Análise ambiental integrada da paisagem na bacia hidrográfica do rio Araguaia

Abstract

The Araguaia river basin – the field of study of this research – is located in an ecological transition area between the two largest biomes in Brazil, the Cerrado and the Amazon, attributing to it, in effect, a state of continuous pressure from agricultural expansion, since the last decades, in order to threaten the integrity of the remaining natural area and the connectivity between these biomes. The Araguaia River is one of the main river in the Brazilian territory, and represents the only major river system in Central and Southern Brazil that has not yet been dammed or affected by other direct human interventions in the channel. Furthermore, it is also characterized as one of the few large free-flowing rivers in South America. The basin also has the important remnants of natural Cerrado vegetation, with important areas for biodiversity conservation, in addition to presenting a complex flood plain, which corresponds to one of the largest and most diverse floodplains in the world (Planície do Bananal) and is characterized by being the most geodiverse in the Cerrado. The paths for the development of this research center on the integrated environmental analysis of the landscape in the Araguaia river basin. Faced with this need, the study of landscape dynamics and geoprocessing techniques through Principal Component Analysis (PCA) were used as theoretical foundations. The construction of this integrated environmental analysis of the landscape involved the acquisition and spatialization of the following environmental data (land use and coverage, pivots, deforestation, fires, conservation units, biodiversity, hydroelectric, caves, quilombola communities, indigenous lands and settlements), considered as essential data for the integrated analysis of the landscape in the Araguaia river basin. Therefore, the interaction between landscape elements, under the approach of geoprocessing and Principal Component Analysis (PCA), made it possible to carry out the main correlations from the Principal Components (CP's) in the Araguaia River watershed in 2019, showingeffective for the study area. The Analysis by Principal Components showed that there was about 72% of the total variability of the data; of these, the categories of caves, endangered and endemic species, fires, hydroelectric, deforestation and conservation units showed more correlations. It is also worth noting that the remaining Savanna Formation areas are a priority area for conservation, as they represent the natural vegetation that comprises a large part of indigenous territories and conservation units, as well as the highest occurrence of endemic species in the hydrographic basin. However, this region, for 2019, represented the area with the highest rate of deforestation and number of fires.