accumulation of carbon, nitrogen, phosphorus and PTE in plant tissues. The tailings had a high percentage of sand; the non-vegetated site presented the highest electric conductivity, and the plant cover reduced the concentration of PTE in the substrates. Plants increased the carbon content in tailings. The enzymatic activities of β-glucosidase and dehydrogenase, and the mineralization of carbon were highest at the site vegetated with A. fistulosus. Both plant species accumulated PTE in their tissues and exhibited potential in the phytoremediation of lead (Pb), cadmium (Cd), and copper (Cu). Fungal diversity was more elevated at the vegetated sites than in the bare substrate. Ascomycota prevailed in the substrates; the substrates and the plants shared some fungal taxa, but other taxa were specific. The plant coverage and the rhizosphere promoted the natural attenuation and a rehabilitation of the extreme conditions of the mining wastes, modulated by the plant species.
在墨西哥，数百万吨的采矿废物被露天存放。这些废物中潜在的有毒元素（PTE）含量对环境构成了威胁。在尾矿中，先锋植物群落与特定多样性的真菌一起建立，植物和真菌在采矿废物的自然修复中起着至关重要的作用。本研究的目的是评估两种植物自然定植对微生物活性、真菌群落组成以及减轻受污染尾矿中 PTE 影响的影响。在尾矿中，我们选择了三个地点：一个无植被的地点；一个由 Reseda luteola 植被的地点；和一个由 Asphodelus fistulosus 植被的地点。在基质中，我们进行了物理化学特性分析；评估了酶活性、碳矿化和 PTE 浓度。我们还测定了基质和根系内部的真菌多样性，并估计了植物组织中碳、氮、磷和 PTE 的积累。尾矿的砂含量较高；无植被的地点电导率最高，而植物覆盖降低了基质中的 PTE 浓度。植物增加了尾矿中的碳含量。β-葡萄糖苷酶和脱氢酶的酶活性以及碳的矿化在 A. fistulosus 植被的地点最高。两种植物都在其组织中积累了 PTE，并表现出对铅（Pb）、镉（Cd）和铜（Cu）的植物修复潜力。有植被的地点的真菌多样性高于裸露基质。子囊菌在基质中占优势；基质和植物共享一些真菌类群，但也有其他特定的类群。植物覆盖和根际促进了自然衰减和采矿废物极端条件的恢复，这一过程受到植物物种的调节。
