Regionalização de vazões mínimas, médias e máximas na bacia hidrográfica do rio Itapicuru - BA

• Autor(a) principal: Albuquerque, Ytallo Rafaell Teixeira de
• Data de Publicação: 2019
• Tipo de documento: Dissertação
• Idioma: por
• Título da fonte: Repositório Institucional da UFS
• Texto Completo: https://ri.ufs.br/jspui/handle/riufs/14264
• topic: Recursos hídricos; Balanço hidrológico; Correntes fluviais; Bácias hidrográficas; Itapicuru, Rio, Bacia (BA); Multivariate analysis; Regression analysis; Granting; Cluster; Hierarchical; ENGENHARIAS::ENGENHARIA SANITARIA

The little fluviometric information related to the spatiotemporal inconsistency of available historical data has resulted in great restriction to represent the dynamics of water resources in hydrological studies, especially the flow rates. An alternative widely used in river basin surveys is the application of flow regionalization that determines their water availability through flow data. This technique allows the transfer of information between similar river basins, adjusted by grouping homogeneous regions, in order to calculate, in locations without data, the fluviometric variables of interest, thus forming regression models between flow, constituting as a fundamental piece for the planning and management of water resources, the electric and agricultural sectors and for the adoption of public policies. In this sense, the present work had as main objective to regionalize the maximum flow rates associated with 10-year return periods, long-term and minimum 7-day averages and 10-year return period in the Itapicuru River Basin, located at northeast of the State of Bahia, using, for that, hydrological, climatic and relief information. Using the hierarchical k-means hybrid clustering methodology, three homogeneous watershed regions were determined based on the explanatory variables: precipitation, evapotranspiration, precipitation-evapotranspiration ratio, area and normalized difference vegetation index - NDVI. Linear regression and correlation methods were used using the R software, which determined the mathematical models of flow regionalization, so that the results were obtained for the total watershed region and for the homogeneous region I, not proceeding to the results of the homogeneous regions II and III due to insufficient fluviometric data. The analysis of the obtained results considered the lowest Bayesian Information Criterion value, the smallest sum of the residual square and the best coefficient of determination for each adjusted model. All variables presented interaction in at least one adjusted model, with the exception of the NDVI explanatory variable, which was less expressive in the development of the proposed flow regionalization models, showing no relevant impact in relation to the performance of the other variables. In all regression analyzes, satisfactory results were observed, considering the statistical coefficients obtained, which indicate the significant relationship between the values of the explanatory variables performed with the aid of the applied model adjustment method, evidenced by the correlation coefficients equal or higher. at 0.85 or 85%, proving that remote sensing techniques associated with regression analysis yield good estimates. The product of this work is a useful tool in the execution of services such as the granting of the right to use water and it should be remembered that if there is a need to know the value of the flow in places where there are already fluviometric stations used in the determination. of homogeneous regions I, II and III, their values will be more accurate than the regional equation itself. Thus, one should choose, not for the calculation, but for its real value. Finally, the methods used were satisfactory and therefore applicable.