Journal of South American Earth Sciences xxx (xxxx) xxx Please cite this article as: Suzi Huf Theodoro, Journal of South American Earth Sciences, https://doi.org/10.1016/j.jsames.2020.103014 Available online 18 November 2020 0895-9811/© 2020 Elsevier Ltd. All rights reserved. Soil remineralization and recovery of degraded areas: An experience in the tropical region Suzi Huff Theodoro a, * , Fernanda de Paula Medeiros b , Marco Ianniruberto c , Tamiel Khan Baiocchi Jacobson a a Postgraduate Program of Environment and Rural Development (PPG-MADER), ´ Area Universit´ aria, 01, Vila Nossa Senhora de F´ atima – Campus UnB, Planaltina, DF, Brazil b Postgraduate Program in Soils and Plant Nutrition/University of Viçosa (UFV), Av. Peter Henry Rolfs, University Campus, MG, Brazil c Geosciences Institute – University of Brasília, Brazil – Campus Darcy Ribeiro, S/n, Brasilia, DF, Brazil A R T I C L E INFO Keywords: Degradation Recovery Remineralization Agroforestry Sediments Trˆ es maria reservoir Brazil ABSTRACT Many activities related to the expansion of food supply, energy and infrastructure result in great environmental impacts, whose most visible features are observed in the degradation of large areas. The present study demon- strates how the combined use of stonemeal technology and agroforestry systems can help to reverse such im- pacts, allying the recovery of degraded areas with agricultural and forest production. The study area is located in a hydroelectric reservoir affected by the siltation process and soil erosion in the hydrographic basin of the San Francisco River, Brazil. An Experimental Unit (EU) was set up in the Ecological Station of Pirapitinga (Trˆ es Marias reservoir). The design of the EU was based on a factorial design, with seven treatments applied on six native tree species, with three replications (21 blocks). The germination and establishment data of each species were considered in the different treatments. The oxides concentration and fertility level of sediments were analyzed for the determination of the sampling points in the reservoir. The experiment and evaluation were conducted over six years, and the sediments analysis presented high levels of the essential macronutrients K 2 O, MgO and TiO 2 , while CaO and Na 2 O levels were signifcantly low, due to their high solubility and mobility. The P 2 O 5 also showed equally low values. After two years, soil pH was balanced, especially in the blocks with mineral inputs. P, K, Ca and Mg concentrations were increased up to 5 times more than those of original soil of the EU, and the highest values were found in the remineralizer + sediment treatment. The use of geological material (e.g. mining waste) and organic compost was proved to be an adequate and sustainable technology to mitigate degradation processes. Besides, locally available sources of organic matter enhanced. 1. Introduction Throughout planet Earth’s evolution, the dynamics of the tectonic and weathering processes have stoned the ecosystems, providing the formation and diversifcation of the most varied features and environ- ments. More recently, the anthropic actions have interfered with the Planet’s superfcial dynamics, modifying the processes that occur in the pedosphere and biosphere, being soil erosion a direct consequence of the impact of changing land use that causes soil degradation and mobili- zation (e.g. Syvitski and Kettner, 2011). According to Lal et al. (1989), soil degradation can occur due to deforestation, inappropriate land use, high population density, urbanization, industrial activity and land tenure management which may cause alterations of soil’s physical, chemical and biological prop- erties and processes, such as: accelerated erosion, increasing wetness and poor drainage, laterization, salinization, nutrient imbalance, the decline in soil organic matter, and reduction in activity and species di- versity of soil fauna and fora. Such processes are especially intense in tropical developing countries, where a signifcant challenge is posed by the need to achieve food security while minimizing environmental impact (Scherr, 1999; Lal, 2001). Besides increased soil erosion, human action has also modifed sediment pathways and storage by damming rivers for the construction of water or hydroelectric reservoirs, which retain part of the sediment * Corresponding author. ´ Area Universit´ aria, 01, Vila Nossa Senhora de F´ atima – Campus UnB, Planaltina, 73345-010, Brasília, Distrito Federal, Brazil. E-mail addresses: suzitheodoro@unb.br (S.H. Theodoro), fernanda.medeiros@ufv.br (F. de Paula Medeiros), ianniruberto@unb.br (M. Ianniruberto), tamiel@unb. br (T.K. Baiocchi Jacobson). Contents lists available at ScienceDirect Journal of South American Earth Sciences journal homepage: www.elsevier.com/locate/jsames https://doi.org/10.1016/j.jsames.2020.103014 Received 15 July 2020; Received in revised form 3 November 2020; Accepted 4 November 2020