Abstract The physical and chemical properties of Technosol are crucial for forest restoration, as they can limit the development of pioneer vegetation in mined areas. In this study, we investigated how different restoration techniques affect the physical and chemical properties of the Technosol in two sites restored after kaolin mining in the eastern Amazon. Twenty months after planting seedlings, two distinct field experiments evaluated the efficiency of applying organic compounds (Topsoil - TS, Sawdust - SD, Cow manure - CM) in trenches and applying dolomitic limestone in pits of different sizes (Small pit - SP, Medium pit - MP, and Large pit - LP). The responses in the properties of the Technosol varied according to the management applied during the implementation of the restoration project. The techniques used to modify the physical and chemical properties in the study sites resulted in statistical differences between the kaolin mines in 21 of the 27 properties evaluated. The application of limestone reduced the toxicity of elements such as aluminum (Al), iron (Fe), and manganese (Mn) by more than 100% and increased the soil pH to over 5.5, while the incorporation of organic compounds restored organic matter (O.M), increased potassium (K), and contributed to moisture retention. We highlight the importance of proper management of the Technosol to mitigate the impacts of open-pit kaolin mining in the Amazon, as well as the need to implement more sustainable management policies and practices to ensure soil restoration after mining.
Oliveira et al. (Tue,) studied this question.