Mn concentration and mycorrhizal colonization in understory native species grown at areas of manganese mine tailings disposal

Abstract

Revegetation of areas with mine tailings should consider not only the best technique but also the choice of species adapted to this condition. This study aimed to analyze the occurrence of plant species, their Mn concentrations, and mycorrhizal colonization after implementation of two revegetation techniques (replacement of topsoil with natural seed bank and planting of seedlings) in an area of disposal of tailings from Mn processing compared to a native forest area as well as to a place that was not revegetated. Plant samples (at least three individuals/species) were collected from the understory at revegetated locations and forest. The established plant species and their Mn concentrations, mycorrhizal colonization, and forms of Mn in the soil were analyzed. The use of topsoil led to greater plant diversity. The high concentrations of Mn in the substrates did not affect the occurrence of vegetation in the understory and mycorrhizal colonization. The plant species established in the revegetated areas differed in relation to Mn concentration (471–27,842 mg kg−1 in leaves), Mn translocation factor (0.2–125.3) and mycorrhizal colonization rates (1–35%). Four potential Mn hyperaccumulators species were identified: Aparisthmium cordatum, Clidemia hirta, Socratea exorrhiza, and Vismia latifolia.