Santos Talita Raissa Silva, Santos Jessyca Adelle Silva, Pereira Eduardo Gusmão, Garcia Queila Souza
Departamento de Botânica, Instituto de Ciências Biológicas, Universidade Federal de Minas Gerais, Avenida Antônio Carlos, 6627, Pampulha, Belo Horizonte, Minas Gerais, 31270-901, Brazil.
Instituto de Ciências Biológicas e da Saúde, Universidade Federal de Viçosa, Rodovia LMG 818, km 06, Campus UFV-Florestal, Florestal, Minas Gerais, 35690-000, Brazil.
Environ Sci Pollut Res Int. 2023 Jan;30(2):3760-3773. doi: 10.1007/s11356-022-22376-3. Epub 2022 Aug 11.
The iron ore tailings released into the Rio Doce basin after the Fundão dam collapse (Brazil), suppressed a large extent of local vegetation. The use of native species and appropriate fertilization techniques, with less economic and environmental impact, must be considered in the process for the restoration of affected areas by the tailings. For this purpose, six native tree species, pioneer (Anadenanthera colubrina, Bixa orellana, and Peltophorum dubium) and secondary (Cedrela fissilis, Handroanthus impetiginosus, and Handroanthus serratifolius), were selected. We used different conditions of fertilization: (1) inorganic fertilization, (2) inoculation with arbuscular mycorrhizal fungi and plant growth-promoting rhizobacteria, (3) combined treatment (fertilizer + inoculum), to evaluate leaf nutrient concentrations, photosynthetic capacity [chlorophyll index, maximum quantum efficiency of photosystem II (Fv/Fm) and gas exchange variables], and oxidative metabolism (HO, MDA, and antioxidant enzymes). Inoculation resulted in higher concentrations of foliar nitrogen, especially in pioneer species. In all treatments, the secondary species exhibited iron values considered phytotoxic, but showed reduced photosynthetic capacity only when inoculated. The highest concentrations of MDA were observed in inoculated plants of both successional groups. The antioxidant system proved to be effective in preventing oxidative damage for most of the species. These results showed that the use of inoculum can be considered an ecological alternative to inorganic additives in the area affected by iron ore tailings. Despite presenting different photosynthetic and antioxidant strategies, the evaluated species demonstrated potential for use in tailings revegetation projects.
丰唐大坝坍塌（巴西）后，排入多西河盆地的铁矿石尾矿抑制了大片当地植被。在尾矿影响地区的恢复过程中，必须考虑使用对经济和环境影响较小的本地物种和适当施肥技术。为此，选择了六种本地树种，先锋树种（南美猴耳环、红木、盾柱木）和次生树种（裂叶香椿、锈毛番龙眼、锯齿番龙眼）。我们采用了不同的施肥条件：（1）无机施肥，（2）接种丛枝菌根真菌和促植物生长根际细菌，（3）联合处理（肥料+接种物），以评估叶片养分浓度、光合能力[叶绿素指数、光系统II最大量子效率（Fv/Fm）和气体交换变量]以及氧化代谢（过氧化氢、丙二醛和抗氧化酶）。接种导致叶片氮浓度更高，尤其是先锋树种。在所有处理中，次生树种的铁含量被认为具有植物毒性，但仅在接种时光合能力降低。在两个演替组的接种植物中均观察到最高浓度的丙二醛。抗氧化系统被证明对大多数物种有效防止氧化损伤。这些结果表明，在受铁矿石尾矿影响的地区，接种物的使用可被视为无机添加剂的一种生态替代方案。尽管表现出不同的光合和抗氧化策略，但所评估的物种在尾矿植被恢复项目中显示出应用潜力。
