Avaliação do potencial da restauração florestal na Amazônia Oriental: Estudos aplicados ao nordeste paraense.

Abstract

Brazil has a goal of restoring 350 million hectares by 2030, with methods and techniques that provide better ecosystem benefits coupled with the cost-efficiency process and, on the other hand, holds in its economy, activities that require the suppression of extensive areas, such as livestock, agriculture, and mining. Considering the impacts generated by suppression of vegetation and the search for efficient alternatives for the restoration of these environments, the present thesis aimed to evaluate the potential of forest restoration in the Brazilian Amazon, focusing on the northeast region of Pará, and to propose efficient restoration methods to post-mining reality. This Doctoral Thesis is divided into six chapters: (1) General Introduction, covering the main aspects present in the Thesis; (2), (3) and (4) Research Chapters, presented here in the form of scientific publications, sent to high impact international journals; (5) General Discussion, where we address the aspects of connection between the research chapters; and (6), Conclusions Chapter. In the first chapter, the evaluation of priority areas for restoration in the municipality of Paragominas was addressed, and the historical process of degradation in rural properties was evaluated and it was proposed to restore degraded Permanent Preservation Areas (PPA), as well as the possibility of implementing ecological corridors, and thus foster alternatives for the return of biodiversity. In this chapter, we identified 3,472.96 km2 of rural properties with degraded PPA’s that must be recovered. In the second chapter, the process of forest succession of an area mined by kaolin belonging to the company Imerys, in Ipixuna municipality, was studied, characterized by the great topographical disruption, in which it sought to evaluate the efficiency of a restoration method that is still not very widespread, of trenches, to evaluate the floristic composition of six forest species and litter stock after 18 months of implantation. The results demonstrated are promising, where the opening of trenches with the addition of organic fertilizer plus chemical fertilizer in the pits was positive in the development of the planted individuals, although there is a must to evaluate the cost-efficiency to demonstrate that the technique can be used extensive mining areas. In the third chapter, for the same area in succession process after kaolin mining, the objective was to evaluate the efficiency of the chemical attributes of minesoil, according to different fertilization techniques. The results showed that, despite the short time, the applied methodology favored the soil with good physical and chemical properties, rapid growth of planted individuals and a favorable environment for natural regeneration. In this way, the results obtained in these studies can be replicated to other municipalities to propose public policies in the search for the reduction of environmental degradation, as well as to propose viable alternatives for mining enterprises that require efficiently, to restore the mined environments.