Estudo da evolução temporal dos bancos de areia no leito do Rio Choró, Ceará, Brasil.

Abstract

The activities of sand mining in the bed of the Rio Choró, they have been intensifying increasingly in recent years, in particular, in the stretch that passes through the municipality of Barreira, in the State of Ceará. This work had as objective to identify the evolution of the extension of sandbanks in the bed of the Choró River in the localities of Criancó and Cruz, in the years of 2013 and 2018 and to verify the environmental impacts resulting from the activities of sand extraction. Therefore, was used images of the Landsat-8 satellite allied to geoprocessing techniques and Geographic Information System. Done the process of classification of these images and verified its accuracy through the Kappa Index, was identified changes in the behavior of sandbanks. It was observed the increase, instability and spatial variability of the sands located in the fluvial channel in Criancó along with the absence of flow in some stretches of the river. In Cruz, the sandbanks presented a greater contribution. In five years, the environmental impacts were consolidated in the localities, resulting, mainly, in the intensification of sedimentation, erosion and deforestation phenomena on the margins, obstruction in the river and pollution of the water body.