Abstract
background: the recovery of areas impacted by mining activities is a major challenge and requires knowledge of how the biological and biochemical processes of the soil as well as the establishment of plant species are affected by mining residue. in this work, the influence of deposition of iron mining mud and tailings on soil biochemical attributes and the initial development of tree seedlings was studied in a simulated event in the greenhouse. pots (n = 27) with natural soil (2.0 kg) received deposition (280 ml) of iron mining mud or tailings and by three-month was cultivated with urochloa decumbens. at the end of this period, part of the pots was sampled and the soil biochemical activities were evaluated. then tree seedlings (schinus terebinthifolius and eremanthus incanus) were planted and cultivated for a year, when then shoot (sdw) and roots (rdw) dry weight were evaluated. results: deposition of iron mining mud and tailings did not affect microbial biomass carbon or basal soil respiration, however both conditions reduced (p < 0.05) β-glucosidase activities by up to 30%, and the easy extractable glomalin by about 19%. in addition, the mud deposition reduced (p < 0.05) the sdw and rdw of s. terebinthifolius by about 21% and 24%, respectively. nevertheless, uruchloa decumbens and eremanthus incanus had no variation in dry weight production between treatments, so they have good ability to grow settle in soil affected by mining residue. conclusion: this study shows that the sequential planting of u. decumbens and e. incanus can be an alternative for use in environments with deposition of iron mining tailings.
Highlights
The collapse of the Fundão dam in Mariana-Minas Gerais spilled 35-45 million m3 of iron mining residues over approximately 800 km in the Doce River Basin
Uruchloa decumbens and Eremanthus incanus had no variation in dry weight production between treatments, so they have good ability to grow settle in soil affected by mining residue
The Glomalin was affected (p < 0.05) by the deposition of mud and mining tailings, in both cases leading to a reduction of about 19% (p < 0.05) in its contents when compared to the non-impacted soil, after three months of cultivation of U. decumbens (Tab. 3)
Summary
The collapse of the Fundão dam in Mariana-Minas Gerais spilled 35-45 million m3 of iron mining residues over approximately 800 km in the Doce River Basin. The rehabilitation of extensive areas impacted by spills of tailings resulting from dam collapses, such as occurred at the Fundão dam (Mariana) and Córrego do Feijão (Brumadinho), in the State of Minas Gerais - Brazil, is a great challenge This process requires the recomposition of landscapes and the restoration of ecosystems at large scale levels. The use of native tree species capable of adapting to the new limiting soil conditions is essential, and some characteristics presented by tree species can be determinant for the success or failure of rehabilitation, such as: being resistant to pests and diseases, ease in acquiring propagules, adaptability, high growth rate, efficiency in absorption and use of nutrients, and tolerance to heavy metals (Accioly et al, 2000, Araújo et al, 2018) It has been reported the benefits of the associated soil microbiota with plants to achieve success in revegetation processes (Carneiro et al, 2008; Herzberger et al, 2014; Franchi et al, 2016; Santos et al, 2016; Rangel et al, 2017; Pedroso et al, 2018). Tree seedlings (Schinus terebinthifolius and Eremanthus incanus) were planted and cultivated for a year, when shoot (SDW) and roots (RDW) dry weight were evaluated
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Free) 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
