Monitoramento dos impactos ambientais causados pela extração de areia na região metropolitana de Manaus

Abstract

The population growth that occurred in Manaus, mainly from the 1960s with the creation of the Free Zone, culminated in the need to use aggregates for civil construction, mainly sand, which is one of the most widely used mineral substances in the world. The large amount of mining processes related to this substance, and the creation of the Manaus Metropolitan Region, creating different areas of mineral pressure, generate several environmental impacts.The research aims to analyze the environmental impacts arising from the activity of sand extraction in the Metropolitan Region of Manaus through the evaluation of the licensing processes and from a case study in the São Francisco branch north of Manaus, a zone of great pressure mineral. The research was based on a quantitative and qualitative approach through bibliographic, documentary, and case study technical procedures. Secondary data used referring to legislation and spatial data with the location of mining processes were acquired from the agencies responsible for licensing, municipal, state and federal. In the case study, the points visited in the field and the classification of satellite images from the last 11 years allowed the identification of environmental impacts related to sand extraction at the site. The licensing process has well-defined guidelines, but there are situations that should be better clarified, especially in decision-making, such as the lack of cooperation between agencies, the effects of simplified licensing and the lack of popular participation. The spatial distribution and analysis of mining processes show the importance of protected areas and managed in environmental control, and as a lack of management plans and zoning in these areas can be harmful, as well as identifying the main points of mining pressure and its associated impacts. In the study at São Francisco branch, the damages are related to the effects of the removal of vegetation, consequently the exposure of the soil, resulting in the loss of biodiversity, erosive processes and alteration of the hydrological dynamics, facts aggravated by the difficulty of recovering the area, by the abandonment of miners and the agencies that license and inspect. The application of environmental licensing proved not to be able to mitigate the negative impacts. Despite having a relevant importance in the quality of life of contemporary society, the extraction of this substance has caused several environmental damages. For being essential, solutions such as the improvement of environmental impact assessment tools, creation of management plans, economic and ecological zoning, and the integrated work of public agencies, are solutions that can improve the use of this substance and the maintenance of environmental quality a long term.