Forest restoration is a strategy to reverse forest loss and degradation. We overviewed deforestation in the period 1975–2018 in the Brazilian Amazon and the projects, techniques, and scientific publications conducted to recover forest in the area by 2019. We used GIS to assess forest loss and a systematic data collection gathered from 12 universities, five major environmental agencies, and an ad-hoc bibliographic survey that rendered information from 405 restoration projects and 152 published studies. The Brazilian Amazon has undergone an accelerated deforestation in the last 43 years, resulting in 20% (788,353 km²) of its territory deforested by 2018. Deforestation rate was 27,033 km² yr⁻¹ between 1975 and 1987 and 14,542 km² yr⁻¹ between 1988 and 2018 (1.97% yr⁻¹ of forest loss between 1975 and 2018). In 2018, 41 Amazonian municipalities were classified as priority areas for monitoring and control deforestation and 21 additional municipalities were deemed as areas with controlled deforestation. Our survey identified 405 projects of forest restoration in 191 municipalities between 1950 and 2017. The majority (229) of these projects used seedling planting as the main forest restoration technique. Forest restoration projects based upon agroforestry systems (144), assisted natural regeneration (27), and natural regeneration (5) were also identified. Despite a considerable number of projects and publications, the region still lacks scientific studies that reinforce the choice of best practices for forest restoration, and the information currently available is not enough to quantify what has already been recovered or the potential area to be restored.

Forest loss and degradation in the Brazilian Amazon due to mining activities has been intense for many years. To reverse this situation, a range of restoration programs for deforested and degraded areas have been created and implemented. The aim of this study was to analyze the tree composition, successional stage, dispersal and pollination syndromes, conservation status of tree species, and proximity to seed sources under different forest restoration techniques (seedling planting, natural regeneration, and assisted natural regeneration or nucleation) implemented in post-mining sites in the Paragominas municipality (Pará, Brazil). Sixty permanent plots with a restoration age of three years were selected for tree sampling. A total of 119 species, 83 genera and 27 botanical families were identified. Sites restored with different techniques significantly differed in tree composition. Seedling planting sites exhibited the highest abundance, species richness, and diversity values. These were dominated less by pioneer species when compared to the natural regeneration and nucleation sites. Entomophilic pollination and zoochory dispersal were highly represented in the three types of restored sites. Abundance and species richness were negatively correlated with distance from plots to seed sources, and they sharply declined in natural regeneration and nucleation plots at >250 m from seed sources. Four threatened species were identified in the restored sites. We conclude that a combination of different restoration strategies at three-year-old post-mining restoration sites in the Brazilian Amazon results in the recovery of considerable levels of local tree diversity.

The state of Pará ranks second in Brazilian mineral production, where bauxite accounts for 84% of total mineral extraction, with negative impacts on the environment as a result. The determination of objectives and targets using environmental indicators as a tool to evaluate forest restoration processes is essential in the recovery of these exploited areas. This study aimed at evaluating the efficiency of forest restoration techniques by means of 13 qualitative and quantitative indicators for monitoring post-bauxite mining operations. Permanent plots were implanted in revegetated areas with the use of two techniques: planting of seedlings and stewarding of natural regeneration. It is concluded that the techniques are efficient for the recovery of forested area. However, natural regeneration showed greater efficiency for restoration for Density, Erosion and Exotic Species indicators. Still, natural regeneration should not be the sole option in the processes of ecosystem restoration, since planting proved to be more efficient for some indicators.