ENVIRONMENTAL RISKS OF IRREGULAR OCCUPATIONS IN THE FLOOD PLAINS OF THE BACANGA WATER BASIN, SÃO LUÍS ISLAND, MARANHÃO

Abstract

The present study presents an analysis of the possible changes that occurred in the Bacanga River in the years 1960 and 2020. The initial base included a bibliographic survey regarding the environmental characteristics of the region, comprising the relief, geomorphology, pedology, hydrography, climate, vegetation and socioeconomic factors of the basin. Subsequently, the Qgis software was used to analyze the main environmental changes that occurred over the decades in the basin area. This information was related to the marginal areas of the basin that are lived by residents of the neighborhoods and that are subject to flooding. Based on the data obtained from the analysis of areas prone to flooding and the socioeconomic characteristics of the people who inhabit the region, management actions were proposed. The results obtained revealed a process of degradation of the lower stretch of the Bacanga River, following the construction of the dam, which led to the spatial settlement of the population. The reduction of approximately 35% of natural vegetation in the region demonstrates the level of anthropization that the basin continually suffers, in addition to processes of deterioration of the river channel, which was reduced by the silting process and alteration of water quality, once it passed by the damming process and limited its exchanges with the tide.