SPATIAL DYNAMICS OF PERIODIC FLOODING OF THE CAUAMÉ RIVER IN THE URBAN EXPANSION AREA OF THE CITY OF BOA VISTA, RORAIMA

Abstract

Information on the spatial dynamics of the hydrological cycle in urban areas is essential for decision-making aimed at avoiding and/or mitigating environmental impacts. The study aimed to determine the impacts related to the dynamics of the hydrological cycle in the Urban Expansion Area-AEU of the city of Boa Vista, based on the great flood of 2011. 22.1 km² of riparian forests and 35.6 km² of Permanent Protection Areas-APP, were mapped on both banks of the Caumé river. The APPs overlap 8.5 km² (30.6%) of riparian forest areas. Estimated average values ​​indicate that a flood similar to the great flood of 2011 would inundate 24.6 km² of the Cauamé river basin, with 18.9 km² (76.0%) on the left bank and 6.0 km² (24.0%) on the right bank. The sum of the annual precipitation of the months of march, april and may explained 23.2% in the variation of the values ​​of the altimetric quotas and 49.2% in the variation of the values ​​of the flooded area in the period from 2000 to 2021. The results serve as a subsidy for policies and future works aimed at understanding the hydrological dynamics of the Cauamé river and its environmental impacts on the AEU of the city of Boa Vista, predicting its urban growth beyond the river channel.